[Aavso-photometry] Which CCD for Photometry? : STL-6303E Vs ST-10XME

[Stewart Yeung]

I am on the verge of ordering an STL-6303E but then
some ideas about the ST-10XME come up in my mind :

1.   The KAF-3200ME is (much ?) more sensitive and hence performs
       (much ?) better behind photometric filters and narrow-band filters.
2.    Dynamic ranges, low dark currents are similar .
3.   Photometry doesn't require a wide FOV (?). Aesthetics does but
       it is not critical : not too many wide celestial objects and one 
could
       always do mosaics.
4.   The ST model can be coupled to a spectrograph and hence a really
       multi-functional tool for expanding scientific repertoir.
5.   The medium format CCD and filters are cheaper.
6.   The ST model comes with a 10-position filter wheel.

But nothing is perfect and compromise is always the norm.

a.   Is the transparent gate/ micro-lens design ok for photometry ?
      ( Some textbooks say that there are no evidence against it.)
b.   Is the shallower well depth (  77,000e Vs 100,000e ) reducing
       the SNR and  linearity range significantly ?
c.   The smaller pixel size (6.8um) makes well-matched image scale
       difficult to attain and necessitates a stonger focal reducer (say 
at 0.67x)
       which will degrade image quality more (coma, curvature,...)
AND
d.   Blind spots (unknown disadvantages which I am totally unawared of)

Any advice from astrophotometrists ?

Regards,
Stewart