Q. I have a Minolta SRT-202 35mm. On two occasions the camera has jammed -- the film can't be advanced and the shutter can't be fired. I sent the camera back to the factory for repairs the first time (10 years ago). I accepted the problem and paid for repairs and cleaning.

This past March, when it again happened, I sent it back to the factory and asked why it repeatedly jammed. They just repaired the camera, charged me a "bench" fee and sent it back with no explanation.

Can you tell me if there is a way to prevent this jamming from happening?

A. I can't tell you specifically what happened to your camera, but I have found that, on rare occasions, a tiny film chip can break off, get stuck in a mechanism and cause jamming. The few times it has happened to me the only common denominator was cold weather. Despite the wonders of the modern films, very cold weather can make them a little brittle.

Load and unload your camera with extreme care. When shooting in cold weather, keep your camera as warm as possible in a pocket or under a jacket. In the bitterest of cold, I even wrap the cameras in my bag in a piece of an old nylon blanket while carrying them to and from a shoot.

From time to time, stop at your camera store and let them open the back and make sure everything is free from dust and film chips. Let someone with some experience and camera knowledge do this. It's not recommended for doing at home.

I really think you've done well with that camera. Ten years before a breakdown shows how well that SRT was made.

Q. My son has been taking a high school course in photography and having a great time with it. The problem is that he has developed a rash on his hands. He complains of itching from time to time but insists it's nothing to hamper his lab work. His uncle, a proficient photographer, says that this is an allergy to the developer used. Can this be true? I'd hate to discourage this interest in photography.

A. Don't discourage the interest, but take your son to see a doctor. I have seen this type of thing many times; in fact, I have lived through it myself. It's affected me less and less over the years; presumably I have developed an immunity to the chemistry that causes it.

Usually, people sensitive to photographic material can overcome it by simply wearing rubber gloves. If that's too cumbersome, thin plastic surgeon's gloves work well.

Q. Every once in a while I see AA batteries on sale. Do you think I ought to stock up during these sales? I would guess these batteries would last as long in my bag or on my bookshelf as they would at the dealers. I use a lot of them since my flash holds four and my camera two. I like to change batteries often in the camera and have to change them often in the flash.

A. Depending on how much you save and how many you like to keep on hand, I suggest you go slowly. These batteries are always available, no matter where or when you travel. Besides, they will move faster from your dealer's shelves than from yours. Generally, the batteries you buy on a given day are fairly fresh and trustworthy.

If you have already bought a supply of batteries, be sure that you store them in the refrigerator. Mark the date on each package so you'll know the proper order to use them.

One other warning: Once you have started to use a set of batteries in your flash or camera, they will continue to discharge. So if you haven't used the flash or camera in some time, be careful that the batteries haven't worn down. And, if you don't plan to use your equipment for a while, take the batteries out so that they don't corrode and ruin something.

Q. I have a Minolta Freedom Dual compact camera. I recently took some pictures of a squirrel running around in my back yard. I took them through the storm door and none of them came out. They were blurry and very light. It wasn't the fault of the camera because I also took a couple of pictures from outside and they were okay. What did I do wrong?

A. You didn't do anything wrong, but have learned something very important about modern technology. The new "point-and-shoot" cameras focus by means of an infra-red beam. It travels from the camera to the subject and back again, setting the exposure and proper lens to subject distance.

The trade-off for all this wonderful simplicity is that the infrared beam doesn't work in some instances. Sometimes shooting though glass distorts the beam and the automatics of the camera don't work. This is what happened in your case.

Write Carl Kramer c/o Weekend, The Washington Post, 1150 15th St. NW, Washington, DC 20071.