ATM Are We There Yet?

[Mark Holm <mdholm@telerama.com>]

> and entered the resulting 4431.7856mm in
> Sixtests as both the Source Distance and the Knife Edge Distance.
> 



You seem to have a moving source tester.  So far as I can tell, it isn't possible

to make a slitless one that isn't.  I believe in Sixtests, you want to enter zero in

the Source Distance for a moving source tester.  The program then changes the zero

into the word "moving".  If the program thinks you have a fixed source tester, when

you really have a moving source, the calculations will be off by a factor of two.


This is a confusing point in Sixtests.  I would suggest in the next version a 
combination of a checkbox for moving source, and the code to turn the text box 
for Source Offset on or off to match the choice of the check box.  This would be 
less error prone in my opinion.

I will reread the help file.  I need to be sure for my own sake since I am using 
sixtests also.  I did feed some of my data into Figure 4.5 and got identical 
results to Sixtests, so I think I am using Sixtests properly

The optimum size of the test mask zones changes with the mirror dimensions.  For 
a 16-inch f/5.46 a six zone mask has zones more nearly the optimum size.  See 
Nils Olaf Carlin's webpage at
http://www.atmsite.org/contrib/Carlin/couder/
  and/or my program CouderMask at http://www.telerama.com/~mdholm/atm/couderma.html

Mark Holm
mdholm@telerama.com