[APML] OT: ccd using red filtered 50mm camera lens

[Stuart Heggie <stuart.j.heggie@sympatico.ca>]

Aplogies in advance for the ccd post but wanted to share my very first 
attempts and to close the loop on a series of posts some time ago re 
using camera lenses to autoguide.

My first two attempts to shoot with my ST-7E and my 50 Nikkor lens are 
at this address:

http://www3.sympatico.ca/stuart.j.heggie/Stuart.J.Heggie/CCD_Photos.html

I used a 24mm lens to find the target - amazing to me that this worked - 
centred it - then swapped the 50mm with the red filter. I stopped the 
f1.4 lens down to f5.6 and shot unguided (see comment below) 18 x 5min 
and the G-11 tracks plenty well enough to go 5 min without correction at 
this short f/l. Everthing except levels and curves were done in CCDSoft 
5.0 and the final tweaking of levels and curves were done in PS 3.0

I am going to run out and buy an H-Alpha filter so I can extract more 
signal and less noise but these first results have encouraged me. Thanks 
by the way to John Mirtle who has been coaching me off-list and whose 
suggestion that my old red filter from my B&W film days would help.

I wanted to share the images of course (which I'm quite surprised by for 
my first attempts) but also to report that my G-11 could not be guided 
by a 50mm lens on the ST-7 because it could not record enough movement 
during the calibration step.So, since I asked about that some time ago 
when I was contemplating using camera lenses instead of a guidescope - 
thought I had best share the result.

Comments, criticisms and rebukes all willingly accepted.

Stuart

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