Contrast ?

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I've just processed my first film, and it has come out quite grey on the neg.

I used Ilford HP5 400 film and developed with DDX as per instructions on the bottle.

I would basicly like to know what causes the shots to be so washed out so I can go back and improve. I'm a little upset as some of the shots where good (even for me). But I did expect my first couple of films to be a little dodgy.

I've started using a 25A filter to try and improve the contrast.. but I'm pretty sure my problem was becuase I either under or overdeveloped the film. Could this be the case?

-- Kent (kchalmers@toshiba-tap.com), November 26, 2001

Answers

This sounds to me like fog, whether is chemical or from light is difficult to tell with your explanation. So, does the entire negative looks like it is gray and even? if so, then it probably is cehmical fog from the developer, and/or outdated heated film. If it is from the developer i would think is overdevelopment with too strong a developer. If you see streaks then it probably is a light leak.

I hope this helped, if you can be a little more precise about the appereance of your film we can probably help you more.

-- Jorge Gasteazoro (jorgegm58@prodigy.net.mx), November 26, 2001.


Thanks Jorge,

From memory I'm sure that even the borders were grey they have good definition, no streaks at all and I used a brand new bottle of developer. So I think I might go back and develop another film for less time than stated...

-- Kent (kchalmers@toshiba-tap.com), November 26, 2001.


Here is a quote from the HP5+ data sheet on the Ilford website: http://www.ilford.com/html/us_english/pdf/HP5_Plus.pdf

"Cameras with through-the-lens metering will usually adjust the exposure automatically when using filters. With some automatic exposure cameras, the correction given for deep red and orange filters can produce negatives under exposed by as much as 1 1/2 stops."

I would run some tests using a gray card (or something in the middle gray area) to see what the real difference is with and without the filter. This will require you to take one shot without the filter and multiple shots (with varying exposure adjustments) with the filter to see which adjustment needs to be made.

There will likely be a difference depending on the nature of the light. In some areas (such as Colorado where I live) there is an abundance of blue light, especially in shadows on a sunny day. This requires me to make a larger adjustment than may be required in some other locations (like Rochester NY or anywhere in the UK).

As far as under/over development is concerned: if that is the problem it is probably underdevelopment, but I would work on the exposure first.

-- Michael Feldman (mfeldman@qwest.net), November 26, 2001.


If even the borders are gray then it is fog, and most likely chemical fog from your developer. Although Feldman makes a good point, If it was underexposure and/or underdevelopment, your borders would look clear, since they are also gray I vote for either chemical fog, or a bad film that is either too old or has been exposed to heat.

-- Jorge Gasteazoro (jorgegm58@prodigy.net.mx), November 27, 2001.

I wasn’t sure what was meant by “even the borders were grey.” Is that inside the image area or outside the image area (which should be relatively clear)?

-- Michael Feldman (mfeldman@qwest.net), November 27, 2001.


Is this greyness clear, or cloudy?
If it's cloudy then it's almost certainly due to insufficient fixing. Put some of the negatives back in the fixer for 5 minutes and see if they improve. If they do, then re-fix the entire batch, and then wash and dry them again.

-- Pete Andrews (p.l.andrews@bham.ac.uk), November 27, 2001.

Pete makes a good point, if the grayness is clear I would guess fog, if it is cloudy then maybe it is insuficient fixing time.

-- Jorge Gasteazoro (jorgegm58@prodigy.net.mx), November 27, 2001.

You have a lot of good advice above, but one point in your post caught my attention. You mention that your shots are "washed out". To me that would indicate that the problem you have is thin, flat (no contrast) negatives. Not that you have any fogging problems.

I have started teaching darkroom work and it has been very interesting to see a lot of students working in B&W for the first time. The most common problem that I see is underexposed film. Underexposed film requires more development to increase contrast.

My first sugestion would be to forget the 25A until you are getting better results without it. Go shoot another roll of film. The entire roll should be shot under similar lighting. Shoot the first third of the roll with the film speed set at 400, the second third at 250 and the remainder at 160. These are broad steps, but will give you a good idea of where your true film speed will be. Process this roll exactly like you did the last. See if the alternate settings look better. If the over exposed frames look better that the first frames, you can either adopt this new speed for HP5, or do some more experimantation with longer developing times.

In any case, make sure that you come back here and let us know what you have discovered.

-- Ed Farmer (photography2k@hotmail.com), November 27, 2001.


Thanks for the stacks of advice, I'm working from memory as my negs are at my Parents house but I have some of the prints at home.. I'll go and dig up some of the prints I have. Would it make sense to scan them and post a link.. see if that helps us at all?

-- Kent (kchalmers@toshiba-tap.com), November 27, 2001.

Not really Kent, as the printing process can accomodate a wide range of negatives, it might show how good a printer someone was to recover the situation. There's just to many variables involved. Wait till you get hold of your negs and report back (IMO)

-- Nigel Smith (nlandgl@unite.com.au), November 27, 2001.


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