Posted by Nathan McCreery on April 26, 2017
One of the most basic things necessary (to get the image you wanted when you made the original exposure) is to determine what exposure will give the optimum information on your original piece of film. That principle holds true even in the digital realm. It is only handled in a different way.
Exposure In The Shadows
Usually, 95%+ of the time when using black and white film the exposure should be based on the detail we want in the shadow areas of the negative, or the shadow areas of the image. All density in the shadow areas of an image are based on film exposure. You cannot, through extended development, add detail to the shadow areas of the image. The reason for that is very simple. The shadow areas of the negative develop completely after only a short amount of contact with an active developer solution. That principle is true no matter what black and white film you are using and no matter what film developer you are using.
While it is true that some developers are more active than others, and you can actually have slightly different ASAs for your film with different developer formulas, the deepest shadow areas will develop completely after a short time in contact with an active developer solution. This is somewhat a controversial statement among some photographers, but because of that principle it is impossible to "push process" film. The real ASA or ISO of the film will not change no matter how long the film is in the developer solution.
With that principle in mind I always use the darkest part of the scene, where I will want detail, as the basis for my exposure, since detail will not be in those areas if the exposure isn't strong enough to push enough light into those areas for them to be exposed. Understand also, while we are on this topic, that it actually possible to expose film to light but the light level is so low that the detail, while it can be seen on the negative, will not be printable. It will only print as black.
The Truth About Film Speed
The next thing to understand is that the ASA/ISO or EI of film is almost always different than what is referred to as "box speed". For instance, I use Kodak T-Max 100 film. Years and years of using the film has taught me that, even though the published ASA of the film is 100 it's useful ASA is, in my case, 50. Other photographers may rate the film at an ASA of 64 and others at 80. Only experimentation by you can determine what the actual useful ASA is for you with any given film. There are people that claim that some of the Ilford films have the true "box speed" ASA. I am skeptical about that and would never use any new film without some experiments to determine the accuracy of the film's rated ASA.
Using An Accurate Exposure Meter
The next thing that must be taken into account, in this regard, is the accuracy of your exposure meter. I have three meters that I use. One is my main meter, a Pentax Digital Spot Sensor. I use it 99+% of the time, simply because I have used it so much that I know what its prejudices are, and usually can compensate for them. The other meter that is always in my truck in reserve is a Soligor Digital Spot Sensor. Neither of these meters a made anymore, by the way, but I do see them on e-Bay with some frequency. The Soligor is an excellent piece of equipment and represents a real bargain if you can find one in good condition. The thing to note here. Both meters are calibrated. Neither meter gives the same reading as the other one. Again, you have to experiment a bit to understand what your meter is doing.
Limit the Amount of Film Stock Variables
As you might surmise, there are a number of variables in the process of exposing film that have to be accounted for if you are to expect consistent and predictable results. For the reasons I have stated I think it's a good idea to find a film you like, that you will be able to acquire easily, and use it for all of your work until you know it inside and out.
BTW, I do think it's a very bad idea to cruise e-Bay for bargains on unfamiliar films since the variables about those films are usually unknown. It is a good idea to purchase your film only from sellers that are known to sell a lot of film, that stores their film properly and will send out the film in a timely manner. You don't want to get a batch of film that is five years out of date and has been stored in the trunk of someone's car at 100+ degrees for the last four years.
The next issue in getting really good, printable negatives is development. Of course all film has to be handled in complete darkness only. Any light that invades the darkness will degrade the quality of your negatives. Total and complete darkness only!
Getting Control Over the Development Process
As I said earlier, the darkest portions of your negative will develop completely in a very short amount of time. The other part of the equation is that the highlight portions, lightest areas, of the image will continue to develop as long as they are in contact with an active developer solution. The more control and care you exercise over the development, and overall processing, of your film, the higher quality your negatives will be. It is important to control your films processing as precisely as possible. The reason is simple, and if film exposure is the right hand, then film processing is the left hand. The two have to work together, very precisely, if the negatives you produce are to be easily, or even not easily, printed. It should be noted that it is actually quite easy to produce a black and white negative that simply cannot be printed if things are not kept is control.
When processing film the temperature of all solutions must be controlled as closely as possible. Time must be controlled, especially in the development stage. Processing agitation must be consistent from batch to batch. Whenever possible use only distilled water, especially on the chemical steps.
Every Step of the Way
Never take anything for granted. The more precise you are in the development of your film, and the more precise you are in the exposure of your film, and the more repeatable you are in all of your processes the better prints you will produce, and the more expressive you will be able to be in making those photographs.
About the Author:
Nathan McCreery creates exquisite photographs of the American West, and a few other places. Nathan has been selected as Artist in Residence several times by the National Park Service. The latest Residency was served in Buffalo National River in Arkansas. He has been the recipient of the Eliot Porter award by the Professional Photographers Association of New Mexico and has received the Kodak Gallery award for photographic excellence several times.
To see more of Nathan McCleery's work visit: http://www.nathanmccreeryphotography.com/