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I would like to start out by thanking Dr Kron, the director for coming up with the idea of making the historic 40" available to amateurs for a week as part of the centennial celebration and John Briggs, staff member for making it happen and Dawn Mueller of NIU for inviting me.
Still not quite sure whether there is a god but I won't hold it against him if there is. Lots of folks did a lot of praying for clear skies and it looked pretty hopeless on the drive up. However, by the time it was dark enough to see Mars, an opening appeared and by the time we were ready to move on to something else, there was not a cloud in the sky. Unfortunately, the prayers did not include seeing conditions.
Under any conditions, it would have been the thrill of a lifetime. Just to lean into that massive piece of machinery and move it around was a real experience. I fell in love with astronomy as a small boy here. We were fishing on Lake Geneva and when it started to rain, my dad rowed over there and we took the tour. I was hooked for life. In later life, I sold a piece of equipment to them and was invited to spend a night with the 40" during an opposition of Mars but was skunked by the weather. So, this was the culmination of a lifetime dream and what a dream it was. I am still walking on air.
Now for the bad news. We all read about and some of us have experience with the effect of seeing on larger scopes. We have even heard people being accused of using bad seeing as an excuse for bad optics. However, this lesson came like a hammer blow to me. I have looked at Mars every clear night during the current opposition with both my 10" and 16" scopes and have a good feel for what can be expected around here. (Yerkes is only about 40 miles north of me) I have been unable to see any detail on Mars for the last two weeks and was prepared for less than spectacular views but hoped the 40" and the magic of a refractor would more than make up for the poor seeing. Well, can you say "blob"? The only "detail" I could claim was the waning gibbous shape. We "stopped it down" to.. ha ha 30" but the only difference I could see was a lessening of the chromatic aberration. It should be noted that the hemisphere of Mars facing Earth at the time was one lacking in large conspicuous features. The Central Meridian was near 160 degrees and about looking at the Pacific Ocean from Mars.
We spent most of the night with a 55mm eyepiece which produced a magnification of about 320x. After everyone had a good look, yours truly (the designated photographer) installed my 4 x 5 Astro Camera in the business end and took a photo. The eyepiece in the focus plate is 17 mm and with the 2x focal extender, I was looking at about 2000x. A real experience, I must say. A bit like a furry pumpkin.
The camera worked as if it was designed for the scope but I didn't want to interfere with the precious observing time of the group so I put it all into one photo. I used a dark red filter, a 2x focal expander providing an EFL of 1520 ft to produce an image about 1.8mm on the film. The exposure was one second on unhypered Techpan and we used the shutter built into the back of the scope. I was a little nervous using this shutter as I was unfamiliar with its function but John Briggs insisted that it be my picture and work it out.
The end result is probably a bit boring to a Mars aficionado and a poor second to what I have taken with my 10" under better conditions, but it is a photo I will treasure for life. It will be featured on next week's Photo of the Week along with a shot of the scope.
I should also point out that I would not have a picture were in not for the flexibility of the 4 x 5 AstroCamera. I was prepared to use 35 mm so I could take lots of shots in rapid sequence and brought the 4 x 5 as a back up. Turns out that you can crank the back end of the scope out several feet but we were within one inch of all the way in and anyone who has ever tried to use a 35mm camera on a typical scope knows what that means.
One interesting feature of the scope is the incredible depth of focus. Several times while trying to find the best focus, I found myself with the eyepiece in my hand. I didn't even bother with the vacuum hold down in the film holder. It couldn't possibly care about a few thousandths film shift. It seemed more like about an inch before it made much difference.
After spending about an hour on Mars, we moved on to M53 and M3, both globulars and again, I could not believe what the seeing was doing. There was a real eyeful of stars but they were fuzzballs not points and it gave me the impression that it was out of focus, no matter what I did. I have a sneaking suspicion that much of the seeing problem was dome and slit related as it was opened when we came in and there was a very strong draft all night.
I was a bit disappointed in the view of M53 but as I had never seen it before, I looked at it a few nights later with my scopes. I am now very impressed. It is barely resolveable even in my 16" and it looked about like M3 in my 10". I did not realize how remote and small it it.
The last object we looked at was M51 and it was an amazing sight. It took awhile to understand what I was looking at because at 320x, it filled the field. It was not dazzling bright but the structure visible was awesome and not effected much by seeing. The most conspicuous feature was a glowing circle of light about half the total diameter, concentric with the center. A spiral arm I could actually look at and study in detail. No averted vision, no popping in and out, it was conspicuous. Wow!
As I am typing this, it is totally overcast, has been and will be for several days. I can't help but wonder what the group of amateurs poking around the observatory right now think about the god thing.
The exposure was one second on unhypered TechPan and printed on color paper through appropriate filters to restore the filtered color.
She really does have an upper lip. There is some wierd shadow there.
The exposure was a half second on unhypered TechPan and printed the same way. .
All photos taken with the...JSP ASTROCAMERA
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