[Aavso-photometry] Which Photometry Filters to Begin With ?

[Jeff Hopkins]

Hello Robin,

An interesting idea. The main problem as I see it is with there  is a 
very good chance of getting the positions mixed and taking data with 
more than one filter in the optical path and not realizing it. If the 
filter wheels are motorized and software controlled this probably 
would not happen, but if done manually I can pretty much guarantee it 
will happen. Late night work in the dark trying to do multiple things 
by yourself is a sure recipe for getting things mixed. Also, a down 
side of CCD photometry is you are less likely to notice the problem 
until the session is over and the data analyzed. With my single 
channel photon counter I have sometime let my mind drift and changed 
the filter in the wrong direction, but the counts usually immediately 
indicate something is wrong. For manual operation, simple is better.

Jeff

At 10:56 -0700 04/16/2008, Robin Leadbeater wrote:
>Stewart Yeung wrote:
>>>  What other options, e.g. different filter wheel, are available ?
>
>Hi Stewart,
>
>Provided you have enough back focus, how about stacking two filter wheels,
>each with one empty position? This would give you 14 options.
>
>Robin

-- 
Jeff Hopkins
HPO SOFT
Counting Photons
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