The consequence of using NEWT is vignetting by an undersized diagonal. The degree of vignetting renders the scope useless for variable star brightness...
unsubscrive atm ... The above is correct only for very high power long focus telescopes, not for low power wide field instruments, and not for telescopes used...
I have a program that will computer the light lost in your telescope from vignetting at the tube rim, the central obstruction of the diagonal, vignetting at...
Hi all, was just wondering what the other advantages and disadvatages are of larger of smaller focal ratios (as compared to mirror size, or without any...
I assumed the telescope was for general visual observing. But you are right of course: for astrophotography and situations (mentioned by you) where one needs a...
Dear all I have polished out my 150mm f/6.2 mirror according to al known tests to me (incl. sun and laser). I now want to figure after many delays and ...
Dear all I have polished out my 150mm f/6.2 mirror according to al known tests to me (incl. sun and laser). I now want to figure after many delays and...
Hi Group Honestly, I did not expect to receive such large response from all of you. I am overwhelmed and this is going to keep me occupied for a lot more time...
Good drawing. You have a sphere with a bump in the middle. Just consider it a sphere. The bump will go away quick when you start parabolizing. Do 2 or 3...
Be sure to ingore all of the replies (except mine, of course!). They don't know anything. Only I am right. . . . Richard ... From: Prasad Agrahar To:...
Sorry these are really basic questions, but I need to get the information. About pitch: Summer temps here average in the upper 80's to lower 90's. I will be ...
Wish that I could tell you exactly what pitch that you want to use for the temp range of your basement but that often ends up being related to how you handle...
Thanks. I was afraid it wasn't that simple. <g> Ok, if I err, which I probably will, to which side would I rather err? Too hard or too soft? I've heard...
3877
Krajci, Thomas J
KrajciTJ@...
Jun 3, 2004 4:27 am
... And you're right, it's not an accurate test. And Bob May's answer, in my opinion, didn't help much. Go to: http://astro.umsystem.edu/atm/search.html and...
3878
Krajci, Thomas J
KrajciTJ@...
Jun 3, 2004 5:25 am
I'm helping out a newbie to astronomy that has a small telescope. However my bookshelf has books with more advanced topics. What books for a newbie would you...
I'd recommend "Star Ware" by Phil Harrington. Gives the low-down on selecting, using and caring for a scope. Ideal first book for the new user. As well, he...
Peercy, I am not Richard, so my advise is wrong (S) Let's assume you just bite the bullet and go for a softer pitch. If you boil it some more, it will lose...
Yep, you are not Richard, and your advice is wrong. Everybody is worng but me! Yes, you can soften pitch with turpentine, but after a while the turpentine ...
Greetings All, What a very exciting evening I just experienced. Tonight was the first cut for my newly constructed "Robo Glass Mill" I still have a bunch of...
Just out of curiosity, did you check my web page on how to cut out glass circles and edge them? ... cut for ... do, ... used for ... Including the ... (on the ...
James: I have lots of surplus Pyrex elliptical blanks up to 6" minor axis diameter. Could save you some work ;-) I also have large aperture blanks if you need ...
... diameter. James... If you don't get any offers from James Lerch on the large diagonal blanks, I'd be interested in picking up a couple to play around with....
Hi all! Just returned from the RTMC. Lotsa fun.... My latest problem... I just got a piece of Sonotube. There is a layer of goo (wax?) coating the inside wall....
... Last time I tried (mid 1970's), I just peeled the inner layer of paper away, then painted what was left (it was nice and fuzzy). Maybe Sonotube has changed...
Tom, I test painted three areas of a Quick-Tube sono tube. One area I removed the "wax" with lacquer thinner. Another area I pealed the paper, The last area I...
An early experiment of mine related to generation of elliptic blanks. I filled a crucible half way up with tin, and floated the glass on top. The idea was...
