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What Became of That Big Astrograph?
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What Became of That Big Astrograph?
By
Patrick Stevenson
Tucson, Arizona
Finished Product
In short, it fell victim to my age and physical condition! But first it got to go outside and play some. This story will tell the tale of the ultimate fate of the astrograph.
Ready to Run
There were two characteristics of the monster. First, it was really big and cumbersome. Second, it weighed forty-four pounds stripped. Not difficult to imagine where it was going.
I decided that there was no way I was going to put that much work into a project of that magnitude and never give it a chance to fly, so I set about finding a way to use the creature without the task of moving it around. An observatory was a likely solution. Unfortunately I live on a VA pension and Social Security. Even if I were capable of tackling another task of that magnitude, I couldn’t afford it. You can check the back articles until you fine one about Fairhavens 1 that was a 10x12 roll-off a few years ago to see that I at least KNOW what to do. Current circumstances simply did not allow that solution.
I had a CGX mount that was marginal for the weight but I figured if I balanced it well enough that would suffice. Of course I had to include the weight of the coma corrector, camera, guide scope and I think some other stuff that easily surpassed the specified maximum weight for the mount. Frankly, that never even crossed my mind until after I was done with the scope.
Concrete Block Floor
I sat in the back yard for a few hours looking at a pile of scrap from another small roll-off that I built when it became apparent that the big scope would not fit.
Original Observatory too small
Clearly the traditional observatory was not in the works so I conjured up the idea that I could make a roll-off observatory by using the hardware from the former roll-off roof. With a budget that wasn’t worth documenting I constructed a frame at ground level supported on cinder block top caps. I then attached the aluminum rails that came from the top of the previous building.
Using all the scrap lumber that would work I built a nearly square 5x5x5 shed with the steel “V” wheels off of the old roof. I did have to buy new T111 3/8ths thick siding to add strength to the structure. The previous structure had a subfloor with holes in the floor for the tripod legs so once the subfloor was gone I just had pea gravel.
I used 12”x12” concrete blocks to set the tripod legs on that worked well for that particular purpose. Did you ever try to work on pea gravel in the dark? All I could think of was the broken hip I was going to earn by trying to walk on four inches of pea gravel in the dark.
Very unstable footing
I live in a leased home so I was restricted from doing anything permanent like a concrete slab. Again, I sat and pondered. Given some time I remembered a patio deck that I built some thirty or so years ago. It is a simple technique. I leveled the area that I thought would be adequate, laid cinder block fence caps in an attractive pattern (right on top of the pea gravel). Once the blocks were in place, I dumped a couple of sacks of concrete on them, spread it around with a broom until all the spaces between the blocks were filled with the powder. I then spent some time with the garden hose with the nozzle set on spray an wet the whole surface down until the concrete powder was thoroughly soaked. By the next day I had a monolithic deck that functioned as well as a concrete slab.
More secure footing
The final result was that I had a shed large enough to contain the mount and telescope when rolled over them. Of course, the scope had to be parked in a contorted position to fit. I had the solution to getting the mount and telescope into a condition that they would be protected from the weather, and hot Arizona sun, simply by parking the scope and rolling the “box” over it.
Parked and enclosed in shed
Now that I document this project it doesn’t seem that hard or complicated. I think, to a large extent, that is because of my failing memory; and my wife, who watched from a safe distance, and had an entirely different opinion. I think it may have been based in part by the number of Tylenol bottles I went through.
To my feigned strutting, and utter amazement, it actually worked quite well. I was now able to really test the new design on a tracking mount that surprisingly handled the weight just fine. One would think with every problem solved the rest would be simple. Not so.
That monster remained a monster. Had I been thirty years younger, and much stronger, it would have been fine. It’s amazing how much muscle was still required to manage something that big and heavy. With not much regret I decided that retreat was the only way out. I decided it was time to downsize to something that I could handle more easily. My plan was to move to a relatively small refractor on a Celestron AVX mount .
So, here I am now with a new Explore Scientific ED 102 Triplet on an AVX mount. The rig is fully populated with ASI cameras, ASIair Plus, etc.
Downsized and much lighter
So, what finally became of the monster? In one of my brighter moments I had saved all the parts from my donor scope. I de-populated the astrograph and re constructed a 10” f/4 newt that sold on Cloudy Nights in one day. All is gone now except for one thing. Anybody out there interested in a 48” aluminum tube?
Back to donor scope configuration
In summary. I’m glad I did it, although I wouldn’t again. I am pleased with the results and have many fond memories…… Yeah, I’d do it again.
EPILOG
The primary intent of this build was to determine if mechanical changes alone could resolve the problem of ambient light pollution without the utilization of various filters designed to block man-made artificial light which, by themselves alone, tend to block natural signal that then require excessive post-processing to at least appear to add such signal back into the final image. In short, produce entirely natural image quality without the use of artificial signal modification. And, if so, was it worth the extra engineering modifications? In a word, yes. And to a large extent, no. It was effective, but at the same time, not worth the cost of implementation. The final test would be to compare an image image both with and without these mechanical implementations.
NGC2403 With no modifcations:
NGC2403 With modifications:
The difference is clear. The ambient light pollution can be removed without the use of filters.
I have decided that after I heal up from this one it will most likely be my last project. At least until the next one. Although I do have some thoughts about collimating an RC.......
- Bob Campbell, Mert, jkevn and 28 others like this
22 Comments
Very interesting read and the trials and tribulations you experienced on the way.and I take my hat off to you for not giving up at the first hurdle.it also shows when there’s a will there always a way to the initial problem.
Another informative and entertaining missive. The proof is in the pudding, and the contrast (no pun) between before and after images is quite striking.
Thanks very much for sharing!
Bob
Having a longer tube eliminates any nearby light intruding into the image but it does nothing regarding your local sky light pollution level. Its also a fairly easy test to make as flats won't calibrate if you have intruding lights.
So Pat's before and after seems to suggest that his LP environment was mostly local lighting, the light dome was not all that intrusive.
"also a fairly easy test to make as flats won't calibrate if you have intruding lights."
That is my situation to a 'T'. I do use flats, which cured vignetting (I don't have motes so far) , but I have higher order gradients that I simply live with in the EAA world. My patience in data collection and post-processing is not sufficient, nor is the quality of my setup to pursue AP.
Bob
Thanks, Bob. I think you are one of the few that can appreciate the headaches (literal) that come with something like this. Truly, had I been a few decades younger I would have stuck with this scope for imaging. I did quite a few other images without filters that came out beautifully. Unfortunately, this was the only one that was actually shot for a comparison.
To be perfectly honest, had I known of the physical pain that came with moving all of the component parts around along with "test" fitting, I probably wouldn't have finished. My wife thinks it is actually some kind of psychological obsession. I think she may be right!
The things we do for love...
Thank you for sharing…experiences like yours are driving some of the decisions I’m making now as I “simplify” my collection of goodies with an eye to the future.
Fortunately, the electronic aided goodies available now help us to make more out of the reduced aperture that our aging bodies seem to mandate. It’s not “all” bad.
Bob
As the saying goes, "Love is blind."
Great Read! As a pensioner of a "certain age" I could immediately identify with your story. I've got an observatory that's ready to go at a moments notice, but as the mileage rolls up on my airframe I think of what it would be like to downsize at times. Enjoyed the read Sir!
This was a 10 inch "monster"? Why was the Newt you built from it not itself a monster? The 2 galaxy photos were same scope with and without the roll-off structure? Under otherwise identical sky conditions (moon phase etc)?
I really liked reading this article so thank you for putting it together and sharing your experience. I'm on a limited budget, have an old monster scope I can't seem to part with (yet), have a less than desire back with my age and am attempting to bring to present-day mediocre performance. So, I can relate to your story on multiple levels. Valliant attempts are always honorable if not successful...
The donor scope was a 10" f/4 standard Newtonian built for visual as much as imaging. The astropraph had a number of design and engineering differences that made it only practical for imaging. The intent of the changes in design and engineering was to eradicate ambient light pollution without the use of specialized filters designed to eliminate man-made light pollution. It was successful. Of course, it weighed about fifteen pounds more and was a foot longer than the donor. Were I twenty years younger that would not have made a difference, but at 76 that extra weight and size were a major factor. The comparison pictures had nothing to do with an observatory structure, nor the phase of the moon. Read the original article https://www.cloudyni...strograph-r3365 to get a proper description of the differences.
This project was a "hobby" project left over from my time at Steward Observatory Mirror Lab. I never really planned on using the beast, only to prove that light filters were not always necessary. My suggestion is to look at what I ended up with for an old guy with a bad back. It's hard to beat a small refractor (17lbs) on a 20lb mount. Maybe I can't image mag 13 galaxies, but nebulae are still pretty.
Well put. Sounds like you have an aviation background. My military career was primarily as Aircrew on a P3 Orion. I have a few articles that I wrote about my earlier observatories and I miss them, but I'm still glad I finally bit the bullet and downsized. Lots of fun with little pain. https://www.cloudyni...the-story-r3317
This is an article on the first observatory I built.
When did you work at Steward? So, the mirror lab was at the university, correct? I had a friend working there in the 90s on the top of the mountain. He headed the maintenance crew.
After a thirty-year military career I tried the standard Law Enforcement track which proved toxic to me. I applied for a job at the Mirror Lab as a "gofor" but was told that I was overqualified due to my education and experience in the military. I wouldn't take "no" for an answer and finally dug my way into the job. Unlike the other techs working there I read, studied, questioned everyone that would listen. Within eighteen months I was the Supervisor of the Polishing Lab at Steward. I was there for another eight years and worked on five large telescope mirrors to include the GMT, LSST, LBT and MMT. Best job I ever had in my whole life. I finally retired to my acreage in the Arizona desert and my own small observatory where I continued my projects. That all started in 2002 until I retired in 2012. If it were not for medical problems I would be there still at 76.
And I thought I had problems that only a scope buggy might cure! You have certainly climbed the mountain with all your efforts. Well, I for one am glad I have avoided astrophotography and have kept my setup simple. For me, the inspiration was when my dad got a used old Edmund Scientific 3" refractor in about 1966. It was all about the visual, the eyecandy. That, and learning the scope and its ways has always been enough for me. I mean no 'dis to any; let's just say, "know thyself."
Well said, indeed!
Bob
Very interesting. I have the exact same result. After taking on the project and working on it for what seemed to be forever, I am going to dismantle it and sell the parts and pieces starting shortly. It is simply too heavy for me personally and I am probably going to replace it with a refractor. It appears that we took the same path and ended up in the same place.