Re: [APML] SBIG STV-eFinder??????

[steve banbury <banburys@sonic.net>]

I have no difficulty focussing the STV with my Nikon 135 mm f2.8 telephoto
using diffraction spikes as indicators of critical focus.
This technique seems to work better for me than a Hartmann mask.
At $40 for a used Nikon lens and $70 for a CLA-5 lens adapter, it was more
bang for the buck(s) than SBIG's $245 f3.75 FR237.

Seagull-shaped stars in cheap lenses, or near the edge of the focal reducer
lens in a Lumicon GEG do adversely impact the STV performance.

Steve

At 12:59 PM 6/18/02 -0400, Kent Kirkley wrote:
>A question for STV-efinder users??
>
>In the last year there was some discussion of the SBIG STV and efinder.
>Some individuals felt the efinder was difficult to adjust in achieving 
>critical focus.
>Some individuals were using short telephoto lenses (200mm and under) with
the 
>STV instead of the efinder.
>
>Now that some time has passed and more STV's and efinder's or telephoto 
>lenses are in use, what is the current appraisel of the STV and efinder???
>



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