Ok, I'll bite.... For what it's worth. I've not had luck with these calculators matching my observations. I tend to see about 2 magnitudes fainter stars...
Well, the copied formatting from the mag cac site did not transfer like it looked when I pasted it in my email, but, the two conditions are: 20" Telescope,...
Steven, You must be very experienced observer with excellent eyesight at a pristine location. Very few people reach magnitude 20 with a 20" scope. Your numbers...
Hi Robert, I have been at this observing thing for a while. With the things I've seen I'd say, given my vision, scopes, nights of exceptional seeing, that I...
Thanks, if there are adverse effects by altering the exit pupil for having used high power, though the result comes closer to my observations and puts the...
By modifying the html for Bogen's Schaefer-derived to correspond to the correct reflectivity of my telescope's mirrors, and also modifying the pupil diameter...
Don, While I'm well familiar with Schaefer's 1990 paper, the 1998 article in S&T seems to be missing from my collection, and I don't know the details of ...
Don, While I'm well familiar with Schaefer's 1990 paper, the 1998 article in S&T seems to be missing from my collection, and I don't know the details of ...
Sorry about the double messages - the difference was that in the first version, I incorrectly stated that the experience factor was not included in Robert...
Hi Robert, Steven's experience with his 20 matches mine with my 20. When going after some of the very dim targets that I do, I have seen that I can detect...
It's interesting that the visual recovery of Halley was brought up. I too remember reading about that observation and just a few weeks ago I looked up the...
looking again art Schaerfer's article (it must have been over 10 years since last time I perused it), I find these comments, that might be very relevant ...
Nils Olof, ... In the calculator the NELM deals with that, any value larger than 7.0 is interpreted by the Javascript as a perfect sky plus a sensitivity...
Nils, Replies below. Don ... Wasn't that a 1989 article? ... Look at the html code behind this page: http://www.go.ednet.ns.ca/~larry/astro/maglimit.html In IE...
Robert, There is dark adaptation and there is dark adaptation. To wit: in the old days, serious observers doing threshold observations would often cover their...
Hello, This email message is a notification to let you know that a file has been uploaded to the Files area of the bigdob group. File : /Collimation...
bigdob@yahoogroups.com
Jul 4, 2009 2:06 am
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Yes, although it's hardly big enough to qualify for this group: <http://www.stargazing.net/wvas/BigBinocs/Binocular.htm> -John...
Don, ... In the new calculator you can enter your true pupil diameter instead of relying on the automatically calculated age-dependent value. Other changes...
... Seems many observers are not aware of this, but you will notice that after looking at a dark branch against the dark sky, moving your gaze shows there is a...
Don, ... You're right - I copied the wrong year from somewhere I can't recall now. ... While this is possible, I just don't think it's fair to the user to...
Don, thanks a lot for this - it helps to have something substantial to discuss. ... It would be nice to choose from standard valuer or calulate the recipe for ...
Nils, I think that an experienced observer will always see more through a scope than an inexperienced observer--in all conditions. So experience is important. ...
While enjoying the discussion, I had to comment... Glad to see reference to this classic cartoon by Sidney Harris. I first saw it a few decades ago in American...
New to the group and while my 10" dob would hardly qualify as big, I regularly attend new moon weekends in Chiefland, FL where there are very dark skies and...
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