Re: Film Length vs Dev. Time

OK, confession time.  I went back and looked at my exposure notes and 
found that the subject for the frames I was examining was of high contrast.

However, for a normal contrast landscape, the negative contrast was 
still nearly one grade higher in the 7-frame clip than I usually get 
with a full roll.

The test was 35 mm TMX in Xtol 1+1 in a typical stainless steel tank 
that was about 3/4 full of developer.  There were two reels in the tank, 
and the agitation was 5 inversions every 30 seconds.  I have always done 
very vigorous inversions with Xtol because I read somewhere (probably in 
this ng) that Xtol 'likes' energetic agitation.

Thanks for all the comments and suggestions.  They will be useful as I 
continue this test.  So far, the TMX looks very good in Rodinal 1:100. 
(Agitated two gentle inversions every minute.)  There is a noticeable 
graininess in smooth mid-tones, but the prints have a slight edge in 
sharpness, and the midtone contrast seems a little higher.

Bob

-----------------------------
Richard Knoppow wrote:

> HypoBob <[EMAIL PROTECTED]> wrote in message news:<[EMAIL PROTECTED]>...
>  
>
> > Is there a rule of thumb that relates development time to the amount of 
> > film to be developed?
> >
> > I just did some development tests from 7-frame segments of a 36 exposure 
> > roll.  One test was with the developer I normally use, and to my 
> > surprise the negatives came out nearly 2 grades contrastier than normal. 
> > (Of course I had to put the usual amount of developer in the tank to 
> > cover the reel.)
> >
> > If one of my 7-frame test segments is just right for M minutes with 
> > developer D, it appears that I will have to adjust M when developing 
> > full rolls of 36 exposures in developer D.
> >
> > Bob
> >    
>
>  What kind of developer and what kind of tank are you using?  This
> does seem an excessive amount of change.
>  I do similar tests using short rolls usually processed in a single
> spool 35mm Nikor tank. When a very dilute developer, like Microdol-X
> at 1:3 is used for a full 36 exposure length of film the developing
> time must be increased by perhaps 10%. I don't find any extension when
> using D-76 1:1 my usual developer.
>
> Richard Knoppow
> [EMAIL PROTECTED]
> Los Angeles, CA, USA
>