Those SS long Jaegers lenses

Finally got some good skies and a little time. 103mm F15 Jaegers is a really good scope. Better than the Vixen A102Mwt I had for a while. Jupiter had good contrast and detail, GRS was visible this evening. M35 was really nice, pinpoint star images across the field. NGC2158 was visible as a smudge.
Eskimo nebula showed some detail and had good surface brightness even at 175x
I live in a full up orange to red zone

Action shot

back inside

Here is my 82mm F15 "test bed". Cell is complete, tube needs to be about 2cm shorter. I'd like to get a better focuser than the $30 classifieds special.

Cell close up... Note; no tube blackening at all yet and the blue painter's tape keeping things from falling apart.

More blue tape. Tasty 28mm RGO in the Tak diagonal(got it really cheap)

I cannot tell to you many times I would have a test rig taped together. I normally use the aluminum tape that is used on heating ducts. That tape really hold things together well.

Nice job Marc. I bought the same lenses. My 83 is going in a Unitron 140 tube with a Unitron focuser and dew shield. The working aperture of the lens is going Down to 76mm to accommodate tube and dew shield. The cell is being machined from a block of aluminum next week. Made Orion 90mm tube rings fit the tube with felt padding from Lowes (very dense and adhesive backed). Another tube ring is refitted to hold the finder. Pictures soon.
I'm waiting for summer to build the 4 inch.

Thanks, At some point soon. I'll finish the 83mm. Like the 103mm Jaegers a lot. Some of my other scopes are not going to get used much.

Kind of funny I designed my lens cells like the Unitrons not having seen one. My 4" cell has a spring loaded retainer made from grey PVC with a 0.125 6061 pressure plate. Looked at pics of some Unitron cells and was like hey! Never liked threaded rings for retainers. Way too easy to get uneven pressure on the lens.

Thinking about a 3" refractor shootout in the backyard tonight. Weather and three year old permitting. He likes the Sears 6339A. "I like this one too daddy" he said last night as he snuck into my room of requirement.

83mm Jaegers F15
76mm Royal Astro F15.8
80mm Vixen F11

Still have a Vintage Towa 80mm F11 lens without a tube.

I still have a few of these 4" F15 lenses I still need to put in an OTA. Lucky for me I now have some tubes long enough to put one in. I did do some early checks on them with an artificial star just to see if it was going to be worthwhile and I did look like they had a very nice figure. I have heard that that the Unitron F15 and Brandons were better. I can compare to the Unitron once I have one in an OTA.

I'll be real interested in seeing how it stacks up against the 4 inch Unitron. I bet it will do well.

Terra

I think Brian might have already done some testing and stated that his 4" Brandon did better than both the Unitron and Jeagers.

Looks good Marc. Amazing, the 83mm Jaegers refractor I'm working on looks almost like yours. I'm not painting the OTA, leaving it a nice shinny aluminum with a few coats of clearcoat on it. And I'm also using a cheap Synta R&P focuser. Only difference is the lens cell. For the moment I'm modifying a 80mm cell that has no collimation adjustments.

Later I may have Crawford machine up a custom one for me.

I'll get some pics for the group once I'm finished. And BTW, I'm using duct tape to shim the cell to the tube.

I did some work on mine at lunch. Shortened the tube 1.00" on a lathe. It really doesn't need a collimatable cell if the end of the tube is really square. My 4" has collimation screws but it's just bolted flat to the tube flange. Everything is very square. I used the rolled paper method to square the tube. An adjustable cell is nice, but not a must if the tube and cell are well machined and square.

Did a little shoot out last night with the 82mm f15 Jaegers.
Contenders:
82 mm F15 Jaegers
76 mm F15.8 Sears 6339
80 mm F11 Vixen A80Mwt Japanese made

Tried to use nearly the same magnification and eyepiece type.

First up is Jupiter. All showed a similar amount of detail but the Jaegers had the best color correction and a little better detail than the 6449 and Vixen. There was a bit more scattered light in the Jaegers, but that is due to the fact that th inside the the tube is bare Aluminum. The Vixen had the brightest image but the extra color was noticeable.
Jaegers wins by a narrow margin followed by the Vixen and the 6339 in a tie.

On the star test. Jaegers was nearly perfect along with the 6339 and Vixen just just behind.
Jaegers by a hair.

Orion Nebula. Vixen had a darker background than the other two, but the trapezium really popped in the Jaegers. The Sears had a little darker image and was let down by a narrower field.
Vixen wins here, I'll try this again when the Jaegers tube is darkened and baffled.

Castor and Delta Gem. I like Delta Gem it's about 5.7" sep and the companion is mag 8.1. All three scopes showed the companion pretty well. the Jaegers looked a tiny bit better than the other two scopes. Castor looked very good in all three.
I'll call this one slight edge to the Jaegers.

Eskimo Nebula. Vixen had a darker sky background than the others. 6449 image was a little bit dimmer than the Jaegers and Vixen
Vixen by a nose.

Conclusions: 6339 is let down by the really long narrow draw tube making wider fields impossible. The Sears color correction was not as good as the Jaegers and the lens is smaller by 6mm. Still a VERY good scope, just a little behind the others.

Vixen has very good coatings and dark sky background. At F11 it has more color than the Jaegers and a little more than the Sears. Nicely made scope and more portable than the other two.

Jaegers had the best images of the three with the best color correction and contrast by a small margin. I need to baffle and flock the tube, the shiny bare aluminum was hurting the sky back ground. My overall favorite of the group. This may be a very good sample, but both my 102mm Jaegers are very good.

Hopefully my Jaegertron will be finished next week (same lens as your 83mm stopped down to 76mm) and I can test it against my Sears #6344 and my Unitron #140, weather permitting.

My Jaegers 83mm project has been put on hold for the time being. After finally figuring out I had installed the optics backwards...flint element is on the outside, crown on the inside, opposite from what I'm familiar with...I now find my objective set has the most horrible CA I've seen through a scope. Worse than my homemade 6" f/5 750mm refractor. Even with a stacked minus violet filter and #8 yellow the CA is bad.

I put my Towa 80mm f/15 objective back in the scope last night and the wonderful f/15 views returned. Tight stars, little or no CA on anything, including Jupiter. The trapezium looked great with a hint of the E star popping in and out. M81 and M82 were easy targets. Who says you can't see deep sky with a small, long focal length scope!

Guys in the ATM forum think I got a bum optics set from Surplus Shed and I should send it back. Any ideas here on how I could fix my CA problem?

Thanks

That's what I said over there. I'm the one that got one that was pretty bad with a FL that was 2.4 inches too long with bad CA and SA.

Looks like another nice night for viewing!! I think the Jaegers 4" will compete with my 6" F8 this evening.
This will be a good one.

Oh, now I can't wait to finish my little 83mm Jaegers too
I have the tube and focuser, just to lazy to go to my machinist friend to make some adapters on lathe

Here is my 6" F8 on the NOT a spindly little Vixen GP mount.
Tube is massive unfortunately. 8" dia with 1/8 wall. Mirror is from about 76 and refigured by Telescopics. It's good but not as good as memory serves. I'll see tonight.

Here is the focuser, smoothest I've ever used. Feathertouch smeathertouch.. Made this one way back from a microscope focuser. Machined the base plate and focus tube