Re: [APML] Rho & M8M20

["Steve Lindsey" <stevelindsey@earthlink.net>]

Thank Stuart.  That's interesting you could go that long at your site.  In
that case the grain may be from the pushing on the Rho shot.  I don't see
any grain on the M8/M20 and had virtually no vignetting so I don't know what
to say about the comment that exposure time doesn't solve vignetting.  It
sure de-emphasized whatever vignetting was there but I'm sure limited me to
bright objects as well.

Thanks again and good luck with the 180mm ED!  That lens is on my wish
list!!

Steve


> Steve, on the Rho picture you say 45 min at f4.5. From my site 45 min on
> 400 film at f4.5 is the sky fog limit so I think your exposure choice is
> correct. I have not been to the RTMC but would assume it is relatively
> dark as is my location. Pushing two stops would explain a lot of the
> graininess you mentioned but that would seem excessive given the exposure.
>
> On the M8M20 shot, you give the same data but exposure 15 minutes.
> Pushing that two stops would be about the same as 45 min unpushed AND
> explain the grain. Assuming same roll of film, I'm guessing the 45 min
> exposure was pretty wild looking prior to processing in PS.
>
> Also, I don't think the experts recommend backing off exposure duration
> to solve vignetting, you remove what you have as you did using an AV mask.
>
> Great shots in any case - I'm warming up my 180mm ED lens in anticipation!
>
> Stuart


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