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Messages 19 - 48 of 853   Oldest  |  < Older  |  Newer >  |  Newest
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19
I've almost finished my current project, an 8" F/6.25. I have over a half dozen other ATM projects to choose from. One of them involves making a lighter,...
artbianconi
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Feb 4, 2008
2:34 am
20
I Managed to find a string at Cloudy nights where Mark Harry addressed this problem. The consensus was that it can't be done given the pre-existing optical...
artbianconi
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Feb 5, 2008
8:07 pm
21
... Art, The Schief has a naturally long focal length and high f number. I don't think it will be likely that an off-the-shelf lens to do what you want. You...
Ed Jones
opticsed
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Feb 6, 2008
1:19 am
22
I guess I hadn't posted the 4 inch f/10 CHief (thought I did). Anyway it's posted, check it out. Very simple off-the-shelf design....
Ed Jones
opticsed
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Feb 6, 2008
1:36 am
23
Hi Ed!. I AM rebuilding the Schief! The cradle is overbuilt and thus overweight. It's getting a far better design made from low density structural foam and...
artbianconi
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Feb 6, 2008
3:21 pm
24
Art, No you can't use your comvex secondary, a Yolo needs a concave secondary which you'll have to make and I would need to design. I would really recommend...
Ed Jones
opticsed
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Feb 6, 2008
3:46 pm
25
I am in the process of making more simplified optical layouts for those who aren't familiar with the Zemax data. These are the BMP files. Also note that some...
Ed Jones
opticsed
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Feb 21, 2008
2:30 pm
26
... Thanks Ed! I really enjoy contemplating your designs. I would like to attempt something in the 6"-8" range for planetary observing. What would you ...
sarastror
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Feb 23, 2008
4:56 am
27
... Well I suppose the easiest to make would be the CHiefspiegler since you can buy optics for it. It depends on the f number you want too, they go from >F/20...
Ed Jones
opticsed
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Feb 23, 2008
3:07 pm
28
HI Ed, To step in here, what f/ratio would I need for a 4 inch with no correcting lenses for a Herschelian scope? And is there a mirror source? ...or is all...
Pete Hallock
pfghwest
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Mar 3, 2008
7:33 pm
29
Pete You'll need a radius of about 200 inches radius or f/25. That's a long tube. Ed...
Ed Jones
opticsed
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Mar 3, 2008
8:15 pm
30
Thank you,, Ed .. Maybe a stick OTA first.. Simple is good, because I do not have the ability to have anything more complicated.. To find a mirror with those...
peter hallock
pfghwest
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Mar 3, 2008
8:22 pm
31
Both mirrors on my 6" Schief were ground and polished to 220" radius. The tool for grinding and polishing the Primary became the secondary after being...
artbianconi
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Mar 14, 2008
10:38 pm
32
Thank you, Art. Is a diagram in our files? Have you posted any pictures, anywhere? Terrific posting ,answers some of my questions, too..Have made a 6/f8 and a...
peter hallock
pfghwest
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Mar 16, 2008
12:15 am
33
In the files, the first one, "Kutter Type Schief", what is "Thickness" I believe we understand all else. BTW, where can I find a complete outline, a web site,...
Pete Hallock
pfghwest
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Mar 16, 2008
12:45 am
34
Pete, The thickness is the same as airspacing, negative is right to left, positive left to right. ... I'm not sure what you're looking for but if you Google...
Ed Jones
opticsed
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Mar 19, 2008
1:21 am
35
Hey Ed!! 1) Am I understanding correctly that your Yolo designs do not warp either mirror nor require a toroidal figure? 2) The 6" design looks to me like it...
true_blue_texican
true_blue_te...
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Mar 19, 2008
3:59 am
36
Ed, Thank you, that Will be a big help. I'll Google Kutter..and also see the original Sky article. Pete ... Looking for last minute shopping deals? Find them...
peter hallock
pfghwest
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Mar 19, 2008
5:04 am
37
Hi Chuck! ... Correct, it has no cylinders, toroids or warping. ... You're reading to much into it, there won't be a difference that you can see between the...
Ed Jones
opticsed
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Mar 19, 2008
12:53 pm
38
Hey Ed!! I'll try to keep it below 10 ;-) 1) Where do you get the "optisig" or "optosig" lenses? I googled both spellings but couldn't find a lens company....
true_blue_texican
true_blue_te...
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Mar 19, 2008
7:22 pm
39
Chuck, ... Good, no 60 questions. ... Look in http://www.optosigma.com. They'll cost $63 & $67 coated. ... I made them myself, there's not a big selection...
Ed Jones
opticsed
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Mar 20, 2008
2:15 am
40
... Just wait 'till I start building the beast!! :-)...
true_blue_texican
true_blue_te...
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Mar 20, 2008
9:18 pm
41
I had to replace the primary on my window scope due to an "incident and I got the replacement back from the coater and into use yesterday. I'll have to adjust...
Ed Jones
opticsed
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Mar 22, 2008
1:21 am
42
hi ED i live in pa i was wondering if you have a local club that grinds glass i an not sure it there is any around here i live 1.5 hours east of pittsburg...
airfrederick
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Mar 25, 2008
12:16 pm
43
Kevin, There is only astronomy clubs around here. Myself and one guy in our astronomy club are the only ones making mirrors that I know of. Ed Jones ... hours...
Ed Jones
opticsed
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Mar 25, 2008
9:05 pm
44
Hi Kevin, I'm in Easton and unfortunately don't know of anything west of here. The DVAA is a bit west but I don't think they have any organized ATM activities;...
Gary Fuchs
gfphoto2003
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Mar 25, 2008
10:26 pm
45
thanks GARY i thoight it would be nice to have a club where we could test mirrors and talk about diferent telescopes/. not many people interested in making...
kevin frederick
airfrederick
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Mar 26, 2008
11:52 am
46
hi ED I was reading on cloudynights you were saying that using a coma corrector and a hyperbolic primary you would get a better image . How much better image...
kevin frederick
airfrederick
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Apr 4, 2008
5:11 pm
47
Kevin, A 26 inch is quite a project! Yes a coma corrector will introduce some spherical which can be improved by overcorrecting the primary. One thing to keep...
Ed Jones
opticsed
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Apr 5, 2008
3:01 am
48
Does anyone have a picture of testing the fringes and coring the secondary of a Kutter schief that I could publish? Ed...
Ed Jones
opticsed
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Apr 7, 2008
1:50 pm
Messages 19 - 48 of 853   Oldest  |  < Older  |  Newer >  |  Newest
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