Telescopes

Didn't work out at all, but wanted to share a conversion of a dobsonian telescope into a horseshoe mount that I built a while back. Was a completely failed experiment, but it was also kinda fun.

Old sketch, but just wanted to add some content to this community.

Equipment:

Celestron 8SE

0.63x Focal Reducer

18mm Meade 5000 UWA

1.15° FOV per circle

71x magnification

2.9mm exit pupil

mechanical #2 pencil

white printer paper

The whole chain is too large for the FOV of my telescope so I had to make a “panorama” of three separate FOVs.

Sky Conditions:

Bortle 5/6

“Average” transparency and “Good” seeing according to iCSC

Moon: 75%, rises ~1:00am

Editing: A first draft is made while at the telescope, then I trace it on to a fresh form, make any necessary corrections, then scan it and invert the image in the Snapseed mobile app.

I was originally planning on sketching M104 (the Sombrero Galaxy) assuming that the view would be good, and then M3 if there was time. I had never observed the Sombrero before and I may have just barely been able to see the dust lane with averted vision. This was pretty exciting, but before I dove into sketching M104, I wanted to check out Markarian’s Chain. I had tried this target once before but was only able to make out M84 and M86. But that night I was in for a treat. M84 and M86 were very apparent and as I panned over, the other galaxies came into view. I was beyond thrilled, and the longer I looked the more I was able to see. All in all, I was able to resolve 7 (maybe 8) of the galaxies within the chain:

M84 - the brightest of the 7, just a circular fuzz with a bright/defined core, visible with direct vision

M86 - larger than M84, oval shape and orientation apparent, core is bright but a bit more diffuse than that of M84, visible with direct vision

NGC 4438 - no defined core, more diffuse, fairly dim but not bad with averted vision, oval size and orientation is hard to see but becomes apparent with longer observation, ~half the size of M86

NGC 4435 - averted vision needed to resolve the bright(ish) and well defined core, no oval shape apparent, just a circular fuzz

NGC 4461 - faintest of the 7, no defined core, just diffuse fuzz, just barely visible with averted vision, oval size and orientation not seen

NGC 4473 - bright(ish) and well defined core just barely visible with direct vision, oval size and orientation just barely visible with averted vision

NGC 4477 - just a dim diffuse circular smudge, no defined core/slightly defined, fairly dim but not bad with averted vision

I was maybe able to see NGC 4458 as well. While sketching NGC 4461 and using SkySafari as a guide, I was trying to locate what I thought was a faint star in that area to use as a reference point. I remember thinking that I may have seen a faint patch of light in there. But since I thought I was looking for a star, I just moved on and didn’t think twice about it. Looking back, I think I would have been able to confirm this galaxy if I had known it was there.

Hi, Lemmians,

I wanted to share my experience messing with an old Dobsonian-style scope. My parents had a Coulter Odyssey 10.1" covered by a trash bag since somewhere around the early 90s. We used to have pretty dark nights back then, but the light pollution crept up over the years, and it probably went a couple of decades without any use, so they sent it with me after a visit.

It didn't take long before I was shopping for eyepieces and realizing the original focuser was a sore spot, as it was only a locking sliding tube--no knobs or gears for smooth, precise adjustment. I started thinking about what else I would change and, with their blessing, I decided to have a little fun changing it up.

Not all my changes were improvements, but it was rewarding to tear into it and put it back together with some of my own taste applied.

Full album: https://imgur.com/a/I9Mj1kT

!before !after