Re: Fw: [APML] Tak FSQ-106

[lkt <tan@cox.net>]

Monte,

 	I have used the Tak FSQ a few times for 6x7cm astrophotos. This scope
has everything one would want for a 4" astrograph except for the light
drop-off. In many of my shots I do not notice this at all except for the
deepest shots. How deep a shot depends on the amount of light pollution
at your site. The illumination of the Pentax67 frame does not have the
usual obstruction type vignetting. You will not see a dark/black band
around the edge of the negative. The image field is very flat and the
stars exceptionally pin point across the negative. Focusing and framing
is exceptional. By this I mean using a 22x loop to focus on a bright
star has a snap precision to it. You know you are in focus. The rotating
focuser is also very nice for framing. The only negative is the light
drop-off. I believe that many 6x7 astrographs have a light drop-off as
well but this scope appears to be more severe than the average. This is
just my opinion as I have not empirically measured this. Using Photoshop
anti-vignetting techniques is a must for the deepest exposures. 

Loke




--------------------------------------------------------------------------------------------------------
Yes - Both 35 and 120. My comment before relates to wanting to know if
there is gross drop off like a stop or more or is it subtle?
 
 

       ----- Original Message ----- 
       From: Chris1011@aol.com 
       To: astro-photo@seds.org 
       Sent: Friday, May 03, 2002 11:07 AM
       Subject: Re: Fw: [APML] Tak FSQ-106 

       In a message dated 5/2/2002 8:06:03 PM Central Daylight Time,
montezinho@bigpond.com writes:


          To be fair I am still getting through a few teething problems
with my equipment so maybe I haven't given it a fair go yet to date it
          has not been apparent. How much of a difference is there from
the middle to the edge? Is there a value in stops you can indicate?




       Are you shooting 6x7 format?

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