I noticed that there has been no real traffic for a while so here's some eye candy for the planet watchers. http://www.pbase.com/praxis178/astrophotos Enjoy! ...
Hi all, I am a newbie and am in need of information. I have a Celestron C8 Schmitt Cass. and I want to attach my olympus E510 to it. I have been told I need...
Greetings to all on the ATM_FREE Group. I will be moving from the Texas Panhandle back to Lincoln, Illinois sometime in the next 3 weeks or so and during that...
The t-ring is that collar that attaches to the camera just like a lens. Screwed into the t-ring is the nose piece - either 1 1/4' or 2" - which is just the...
Stephen - I had it in my mind that an eyepiece was a part of the setup. Thanks for clearing that up for me. Dan ... lens. Screwed into the t-ring is the nose...
Ken, I can only say: you're welcome, and it's been a pleasure to put something back into the community that has given me so much. Good luck with the move, and...
Dan. It depends what you want to photograph.. If it's the planets or Moon close-ups then you will indeed want eyepiece projection. Dave ... From: "Dan"...
Hello Dave, I don't have a tracking motor on my scope as yet so the moon and planets are my main objective. Which brings me back to my dilemma. What is...
I have always had the itch to do a ATM Cassegrain .. either Dall- Kirkham or Classical Cassegrain. I've done a few Newtonian mirrors so I can handle...
I make 10" and 12.5" F/24 DK cassegrains on a regular basis. It would be by far the easiest cassegrain type to make. As you know the secondary is spherical and...
Imaging without a motor drive and the C8 will limit the exposure time to under well under a second. Fine for the moon but not great for anything but the...
Hi Tony, I was leaning towards a classical Cass for two reasons: 1. it has far better coma performance than a like-f-ratio DK 2. the primary is a paraboloid....
Hi Rob, Since you're looking at a fairly long focal ratio system (F/15-18) I wouldn't think that the extended field performance performance would really be an...
This would strictly be for visual .... lunar/planetary/doubles. With bigger CO and longer tube, I don't think Gregorian is worth it. I won't use it for ...
In that case it really sounds like a longer focus DK would be the best balance between performance and ease of construction. Tony ... From: "albireo13"...
I guess it boils down between which is harder to make successfully .... the ellipsoidal DK primary or the hyperbolopidal CC secondary. If I go DK, what...
Hmmm ... I'd like to play around with a SW simulator to check sensitivity of a design to variations in tilt and separation. I'm not a precision machinest so...
Well, you already know how to make the primary so you may find that easier. For testing a DK primary you'd use the same testing techniques that you're already...
The DK is easier to make both optically and mechanically. For the secondary, you just make the secondary tool into a spherical test plate (foucault null...
I HEAR AND OBEY!!! SOON'S I GET SOME FREE TIME! I have CassDesign Rev 2 (CD2) in work right now, trying to finish up incorporating the 3-ray baffle tube...
Hi Mike, Awesome! Do it when you can. This is a hobby for most of us, after all. Cheers, Rob ... up ... Astronomy ... me. ... programming, ... GUI to ... use ...
Hi again. I've been off telescopes for a while awful weather in the UK and much of the summer is a wash out in anycase. It's getting better but still cold and...
Hello please see the three ronchigrams on: http://tech.groups.yahoo.com/group/atm_free/files/Leandro/ filenames 'rework1.jpg','rework2.jpg' and 'rework3.jpg' ...
Hello Leandro, There may be more experienced eyes that can provide a better interpretation of your images, here are mine: Ronchi is not the best method for...
... If the Ronchi test is made at the radius of curvature so that a single band is placed across the surface, then I find the Ronchi test as good as the...
Yes, it is getting smoother although I think it still has room for improvement there. You have lost a fair amount of correction so you might try alternating...
Hi Leandro. I'll be a bit more positive with your new images. I realise you're not asking us if you are finished. ... Yes I think you have greatly improved the...
Hi Tony, Tom, Mel, Brock, thankyou for all the feedback :-) I'm going to continue this job this weekend, and will make a Couder mask to start measuring the...
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