10246 replies to this topic

[Roger Belveal]

Well... I semi-finished my second Comet Catcher. Here's a picture of the twins and little blue!

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[Roger Belveal]

Excellent info! I was just at Ace this morning (for a different project) but didn't read this until now. I'll give that a go here soon.

 

Yeah, you don't see these C.C's come up for sale often, so you are right to hang onto it. Both of mine were definitely project scopes, so they didn't cost me much..... just a bit of time and effort to get them whipped into shape with some bodywork / paint / etc.

 

Cheers,

Temp

Temp, I've been trying to figure out the best eyepieces for these little scopes and I purchased an 18mm UFF 65° from SvBony.  Not exactly thrilled with its performance. However... I found that my Burgess/TMB 9MM Thru 4MM are tack sharp across 90% of the field  of view! The SvBony 18mm works superbly in my One Sky so I guess it's not a total loss...

[Roger Belveal]

nice dew shield, is it slide on or what?

 

what kind of clean mags can you get out of this? 

 

mine is tac sharp with a 4.8 nagler and shorty barlow on the helical focuser

The dew shield just slips on and is a nice snugg fit. I found out tonight that my Burgess/TMB Planetaries seem to be made for this scope. 9mm down to 4mm are very sharp.

[luxo II]

Made a pair of these to play with. Someone suggested the focus obtained from a Bhatinov mask isn't quite the same as what an EAF and software reach, using the minimum FWHM of stars, and I'm curious to see if this helps with collimation, as well as test the focusing idea... 

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Edited by luxo II, 24 July 2024 - 04:50 AM.

[Michael Covington]

I am wondering how the focus obtained by those two methods could be different, unless simply because of inaccuracy.

[Werckmeister]

The focuser on my 1956 Jupiter (Pentax) 60 mm scope was a bit wobbly and as there are a lot of screws on it, I took it off the tube to see what is going on.
Turns out there are 3 sleds to hold the focuser tube centered, each with two adjustment screws.

So it seems the focucer can be collimated. Never seen that before, nice!! I think I 'll have a go at it later this evening. 

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[deSitter]

I am wondering how the focus obtained by those two methods could be different, unless simply because of inaccuracy.

Having a radially symmetric pattern defeats the purpose. You might as well use the Airy disk instead of dealing with a blizzard of diffraction effects.

 

-drl

[m0bius]

Finally added a tablet mount to my venerable DM6. A marriage of modern and classic I think.

It's very usable and sturdy so far, at least under living room test conditions. (cruddy EP is my dust cap)

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Edited by m0bius, 24 July 2024 - 03:25 PM.

[CHASLX200]

Never saw a mount like that back in the day or even today.

[m0bius]

That there is a Losmandy standard tripod from a GM8 with a tall Losmandy column and a DiscMounts DM6 on top.

Weighs a little less than my mother in law, but perhaps more fun to move.

[andylsun]

First light on the Takahashi EM-2 Nexstar 4 GT combo. Crazy long 1500mm FL from the plate solved images.

 

got 2 hours of the ring nebula. Great RA guiding but couldn’t guide in DEC so no valid logs or RMS values. I think my DEC steps/degree are slightly out. This caused the meridian flip to fail as it was pointing wrong and couldn’t sync the mount so I shut it all down.

 

Super pleased with the RA guiding from a rebuilt mount.

Edited by andylsun, 26 July 2024 - 06:23 AM.

[CHASLX200]

Made the wood pieces on both ends for the saddle of the AP800 to mount the 826 without the dumb D plate.

[KI5CAW]

Put my Thrift Store Telescope (10" f/4.5 Meade bought for $99 at Goodwill), mounted on a DIY Dob mount, up on a short pier, so that the eyepiece is at a comfortable height when I'm standing.

[jragsdale]

So nice having a 3D printer now to zip off any random custom sized parts you need. For a few minutes and a few pennies in filament you can make any size/color dust plug, dust caps, etc. Made dust covers for a 20mm Unitron finder and Jaegers 3" f/5 and a 1.25" dust plug. So quick and easy!

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[jragsdale]

Couldn't find a suitable replacement polar scope cap for the Vixen Super Polaris so I decided to design and print one myself. Got a little OCD with the details so it was as close to original as possible with a touch more tension when inserted so it wouldn't wiggle off once cold. Turned out quite nicely! This was my "prototype" since I had so much white filament. Does anyone know what other scopes these caps may fit? GP?

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[Garyth64]

I believe they will also fit the older CG-5 mounts, as they are practically the same as the Polaris.

But the CG-5's have a little opening to read the RA.

[norvegicus]

Yeah I think the SP and GP dimensions are the same.  I made one for my GP with TPU for a slight stretch fit.  Not as nice or as original looking as yours.

 

Edited by norvegicus, 28 July 2024 - 06:33 PM.

[Garyth64]

Here's the cap for the CG-5:

 

[clamchip]

A friend gave me a foil spaced Jaegers 80mm f/15 lens, he has two, he is keeping the other one with a ring spacer.

I bench tested it today and I nearly had a coronary, it is awful! that is until I flipped the lens the other way and there

that's better, jail bars! the glass is backwards in the cell. I like seeing those jail bars.

Bench testing also tells me the focal length of the lens, 47 inches f/15. Now I just need 4 feet of 3.40" OD tube and

I've got myself a refractor, providing I have a focuser around here and I think I do.

Where am I going to find 3.40" OD tube. It's in the Jaegers catalog!

 

Robert

[deSitter]

A friend gave me a foil spaced Jaegers 80mm f/15 lens, he has two, he is keeping the other one with a ring spacer.

I bench tested it today and I nearly had a coronary, it is awful! that is until I flipped the lens the other way and there

that's better, jail bars! the glass is backwards in the cell. I like seeing those jail bars.

Bench testing also tells me the focal length of the lens, 47 inches f/15. Now I just need 4 feet of 3.40" OD tube and

I've got myself a refractor, providing I have a focuser around here and I think I do.

Where am I going to find 3.40" OD tube. It's in the Jaegers catalog!

 

Robert

Hot tub time machine. That will work.

 

-drl

[clamchip]

Yes that will work.

I need to go back to 1969, Jaegers has a 4 foot length for $6.75 postpaid. 

 

Robert

[cavedweller]

A friend gave me a foil spaced Jaegers 80mm f/15 lens, he has two, he is keeping the other one with a ring spacer.

I bench tested it today and I nearly had a coronary, it is awful! that is until I flipped the lens the other way and there

that's better, jail bars! the glass is backwards in the cell. I like seeing those jail bars.

Bench testing also tells me the focal length of the lens, 47 inches f/15. Now I just need 4 feet of 3.40" OD tube and

I've got myself a refractor, providing I have a focuser around here and I think I do.

Where am I going to find 3.40" OD tube. It's in the Jaegers catalog!

 

Robert

 

How big is the clamchip, clamchip?

[clamchip]

No clamchips this time but it does look like it was cleaned with a fish scaler.

The scratches are in the coatings and can only be seen if you get it just right with a strong light. 

I'm going ahead with a optical tube to see what I've got.

Robert

 

Edited by clamchip, 30 July 2024 - 10:02 AM.

[clamchip]

I mounted up the Jaegers 80mm on a tube and hit my usual daytime resolution test targets.

Immediately apparent it's sharp and high contrast and put a smile on my face easily resolving the perforated

thingy on the cell tower 2.5 mi from my house. 

I looked closer at the scratches on R1 and I don't think it was done by a fish scaling tool after all, it was probably 

caused by a vacuum cleaner nozzle, I'm sure of it. Too bad but you can't see it unless you can strike a reflection

off the surface just right, its only the coatings and almost like a dull pencil lead swirl rather than scratches.

The lens is breathtakingly sharp, easy to read signs across the valley at 150X, 50X per inch. I could have gone

to higher power but the view started running out of light. Heavy cloud cover today making things dark but conditions

were perfect for high power. 

Since my Jaegers 6 inch Mak was handy I switched scopes and went after the same targets same powers. Definitely

a lesson in physics showing what a difference aperture makes. Interesting though, at lower powers the 80mm

is a hair sharper than my Mak. As the power went up the Mak said see ya later alligator to the 80mm, completely

understandable.

 

Robert

Edited by clamchip, 30 July 2024 - 03:50 PM.

[deSitter]

I mounted up the Jaegers 80mm on a tube and hit my usual daytime resolution test targets.

Immediately apparent it's sharp and high contrast and put a smile on my face easily resolving the perforated

thingy on the cell tower 2.5 mi from my house. 

I looked closer at the scratches on R1 and I don't think it was done by a fish scaling tool after all, it was probably 

caused by a vacuum cleaner nozzle, I'm sure of it. Too bad but you can't see it unless you can strike a reflection

off the surface just right, its only the coatings and almost like a dull pencil lead swirl rather than scratches.

The lens is breathtakingly sharp, easy to read signs across the valley at 150X, 50X per inch. I could have gone

to higher power but the view started running out of light. Heavy cloud cover today making things dark but conditions

were perfect for high power. 

Since my Jaegers 6 inch Mak was handy I switched scopes and went after the same targets same powers. Definitely

a lesson in physics showing what a difference aperture makes. Interesting though, at lower powers the 80mm

is a hair sharper than my Mak. As the power went up the Mak said see ya later alligator to the 80mm, completely

understandable.

 

Robert

Yes - you're seeing the scattering from the aluminum coatings when the light is concentrated at low power. They just look different from smooth refractors and it's not a matter of optical quality.

 

-drl