Last updated: 16 August 2009

First Light with the ETX-LS

Shortly before sunset on 15 August 2009, I set up the ETX-LS 6" ACF in front of my SkyShed POD:


This location provided good sky access with no large metal surfaces nearby. As the ETX-LS uses GPS and has magnetic sensors, both of these requirements are important. (My concrete pad uses fiber and has no rebar.)

Moving the ETX-LS 6" on the tripod is a little more difficult than previous ETX models, even the heavy ETX-125. There is one fork arm so the weight distribution is a somewhat uneven. There is a handle at the top of the fork arm, but that works best by itself when the ETX is removed from the tripod. To carry the ETX-LS while still on the tripod, I found it best to pick it up by the bottom of the base opposite the fork arm using one hand and use the fork arm handle with my other hand as leverage. Your height and the height of the tripod will dictate how best to pick it up.

In the box with the telescope there is a CD-ROM with the full version of AutoStar Suite (for Windows) and a PDF of the manual. The only printed instructions in the box is a large Quick Start Guide. Since many users will not read the manual (although I downloaded the manual from Meade's web site and read it several days ago), I decided to see if the Quick Start Guide was adequate to actually start using the ETX-LS. Set up was done according to the Guide, so that was OK. Alignment, per the Guide, was started by just turning on the power switch. There was no mention of a HOME position or unlocking any locks (since there are none). There are no hard stops (unlike the ETX-90, -105, -125 models) as the entire base/fork arm rotates. So I just left the OTA where I had put it (raised slightly above horizontal and pointed south (just because). The ETX-LS uses 8 C-cell batteries (not supplied). Alternatively, you can use an AC Adapter (no mention of the amperage requirement) or an external 12VDC power supply using the Meade #607 DC cord. I'll try the power alternatives at a future time but for this first light I used the internal batteries. An hour after sunset it was dark enough to see lots of stars, so I powered on the ETX-LS. I didn't do any calibrations or drive training as the manual implied those would probably not be needed and they were not mentioned in the Quick Start Guide.

When the ETX-LS is powered on for the first time, you get to hear some introductory audio through the built-in speaker in the ETX-LS base. I let that play. It lasted about 3 minutes and it can be turned off or skipped entirely on subsequent power ups. I did discover that having the audio describe what the ETX-LS is doing was useful and meant that I could just sit in a chair and not monitor the AutoStar display for status. After the intro audio, a GPS fix was taken. That only took a few seconds, which surprised me as I expected it to take longer. But it seemed to work (as I found out later). The ETX-LS then went through the process of finding North and level. That took a little less than 4 minutes.

Once the North and level steps were finished, the star alignment was begun. Unlike other AutoStar models, the current AutoStar III software (version 1.07) doesn't have a menu option to turn off the display of the alignment star names; but since I prefer the star names to be displayed, that was OK with me. The first alignment star that the AutoStar III chose was Arcturus, which was about 40 degrees above the western horizon. Unfortunately, when the ETX-LS finished slewing it was pointed near the horizon instead of upwards. The audio said that the camera was now searching for the star. However, since it was so far off, the AutoStar gave up after a few seconds and picked a second star. The audio said that the star was obscured. There was no mention of such a large pointing error. The second star was Deneb but the OTA ended up pointed almost at Altair. Again, the camera couldn't find the star. It then tried Alkaid, but was about 30 degrees too low. It picked a fourth star but obviously Auto Align was not going to work. I decided to abort the alignment so that I could check the various settings. Before I could do that, the audio said it was going to pick another (5th) star, but before it displayed the star name the AutoStar III displayed "Align Faile" (without the "d") and said to check the site.

I pressed the MODE key to display the SCOPE INFO. The local time shown was one hour later than the real local time (we don't observe Daylight Time here). I changed the time zone in the Preferences and did an Auto Align again (without powering off first). It again picked Arturus but like before was pointing about 40 degrees too low. I aborted the alignment and checked the settings again. This time the date displayed 16 August instead of 15 August (but that wasn't enough to cause the pointing error). The Latitude and Longitude displayed were correct but the "NEAR TO" location was about 100 miles to the south! Again, not enough to cause the pointing error but still odd. I decided to start from scratch; I powered the ETX-LS off and then back on to let it go through its steps using the correct time zone. Same pointing error with Arcturus.

I turned off the GPS and selected to do a manual 2 star alignment. It asked for a confirmation of the date and time (which were correct). The ETX-LS went through the North and level steps and then slewed to where it thought Arcturus should be. But again, it was off by 40 degrees too low. I centered the star. The ETX-LS then slewed to Kocab, which was placed close to the red-dot in the finderscope. I centered it and received a "Good Alignment" on the AutoStar display. I then did a GOTO Jupiter. Unfortunately, it missed Jupiter by about 5 degrees. I centered Jupiter and switched to a 9.7mm eyepiece (157x). Jupiter and its four moons were really nice, even though Jupiter was still low in the sky. I then did a GOTO Antares; it missed by a few degrees. I centered Antares and did a SYNC. I then did a GOTO to M4, which was only a few degrees away; it was placed about half-way to the edge of the FOV in the 26mm eyepiece (58X). I expected it to be closer to the center given the SYNC on Antares. At this point I decided to do the drive calibrations and see if that improved the alignment and GOTOs.

Drive calibrations are the same as drive training in older AutoStar telescopes. I used Polaris, which is an option suggested by the ETX-LS. I then cycled the ETX-LS power and did a manual 2 star alignment. This time it was about 15 degrees too low for Arcturus. I aborted the alignment. I turned the GPS back on and set the time zone to be "auto". I cycled the power and let the ETX-LS do its Auto Align. It picked Altair as the first star; unfortunately, the ETX-LS thought it was located in the tail of Scorpius! The camera gave up and the ETX-LS slewed to Alkaid; it was about 15 degrees too low. I aborted the alignment and checked the settings. Again, the time was off by an hour. So I changed it back to the correct time zone and cycled the power once again. Again it picked Altair during the Auto Align but pointed towards the tail of Scorpius. I aborted the alignment.

By this point I was getting rather frustrated. I began to wonder if the metal legs of my observing chair and table were affecting the sensors in the ETX-LS. They were about 3' from the telescope. I moved the telescope 10' away from the POD, chair, and table, and tried an Auto Align again. It still thought Altair was in the tail of Scorpius. I gave up.

Even I couldn't get the ETX-LS to align properly using Auto Align or a manual 2 star alignment, I still decided to check out the optics. I manually slewed it to M31, the Great Galaxy in Andromeda. I switched to a 40mm (38X) eyepiece. M31 and both its companion galaxies appeared in the same FOV! Stars were good all the way to the edge of the field.

I did a "star test". Collimation was excellent. And stars were nice pinpoints to the edge of the 26mm (58X) field-of-view. The ETX-LS 6" is a faster optical system than the ETX-90, ETX-105, and ETX-125. It is an f/10 system with a focal length of 1524mm. The larger aperture combined with a shorter focal ratio means that objects will appear brighter than they do in the "classic" ETX models. And of course, having UHTC is a plus (and non-optional).

Focusing is done using a large focus knob. Previous ETX models have all had rather small knobs that were difficult to use, especially by users with large hands or while wearing gloves. The ETX-LS knob is essentially the same as that used on the LX90 and LX200 telescopes and is much easier to grasp.

When I first learned of a new ETX model in mid-2008, I was concerned about it having only a single fork arm. I was assured that it would not be an issue. Now that I've experienced the new ETX, that concern is gone. The single fork arm works well and provides sufficient stability to the OTA.

The alignment problems I experienced during this first light reminded me of the pointing errors I had with the (now discontinued) mySKY. Could there be a common problem?

One point about the red-dot finderscope. Unlike the finderscope on the ETX Premier Edition LNT module, the ETX-LS finderscope is powered a separate battery and not the ETX-LS main power. This means you have to turn it on and off. So, remember to turn it off when you finish using the ETX-LS.

The ETX-LS will go through batteries quickly. I started the night with fresh ones. But three hours later the battery power was down to 73%. Of course, I did try more alignments than would be normal. For extended use, I recommend using AC or an external DC power supply.

I'll report on using the built-in imager for wide field astrophotography in a future report. First, I need to get a mini SD card or micro SD card. No specific volume size is mentioned in the manual. Also, for best results when imaging, it will be necessary to hook up an external monitor. And, using an external monitor will allow display of starmaps and AutoStar menus. The external monitor source is composite video. Now where is that old Apple II color monitor I have???

I have contacted Meade regarding the alignment problems I experienced. I'll update this report when I learn more from them. Stay tuned...

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