A camera for a dollar? A roll of film for a dime?

Well, that was the Eastman Kodak ad for Brownie cameras in 1900. How times have changed.

Today the equivalent Kodak cheapie is the Ektra 200 at $24.50 and for the more sophisticated snapper, the Tele-Ektralite 600 at 66.95 -- and you can pay more, but these are the popular models.

Film? You wouldn't believe it -- unless you just bought some. As of this writing, 110 film for the new cameras runs $1.33 for a 12-exposure roll of black-and-white and $2.26 for a roll of 24-exposure color. And we're talking about itty-bitty film of 110 size, not the 2 1/4" x 2 1/4" frames that the good old Brownie used.

But wait -- there's more: The cost of development is where the "ouch" comes in.

The very same Brownie ad of 1900 offers a developing and printing outfit for 75 cents so you can "do it yourself" -- but today, who does? We all send out to the lab. And average lab costs are $1.50 to develop a roll of 12-exposure black-and-white and 35 cents per print for each enlargement to 3" x 5". That makes it $7.03, or 58 cents per print from the 12-exposure roll.

Popular color, by contrast, is a better buy. At $2.36 at a 24-exposure roll of Kodacolor plus $9.05 for 3 1/4 x 4 1/4" prints the per-print price comes to 47 cents.

And I'm sure that the results from the good old Brownie were not as good as from today's Instamatics -- or, for that matter, from the more sophisticated 35s, but it does cause one to wonder where the photographic bargains are in today's inflationary times.

Here are some thoughts on how to save photographically:

You're shopping for a new SLR, don't buy the top of the line -- only the extra gadgets you really need. A loaded camera is like a loaded car: a good way to jack up the price for the same essentials.

When looking for lenses, settle for the next slower f/stop. The price difference can be considerable, and when was the last time you made a picture at f/1.4 instead of f/2?

If you're a big film-user, load your own. You can buy bulk film and a oader -- just check Popular Photography, Petersen's and other magazines. And even if you're not a big shooter, shop around. The same film may be a loss leader elsewhere.

Try developing and printing your own film. Color today is just as easy to process as black-and-white -- and besides, you'll have the fun of doing it.

To make your flash shots count, get a flash with an auto sensor. There are now light, relatively cheap models, like the Vivitar 2500 Zoom Thyristor.

Don't get an auto-wind unless you don't want to save on film. This gadget is fine if you're a pro covering sports or other fast-moving events -- not for casual and occasional shooting.

If your camera is working and you're happy with it, don't think that your pictures will turn out better with a new model. Invest in a how-to book instead, and you'll get a picture face-lift out of the old one.

These are not drastic solutions, but common-sense avoidance of excess cost and waste. I'm sure you know of others -- let's hear them. Q: This summer I'm going to London. I want to be sure to come back with some good shots of the changing of the guards at Buckingham Palace. Do you have any suggestions ? A: Yes, and I'll quote from a book I helped write:

"Shooting the changing of the guard at Buckingham is quite simple provided that you get there in time, as there are thousands of other photographers who have the same idea. The guard change is at 11:30 a.m. daily, and you should be there by at least 11 o'clock to get a frontrow spot.

"If you get there late, don't despair, just walk up the steps of the facing Queen Victoria Monument and shoot over the heads of the crowd. Another tip is that the guards come out in two identical groups and separate to the right and left on leaving, so if your position isn't dead center you can still get the same shot from either side."

A bonus tip, also in the book, is that if you can arrive at Buckingham by 10:30 a.m. you can take a shot of the mounted Horse Guards on their way the Whitehall. This is a much better shot than at the guard change itself, since at Whitehall the quarters are confined and the horses are not in action. The Horse Guards trot by at 10:30 a.m. and the best place to shoot this is on the Mall in front of the Victorian Memorial. Just walk down the Mall facing Queen Victoria, trots by. After this you'll have plenty of time to walk back to the front of Buckingham and shoot the changing of the guard. Q: In a previous column you mentioned several books on filters and special effects. Would you please repeat these titles and where I could send for them ? A: The best place to shop for books and filters is at your local camera store, since there you can review the books and try out the filter effects before buying. But if you can't do this and prefer shopping by mail, here's a list of addresses for some of the major publishers and manufacturers' reps where you can write for catalogues and information:

AMPHOTO, 2160 Patterson Street, Cincinnati, Ohio 45214 (a particularly good book is The Tiffen Practical Filter Manual , By Robb Smith, for $5.95); HP Books, P.O. Box 5367, Tucson, Arizona 85703 (How to Create Photographic Special Effects , by allan Horvath, at $7.95); Petersen Publishing Co., 8490 Sunset Boulevard, Los Angeles 90069 (Special Effects , by Ken Biggs, at $2.95).

Places to write for filter information are Hoya, Uniphot Inc., 61-10 34th Avenue, Woodside, New York 11377; Tiffen Manufacturing Corp., 71 Jane Street, Roslyn Heights, New York 11577; and Spiratone, Inc., 130 West 31st Street, New York 10001. Q: My flash pictures seem so flat and dead. Is there any way I could pep them up ? A: A good way to put added life into flash shots is to use a slow shutter speed. You can then pick up the existing light of lamps or, during the day, some of the outdoor light seeping into the room.

You can shoot at 1/15th of a second, or even a supported 1/8th that still synchronizes with your flash. What the slower shutter speed will do is allow other lights to register and give areas of warmth to the scene. Q: I have a problem that may be of interest to many of your readers now during the energy crunch: I would like to photograph my house with infrared film to find my heat leaks. I have seen pictures like this in magazines, but can find no good source of information on the methods and equipment used . A: Normally, infrared photography both in black-and-white and color is used to dramatize outdoor daylight scenes by increasing the contrast or changing the color. The filter used with black-and-white is a Kodak Wratten filter No. 87, which is a deep red. Other filters in the red-to-orange band can also be used, but with less effect. A Kodak No. 15 and a No. 21 are most effective for color but other filters in the red-orange-yellow range can be used for different effects.

Your question has to do not with ordinary infrared photography but with thermography, which uses sophisticated opto-electronic imaging equipment with infrared detectors.

Thermal infrared radiation does not expose photographic materials, but the electronic results can be photographed with conventional films.