Hey folks, It kills me to see Ken Hunter struggling and having to sell off his hard fought ATM Gems just to cover medical bills. Is anyone on this list...
... Cary, ATM_FREE Group Members... While I thank you for the nice offer and sentiment, I DO NOT NEED ANYONE TO DONATE FUNDS MY WAY... I have many things that...
Hello... Can anyone tell me what the 75% "cone" or "field" is? I'm not sure I'm grasping it. I require detailed explainations in order to understand things. ...
... sure I'm ... understand ... Hi Jimbo and welcome to ATM_FREE... Imagine that you are looking at a star that is directly on the telescope's axis. The front...
Thanks, Ken... That explaination got me most of the way there. The only aspect I don't understand is whether the 75% axis is parallel to the optical axis, or...
... optical ... For each point or star that is off axis, there is a point that corresponds to it at the focal plane. As the incoming point moves from the axis,...
Hello. . . I am doing simulation of optical system ( both on axis and off axis)in OSLO software,and i use FFT based PSF to see how the spot of system will...
I believe it enters at an angle, now that I think it through. The reason is that any directly parallel ray WILL wind up at the focal "point". The angled rays...
I see... Then the program "Newt" is incorrect in representing the 75% cone at an angle to the optical axis. Are you familiar with that program? Jimbo...
...no...that's incorrect, as well. The point will eventually "diverge". I'm not getting this. I have some kind of mental block. Jimbo ... I ... these ... ...
... Jimbo... The light bundle coming from a star ON AXIS will be reflected from the primary mirror back along that axis and will form a point image at the...
The very concept of the 75% field is going to prevent a telescope from doing variable star photometry. Variable star observers work to 0.1 magnitude. That...
...so, off-axis means at an angle? Because all of the trig I'm doing tells me that any parallel ray will hit the center of the focal plane, by virtue of the...
... Yes... Although the light bundles coming into the telescope is all parallel light from each source, it originates from different places. Each point off...
Richard, Although I'd love a copy of your program, I don't have a palm, too bad. I do have two questions, though... 1. Doesn't there have to be SOME...
Richard, Although I'd love a copy of your program, I don't have a palm, too bad. I do have two questions, though... 1. Doesn't there have to be SOME...
Jimbo, ... Yes. Stars, for example, are so far away that light that reaches from us is practically parallel. If you are looking at two close stars in the...
Richard, because you don't understand something isn't a reason to throw it out. Newt produces both a 100% and a 75% diameter value for the incoming light. For...
The 75% sone is the diameter of the focal plane at which the light falloff is at that point. It is indeed referenced to an angle (has to be as it is off from...
Read the discussion at http://www.megspace.com/science/sfe/i_en_dia.html. There is a link at the bottom of that page you can click for the actual program. ... ...
I truely am sorry to have caused such controversy...I thought it was a simple question, which shows just how "simple" I am...eh? In the grand scheme, it really...
Gals and Guys... I'm sorry to do this to you, but I'm leaving this group - the response time is just too long for my expectations. I guess that's the tradeoff...
...then the concept of parallel rays is not entirely true...because, eve a star from a great distance away (pinpoint) will not project parallel rays to the...
I still don't know what you mean by move the light bundle off-axis. Therein lies the problem, because there is more than one way to move the light bundle...
Hey...I just thought of something...why doesn't Yahoo take all of that advertising profit from the banners they wave in our faces daily and invest it in...
I can understand your reluctance to stay with this group... after all, you joined yesterday and I approved all of your messages as soon as I saw them and spent...
What does off-axis mean? Is it off-parallel or off-angle? There needs to be more thourough description. Jimbo ... falloff ... it is ... to ... is that...
?? ... http://www.megspace.com/science/sfe/i_en_dia.html. ... actual ... express for ... high ... But if ... anything ... photography, ... vignetting ... edge...
... "On axis" refers to the image point being on the axis. The light initially is coming straight down the pike, no matter where it hits the mirror -- like...
Sounds like Jimbo is one of the type that demands instant response to his questions. He seems to forget that we're not here to answer his questions that he...
