speed losing developers and zone system

[gonzalo_echeverria]

hi,

 

didn't even know how to do a search on this one so many

apologies if this one rivals pink negs....

 

if the developer i'm using, which happens to be microdol x,

loses speed ( let's say halving the ei or a loss of a stop) , do you

lose zone II ? does zone II become zone I therefore reducing the

effective range of the film by one stop?

 

another way of asking is this; by losing a stop on the toe of

the curve, do i effectively lose a stop on the shoulder?

 

the film in question is apx100 ( just in case ).

 

 

thanks . gonzalo.

[andrew_hull]

Gonzalo:

 

I may be confused by the question, but if you know that you lose speed (I assume you are developing APX100 in stock Microdol because at 1:3, which I recommend, most films are at rated speed), then you should shoot at the speed at which working strength gives you. If you are then exposing at that speed (i.e. 50 if you are losing a stop of speed), then you shouldn't lose anything. Maybe I am off, but the is what I think that I think ;-)

[bruce watson]

If you follow the Zone System, one of the first things it want's you to do is find your personal exposure index (EI) for the film/developer/process that you use. The reason for this is that there are lots of factors in play in developing film. So many that you have to esentially calibrate your film, your developer, and you yourself. And that's what both the EI tests, and the normal film developement time tests, are all about.

 

Once you have your EI nailed, then you can worry about how to expose your negative - where to place the various zones. Until then, your process is out of control and unpredictable, IMHO.

[jan_brittenson]

Microdol-X at stock, and to some extent 1:1, will have a higher toe. A lower fogging speed. The scale gets a little stretched, so things that were 3/4 tone and down are progressively stretched out. So dark tone contrast is a little more than the contrast at the high end of the scale. This is what causes the chalky look if you have significant image detail at the high end. If most is on the low end OTOH it looks good; like outdoors with bright skies and clouds, the clouds and sky will look more marble than chalky while the rest of the image is in the lower more contrasty part of the scale. A #8 or #12 can help here, without looking overdone. A #25 can work very well, with the usual increased exposure and reduced development.

 

The particulars of the scale can be a problem if you don't expect it. But if you take it into account during composition it can be a great benefit -- you can fit a very long SBR without completely flattening the scale. If you shoot in flat light, place the scale so it stays at the lower 3/4. The negs will be a little thin, but will reproduce in print with a nice snappy look. (They may not scan as well though if that's your use.)

[ken_schroeder]

Gonzalo, try exposing many frames at the indicated exposure and then at twice the exposure. You may prefer the softer, more luminescent shadow detail to the "snappy" prints. If you choose to switch to the "slower" speed, you may have to cut back on development somewhat. (Try 20% for starters.)

This is not new....Dr Paul Wolff, the great Leica apostle, wrote in 1935 "give full exposure and abbreviate the development". I routinely shoot Tri X at 200 with HC 110 B.

[gonzalo_echeverria]

sorry guys - realised that my question was not really developer - based. thanks anyway.

 

the question was about how much sbr a film can hold (varies with film) and if losing a stop on the bottom (toe) meant that effectively you've lost a stop in the film's capacity to render the sbr.

thanks for everyone's input. especially Jan's - i like your images!