ETX-125EC USER FEEDBACK - SEPTEMBER 1999
This page is for user comments and information specific to the Meade ETX-125EC. Accessories and Feedback items appropriate to the original ETX model, ETX-90EC, and the ETX-125EC are posted on other pages as appropriate. If you have any comments, suggestions, questions or answers to questions posed here, e-mail them to me and I'll post them. Please use an appropriate Subject Line on your message. Thanks.
Please read an important announcement from Meade on the ETX-125EC.
Subject: ETX125 Back from Meade! Sent: Thursday, September 30, 1999 19:43:56 From: firstname.lastname@example.org (Bill Ramsey) I am glad to report that my ETX125 has been returned from Meade! For those of you who may have sent your unit back for repair, here is the good news: 1. The packaging has been changed to include more foam supporting the tube end and base when in the box. It also appears that foam has been added to reduce lateral shift. Foam blocks are located between the base and the bottom of the tube with cutouts for the mirror flip knobs and the focuser. 2. In general the scope feels "tighter". The focus knob feels firmer and the general "loose" feel the unit originally had is gone. 3. Collimation and image shift problems are gone. 4. RA and DEC circles were set properly. 5. The DEC motor has no apparent slop in the gearing. RA still has a slight delay, but better than before. While I have not had time for a "complete" performance review, my initial experience is good. The scope was mounted on a JMI Megapod ( I will try and send some pictures and a review of this tripod later) and carried out to the front porch for a quick look at Jupiter. Light pollution at this location is very bad and some nights you have trouble finding some constellations. Tonight is almost that bad. However, even with Jupiter low on the horizon, the view was great. Banding clearly visible with 4 moons is a pretty sight. Focusing is no longer the delicate task it was before. Moving from the 26mm eyepiece to 18mm and then to 9mm is easy when the image is not shifting around! This weekend I hope to get away from the city lights to the local Boy Scout camp for an Eagle presentation. If the weather is good, another report will follow. Now I can play with that Autostar! Bill
Subject: Comparison Sent: Thursday, September 30, 1999 19:32:44 From: email@example.com I?ve been a reader for several months and would like to share some thoughts on the ETX and Nexstar since I think I?m in a pretty unique position of having bought and tested both . My story is pretty simple, I bought an ETX-125 on July 19 after two months on the waiting list. The telescope looked great out of the box and was put to use over a couple of nights of average-good seeing. After performing the drive training we took the scope out for a test drive. Like many ETX-125, the collimation was off significantly. I returned it to Meade and because of the delays in returning the unit (seven weeks and counting), I was given the option by the retailer of returning it (when it was sent back by Meade) and accepting a Nexstar instead, which I did. I?ve had the Nexstar out for five nights in average-good seeing and both scopes were given a very similar test. Given the collimation problem, it would not be fair to compare optical quality of the ETX to the Nexstar but I can comment on a great many other things. Note: On the second night of ETX-125 observing a friend brought over a ETX-90/EC so I was able to do a side-by-side comparison between the two Meade models. Optical Performance Both the ETX-90/EC and the Nexstar produced sharp, contrasty, images with stars showing clear diffraction rings at high magnification. Although I feel the Nexstar produced better images (particularly in brightness), the ETX-90/EC clearly performed impressively. Since, I?ve had significantly more time with Nexstar, I can make a few additional comments on its performance. Nexstar easily split epsilon Lyrae and maintained the separation while tracking. 61 Cygni and Albireo were breathtaking. Even from my hideously light polluted city location I was able to see the dim center of the ring nebula. I was able to watch mountain tops on the moon as they passed the terminator. There was also significant image shift on focusing with the ETX but none with Nexstar. The focusing on the 125 was much improved over the 90 but not up to the Nexstar?s smooth movement. I am looking forward to S&T?s review of both scopes to settle the optical issue once and for all. Rating: FOCUSING SMOOTHNESS AND LACK OF IMAGE SHIFT ARE WINS FOR NEXSTAR. NO OTHER OPTICAL DETERMINATION CAN BE MADE AT THIS TIME. Stability A clear win for Nexstar, even with only one fork. The ETX shook significantly and took several seconds to calm down after being bumped (ETX was bolted down to a converted old heavy duty SCT tripod and was securely attached). The tube exhibited looseness in the mounting which caused the it to drop significantly when heavier eyepieces (i.e. Televue Radian) were changed. Nexstar has not demonstrated this. Nexstar took approximately a second to damp down after being bumped (it was mounted on a Megapod) and would have been sufficiently stable for a camera mounting. Rating: NEXSTAR Go To Accuracy Both scopes GoTo performance was excellence. The ETX-125 put alignment stars in the 26mm field 4 out of 5 attempts and was 4 for 4 on the double stars I looked at. It put 3 out of 4 deep space objects (M31, M39, and the Ring Nebula in Lyra were in but it just missed on another). Much later in the evening it put Jupiter dead center. Nexstar was 4 ?4 on alignment stars in the 25 mm field and a surprising 8 of 9 on double stars just missing 61 Cygni (a change to my new 40mm eyepiece reveled its position). Nexstar was also perfect with the four deep space objects I looked at (M31, M39, the Pleiades and the ring nebula ). I also put Jupiter and Saturn on the edge of the outer field as well. It has no coordinates for the moon so no attempt was made. Since it has no finder scope or analog setting circles, the pointing accuracy is pretty much essential for Nexstar. Both scopes pointing capabilities are bargains. Rating: SLIGHT EDGE TO NEXSTAR Tracking Both scopes performed well with tracking. Nexstar actually kept 61 Cygni in the field for over 30 minutes while I took a phone call. I have been clearly impressed with both scopes capabilities here. Rating: SLIGHT EDGE TO NEXSTAR Ergonomics I liked the fact that the power source and computer control were in the base of the ETX. The position of the controller in the arm of Nexstar (and the short cord) makes it inconvenient to put the controller down without putting it away. I actually found myself just letting it hang down which I?m sure can?t be good for the wiring connections. Although I didn?t experience any cord-wrap problems the possibility exists for it with the Nexstar power cord. The battery compartment on Nexstar is much easier to get into than the ETX. Rating: SLIGHT EDGE TO ETX-125/EC Database I was pleased with both databases. The lack of upgradeability on Nexstar didn?t concern me since it?s database has all the objects I?m really interested in. In fact, I don?t really see much difference between the 14,000 entry ETX database vs. the 18,0000 for Nexstar. For people looking to add earth-orbiting objects or other targets of opportunity to the database, the ETX would present a good choice. The Nexstar can be targeted using the RA & Dec coordinates in the hand controller (kind of like digital setting circles) but the lack of a finder would force me to use my 40mm eyepiece as a ?finder? for faint objects. Rating: EVEN Accessories Both are similarly configured. I liked the 26 mm Plossl eyepiece that came with Meade (I?ve since purchased the 6.4 SP and the 13.8 SWA from Meade). The 25 mm Celestron matched the sharpness of the Meade but didn?t have as much field. The right-angle finder scope on the ETX is quite convenient, even with the ?cross-bars?. Although the StarPointer with the Nexstar is easy to use, I?m still toying with putting either a 6X30 or a used 8X50 on the Nexstar for the previously mentioned reasons. The Nexstar Instruction manual is superior to the Meade both in terms of quantity of information but also ease of use. Nexstar came with an AC cube which is a nice touch. Rating: EVEN Summary The scope that really impressed me it?s Bang-for-the-buck was the ETX-90/EC. Although Nexstar was optically superior (probably the result of aperture size) it more than held it?s own. It?s definitely more portable than the two 5 inch models. I will admit that I was disappointed with the ETX-125. It seemed to present me with no real advantage relative to the ETX-90 except for aperture, and the optical quality was impossible to judge because of the collimation troubles. The elected to keep the Nexstar (in spite of the $140 price difference) and continue with the return of the ETX for several reasons: 1. Nexstar is optically an excellent scope. 2. Pointing accuracy is excellent and I thought it was slightly better than ETX-125 3. Stability of Nexstar over ETX. It is just a more solid scope. 4. Vendor Issues: My experience with Meade has demonstrated possible trouble spots that are generally indicative of operations problems. These included: Lack of quality controls: I was told on two occasions by Meade reps that the secondary baffle needed to be redesigned and that was why there was a delay in getting the ETX back from service. Meade continues to claim there is no problem. Honesty is sometimes the best policy, especially when your customers realize that you?re not being honest. I returned my scope on August 5 with arrival at Meade on August 12 (confirmed by UPS). When I called on August 18, no one knew where it was. I was later informed that it had not been received until August 18 ?according to the computer?. It?s quite evident that something happened to the scope between the time it was received on 8/12 and it?s magical reappearance on 8/18. My point is: when basic processes (Receiving) start to go bad, it could be a sign of larger problems. Disinterested customer service: Anyone who has dealt with Amy at Meade customer service knows what I?m talking about here. Even the retailer I bought the scope from said ?you must have been talking to Amy? when I mentioned the fact that I would call and be told that there was no way that she could find out anything about my scope and that she couldn?t help me. Delays in updating their web-site: This is like sending out-of-date and inaccurate literature to customers. Web sites are your front-door to the eCommerce world. Unfortunately, it is ?frills? like this that get cut when companies start to feel the fiscal pinch. Meade has introduced a lot of new products this year and it would stress any company but especially one the size of Meade. A now for some kudos (I don?t work for these people or sell telescopes but I really appreciated their professionalism) Retailers: Astronomics and Shutan Camera were phenomenal in the customer service they provide. Accessories: Megapod is solid as rock (but it is a little more heavy than I would have liked). Great for both ETX and Nexstar. Highly recommended ! I also strongly recommend getting a portable power supply (about $60). It seems that you pay for it after about the third week of using it. Meade and Scopetronix eyepieces have been a pleasant surprise as well. Steve (SNAGEL212@yahoo.com)
Subject: ETX-125 has returned from Meade in just 2 weeks!!! Sent: Tuesday, September 28, 1999 09:57:05 From: firstname.lastname@example.org (Robert Lonn) My ETX-125 has returned from MEADE after only 2 weeks. Living in San Diego keeps UPS travel time down to one day. Clouds rolled into San Diego early last night so I only tested it inside my house, looking outside a window. Image shift is near zero, collimation is right on. This is not my original unit I sent in. AZ lock down seems very tight, and rotation on the base unit seems tight as well, not LOOSE as was my other unit. Drive motors seem noisy compared to my other unit, but MEADE may have changed them in this upgrade to deal with drive problems. They tell me the more precise you want it to track, the louder the motors get that can accomadate this??? I will be away on business for a few days but wanted to get this information off to everyone. Weather permitting, I can do a better evaluation with Stars this weekend. With mine returning in only 2 weeks, my guess is many others may be on the way back as well. Meade told me it was not going to return before October 6th, they may be working overtime and weekends to get these upgraded. Call Meade to see what the status is with your unit. Lets use this forum to compare scopes and see what the new improved ETX-125 are like! Robert Lonn San Diego
Subject: ETX 125 experience. Sent: Monday, September 27, 1999 12:41:17 From: email@example.com (MARK A MARTELLO) I visited several stores selling the ETX-125EC. In every instance I observed that the secondary baffle had come loose and was laying in the telescopes tube. In some cases the primary mirror had been scrached by the baffle, possibly rolling around during shipping. Can anyone comment on this?
Subject: etx 125 experience. Sent: Friday, September 24, 1999 17:57:27 From: Appleden@webtv.net (Dennis A Traverso) I just found your web site. I Wish I had known about it a lot sooner. I own a 90 mm. etx and also the new etx 125. My 125 is now on it"s way back to Meade for the update. I just want you to know that your web site and all it"s contributors have been like a light at the end of a very dark tunnel for me. I will not give up on Meade yet. If all the flaws can be worked out of the 125, it is exactly the telescope that I have always wanted. There is nothing like it on the market today. I enjoy viewing the moon and planets on clear nights and I also like to take my scope to the shore and view ships at sea, wild life etc. in daylight. You know what would have been nice? If Mead had come forward and notified all of us etx 125 purchasers that there was a problem and recalled the units. That would have eliminated all of the confusion, speculation, gossip and hard feelings. Come on Meade, you are supposed to be the best, show us why! Mike, your web site is very important to all of us etx owners and I thank you for it. I will be watching, and contributing what I can. Sincerely...Dennis.
Subject: More NexStar vs. 125 info Sent: Friday, September 24, 1999 08:34:34 From: firstname.lastname@example.org (Gary) Well, I haven't griped about my 125 still being backordered from natural wonders (I was promised one about 3 weeks ago) and still don't know if my 90 will finally track with 1.3b finally installed, so I've been thinking about jumping ship (like a rat) - i've checked out a couple of NexStar pages, and generally the reviews have been favorable. One review mentioned the object was outside of the eyepiece by a consistent amount - he mentioned he trained on a star by the horizon, and another near the zenith - both no-no's per meade - the horizon has distortion, and the zenith can have a wide margin of error - a few people mentioned that their NexStar does not give a below the horizon error, so for those objects it will slew and point at their feet! although not claimed to be harmful, this is obviously a case where a software upgrade would allow the scope to warn the user about a below the horizon error - i don't know if an upgrade would require the user to open their scope and replace eproms (seems silly compared to the autostar's ability to download). In all, it seems the NexStar may execute somewhat better than the 125, but i still think it was poorly designed in its inability to upgrade. Also, now that comet lee is somewhere around, i like the fact that i COULD have the scope potentially slew to it, or the space station, mir, etc. - the fact that the scope can't find the moon is another story... Happy seeing, Gary
Subject: ETX-125 repair update Sent: Thursday, September 23, 1999 10:08:59 From: Robert.Lonn@cox.com (Lonn, Robert (CCI-San Diego)) I was also told by Meade that my scope was awaiting a new part for the collimation issue. When I asked if this would allow fine tuning of the focal lens system, he did not know for sure. Apparently the scopes are all undergoing all the upgrades now, and when the new part comes in will be a fast install process and alignment to solve this last issue. One other bit of news. It appears that these reworks are adding about $100.00 to the cost of our scopes!! This may and will lead to a price increase in the future for sure. So all of us will get a better and even more expensive scope when they finally come back. Being in the San Diego area and only down the road from MEADE in Irvine, mine will take just a day to get to me. Weather permitting, I hope to test it ASAP and post my findings here. I also talked to Thomas Bisque about his "THE SKY" software and the ETX125- Autostar issue. They are working on a patch, but still feel that MEADE can make one simple change in the Autostar to resolve the issue. Since they have received numerous calls about this they are working on a patch. Robert Lonn WA6PHN
Subject: 125ETX-EC review in S&T Sent: Wednesday, September 22, 1999 19:16:51 From: email@example.com (Lynn Snyder) An excellent 125ETX-EC review in S&T. Some items from the S&T article that may not be addressed by the Meade service announcement are outlined below: 1. Off-axis Coma was present in the unit tested in S&T. S&T then questions if the optical recipe of 125 may be different from the 90, leading to this condition. 2. Large central obstruction (40%) will lead to reduced optical contrast. Is this the case with the 90, or is the percent obstruction less? If the percentage is the same in the 90, then it should not be a concern in the 125. The same standard should be applied in case of the 125 as the 90. 3. 8x25 finder displayed slightly off axis stars as "astigmatic streaks". 4. Altitude induced motor vibrations rendered star images "bloated up", leading to resolution problems. 5. Image shift of 2 arc minutes in 1 test unit, and a "dead spot" in a second test unit observed when focussing. 6. 87% Autostar success rate in placing the object within the 26 mm eyepiece FOV. 7. Tripod vibration problems and tripod imbalance problems with 125 in polar orientation. I believe more dialog and detail is needed to understand exactly how Meade is correcting the the problems identified in their service announcement, as well as how they will address the additional problems discovered in the S&T review. Normally Meade has been quite forthcomming with this kind of information, and I would anticipate the same professional response to the issues raised here. The user community is generally quite interested in this kind of forthrightness, and would appreciate Meade putting the issues to bed, and setting the record straight. Lynn Snyder
Subject: Fw: Meade's ETX-125EC Test Report In error as to Central Obstruction Sent: Wednesday, September 22, 1999 17:02:44 From: firstname.lastname@example.org (Wayne Gatschet) More from Sky & Telescope ---------- > From: Dennis di Cicco > Subject: Re: Meade's ETX-125EC Test Report In error as to Central Obstruction > Date: Wednesday, September 22, 1999 5:47 AM > > Wayne, > > >From the e-mail that we've received so far, it appears that you are > right about the confusion, though I'm quick to point out that the 40% by > *diameter* was clearly stated in the text. It was the caption that > appears to have caused the confusion. > > As noted in that article, the NexStar 5 (Celestron's 5" SCT) was > introduced just as we were writing the ETX review. We now have a revised > ETX-125EC (excellent collimation, no focus shift, and smoother drive) as > well as a NexStar in our hands for testing. We are checking out both > scopes and will have a report early next year. The December issue is > about to go to the printer and we are wrapping up the editorial copy for > the January issue now. The report will likely appear in the February > issue if all goes according to plan. > > Regards, > D
Subject: Where is my ETX-125?????? Sent: Tuesday, September 21, 1999 18:23:54 From: email@example.com (Anthony Pisano) I originally sent in my ETX-90 to Shutan Camera and Video in Chicago for a trade up to the ETX-90EC. The day before they were to send the 90EC they called to inform me that a 125EC was going to be available in 8 to 12 weeks. Well, I'm still waiting. I was suppose to receive the 125EC in early July 99. I spoke to Mr. Shutan and he said the I was the third on the list when the next batch comes in. He also said that Meade had stop all shipments of the ETX-125 until the problems with the scope are resolved. I'm tired of waiting for this scope. Can anyone give me an idea of what to do????? Best, Anthony J. Pisano firstname.lastname@example.orgMike here: If you haven't already read it, see the Meade announcement noted at the top of page. Deliveries of repaired and new units are resuming so stay in touch with Shutan. Or you can call Shutan and cancel. Your choice.
Subject: Fw: Meade's ETX-125EC Test Report In error as to Central Obstruction Sent: Tuesday, September 21, 1999 17:37:50 From: email@example.com (Wayne Gatschet) I sent an e-mail to Sky & Telescope complaining about their article on the 125 got two responses as follows. Thought I'd pass it on. ************** e-mail one *********** ---------- > From: Dennis di Cicco > Subject: Re: Meade's ETX-125EC Test Report In error as to Central Obstruction > Date: Tuesday, September 21, 1999 1:22 PM > > Wayne, > > The obstruction is indeed 40% by diameter and we say as much in the > review. While the area is smaller (percentage-wise), it is the central > obstruction's diameter that degrades the image quality, and I quote from > the text on page 63: > > "... the 125EC's large central obstruction -- nearly 40 percent the > diameter of the aperture. An obstruction this size has the effect of > reducing the 5-inch scope's contrast to that of an optically excellent > unobstructed 3-inch instrument (see "Rules of Thumb for Planetary Scopes > -- I," Sky & Telescope, July 1993, page 91)." > > Check out that 1993 article for the details. > > Regards, > Dennis ************ e-mail two *********** Wayne, Here's a good Web site regarding the issue of obstruction size: perso.club-internet.fr/legault/obstruction.html --D
Subject: ETX-125 Sent: Tuesday, September 21, 1999 16:48:50 From: Dean@cwdi.com (Dean) I spoke with Meade this afternoon about when our 'remanufactured' 125's will be ready. The tech told me that they have redesigned a part and now are waiting for it to be made and shipped to them. He said it should be about 2 weeks until they are ready to ship and that the 'new' scopes will be outstanding and trouble free. I do hope he is right. It would be interesting to hear what other people are being told. As for the S&T report, he said that they WILL do a new review shortly after the scope is reworked.
Subject: ETX125 Sent: Tuesday, September 21, 1999 11:50:13 From: RSDKIRK2@aol.com Greetings and salutations; I am writing to put some of my input in about the 125ec. I am relatively new to astronomy, and this is my first real telescope. After doing considerable homework I decided that my first scope would be the 125. However, when I received my scope from the first Meade shipment I experienced some of the focus shift problems that other people have had problems with. So I took my scope back to Natural wonders and nearly considered waiting for a Nexstar 5. But, I decided to give the 125 one more chance. So when the second shipment came in I got a replacement scope. And, boy am I glad that I did. My first night out I turned the scope on Jupiter, and what a spectacular view it was. I could see four bands and four moons. I couldn't see the red spot but I don't know if it was around at that time. But the real breathtaking image was when I turned my scope on Saturn. The image was so surreal that it was almost a religious experience. The image was crystal clear and floating in the blackness of space that it didn't seam possible for this to be real. And this was just the 26 mm eyepiece that was provided. The next day I ran out and got two more eyepieces. I was out again that night. This time I used my autostar. The setup was easy. The first thing that I looked at was the Pleides. The autostar took me right there. Then I turned to M31 and again the auto star took me right there. After that I looked at a couple of globular clustars.I saw more in one night with the autostar than I could possibly have dreamed. And, I am learning the night sky at a faster pace. My point is: I see a lot of Meade bashing out there but, I think that even though Meade "goofed" they were quick to fix the problem and that the 125 was well worth the wait, and if I had it all to do over again I would. May the Force be with you:) Scott Davis Newbie Richmond Indiana
Subject: ETX-125 secondary blockage Sent: Monday, September 20, 1999 09:47:48 From: JDeriso@Alphaind.com (Deriso, John) There's been a lot said debating the 40% blockage reported by S&T. I suggest folks take a look at the photo on Al Nagler's page www.rahul.net/amall2/tvo/pg5.htm and get an idea to actually measure the blockage.
Subject: Aperture, ad-speak and misplaced faith. Sent: Monday, September 20, 1999 08:38:40 From: firstname.lastname@example.org.McMaster.CA (Clive Gibbons) WRT the "clear aperture" of ETX telescopes, please be aware that this value is given for the aperture at the corrector lens. The primary mirror sizes of the ETX scopes are larger than their clear apertures, to reduce the effects of off-axis vignetting (light loss). One should not think that the "aperture" of a Mak-Cassegrain is equal to it's primary mirror size. If you buy an ETX-90, you get 90mm of aperture and if you buy an ETX-125, you get 125mm... no more. Also, before anyone starts quoting Meade literature and/or asking for a retraction or apology from S&T, consider the following; Meade lists "secondary *mirror* obstruction" in their advertising material. The figures they give relate to the sizes of the spot secondary mirrors in their Maks. They coyly ignore the additional obstruction contributed by the secondary baffle cones in these scopes. So, what they print is *technically* true but apparently misleading to more than a few ETX users. I think this shows that one should read any manufacturer's promotional literature very carefully, before deciding who's right or wrong. Sincerely, Clive Gibbons Technician, McMaster University, School of Geography and Geology.
Subject: Kevin's quest for a reference Sent: Monday, September 20, 1999 06:55:01 From: GallJJ@cdm.com (Gall, John) A good reference is Telescope Optics by Rutten and Van rooij. See http://www.amazon.com/exec/obidos/ASIN/0943396182/qid=937835193/sr=1-11/002-7460508-7026453 Or, Clark's Visual Astronomy of the Deep Sky. BTW, this same reference suggests that the baffling on a mak-cass is intended primarily for improving daytime use. Presumably because oblique light rays are far more common in the day, than at night. Of course for bright, extended objects like the moon, this may also have some impact. I'm a neophyte here - can anyone comment on this topic ? john
Subject: Re: ETX-125 vs ETX 90 Sent: Friday, September 17, 1999 12:11:05 From: email@example.com (Kevin P. Kretsch) With regard to my previous comments on the central obstruction of the ETX-125 and the S&T review... The review is now on the S&T webpages, and looking at the photographs there is very clearly a large central obstruction! Measuring the secondary baffle at the flared end IS the correct thing to do, as the rays passing through the centre of the Matsukov corrector are practically undeviated and will be obstructed by almost the full diameter of the baffle. However, this is a 40% obstruction by diameter, about 16% by area. While bigger than I would like to see, particularly considering the size of the secondary mirror, the equivalent available area is the same as a 4.5" scope, and the S&T comparison to an unobstructed 3" scope seems overly harsh, though it does ONLY refer to contrast. Contrast seems to me to be an elusive thing to talk about. I have yet to hear of a good physical explanation of this. If anyone can direct me to a good optics text here I'd really appreciate it! Incidentally, this an identical size central obstruction to that on the Nexstar 5, so at the same magnification the two telescopes can be expected to have identical images (all else being equal). Have a good weekend, Kev. --- Kevin P. Kretsch B.A.(Mod.)Phys e-mail: firstname.lastname@example.org Photonic Materials Group, Tel: +353 1 608 1324 Department of Physics, Fax: +353 1 671 1759 Trinity College, Dublin 2, IRELAND.
Subject: 40% obstruction by diameter (not area) in ETX-125 Sent: Friday, September 17, 1999 09:16:36 From: email@example.com.McMaster.CA (Clive Gibbons) There seems to be some confusion, misinformation, etc., arising from S&T's review of the ETX-125. Specifically, some people are disputing the author's claim that the ETX-125 has an approx. 40% obstruction by diameter (n.b., this figure is a percentage of the scope's clear aperture, which corresponds to a blockage of 16% by area). Just to set things straight, I think it's worth noting that the review's author (Gary Seronik) is a very experienced and knowledgable amateur astronomer, who is aware of the properties of different optical designs. In light of this and the findings from other reputable sources, I submit the following to anyone who might be interested... ************************************************************************ WRT the discussion of ETX-125 obstruction size, there's a few points worth considering: 1) The corrector plate of a Schmidt telescope *is* optically active. It is not just a "plain flat glass plate". It has a complex, 4th order aspheric curve which weakly diverges light towards the edge of the plate and weakly converges light closer to the centre of the plate. 2) The corrector of a Maksutov is a *very* weak negative meniscus lens. It diverges light a bit more than the SCT corrector, but not by much. It's weak correction is least apparent towards the centre of the corrector lens (just where the secondary baffle sits), so the very, very slight divergence present in that zone has precious little effect on minimizing the blockage caused by a truncated-cone shaped secondary baffle. The divergence caused by a Mak corrector lens *in no way* approximates the angle of the secondary baffle cone. Therefore, a direct measurement of the "big end" of the secondary baffle will result in a realistic value for the actual secondary obstruction size. ************************************************************************* I hope this remedies some of the speculation that's been recently generated about the obstruction size of the ETX-125. Clive Gibbons, Technician, McMaster University, Hamilton, Ontario, Canada.
Subject: ETX 125 Sent: Friday, September 17, 1999 05:56:27 From: firstname.lastname@example.org (Gary) JK Saggese posted some mathematical concerns about the clear apeture of the 125 vs. 90 - per Anacortes Telescope, the apetures of the 90 and 125 are LARGER than one might think - the 90 is actually 96mm, with an unobstructed apeture of 90, while the 125 is actually 138 mm, with an unobtstructed apeture of 127 - i recommend he plugs in those new numbers. A few years ago there was a class action lawsuit against computer monitor manufacturers, because a 14 inch monitor might have an outside case measuring 14", but a "Viewable Image Size" of 12.1 or so - I suspect Meade learned from the monitor's mistakes!
Subject: Central obstruction Sent: Thursday, September 16, 1999 12:35:47 From: RLambert@ene.com (Lambert, Ralph) In response to the person writing about the central obstruction of the ETX, 9.8% for the 90mm and ~40% for the 125mm. The 9.8% is of the total surface area, but the 40% is of the diameter, ie it would have a diameter of about 50mm. 5"sq - 2"sq = 21 square inches open, or a central obstruction of 16% of the area. Ralph
Subject: Re: ETX-125 vs ETX 90 Sent: Thursday, September 16, 1999 07:46:53 From: email@example.com (Kevin P. Kretsch) Re: JK Saggese's message on the 125 pages. I would amazed if Meade produced a telescope like the ETX-125 only to have one of the baffles reduce the amount of light. This would quite simply be a waste of glass, mirror, light, and money! I doubt a company with the reputation and quality of Meade would not make such a gross error. I would not normally ask S&T to recheck data used in their reviews, but until they do, I'll take a large pinch of salt. John Zito (125 feedback, same date) has also suggested that S&T are in error here. As regards the secondary obstruction, the difference is resolving power is not something to worry about for most telescopes. The Dawes limit (usual number referring to resolution) is a good but approximate number. As far as I remember Dawes came up with his number 'in the field' while observing double stars. It will apply equally well to most telescopes, but ultimately is only as good as his eyes (which to be fair were pretty good!). Clear skies all, Kev. --- Kevin P. Kretsch B.A.(Mod.)Phys e-mail: firstname.lastname@example.org Photonic Materials Group, Tel: +353 1 608 1324 Department of Physics, Fax: +353 1 671 1759 Trinity College, Dublin 2, IRELAND.
Subject: The 40% obstruction of the ETX 125 amounts to 16% obstruction. Sent: Thursday, September 16, 1999 06:32:14 From: email@example.com (Eric Sinn) Even if you accept the S&T figure of 40%, that is still just 40% of the diameter. Total area obstructed is the square of the diameter. Thus, scope diameter is 125 mm. 40% is a 50 mm circle. area of a 50 mm circle is 19 square cm. Area of a 125 mm circle is 122 square cm. So even if the central obstruction is 40% of diameter, actual obstruction is only 16%. I have a question. I am thinking of getting either an ETX125 or an 8 inch SC scope. The price is about the same. I've never used a telescope before. Can someone who have experience with a German equatorial mount and an ETX please tell me. How long does it take to set up an 8 inch sc scope and align it? How long does it take to set up the ETX (3 or 5 inch) and align it? Are the stars and celestrial objects hard to find manually? How much training is necessary to learn to find things manually?Mike here: The larger the scope the more difficult to move it will be. But once you have the scope moved, alignment is usually just a matter of tweaking the position. Aligning a computer like the Autostar to alignment stars will only take a couple of minutes (normally). Then you are ready to go. Learning the sky is not difficult; people have been doing it for centuries. Using a computer-driven telescope will make finding objects easier but not always perfectly easy.
Subject: ETX-125EC vs Nexstar, and stuff Sent: Thursday, September 16, 1999 01:35:47 From: firstname.lastname@example.org (Wayne Gatschet) Hi Mike, glad your back! Several things, first my local dealer told me that if you order a 125 today, to expect delivery sometime around June of 2000. Talked to OPT about my order and when they expect shippments from Meade to resume, and was told "Any day now, but I can't tell you in which month" #$%@! The Sky & Telescope review bothered me. Read on ETX discussion group that the 125 had 40% obstruction and the Nextstar 16%. Did the math based on that and came out with the 125 being equivalant to a 3" unobstructed scope, and the Nextstar equivalant to a 4.2" unobstructed scope. That would make the Nexstar with 98% more light colecting ability, twice that of the 125. Something is very wrong here! Sounds to me like either S&T made a mistake and Meade needs to have a little talk with them, or Meade needs to do major redesign of the 125. To confuse matters even more Meade's Catalog (which I have) lists the central obstruction of the 90EC as a percentage of diameter as " 1.1" (27.9mm);9.6% " and the 125EC as 1.55" (39.4mm);9.6%. Now I did the math, and you have to remember you are dealing with circles inside of circles so you must apply the geometry of circles in any calculations. I assumed the 1.1" & 1.55" listed in the catalog are the diameters of the obstruction. By my poor calcs, the 90 has a 9.9% central obstruction and the 125 has a 9.6% obstruction. This would make the 125 a stellar scope compared to the 16% obstruction of the Nextstar (assuming the Nextstar is 16%). Just looking at photos of the two scopes it looks to me like the Nextstar has a larger obstruction. So at 9.6% that would make the 125 equivalant to a 4.5" unobstructed scope, and at 16% the Nextstar as a 4.2 unobstructed scope. WOW! Well this has left me TOTAL confused and don't know who or what to believe. Easy solution though, all you need to do is measure the diameter of the central obstruction on the Nextstar, 90 & 125 and do the math. I don't have access to either so its up to all of you who do. Here's a math lesson: The Area of a circle is equal to Pi times R (radius) squared. Pi = 3.14159 approx. Radius is 1/2 the Diameter. And to square something you multiply it by itself. All simple math. So the area of a 5" circle (125ec aperture) is equal to: 3.14159 X (2.5 X 2.5) = 19.63 square inches. The area of a 1.55" circle (center obstruction according to meade) is equal to 3.14159 X (.775 X .775) = 1.88 square inches. Thus to find the percentage of obstruction you divide the obstruction's area by the area of the Aperture of the scope times 100 (100 to put it into a percentage). I.E. : 100 x (1.88" / 19.63") = 9.57% round it off you get 9.6% Looking forward to someone straighting all these rumors out. And Please check my math. Also the 125's baffle on the secondary flares. Will this effect the ubstruction percentage? When you consider the Correcting lens is curved it might not. Don't know that much about optics and how light bends, but I'm learning. Further note on area of aperture, its concave on a Mak thus adding slightly to total area. In sort I find the S&T report very hard to believe. Folks, I may be wrong but I think things are NOT as bad as S&T and others are making it out to be. But then I'm fairly new to all this.Added later:
It's way late for me but it just hit me what S&T did, Major error and deserves a retraction or correction from S&T and maybe an apology to Meade. Ok! here it, is if you divide the diameter of the center obstruction by the diameter of the aperture i.e. 1.55 divided by 5" you get 31%. the flare of the secondary baffle looks from the pictures to be about 2". So if you divide the 2" by 5" you get 40% as S&T reported. What this says is the diameter of the center obstruction is 40% of the diameter of the aperture. This has nothing to do with the percentage of the area of the obstruction in relation to the area of the Aperture. If you do the math with the diameter at the end of the end of the baffle flare as being 2" then The ETX125-EC would be 16% obstructed, same as Nextstar. I.E. the area of the secondary mirror and its flared baffle obstructs 16% of the area of Aperture. In order to get a 39% obstruction, the secondary mirror and baffle would have to be 3.125 inches in diameter. Hope this is clear and clears things up. S&T was way, way off.
Subject: 125EC & NexStar Shootout Coming soon! Sent: Tuesday, September 14, 1999 09:17:21 From: email@example.com (jzito) I just sent my ETX-125EC back to Meade for the recommended upgrade. After I get it back I am going to meet up with a owner of a NexStar 5 to do a side-by-side comparison. Meade told me that when I get my ETX back that it should do a great job against the NexStar.I will report the results to Mike. If anyone has specific items that they want me to check on, please let me know. I expect to get my scope back by next week. Another note about the recent article in S&T about the review of the 125EC. The author is incorrect when he stated that the 125EC's central obstruction is nearly 40%. He measured the central obstruction from the bottom of the cone and not the outside. I would be interested in anyones comments on this. John Zito firstname.lastname@example.org
Subject: 90 vs 125 Sent: Tuesday, September 14, 1999 08:25:12 From: email@example.com (Van Ornum,Scott) Michael I'm considering purchasing an ETX. I understand the 125 is a 6 month back order but 90's are available. Does the 125 have any significant advantages over 90 i.e. more capabilities for sight and seeing more/farther? I'm totally a beginner and am currently researching to find the best telescope for the money and ease of operation. Any suggestions would be very helpful. Thank you for you time Sincerely Scott Van Ornum Racine, WisconsinMike here: Don't know about the 6 month waiting time but the 125 does have some additional light gathering power and resolution over the 90. But it is larger and so somewhat less convenient to set up at a moment's notice.
Subject: ETX-125 vs ETX 90 Sent: Tuesday, September 14, 1999 06:45:08 From: firstname.lastname@example.org (JK Saggese) Mike, perhaps you or one of the optical experts out there can answer a conceptual question for me. In the Sky & Telescope review of the ETX-125, the reviewer observed that the secondary mirror amounted to a 40% obstruction, due not to the diameter of the mirror itself but the baffle tube's conical shape. Now, if this is true, the relative light gathering abilities of the two scopes compare like this: A 90mm scope is 3.54 inches in diameter and has therefore 9.86 square inches of primary objective. According to Meade specs on the ETX-90EC, the secondary obstruction is only 9.6%, leaving 90.4% of the primary objective clear, or 8.91 square inches. Using the formula D=2(Area/Pi)^1/2, this net clear objective is equivalent in light gathering ability to using an unobstructed scope with a diameter of 3.37 inches. A 125mm (4.92") scope has 19.02 sq in of primary objective. A 40% secondary obstruction leaves only 60% of this primary clear, namely 11.41 sq in. D=2(Area/Pi)^1/2 results in a light-gathering equivalency of an unobstructed scope with a diameter 3.81 inches. This figure is roughly similar to a subjective estimate made by the reviewer in the S&T article (he suggested the ETX-125 was equivalent to an unobstructed three-inch scope). My question, after all that, is this: do the above calculations make any sense (did I misunderstand either the article or the role played by the secondary obstruction)? And if so, does the secondary obstruction only interfere with light gathering ability (ability to see faint objects like galaxies), or does it interfere with resolving power as well (minimum resolvable planetary features)? If both these are compromised, I'm not sure I'm a good enough observer to be able to tell much difference between the two telescopes. This would apply to the NexStar as well, I suppose, as the SCT design usually has a large secondary obstruction as well. I've not looked up what the NexStar's secondary obstruction is, however, so this last bit is purely speculation. Any comment on any of the above is welcome. Thanks, JK Saggese
Subject: Re: A New ETX-125 for my Birthday! Sent: Sunday, September 12, 1999 07:17:58 From: email@example.com (jzito) Thanks for your response to my e-mail and for your excellent site. I did find your section on astrophotography very informative. Quick question, can the Barlow 140 2x be used the the ETC-125? I bought one and used it last night to look at Saturn and Jupiter but the image appeared fuzzy. The conditions appeared to be ok for viewing. Thanks in advance for your response. John Zito firstname.lastname@example.orgMike here: I can't speak from direct experience but the concern would be whether there is enough focus travel on the ETX-125EC. If the image will focus with the Barlow then perhaps you were using too high a magnifcation. What size eyepiece were you using?
I was using the standard 26mm that came with scope. I did notice quite of bit of moisture on my lense last night too. I'm sure that didn't help. There is enough travel on the focus. I'm might have one of the bum scopes that were initially produced. I'm still checking that out. I may have an opportunity to do a side-by-side comparison of the ETX-125EC and the new NexStar. I found someone who lives nearby to just got one. I'll let you know if it works out.
Subject: Will Meade Fix "hidden" problems Sent: Saturday, September 11, 1999 19:30:07 From: email@example.com (Bill Ramsey) I just read E. Braswell's comments about his ETX125. My own ETX125 is a Meade now for collimation and image shift. The Meade technician I talked to has told me that Meade is taking a "shotgun" approach to the units shipped before August 15th that are returned. That is to say that they are completely going over each scope and making upgrades and repairs even if you have not noticed a particular flaw yet. This looks like their way of making sure that all known problems are handled at one time. When I get mine back (it has been a month today!) I will let you all know what I find. Bill
Subject: ETX125 Sent: Friday, September 10, 1999 09:01:20 From: firstname.lastname@example.org (Craig, Tom) Welcome back from what I'm sure was an excellent vacation. I'm a first-time writer but a long-time reader. Let me add my kudos for a job well done as the "official" ETX webmaster. Wanted to update everyone on my initial experiences with the 125/Autostar. I'm the guy who saw first light at the obs session that CTZERBE wrote of on 8/15. My scope did suffer the collimation problem that MEADE has acknowledged. Mind you, I live in NC so the unit saw a lot of shipping- First to the Discovery Channel Store distribution center (KY), then to the Winston-Salem store, then home to Raleigh. It was manufactured 6/18 and I got it 8/8, the day after the store received it. That first night I didn't accomplish very much since I hadn't hardly read the instructions, I am a true "beginner", and I had to keep up with my six year old daughter (who is very excited about the new scope, as well as observation sessions!) Anyhow, after that night I did have a chance to put the Autostar (revved. up to 1.2j with no troubles) through limited paces while sighting stars through Hurricane Dennis induced cloud cover. When the directions are followed, alignment is very straight forward and quickly achieved. It then located a few stars dead-center in the 26mm. The system seems to compensate perfectly for any for any backlash or play in the gears. It was able to track Arcturus (again dead-center) for 30mins +/- with no noticeable vibrations from the drives or the MEADE 883 tripod mount in the gusty winds. I don't find the drive noise to be bothersome. About the tripod. My wife gave me the tripod for my ETX90 (owned for a short time before the EC was announced) so I will stick with it for now. I don't have any problem with the accessory tray (except I need to find something to grommet the edge on the cutouts to prevent eyepiece barrel scratches). For folding the tripod, I find it easy to pull up on the tray until the legs collapse against it. At that point the tripod will stand up steadily in the corner of my living room. Although the legs are basically parallel (tips as far apart as the hinge end) I don't see that this introduces any additional transport problems from a dimensional point of view. Granted, the tripod is no cemented pier (and there are better tripods out there) it is capable of holding the scope still and the head works better than any standard pan and tilt photo head. I will probably spring for the electric focuser to fight those wiggles, all the same. After my 30 minute track, Dennis closed in for good so my eyepiece time ended. I contacted Meade for a return authorization and Paul handled it courteously. While waiting for the pre-paid shipping call tag to arrive (three business days, as promised), I downloaded SkyPro 5 demo and set the scope up indoors for a test at driving it as an "LX200". I assumed the "alignment" was good and then drove the scope with the PC and the Autostar GOTO. Got some inconsistent results with the PC. Sometimes the "slew to" command sent the scope wandering off (as indicated by the position feedback crosshair and the OTA), sometimes it went dead-on. The Autostar knew where it was pointing, however, and GOTO would take it to the desired position (as reported by both the PC and Autostar and my triangulation- granted this was all approximate: piano was east, the lampshade altitude about 30 degrees...). I'll be interested to see other reports and to try it with stars when my scope returns. Albeit brief, my experience with the scope has already been exhilarating. To find what you're looking for in the eyepiece will greatly improve the speed of my learning curve. I look forward to spending "quality time" with both my daughter and my ETX125-EC/Autostar. Still trying to think of a clever astro-closing... Tom Craig PS: I noticed that Meade has acquired a German distributor (follow the NASDAQ link at http://www.meade.com/nasdaq/index.html). Looks like they are focusing on improving their European service. Should improve the outlook for several of the folks that have posted on this site.
Subject: ETX 125 Review Sent: Friday, September 10, 1999 01:29:17 From: GSEALOHA@aol.com For your interest and the interest of others Sky &Telescope, October 1999 issue has a done a review of two models of the 125. Please note that these scopes, according to the issue, were acquired directly from Meade. I do think the acticle is worth reading. Given that on average one will typically shell out $1300 - $1400 for the telescope, tripod and Autostar, I recommend spending the $5 for this issue. As an aside, there is a 2-page spread for each scope people seemed to be interested in; the Meade ETX-125 and the Celestron Nexstar 5. Sky & Telescope, at the end of the article, does promise to do a comparison between the two in a later issue. Since, there is only about a $100 - $150 difference in price, Celestron's being the more expensive of the two, I recommend to those who have not purchased a telescope, to wait, for 2 reasons. (1) To allow time for Meade to finish correcting the errors in their scopes and to start shipping in quantity again. (2) more importantly, to be a more informed consumer and purchase the better model. When it comes to purchasing a telescope (or accessories), my father (who is even more frugal and particular than myself) and I have, over about 15 years, been very satisfied with ORION Telescopes & Binoculars. They have always seemed honest and have definitely been reliable. For those who may be aprehensive about purchasing through the mail, they offer a 30 day money back refund from date of delivery if you're not satisfied. Note: they do not sell Meade products. I did ask about the Celestron Nexstar 5. They do have it in stock and I spoke with one of the technicians who tested 2 of the scopes. He stated that he was surprised with the Nexstar 5. He said it actually worked exactly the way it ws supposed to as described in the product manual, (including the hand control go to slewing device). One final comment, please understand that I am not advocating for the Celestron product over the Meade telescope. Personally, I plan on waiting just few more months before making the purchase, simply because I want to get the most for my money and this will be by far the largest single purchase to date within this hobby. As many people have commented, one of the biggest reasons people have left this hobby is they go out and puchase a product that just does not like, the telescope ends up not getting used, and loses interest in an exciting and educational hobby. Before you make a final decision below is a quick summary of the differences between the two scopes: - Mak/Cass - easier to design and typically has better optics than a Smdt/Cass design. - Meade has a higher f ratio f/15 vs. f/10. The Meade will have a smaller field of view (tunnel vision) vs. the Celestron; but if power is an interest the Meade will be able to provide more than the Celestron. - Even though Meade can take snap shots obf objects such as the moon, it is not designed to take long exposure photographs (this is stright from Meade). The Nexstar is designed for astrophotography. - Cost; similar. - Tripod, both have designed tripods specifically for their models. The Celestron one seems to be more sturdy than the Meade counter part. - Meade has the design flaw of not being able to be used well when polar aligned, because of a short fork mount. But as Mike has stated this scope works well in the altazimuth mode. Celestron does not have this flaw. It does have a 1 arm mount vs. a fork mount which may create more vibrations than the Meade scope. If you are interested in a strictly visual scope, so far it seems that the Meade would be the better deal. If you are also interested in dabbling in photography beside visually enjoying space then the Celestron will be your best bet. Some additional items: First, there is one final design/assembly diference people may or may not be aware of between the two scopes. According to the technicians at Meade the primary lens for the ETX-125 uses adhesives and is pressed into place during assembly. In turn they stated that the ETX never requires collimation (more importantly it cannot be collimated). Now I've had an opportunity to use 2 ETX-90s (which use the same assembly techniques as the 125 model) and for both the RA and EC version, they seemed to be assembled well. I was very please with the opticle resolution of both. On the other hand the Celestron is designed to be manually collimated. So when it becomes misalligned, (and it eventually will, based on experience with an 8" Smdt/Cass model), instructions for correctling this are provided in the instruction manual. Second, if one does have problem with their scopes and does need to ship it back to the manufacturer (within the first year of purchase) both companies have similar policies/procedures for shipping it back. The difference between the two is with Meade (if I understood them correctly) does not charge for shipping and handling. On the other, Celestron requires that the consumer pays for the shipping and handling. They will quote you a price for covering these expenses when getting the return/authorization number/code. Thanks for your time!!! Geoff (anxiously awaiting more information on both scopes!) :-)
Subject: is ETX-125EC worth the Risk? Sent: Wednesday, September 8, 1999 06:15:09 From: JimBougioukos@fmr.com (Jim Bougioukos) I am a novice who uses binoculars and a borrowed Cometron. I would like to purchase a telescope that is portable, and that I will not outgrow in the near future. I have my name on a list at the local shop for an ETX-125EC, but I have been seeing a lot of unhappy owners who must return their telescopes to Meade, and it seems that many of those come back from the factory not completely repaired, requiring another return to the factory. An EXT125EC with a tripod and lenses will run over $1100, and it seems to be a gamble that you will get a unit that actually works the first time. I dont think that purchasing a telescope that costs this much should be a gamble, and I dont want to waste my money on a unit that will be forever on it's way back to the factory instead of being used in my back yard. You seem to have a lot of experience with the ETX90EC, do you think these problems are just an initial shipping problem, or a sign of a poorly designed unit. Do you think it is worth the risk to buy one? By risk, I mean buying one and not being able to use it because it is always going back to the factory. I think a portable unit like this would be great, but I think of all the comments from owners that I saw, only one said everything worked, and even that one said there were minor problems that he could live with. I dont want to sound like I am against this unit or the company, I just dont feel very confident with either one after reading from current owners. Do scopes from Celestron have as many problems as the ones from Meade? Thanks you for any advice. Jim.Mike here: We'll have to wait for user reports once Meade finishes the "shipment damage fix". Meade IS a responsible company so I have to believe they will correct the KNOWN problems. The smaller model ETX is still a joy to use and hasn't experienced the same problem as its larger brother. As to scopes from other companies, I really can't address that as my only other scope is from Edmund Scientific, purchased in the 1960s.
Subject: A New ETX-125 for my Birthday! Sent: Tuesday, September 7, 1999 14:18:33 From: email@example.com (jzito) I just received a new ETX-125 for my birthday over the weekend. I got lucky and happened to stumble across two in California two weeks ago. Even though I know there are several problems reported with the early 125's, I figured it was worth buying it and taking a chance. I contacted Meade and they told me that if I did find a problem with my scope that they would send a call tag, run it through production again, and send it back to me at no charge. They said it would take about (2) weeks. It's better than waiting 3-6 months on a waiting list. At the time of this e-mail there is probably still one left. E-mail me if anyone is interested in getting it. So far I haven't noticed any major problems with my scope. The 26mm eyepiece did have a small chip on the outer edge but it doesn't seen to effect the image quality. Meade said they would replace that too. Since I'm new at this I still have not fully checked out the optics. BTW: Has anyone ever hooked up a digital camera to an ETX? If so I'd like to know more... John firstname.lastname@example.orgMike here: Search the site for "digital" and you'll find lots of references. Many of the Moon, Sun, and Planet photos posted on my site have been done with digital cameras. Also, see the review of the Scopetronix "Digital Camera Adapter" on the Accessories - Astrophotography page.
Subject: Focus Lock??? Sent: Tuesday, September 7, 1999 08:59:44 From: KB3CNY@intergrafix.net (John J. Boyle) My new 125 exhibited this "phenomenon" also. When I couldn't get the focus to move I hopped to Mighty ETX and found the original post. I tried the fix, and the focus shaft DID pop out and correct the problem. I was about ready to send the 125 back....which I did any- way after a few trial runs. Collimation poor, focus sloppy at best, motors extremely jerky and other problems, ad nauseam. Waiting for N-5; hoping for better. Clear skies to all. John Boyle (KB3CNY@intergrafix.net) 41* 16' 36" N 075* 51' 22" W and lookin' up
Subject: N5 vs ETX5 problems Sent: Monday, September 6, 1999 10:08:12 From: email@example.com (Thierry Lombry) Here are some of the problems occuring with Celestron Nexstar and Meade ETX5 I compiled these last weeks from sessions reports, updated Sept 6,1999. Some are minors others will change your mind and your smile from :-) to ;-( Feel free to add more or delete entries as soon as corrections or accessories will be available. Thierry PROBLEMS with Nexstar 5 (N5) vs ETX5 ------------------------------------ 1. MOUNT (on their base wihout tripod) N5: excellent, no wiggle when focusing, dampen <2sec at 181x, more rigid than ETX ETX5: Wiggle even at lower magnification 2. SLEWING QUALITY N5: 1 sec of hesitation before the move, more noticable in RA ETX5: Some hesistation in RA too 3. BATTERY N5: No manual or slow motion without battery (no power no joy !) ETX5: No slow motion but manual without battery 4.MOTION: N5: excellent once aligned ETX5: A bit irregular 5. LOCKS N5: N/A ETX5: If forced, locks break 6. COLLIMATION N5: Often to recollimate at 1st reception ETX5 : N/A 7. FOCUS SHIFT N5 : very slight at 181x even after collimation ETX5: No more or very low focus shift 8.HAND CONTROLLER DISPLAY N5 : Perfect, can be read in daytime ETX5 : Very problematic even at dusk 9. ORIENTATION N5 : Don't warn for object below the horizon. Choose the long way to reach an object east of another ETX 5 : ? 10. MISCELLANEOUS N5 :Rubber feet don't hold, loose screw from gear ETX 5 : firware bugged 11. LOOK N5 : excellent, feeling of solid metal (even if 50 plastic) but sometimes scares near corrector lens. ETX5 : feeling of light plastic 12. ASTROPHOTOGRAPHY N5 : Can do it states Celestron ! ETX5 : Not recommended by Meade... NB. The true ? Both can do instantaneous pictures (moon, planets, sun) but the tracking is a another story for longer exposures (deep sky). GREAT IDEAS for N5 : Intuitive GOTO with easy "Undo" button Programmable backlash Laser finder Easy and accurate Autoalign Battery place (top) Use standard accessories of Celestron GREAT IDEAS for ETX 5: Mak design (great optic, very few collimation need) Autostar + hand controller 2 arms BAD CHOICES for N5 : SCT optic (collimation & central obstruction) 1 arm (even if robust an extremely stable) No electric focusing (yet) GOTO cord plug falls down Use of AA batteries No piggyback (yet) except OEM brackets No The Sky interface (yet) nor tested in the field BAD CHOICES for ETX 5: Obstruction introduced by the baffle (accordind S&T, similar to N5) No easy "Undo" with Autostar Battery place (from bottom) Mirror flip Small finder Too many alignment methods Use of AA batteries Use some of standard accessories of Meade No piggyback except OEM backets No focal reducer (yet)
Subject: S&T review of ETX5 and comments Sent: Thursday, September 2, 1999 02:07:01 From: firstname.lastname@example.org (Thierry Lombry) Here is an extract from sci.astro.amateur. Note I confirm that many sesion reports from recent buyers confirm the fact the tracking IOS irregular... Thierry Re: S&T reviews ETX-125 Date: 1999/09/01 Author: Phillip Hosey (email@example.com) Posting History sensory surfer wrote in message firstname.lastname@example.org>... "Michael Covington" (email@example.com) wrote: Well... I congratulate Sky and Telescope for their courage. In the issue that I received yesterday, they reviewed the ETX-125 unfavorably. After saying as many nice things about it as they could, they pointed out that the central obstruction is unusually large for a Mak, the drive is so irregular that they had to turn it off to resolve Epsilon Lyrae (the close doubles, that is),
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