Q. What do you think about these one-hour processing establishments? Do they do good work? Are they more expensive than most drug stores?

A. I've had great results from them. I admit that I was a little worried when I dropped off my first roll, but so far things have gone well. I've taken rolls to four different places (two separate processors) and I've been delighted with the results.

At all four places the prints were ready on time (or very close to it), the people were polite and efficient and the machinery worked well.

Prices were competitive, even for two prints off each negative.

One of the places offers a second set of prints free on Thursday. And another store is now offering one- hour enlarging service, but I haven't tried that yet.

All sell their own brand of print film, which I've heard good things about. I'm trying some now.

The flip side of this is that several of my friends have complained to me about mishandling of film and poor results from some one-hour shops. From what they've told me, most of the problems sound like machine breakdowns. But this can happen in a giant facility, too. PARING EXPENSES

Q. I'm a novice photographer who would like to do more, but I have limited financial resources. Film and processing are expensive, even though I look for bargains. How can I cut down on expenses?

A. This is is a tough one. I'd like to jump right in and tell you a thousand ways to save money.

I can't.

Photography can be more expensive then other hobbies. But, because its rewards are so great, I urge you to stay with it.

The first thing you should do is learn to curtail waste. Load your camera carefully -- you can frequently get an extra frame or two out of a roll. Don't overshoot -- study your subject longer and get a good idea of what you want to snap.

Continue to keep your eye out for processing specials. And join a camera club to take advantage of the many money-saving ideas that are exchanged at club meetings. You can find clubs at schools, community colleges and some government agencies. OLD FILM

Q. From time to time I see film for sale at a very good price; sometimes as much as one-half off. The catch is that it has passed the expiration date listed on the side. Realistically, how much out-of-date can that film be to remain a bargain?

A. Realistically, not very much out of date.

Take a look at some film that's not out of date. Frequently you'll find the expiration date two years away. This means that out-of-date film on sale has probably been sitting around on someone's shelf for at least two years.

That's a long time. It may have been stored correctly, but then again, it may not have. I like my film as fresh as possible, even at full price. FLASH POINTS

Q. Can you tell me what TTL is? What does it do? How is it better than just plain automatic dedicated flash? Is it worth the extra money? Someone told me it was good for flash fill. Is that true?

A. TTL (through the lens) flash is indeed very good. In almost every case I would recommend it.

TTL makes use of the camera's internal sensor to tell the flash how much light to put out. It integrates readings of existing light and flash to give just the right amount of light to provide good color. It's very effective, and it does a great job on flash fill. It can, once you get used to it, make your picture look as though you haven't used flash at all. Harsh shadows are eliminated and you get just the proper fill for back-lit subjects.

Still another advantage of TTL is that when it is used with a camera it was designed for, it automatically sets the exposure for you. In such cameras it also transfers the ready- light to the camera's viewfinder so you know exactly when the flash is ready to go again.

Dedicated flash is similar. It, too, makes flash shooting easy. With dedicated flash, however, you generally have to set your own f stops according to the flash guide.

Carl Kramer, former director of photography for The Washington Post, will try to answer your photography questions in his column, but cannot reply individually. Send your questions to: Carl Kramer, c/o Weekend, The Washington Post, 1150 15th Street NW, Washington DC 20071. PHOTO CONTEST -- The Antietam Photographic Society in Hagerstown invites amateur and professional photographers to submit color and black-and-white prints and color slides to its 10th annual Photographic Salon. The maximum number of entries in the contest's four categories is 16, with a $2 entry fee per slide or print. Entry deadline is September 15; judging is September 22. Entry forms are available at some Hagerstown photo supply stores or by calling 301/842- 2898, 301/824-7857 or by writing to P.A. Smith, 27 North Mill, Clear Spring, MD 21722.