Re: [APML] Horsehead and Pleiades testshots with 6x9 camera/OAG and BRC

["tan@home.com" <tan@home.com>]

Bobby,

	I am using a vaccum pump but yes it is still possible that film creep can 
be happening at the edges. Thanks.

Loke


Bobby Middleton wrote:

> From: <tan@home.com>
> 
>>When I look
>>at the diffraction rings on axis, they appear virtually concentric so I
>>think it is almost perfectly colimated, at least I think so.
>>
> 
> I think your diagnosis is correct Loke. The spikes are all identical. This
> means you are right at perfect collimation I believe. You may have had some
> corner film creep on the HH image instead of mis-alignment. My spikes on the
> other hand have one spike that is less focused than the other 3. It happens
> to be the spike that is on the same side as my "fan" of the fan-shaped stars
> I am getting.
> Bobby M
> 
> 
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