Dense Negatives and other Questions

[photomc]

Since I am starting to feel as Dense as my negatives have a few questions.

When a negative is described as dense, I would observe that the negative in question is thick - ie when held up to light there are very few areas that are clear (which in turn print dark - right?), and the overall negative will print lighter.

Ont the other hand, when a negative is thin, the over all negative has very few that 'block' light, which in turn means the negative would print darker?

So, if I haven't messed this up so far if many of my negatives were to be described as dense What should my next reaction be relative to film exposure/development? Should I increase/decrease exposure or increase/decrease development time?

Apologize for the basic nature of the questions, somehow I keep struggling with exposure concepts.

Thanks for the input in advance.

 

[TPPhotog]

Mike my understanding is that you need to use the frame numbers as reference. If your negs are dense, look at the numbers and if they are dark and spreading out then cut your development time. If the numbers look crisp or even light then you are over-exposing.

There again regardless of them being thin or dense, if I have the details and look I want from my prints then I don't worry about the text books. It's back to personal preference and how much detail you want in your shadows / highlights.

Bet I get shot down for this advice

 

[Dave Parker]

I have always been taught that the darker the negative, the more over exposed it is, which will result in a lighter positive, the lighter the negative the more underexposed it is hence the darker the positive, dark negative equates light positive, light negative equats dark positive, in very simple terms, if the negative is dense, it is overexpose, if the negative is light, then it is underexpose, and both situations will create the exact opposite on the positive paper.

And I know this is about as clear as mud.

Dave Parker
Ground Glass Specialties

 

[Flotsam]

If the negative is dense overall, reduce your exposure by increasing the rated film speed. Or re-examining your metering techniques.

If you're shadows (Thinner areas in the negative) look good but your highlights are dense, then reduce your developing time

 

[TPPhotog]

Dave strangely I understand what your saying. What I'm thinking is that if you expose for the shadows the negs will be overexposed unless you pull the dev. time to bring the highlights back in.

oooops Neil we posted about the same time LOL

 

[mikewhi]

Dense negative: right, one that blocks light when you try to look\print thru it.
It does not necessarily mean that the print will end up lighter, after all one can burn in. The degree of density is what distinguishes a negative as being dense - that is, it is uniformly of a density that would be difficult to print thru. If you can't read newsprint thru the most dense parts, then it is getting up there.

Thin negative: One that passes more light thru and has no areas that are very dense.

In printing, one usually employs assorted techniques to overcome the problems each introduce.

If a negative sis VERY dense all over, then exposure is the problem. It is possible that a negative can be overexposed to the extent that even the shortest development times will result in a dense negative. If the thinner areas of a dense negative (which print as shadows\blacks in the print) seem to have the correct amount of detail and can be seen thru ok, then the exposure is correct but the development time is too long. It is the amount of development action that builds up these dense negatives that were correctly exposed.

A thin negative can be created via underexposure and\or underdevelopment. Either one of these can do it or both in combination can. If the negative is uniformly thin, it was most likely underexposed and underdeveloped. If it has no detail in the thin areas at all but some density in the areas that would normally print as a mid or light tone, then it was underexposed and probably underdeveloped.

A thin negative can be salvaged by printing on contrasty paper and doing a lot of dodging. You can employ other techniques like bleaching to create whiteas that aren't in the negative.

Or one can scan the whole thing into PhotoShop....er, I'd better not go there.

For 35mm\roll film I always felt slightly thinner negatives were better to have than dense ones. Much easier to print from thinner negatives for these small format. They are enlarged so much anyway, that printing thru that extra density just results in even more apparent grain in the print.

Hope I haven't confused things. I'm sure others will explain it better.

-Mike

 

[Donald Miller]

Mike,

As others have related, a dense negative can be due to over exposure, over development, or a combination of both.

What I would do in evaluating a negative is to determine the amount of detail that is present in the least dense of the negative areas. This will be the amount of shadow detail. If there is no detail and your negatives are otherwise quite dense the density of the negative will most probably be due to overdevelopment. This negative would probably exhibit increase contrast or density range.

If your least dense areas on the negative are fairly dense and by this I mean .30 or .40 (compare to a .30 ND filter) then the dense negative is most probably due to overexposure. This negative if not overdeveloped will require long print times with lower then normal contrast and hence will require higher filtration or paper grade.

If your negative is dense as in the example directly above with close to normal contrast in applications where you are enlarging the negative. In other words it is dense but has normal contrast then it may be due to a combination of overexposure and overdevelopment. The reason that this is true is that an overexposed negative will typically push the highlight densities onto the shoulder of the film H&D curve.

This has really become confusing terminology, in my opinion, because of the tendency that some have to use "dense" interchangeably with "density range" or what has historically been called contrast. This interchangeable use of terms seems to have become very prevalent with the advent of increased interest in Azo. The first place that I encountered this loose use of language was in the writings of Michael Smith on Azo. It doesn't necessarily take a dense negative on Azo. It takes does however take a negative with density range to match the paper.

 

[photomc]

Mike,

This has really become confusing terminology, in my opinion, because of the tendency that some have to use "dense" interchangeably with "density range" or what has historically been called contrast. This interchangeable use of terms seems to have become very prevalent with the advent of increased interest in Azo. The first place that I encountered this loose use of language was in the writings of Michael Smith on Azo. It doesn't necessarily take a dense negative on Azo. It takes does however take a negative with density range to match the paper.

Thank you Donald, this may be why I keep getting confused...among other reasons. When I evaluate a negative I expect, based on the exposure given, that there will be some detail in the shadows (lets say Zone II or VI) and the highlights will also have some detail (again close to Zone VIII). If you recall the White Church thread and posted image this is pretty much what happened and the negative prints well. At other times, it seems like to get the shadows right then the highlights go to Zone IX or higher.

Could this be corrected during development by increasing the development time? Or have I got it backwards and I need to decrease the development time. Should note here that currently I am using FP4+, and wonder is another film with a longer toe would be better.

Thanks to everyone that has commented so far, sometimes it just helps to hear how others state things to make sure you aren't out in left field somewhere...of course the light can be very nice in left field this time of year.

Should also note that I have started to do more sheet film now and so there are no codes, marks to compare to.

 

[Donald Miller]

Thank you Donald, this may be why I keep getting confused...among other reasons. When I evaluate a negative I expect, based on the exposure given, that there will be some detail in the shadows (lets say Zone II or VI) and the highlights will also have some detail (again close to Zone VIII). If you recall the White Church thread and posted image this is pretty much what happened and the negative prints well. At other times, it seems like to get the shadows right then the highlights go to Zone IX or higher.

Could this be corrected during development by increasing the development time? Or have I got it backwards and I need to decrease the development time. Should note here that currently I am using FP4+, and wonder is another film with a longer toe would be better.

Thanks to everyone that has commented so far, sometimes it just helps to hear how others state things to make sure you aren't out in left field somewhere...of course the light can be very nice in left field this time of year.

Should also note that I have started to do more sheet film now and so there are no codes, marks to compare to.

Mike,
I understand what you are asking now. If you have a scene such as a church scene, for instance. In this scene let's assume that you want to show no detail in minute areas like a door knob...then don't worry about where they will fall on exposure. But in this same scene you want to show detail in the stained glass windows, for instance, and you want these to render a Zone IV print value. Then expose your film at that exposure.

Taking this a step further that when you check the white siding of the church, with your spot meter, you find that it indicates a Zone X exposure. You know the white siding will not, under normal development, render with any detail at that value. So the answer is process for N-2 development so that the siding values come down to a Zone VIII tonal value. In other words decrease development to bring high contrast down. Increase development to bring flat contrast up.

Ilford FP4 is a good film. It is adaptable to modifications of contrast through altered development.

 

[stephen]

Quite a number of books on processing give examples of the effect of varying exposure and development. If you can find an old copy of "Basic Photography" by Michael Langford, there is an excellent two page spread showing the same scene six times: three to illustrate the effect of exposure alone, and three to show the effect of development. Both accompanied by the film's characteristic curve, annotated. This is in the 1974 edition. The current edition has dropped this, and dropped in value as a result in my view.

Let me know if you are interested enough to want further details on the book, or a scan of the pages.