Kodak and Ilford density differences

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after exposing a roll of Tri-X, FP4+, HP5+, and Delta 3200, my observations show a distinct difference in the density of these films. the Tri-X exhibits a very nice, charcoal gray to black negative, whereas the Ilford films are much more of a subtle dark gray. it also seems to correlate with film speed, as the FP4+ is the darkest, Delta 3200 being quite thin. I have explored EI values, purposely overexposing at times, in an attempt to increase density. part of the difference may be from a slight purplish tinge on the Ilford films that exaggerates the look on the light table. Tri-X is very dark black on a clear base. they all seem to scan well, excepting the Delta 3200 that is very thin, and very grainy. this isn't an issue of underexposing, as I have bracketed during my tests and only extreme sunny skies come close to yielding the dark black shades of Tri-X. any observations regarding Agfa or T-Max films in these terms? are these findings observed by others?

-- Daniel Taylor (aviator@vernonia.com), June 28, 1999


Ilford publishes the characteristic curves (density over rel. log exposure) in their technical data sheets (see www.ilford.com, under products). From that material it appears that the curve of the Delta 3200 is less linear than that for the Delta 100 and 400, and does not reach so far up. However, I don't know how it compares to Kodak products, because I have been using the Ilford stuff over a long time with excellent results, and it would take some time for me to get the same experience with other materials.

Two other things come to mind, however:

1) You are comparing a high-chem emulsion to conventional emulsions by visual inspection. A densitometer or a lab meter might reveal that the differences appear to the naked eye only.

2) Can you rule out underdevelopment of the Delta 3200? If it consistently lacks the high densities, that might be the reason. Again, using a densitometer (or a lab meter), this time to determine the gradient, might give an answer.

-- Thomas Wollstein (wollstein@compuserve.com), June 29, 1999.

The effective speed of Delta 3200 is really around 1000. I've been shooting it at 800 and developing in PMK with very good results. The D-Min (base plus fog) is very high on it. I have had to use a grade three paper for most of my prints, but they look great, and they're sharp (I'm shooting 120).

-- Ed Buffaloe (edbuffaloe@earthlink.net), June 29, 1999.

Daniel, my tests on the Ilford Delta 3200 lead me to believe the same as i believe about TMZ. Only it is not as punchy. if you want to process it as if you shot it at 3200, expose it at 1600. this will fix the density, shadow detail, tonal values, and minimize the effect of the developing fog. if you are using a flash ( don't ask why people do it ) then rate it at 3200. if you use a fill or bounce card - 2000asa , or are shooting in extremely contrasty lighting- 2500asa. and as before mentioned another photographer, it's nominal speed is probably 1000 ( like t-max ) tho i have read no ilford publication to confirm this. Sean.

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

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