Ive taken a sheet of film and exposed it to daylight (no camera) for a minute or two. When developed it yeilded a very dense black. I suppose this is the max black attainable with that film. However even when I over-expose a negative by +3 stops, I dont get anything near the max black.
So should I expect to see max black in a negative or is that unattainable (and undesireable) in a negative.
For traditional printing, it's all about shadow detail, contrast control, gradation, sharness, grain.
Maximum black on a negative???
If you obtain that kind of black you are talking about, your film is way overcooked. It is not recomended to expose that heavily because that will only compress the tones which gives you a horrible print. Much better to take care of your shadows by exposing properly so that they barely have density in the negative and work your highlights with developement until desired density is achieved. I assume you are printing on silver papers. For alternative proceses your dmax in the negative should be much higher.
Yes, I am printing on silver papers. I'm just trying to get a feel for what a properly developed and exposed negative should look like. I think this is a problem many beginners have.
My scanner has a hard time getting detail from flat negatives. But I want to make sure that I keep the highlight and shadow detail.
...should I expect to see max black in a negative or is that unattainable (and undesirable) in a negative?
You should not expect to see max black (Dmax) in a negative. It can be done, but is undesirable in a lot of ways. The old rule of thumb from my photo-journalism days is that you want to be able to read a newspaper through the densest part of the negative.
The reasons for this include reasonable printing times, reasonable range of tones for printing (really dense negatives result in prints with blown out highlights), excessive grain, loss of resolution, and on and on.
The reason you don't see Dmax for your negative even when you over expose by 3 or more stops is that most modern films have a tremendous amount of exposure latitude. I've heard (never run the tests myself) that 100Tmax has around 12 stops of latitude on the top end, but you'd have to use a carbon arc lamp to see through it.
Proper exposure for a negative is the least amount that will get the job done. This is why people expose for the shadows (to make sure they get shadow detail on the print) and develop for the highlights (to make sure they don't get blown out highlights on the print). If your negatives are more dense than needed, your get right back to increased grain, decreased apparent sharpness, etc.
Bruce Watson
I'm just trying to get a feel for what a properly developed and exposed negative should look like.
Ah, that. Many beginners think that a good negative should look like a good print but in reverse. I remember that I thought that anyway. Full range of tones. Solid black, solid white. All that.
Nothing could be farther from the truth. A good negative looks thin, and contrast looks weak. I remember looking at my first ones and thinking "I wonder what I did wrong." When I showed them to other, more experienced people, they all told me that what I had was just right.
It is not intuitively obvious. The point of a negative that looks the way I describe is that it will be easy to print on a #2 or #3 paper. As I said before, a rule of thumb is that you should be able to read a newspaper though the densest part of a negative. Other people can probably give you more, different, rules of thumb, I'm sure.
If you want to learn more, you can try Ansel Adams' book The Negative and other texts which will tell you in great detail all about what happens to a negative and how you can control and manipulate it, and why you want to do it that way.
Bruce Watson
I will have to look at Ansel Adams 'The Negative' again. Most of what I have read regarding the zone system and proper exposure requires the use of a densitometer. Since I dont have a densitometer, I have been trying to get a good feel of proper development. I can scan in the negs and look at the histogram, but negatives are much lower contrast than slide film.
You might get some meaningful info from some of the technique pages at Barry Thornton's (deceased) site. A good start is http://www.barry-thornton.co.uk/pfs.htm for determining a personal film speed. It doesn't require a densitometer and is good, solid information to build from. Snoop around the whole techniques area and read his no-zone system and personal developing time info. I'm embarrassed to admit how much time I've spent with densitometry equipment when I would have been off to a better start by following some of Barry's suggestions!
Darin -
The term "maximum black" applies to prints, not to negatives. Maximum black is the blackest density you can achieve on a PRINT exposed through unexposed but fully processed film (the edge, or "rebate" on sheet film, the narrow band between exposures on roll film, or unexposed frames on rollfilm). The normal application of maximum black is to determine the optimum exposure time for contact prints assuming that all other variables (including the lens aperture and elevation if you are using an enlarger as your contact printing light source).
I don't think you want to try for maximum black in negatives because the resulting negatives would be unprintable.
You basically have four variables to determine - negative exposure and processing, and print exposure and processing. The preferred sequence of testing and calibration is:
1. Determine negative exposure. Negative exposure should be based on achieving a Zone I shadow density that is 0.1 to 0.15 units above film base plus fog (ie, unexposed and processed film). This evaluation is ideally based on examination of the negative using a transmission densitometer, but there are ways you can do it by optical comparison. .
2. Determine maximum black on a test print - either a contact print, or an enlargement. This is done by visually comparing a series of test prints that have been fully developed, washed and completely dried.
3. Determine negative processing that will cause a print exposed at the maximum black printing time to yield a Zone VIII highlight that is just perceptably darker than blank white paper. You can do this scientifically using a reflection densitometer, but most people do it visually by comparing a series of test prints that have been fully developed, washed and completely dried.
4. Print development usually is not a scientific matter. Typically, you want enough development to assure that you get uniformity across the print and that you achieve reasonable print contrast. Typically, the mininum development time is around 2 minutes. But you can go longer, and good printers typically will develop their prints for 3-5 minutes. The limit is the point when highlights start to gray down. Most people develop a "sense" of what is right - they know they have to go for, say 2 minutes, and they also know from experience that they don't want to exceed, say 6 minutes, and then they make a judgement call somewhere in between based on their emotional reaction to the image.
Louie
Hi Darin,
If you have access to a lightbox and a 35mm or MF camera with spot metering you can use them to give you some idea of negative densities. Simply place a blank but processed negative (fb+fog) on the lightbox and take a meter reading. I carefully 'plonk' the camera lens (focus on infinity) on top of the sleeved negative so it's sitting on the lightbox and adjust the aperature, shutter speed and exposure compensation until I 'zero' the meter. Then place your test negatives on the lightbox and compare their meter reading with your base one. It'll help to read some of the previously mentioned references to the zone system but briefly, each 1/3rd stop is 0.1 units so for a Zone I negative you'll be looking for something around 1/3rd of a stop, erring towards 1/2 stop. For Zone VIII you're aiming for around 1.2 - 1.3 depending on enlarger which corresponds to about 4 stops with the meter. Another option is to use known neutral density filters and compare these (or combinations of these) with your negative. I realise it's not that accurate but it does help with ballpark figures and at least it confirmed my suspicions that I needed to reduce my film speed in order to keep shadow detail and increase my development time for the highlights.
Roger.
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