Another Cave 12.5" reporting aboard, with pictures
Posted 16 November 2012 - 07:37 PM
:jump:FIRST LIGHT!!! (6:10 pm)
First lighted in my driveway, with several porchlights on from neighbors, and light pollution from DC to the north...that's the down side. On the good side, temperature's in the high 40's, there's no wind, and the sky's clear with steady seeing. Completed a rough collimation this afternoon. Using a Celestron 1.25" 25mm orthoscopic (so, about 75X)
Bob Midiri bet me that I would have a great mirror...well, Bob, you won the bet...my first impression is that the optics are AWESOME!
I love my orange tube C8 from 1976, but the Cave blows it away...the starfields sharply focus to a mass of pinpoints, and the field is much brighter and more populated (larger aperture wins here, naturally). The rotating tube is a great feature, but I'm still using a two-step kitchen stepladder to get to the eyepiece at elevations above 40 degrees (no problem there).
Went for easy stuff to begin with...
Vega: Like looking at a blue white acetylene lamp, with four delicate diffraction spikes from the spider...I can't get over the number of faint stars in perfect focus I can see in the same field!
Albireo: the VIVID orange and blue of this double in the Cave is a new experience for me, and I've observed this double hundreds of times over the last 37 years.
Ring Nebula (M57): First time I've not had to use averted vision to get the full impression of this planetary. Again, all these star fields are so much more populated than I was expecting...it's great!
Mount's working great (no wind obviously helps there). Next stop...Jupiter (have to wait about 2 1/2 hours for it to clear the tree in my yard). Moon was behind the western treeline by the time I was set up...gives me something to look forward to tomorrow!
Thanks again to all of you that helped me get the scope ready to go back in service...what a great group you are! Couldn't have done it without your help!
Posted 16 November 2012 - 08:55 PM
I think I need a taller step ladder for my 12.5". One with 4 steps and a rail, not just 3. I don't like being that close to the top of the 3-stepper. And at the zenith, I still can't reach the eyepiece with it.
We're socked in, probably for the whole weekend.
Posted 16 November 2012 - 09:32 PM
Tim's right, be careful when you feast your eyes upon Jupiter when you're 2 feet off the ground.
Posted 16 November 2012 - 09:46 PM
Back in the 70's, when I lived in Springfield, VA, the light pollution from DC and the Alexandria/Arlington counties was just encroaching the area, but now it's all over. That's unfortunate, but with 12.5" of light gathering power, you should be able to bring in lots of stellar detail that an 8" would not give. A light pollution filter might help as well.
On the Horsetrail Cave at f/7.5, I usually have to use an 8-foot ladder and go up to the 3rd or 4th step to get to the viewfinder and focuser - One of these days I'm going to make an observing stand similar to aircraft maintenance stands I know from way back when I worked on military aircraft that are easy to move around and have rails for safety.
Unfortunately, I still have eyeball problems with central serous retinopathy and haven't done much observing for the past 6 months. I can barely see 3rd magnitude stars at this point and everything is distorted, so for now, it's more like tinkering with scopes than looking through them. But, it's supposed to go away and my vision is supposed to get better after a while!
With years of looking through scopes, it's nice to roll out the Cave's and just enjoy them, no matter what you see
Posted 16 November 2012 - 10:11 PM
Congratulations on first light!!I have the same issues as you,Tim and Dan with the 12.5 inch.Access. We should put our heads together on an observing platform design.Sounds like Dan has some good ideas!!
Posted 16 November 2012 - 10:44 PM
For Hatch Observatory, where I have my Nexstar 925GPS mounted in the roof of my house, I needed a platform at comfortable height below the scope that could be rolled away or dismantled and stored without taking up a lot of space. I ended up with two moderate sized rolling scaffolds from Step-Up Scaffolds. I can take the metal deck planks off and fold the frame up and stow both of them in my "secret hideaway" behind the walls, turning the attic space into an entertainment room for the fam.
Posted 16 November 2012 - 11:22 PM
First light (phase 2) was Jupiter. I took your advice about not falling off the stepstool by substituting my "Little Giant" stepladder for it.
Observing Jupiter...I boosted up to my 15mm ortho EP for this...approximately 130X. Jupiter looked like a globe, vice the disk I'm used to seeing with the C8. There was definitely an impression of depth to the scene...both for Jupiter's disk, and the relative positions of Jupiter and the Galilean moons(all four of which were preceding Jupiter through the field of view). As for Jupiter itself, I saw detail similar to Dan's (Datapanic's) shots of Jupiter using the Horsetrail Cave...three reddish detailed belts with eddies and texture...two tinted polar regions, one of which had a distinctive greenish-gray tint to it...the best viewing of Jupiter I've ever been fortunate enough to experience.
And, to top it off, I did NOT fall off the stepladder! (Success across the board!)
More to follow...but this "first light" was all I hoped it would be!
Posted 16 November 2012 - 11:39 PM
Posted 17 November 2012 - 09:02 AM
Posted 17 November 2012 - 07:06 PM
That is a great first light report. I'm glad to be of help and even happier that everything is working great. It sounds like you have a superb mirror!
Congratulations. I'm always glad to see a classic scope preserved and things put back on it the way it was originally, especially a Cave!
Posted 22 November 2012 - 02:26 AM
Up a little bit late tonight after observing with the 12.5" for over three hours, and am waiting for the ibuprofen to kick in (running up and down the ladder, and wrestling the tube from NE (Jupiter) to SW (Moon) have my back acting up a bit -- but I was so excited during the session that I didn't notice anything until I restowed the scope in my garage).
Conditions were OK...clear sky, with the same porchlights and skyglow I had during first light. Temps in the low 40s...no wind, but the atmosphere was "boiling" a lot, with periodic short lulls of good viewing. Main viewing was the Moon, in the Mare Imbrium area, with periodic side trips to Jupiter and the Pleiades.
Cutting to the chase...I have never seen the Moon through a telescope the way I saw it tonight. Used my Celestron 1.25" Plossls (from 6MM (310X) to 40MM (46X)). Looking at the triad of big craters in Imbrium (Autolycus, Aristillus and Archimedes) and their surroundings was truly a new experience. I had never seen the subtle swelling and rolling of Imbrium's surface before...or the dozens of small to tiny craters surrounding the "big three". The twin peaks west of Archimedes stood out like tiny needles, with exquisitely thin twin shadows stretching further westward towards the terminator. Unbelievable, even with the "boiling"...beyond unbelievable when the boiling ceased.
Following the southern mountain boundary of Imbrium west towards the terminator, I happened upon Copernicus...and went no farther for a long time. Copernicus was on the terminator, so I knew the vertical relief would appear exaggerated...but what I saw stunned me. The closest I can come to a description is that it looked like a vast version of the ruined Roman Colosseum with the closely concentric walls towering into sunlight; the interior obscured. Further to the south, I viewed a major crater with half of its floor in bright sunlight, bisected by a ridge...the other half (beyond the ridge) in black shadow. I could go on with what I saw further to the south, but you've seen it yourselves...I'd just be "piling on" superlatives.
Sounds horrifying to say this, but Jupiter (although great) was merely an afterthought tonight.
I ended up holding an impromptu star party/viewing session tonight for 5 or 6 of my neighbors who noted a BIG white tube pointing skyward in my driveway...showed them the Moon and Jupiter...for most, it was their first look through a telescope, and they were uniformly "blown away". (I should add that several of the porchlights went out after my neighbors left. ) May end up being the first meeting of the "cul-de-sac" astronomy club!
Tried the refurbished drive for the first time tonight, with a rough alignment on Polaris...worked well enough to keep the Moon virtually stationary in the field at 310X. The declination quadrant slow motion worked well in one direction, poorly in the other, so I'll have to dig into it (checking alignment and electrical connections).
One question...need to complete the collimation...the one I did leaves much room for improvement. What laser collimator would you recommend?
Enough for now...the ibuprofen has kicked in! More to come later...
Posted 22 November 2012 - 04:19 AM
Thanks for the great and entertaining star/moon report from the eyepiece of your Classic Cave Astrola. As telescopes go these are the pinnacle of classic USA workmanship and will always have a place in my heart. I have done quite a bit of observing of the Moon with the 65 10" F8 and it always leaves me in a great frame of mind. The Moon, so close and so far.
Here is a shot of Petavius that was shot with my 1965 Cave. When I was done processing the Video I was, needless to amazed what a ToCam was able to pull from the old Cave.. Keep up the great reports!!
Posted 22 November 2012 - 11:10 AM