Q. I've heard that Eastman is coming out with a new film speed marking called ISO. What about it? A. ISO, which will be a film-speed designation printed on Kodak films in the next few months, stands for International Standards Organization. It will eventually replace ASA N American Standards Association) markings. i

The ISO speeds are the same as the ASA and for a while both ASA and ISO markings will be carried on the film boxes.

There will be an additional change. The DIN (Deutsche Industrie Norm) rating will no longer be DIN but simply a degree symbol [CHARACTER UNKEYABLE]. Again, this too will be duplicated during the transition.

All that this means to the lay-user is that new film boxes will carry both designations. That is: for the new ASA 400 Ektachrome the label will read: ISO 400/27 [CHARACTER UNKEYABLE]. -- ASA 400/27 DIN.

The new label won't affect any of the facts: it's just an Eastman Kodak fancy. Q. When I take a flash shot of a long table of people my exposures are either too light in front or too dark in the back. It's an automatic camera -- so why doesn't it give me good exposure? A. There's just no way that you'll get even exposure on an in-depth flash picture, automatic or not. The reason is pure physics -- the intensity of light falls off in proportion to the square of its distance from the subject. This means that someone sitting six feet away (6x6 equals 36) is getting only one-fourth the light that falls on a person sitting three feet away. (3x3 equals 9). Obviously the light intensity won't be even.

There is a solution. Don't try to shoot straight down a table. Rather, stand off at an angle and take in only the people on the other side of the table or, if you want everybody, stand up on a chair so that you increase the distance from your foreground subjects in relation to the background. This won't give you a completely even exposure, but it will be better than from you own height level. Q. I know that you have done this before -- but could you please repeat the information on camera clubs one can join and photo contests to enter? A. The most active and largest (international) camera club in the PSA, the Photographic Society of America. Active local chapters conduct photo contests, bold meetings and exchange information. For information on membership and the location of your local chapter write to Membership Department, PSA Headquarters, 2005 Walnut Street, Philadelphia, Penn. 19103.

From time to time I publish information on photo contests that I feel are legitimate and worthwhile. One of these is the Ilfo-speed 1,000 British pound Print Competition. The advantage to this contest is that all you need to do is make an 8" x 10" unmounted print from your favorite negative on Ilfospeed graded RC paper or on Ilfospeed Multigrade variable contrast RC paper. They don't want your negative.

You can get entry forms from your local dealer or write to Ilford Inc., West 70 Century Road, Parmaus, N.J. 07652. The contest is open to pros, amateurs and students, with each competing in separate categories. Q. Recently I purchased an automatic electronic flash unit that uses a circular slide rule type of f/stop calculation. This calculator doesn't have all the ASA film speed numbers on it. For example: There's an ASA 25 but no ASA 32; it has an ASA 64 but lacks an ASA 100. How can I adjust it for the ASA settings that are not marked? A. About the only way you can figure the unmarked ASA settings is to interpolate between the marked numbers and make your own calibration. Make two marks equidistant between ASA 25 and ASA 50. These would correspond to an ASA 32 and an ASA 40 setting. Then follow this system throughout the other settings. That is: between 50 and 100 would be 64 and 80, between 100 and 200 the marks would correspond to 125 and 160, and from 200 to 400 the two inbetween settings would indicate 250 and 320.

These very same ASA number settings, by the way, also correspond to those unidentified marks on the ASA dial settings of 35mm cameras.