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"First Light" Full Aperture Solar Filter
Posted: 30 October 2011

On Friday, 28 October, I received a full aperture white light solar filter for the 8" LX200-ACF from Orion Telescopes and Binoculars. The filter is coated glass and has three retaining screws. The package includes a 8.5"x11" paper of instructions, a cleaning cloth, and some felt pads if needed (I didn't).


Of course, the sky was cloudy so there was no solar observing. The filter was "compensation" for contributing some iPhone photos to Orion, showcasing the MX-1, which is now available and improved from Orion as the "SteadyPix Telescope Photo Adapter for iPhone" ($60). The sky cleared on Sunday, 30 October, so I opened the observatory at 1027 MST, 78°F. I mounted the solar filter on the 8" LX200-ACF, as well as the PST (Personal Solar Telescope):


At 1043 MST, I began solar observing, first with the PST and 12.5mm eyepiece (32X). There were several small prominences and filaments visible. There was one very nice sunspot group visible in the PST. I then had "first light" with the Orion filter, with a 26mm eyepiece (77X). Wow! What a view! The sun's image was SO MUCH BRIGHTER and with SHARPER DETAILS than what I had with the white light filter from my ETX-90RA attached to the 8" telescope. Of course, with the ETX filter, the 8" aperture was stopped down to about 3", so it was not surprising that it provided a dim view.

I then set up for iPhone afocal imaging with the white light solar filter. This image was taken with the iPhone 4, MX-1 afocal adapter, and the camera app, 26mm eyepiece.


Several sunspots are visible in the image. Here is another iPhone, afocal 26mm eyepiece, image, but desaturated and cropped to just show the large sunspot:


Next, I did some more solar observing, this time with the 15mm (133X), 9.7mm (206X), and 5.5mm (364X) eyepieces. Although seeing was not very good, the details visible through the full aperture solar filter were very good at times, even at the higher magnifications. Next, I set up for D7000 DSLR imaging. I unmounted the PST, as it was in the way of the DSLR camera body. This is a desaturated, 1/640sec, ISO 500, prime focus image:


And this is a prime focus + 3X TeleXtender, 1/320sec, ISO 1000, desaturated and cropped image:


I ended imaging at 1135 MST. Took a final look at the sun at 77X and then began closing the observatory. But I am very happy with the new solar filter and I look forward to many more days of solar observing with it.

Closed the observatory at 1150 MST, 88°F.

In a previous report, I mentioned trying to see a "duck" in M11 (Wild Duck Cluster). Steve Waldee read that and commented:

The appellation "wild duck cluster" is derived from an old, respected deep sky work for amateurs: "The Bedford Catalogue" by Admiral W. H. Smyth (reprinted in paperback by Dover.) Smyth used a very high quality 6 inch refractor and his perceptions were very acute, establishing the general characteristics of numerous objects that are today accepted by many visual observers. To him, Messier 11 resembled "a flight of wild ducks"; you are not going to 'see a duck' as it were. Your preference for a cat with bushy tail might be perfectly sensible, but I can't say that I've noticed that--next time I look, I'll bear this in mind.

Unquestionably, my own finest view of the object was at my site in the mountains, south of San Jose, at 3400 feet elevation, on the side of a chasm that drops thousands of feet into the valley (at a place which often boasts superbly steady laminar air.) On June 20, 2007, using a 10 inch reflector, I was astounded at the amazing stillness of the star images, of perfect pinpoint refractor quality (seeing was, therefore, Pickering 10!) and I wrote in my logbook that M-11 had a "a refractor-like lapidary display: a single overwhelmingly bright radiant point set at the edge of a fan-shape of flawless crystals, like a celestial queen's incomparable jewelry." My own nature as an observer does not favor perceptions of shapes or angles or connecting the dots to perceive patterns, but rather what I guess I could term 'holistic conceptions'. It often takes me many tries to sense star patterns that are so very obvious to others!

Other Site news: I have added image date and exposure data to the Photos pages. I hope this helps others in doing astrophotography.


Go to the previous report.

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