how to evalulateand compare negatives

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I have just started processing my own 35mm film (delta 100 in stock D-76 w/Illfords reccomended times) and so far so good, but I am having trouble critically evaluating the final results. I've read a few books on this (mainly the AA one) but they are long on talk and short on pictures of examples. Aside from reading newsprint through the darkest sections, how can I critically evaluate my negs (aside from obvious defects & severe over/under- exp/dev)so I can learn to see if they are poor, ok ,just good or great? I tried comparing them to what my local pro lab did to my other rolls of Delta 100 (they seem pretty close but mine are just a "bit" more contrasty) but is this a fair comparison? I've tried showing other people my negs but got opinions all over the map. Do I now have to buy a densiometer? Should I just try printing what I have so far? Thanks for any help.

-- bill zelinski (willy226@yahoo.com), August 19, 1999

Answers

Bill, It's way to early to start talking about buying a densitometer. The best advice I can give you is to start printing. That is what you are really after. Make sure that you make test prints on different contrast grades of paper. This will help you adjust your development times. If you are shooting 35mm your goal should be to print well on a grade 2.5 to 3 paper (or the same filter on VC paper.) If you find that your megs print better on a 1.5 or 2, decrease your development. If you find that you require a grade 3 or higher, increase your development time. If you are shooting 120, or sheet film, your goal should be grade 2. I suspect that you will discover that you have a little to much contrast and need to reduce development.

-- Ed Farmer (photography2k@hotmail.com), August 19, 1999.

As Ed Farmer said, the negatives that produce the good prints most easily are generally the ones to go after. One easy thing that you might try is making contact sheets of negatives that that you know print easily, and make others of the negatives in question, using the exact same exposure. You may already be way ahead of me there, but I print the contact sheets so that the film sprocket holes are just _barely_ visible. I have standardized the exposure of these, and it gives me quick feedback on how things are doing with density and contrast.

-- Paul Harris (pharris@neosoft.com), August 19, 1999.

Bill, While Ed Farmer is essentially correct, there is a bit more to the question of negative quality than he mentions. First, the "ideal" negative is the one which gives you the exact print you want. That is the operational criterion. Second, an ideal negative for a condenser enlarger is not the same as for a cold light or arc light enlarger. Both density and contrast are handled different by the two types of enlarger. Also, there is the issue of how much enlargement and image grain are involved. These will affect your processing and the appearance of the negative.Then there is the issue of whether you plan to tone the print. I could add a few more things, but you get the point. Evaluating negatives is an art not a science. When you are comfotrable with the prints you get, then you have a satisfactory negative.

-- Richard Newman (rnewman@snip.net), August 19, 1999.

If you really want to get into measuring the densities of your negatives, you can do it in less expensive fashion by modifying your spot meter (if you have one). Check out Phil Davies 'Beyond the Zone System' for details. Basically, it involves modifying the spotmeter for close up reading with a lens mounted backwards on it. However, it is somewhat debatable how much value that is going to add, unless you're into running tests on your negative material, development times and papers and plotting characteristic curves etc. I think you're better served by concentrating on printing the negatives you're currently getting. The 'reading print on a newspaper' is a good enough starting test. In ordinary room light i.e., not on a light table, lay the neg emulsion side down on a magazine page. If you can easily read the type, then the highlight densities are probably less than 0.8. A density greater than about 1.2 will generally completely obscure the type. However, at the end of the day, it is the print which matters. So print the negs you get and see if you're consistently having to use very hard or very soft papers and adjust development times accordingly.

-- N Dhananjay (ndhanu@umich.edu), August 20, 1999.

It is very difficult to discuss in a book (or Internet forum) what makes a 'good' or 'bad' negative. Such a discussion should really be interactive: with the actual negative (and 'straight' print) in front of us, we could discuss what you want, and whether the negative provides it.

Have you considered joining a club, or taking an evening course? The discussions with more experienced people can be very valuable.

Remember that the negative isn't the final goal, but a necessary step towards a print. If the print is excellent, then there can't have been much wrong with the negative.

BTZS is an excellent book, but not everyone wants to get into the science of densitometry and precise film speeds.

Perhaps the first evaluations could be:



-- Alan Gibson (Alan.Gibson@technologist.com), August 20, 1999.


thanks everyone, I plan on takkng some courses and hopefully meet some more experienced photographers. I'm also gearing up to print all of these negs so I can get some idea of how they all print. In "The Negative" Adams mentions a Kodak product, a type of "chart" or comparison step guide for evaluation of neg densisity, he does not give much detail but does anyone know what this is and if it would be useful?

-- bill zelinski (wily@yahoo.com), August 20, 1999.

I have only three of things to add to the excellent advice above: 1) Don't even think about 'evaluating' negatives. Make a 'proper' proof sheet (minimum time for maximum black through the film edges) on grade 2 (some people prefer to develop 35 mm for grade 3) and judge the proof sheet. 2) Stay away from D-76 and commercial labs; both will over develop your film. 3. Stay away, far away, from Phil Davis and his convoluted, BTZS gibberish unless you want to wind up going nuts!

-- Michael D Fraser (mdfraser@earthlink.net), August 20, 1999.

Phil Davis isn't so bad if you already know what you're doing in the darkroom. But you don't need to go there to process and print your negs correctly. You can read magazines through a neg and all that trash but the best way to read a neg is to print it. Come on now. Don't be afraid. It won't hurt you. And it's inexpensive. Oh. And D-76 is one of the best developers going. It's used with great success all over the world. Has been for decades. And very forgiving. So just plung right in and start learning the process of photography. Shooting is only the start. And to learn to shoot properly you should learn the entire system from exposure to printing. And it's very easy to do. James

-- james (james_mickelson@hotmail.com), August 21, 1999.

Bill, you asked a good question and you appear to have gotten some equally good answers, hints, encouragements, etc. My suggestion is rather simple: Spend less time worrying about good/bad negatives and more time in your darkroom (or someone's darkroom) actually developing prints. You'll find that there are as many ways to print a negative, whether it is considered good or bad, dense or thin, etc. You'd be amazed how you can print a good print from a negative so thin that your eyes can barely see any image. But printed through 200 magenta of filtration, you can achieve rich blacks and white whites and maybe even grays. Much of the fun of B&W photography begins in the darkroom. Close the door, turn on some favorite music, switch on the safe lights and go for it. Good luck!

-- Chuck Kershner (courierent@earthlink.net), August 27, 1999.

Hi, Just a short note to make you aware of another source for information about non-densitometer testing. The paper-based method described in the book "The Zone System Manual", by Minor White, Richard Zakia et al is one that I have used successfully for years now. It describes how to make Zone System tests for film speeds and all develpment options and requires nothing more than your negative, enlarger and paper, and, it's scientific!! Check it out. Regards, ;^D)

-- Doremus Scudder (ScudderLandreth@compuserve.com), August 29, 1999.


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