What is a compensating developer?

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I have been experimenting with film and developers. The Film Developing Cookbook has been my guide. The term compensating developer is mention but not well explained. Can anyone shine some light on this subject?

-- Richard Jepsen (richard.jepsen@tinker.af.mil), July 09, 1999

Answers

A compensating developer is one which compresses highlight density range. Or iow, rather than a straight-line response of increasing density with increasing exposure, a compensating developer provides less and less density increase per unit of exposure. Usually this is done by using a weak solution so that the developer exhausts in highlight areas between agitation cycles; a similar effect can be achieved by using a developer that modifies the curve shape to about the same without relying on exhaustion. A compensating developer may or may not be useful. While compensation may bring the highlights down to printable densities, highlight contrast may then be so low that virtually no detail is visible.

-- John Hicks / John's Camera Shop (jbh@magicnet.net), July 09, 1999.

in other words,, DK-50 . is a compensating developer or self masking.

dr

-- drwood (drwood@drwood.com), July 10, 1999.


Richard, in addition to the first answer posted, the compensating developer will help to keep a better level of shadow contrast. This will bring out better seperations in the shadow areas of your print without making the highlights too contrasty. overall i find this to be a most desired effect in making my prints look very snappy, and alive. tho there are situations where i would prefer to have a softer effect.. and will use a different type of developer. Sean.

-- Sean (ZBeeblebrox42@yahoo.com), July 12, 1999.

Thank you all for your answers. May 99 I shot tornado damage here in Oklahoma with cloudy skies part of the composition. I developed FP4 in Rodinal 1:50 to capture a long tonal range. The negs still require about 40 secs of burning in (later shots using a yellow filter helped). What are good situatiions to use a compensating developer if highlight details are at risk????

-- Richard Jepsen (richard.jepsen@tinker.af.mil), August 05, 1999.

Thank you all for your answers. May 99 I shot tornado damage here in Oklahoma with cloudy skies part of the composition. I developed FP4 in Rodinal 1:50 to capture a long tonal range. The negs still require about 40 secs of burning in (later shots using a yellow filter helped). What situations call for a compensating developer if highlight details are at risk????

-- Richard Jepsen (richard.jepsen@tinker.af.mil), August 05, 1999.


Are the highlight details you're referring to the sky in your prints? If you're exposing for detail on the ground - the damamge done - getting detail in the sky (B&W) often requires filtration. If you like what yellow does for the sky you'll love red, and when you get your hands on a polarizer, watch out - all your shots for a period of time will have a strange, lunar quality about them...have fun.

I think that if you wish to control contrast in your negatives, read about the chemistry going on. As has so often been recommended, read Ansel Adams, The Negative, and The Print for a laborious but excellent discussion of the subject matter. On a more practical note, overexpose your shots by half to a whole stop then under develop by, oh, 15% as a starting point - TEST YOUR OWN SETUP - and you'll compress the contrast range of your negative, reducing the contrast, while retaining highlight details...this may or not be what you really want in the subject matter you're really after - the damage. Do consider filtration for the problem you're talking about.

-- August Depner (apdepner@uswest.net), August 24, 1999.


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