Hi all, Im new to ATMing and just got a 6" f/15 jaegers for dirt cheap. Its not going to be my main observing scope or anything, just a planetary killer and a...
Richard Berry has a nice refractor tripod in one of his books on building several telescopes. I'd also suggest that you look at Hastings Irrigation (they're ...
... Jeremy, Congrats on getting the Jaegers 6-inch. Can you tell me how to get one, too, just as quickly as you did? In all seriousness... . :-| For a design...
Greetings all, What is the required minimum diameter of a Plano-convex lens in order to test a 10" f/5 parabolic miror with Ross null test? Can I use a 3" ...
Hi, you can see the details @ http://www.optics-online.com/pxp.asp (Plano-convex lens, precision grade / 75 mm diameter) It is curved (R=95.963 mm) ... order ...
... Personally, I cannot get to that site; it stalls on me. However, given that you already know the shape of the lens, then, for each wavelength, there is...
... You need to play with the software first to get a feel for the errors. But the focal lenght is more important than the diameter.Bigger is better cause you...
Joe, Thanks for the help. I actually got this from my club's old equipment for sale. It used to be piggybacked on a 16" classical cassegrain in an observatory....
Im getting a copy of those pages to build the 6" f/15 in that book and i've contacted hastings about this. What does it take to make a crayford? I wouldnt mind...
... Hi, Jeremy, I think that, even in a less than world-class dark-sky site (like, a city), the performance of a planetary 'scope will be helped out by ...
... Jeremy, Anodizing is usually done by local industrial coating businesses. Very handy! You can drop off, and pick up. No shipping charge! There's even one...
... Jeremy, If "clear" anodizing is all you need, you can do it yourself! Granted, the amount of buildup, and hence the amount of protection you can get this...
Baffleing is absolutely necessary for your refractor and blackening will be an additional help. You can refer to the ATM series of books or to any good text...
... wrote: Hiya, Jarvis, I must say that baffling is not a necessity, and especially not an "absolute" one. I had the privilege of using an Alvan Clark 12...
I've done several differeent designs of Craygords. One was a flat end cap for the tube of 3/8" thick aluminum plate with the central hole for the tube to go...
Jarvis, et al., I must say, I am mistaken. NEWT is *not* a good choice for designing baffles for refractors! It will simply not give a satisfactory result,...
Any advice on how to insure ones telescope after building it...should anything befall it? My insurance agent hasn't the slightest idea on how to appraise my...
Hello Joe, I've just returned from the Table Mountain Star Party and received your e-mail. I know that Clark produced some really excellent refractors and...
So then if baffles are better what makes a good baffle? What makes a poor one? Where is the line drawn for diminishing returns - where adding more flocking or...
Robert, ... Unless I misunderstand you, this sounds like a test at COC. To make a null test using just a flat, you must have the source at infinity focus and...
Steve, Ok I did not realize the key was the source at infinity. I was thinking about how you can use a ronchi screen in a newtonian telescope. So if I want to...
... The very best baffles are circular aperatures that exhibit a knife edge opening concentric with the optical axis and are spaced so that any light that gets...
Dear all, Lurie-Houghton telescope use convex & concave lenses combination to correct sphere mirror, it do perform a good image (diffract limit) compares with ...
Ukyo Chen
ukyochen888@...
Aug 10, 2005 8:26 am
6989
[cross-posts deleted] ... Also it has a sealed tube, an advantage for controlling air currents, thermals, and general cleanliness. ... Some guesses: (1a) the...
