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The purpose of the HELP! column is to provide solutions to photographic problems, to find sources of supply and to identify cameras. HELP! is not a pricing or appraisal service, and cannot provide values for old equipment. There are several good guide books available from our advertisers which give prices. Thanks for your cooperation!

Q. I have a 25' roll of Kodachrome double 8mm film, No. 369, develop before date of Sept. 1953. As far as I can tell the film may have been exposed, but has not been developed. The reason for believing so is that I opened the can in a dark bag and found the film to still be double and the factory paper wrapping was missing. The can had been opened because the tape was awry. I am assuming that a double film would have been split if processed. According to my local photo supplier, Kodak no longer processes 8mm film nor could they give me a processor, local or elsewhere--except they did mention a Rocky Mountain Film which I have been unable to locate. Can you supply a developers name? Thanks in advance.
Thomas DeMan
Akron, OH

A. Your assumption that the film would be split after processing is correct. The raw unprocessed 25' long film was on a small metal spool about 13/4 to 2" in diameter and about 16mm wide with perforations along both sides. After processing, the film was split and returned on a plastic projector reel about 3" in diameter and the film was now 8mm wide, 50' long, with perforations on one side only. I don't know of any method to determine if the film is still raw (unexposed) or exposed. As I remember there was a paper tape that held the raw film tightly wound on the reel which normally was discarded after it was exposed. But I have not used any of this film for 30 years even though I still have several 8mm cameras. I called Kodak's customer hotline at (800) 242-2424 and they told me that Rocky Mountain Film is the only lab still processing this process K-11 pre-1960 Kodachrome film. However, they can only process it in black and white, not color as was the normal end result. If you want to find out if they can do this, contact the lab at 560 Geneva St., Aurora, CO 80010; (303) 364-6444. I would also check on the cost and time needed as with many older, long discontinued processes, it can be prohibitively expensive since there is little demand or volume.
Robert E. Mayer

Q. I am looking for a certain Nikor developing tank. This tank was, to the best of my knowledge, used in the 1960s and 1970s. It could process 21/4x31/4 up to 4x5 sheet film. I used this tank while in the Air Force. The tank was stainless steel and could be adjusted to the film being used. When the Air Force decided to do away with sheet film these tanks were stored. Maybe one of your readers have or know where one is and could let me know. Thanks.
Carl W. Reed
RR 3 Box 420
Pine Grove, PA 17963

A. I know the Nikor stainless steel tank system very well as I still have and use two sizes of tanks and spiral reels holding either two or four 35mm (or one or two 120) films. I know they also offered many other sizes from small, short 16mm rolls up to huge open top models for processing 100' rolls of 70mm film that we used for black and white portrait negatives at a university photo service I managed in the 1960s. I personally don't remember the multipurpose model for sheet film, but I'm sure they had one as they seemed to have most other sizes available in that era. We will print your complete address so any reader having one of these sheet film tank/reel units can contact you directly. I hope one or more of the readers will have one and will contact you. If you are interested in current adjustable-size equipment for processing sheet films, Jobo offers one for use in their rotary processors. You can call (800) 627-5511 to obtain product literature or write Jobo Fototechnic, Inc., PO Box 3721, Ann Arbor, MI 48106.
Robert E. Mayer

Q. First, I would like a copy of the manual you have for the Canonet QL17. I have three of them that I'm going to give to my grandkids. Second, could you explain a simple but complicated (to me) lighting system. I get confused with the following: Joules, Watt Seconds, Guide Numbers. What is the common denominator? What equals what? Keep up the good work!
Angelo C. Iovinelli
Silverdale, WA

A. Thanks for the kind words about our efforts to answer reader inquiries. We do try, even though some of them take quite a while because they require considerable research. A copy of the requested instructions for the Canonet QL17 is being sent in your SASE. I agree, there is considerable confusion about the terms used to measure electronic flash output. Fortunately I had just received a review copy of a new book titled The Photographic Flash, A Concise Illustrated History by Bron and Condax. They provide a pretty good description of the terms, which I quote. "Manufac-turers and photographers need meaningful measures of the light-producing power of electronic flash units. The engineers who design the devices naturally think in terms of electrical energy, watt-seconds. Another name for the watt-second quantity is the joule, honoring the English physicist, J.P. Joule, in recognition of his pioneering work in electricity and the mechanical equivalence of heat. As a measurement joules, though, are not directly usable in determining photographic exposure, and are thus only a rough guide for a photographer in comparing the relative power of flash units. But even two flash units with the same rating in joules may not have the same photographic effect, due to different efficiencies in converting electrical energy into light, or to different types of reflectors or enclosures. Guide numbers are another attempt at practical power rating, but even these are not totally reliable. Practical tests under working conditions or measurement with an accurate strobe meter are always recommended." Even the experts are confused and misled by these terms, so don't feel you are alone. Each term is a rough measurement used for a starting point. I realize this does not really clarify your question, but it's better than what I could provide myself.
Robert E. Mayer

Q. I have accumulated three old cameras recently as gifts, so how can I determine whether they are of any value to a collector? 1. Rolleiflex TLR No. 667966; 2. Zeiss Nettar 120 film, Novar-Anastigmat lens, Vario 1:6.3 f/105mm; 3. Balda Dubilette pocket folding camera, 35mm film; No. 3804662 Meyer Gorlitz 1:2.9 f=5cm lens. How can I arrange to offer them for sale if they are? I appreciate your expertise regarding these questions, as I cannot find data of this type locally at all. Thanks for your valued assistance.
John Lippert
Green Valley, AZ

A. First of all, we would need more information about the Rolleiflex TLR as there were so many different models offered from 1929 until the current models. For instance there were Zeiss Tessar; Zeiss Xenar; Zeiss Planar, and Zeiss Xenotar lenses. Some were 75mm f/3.5 and others were 80mm f/2.8. I believe there were also models of the camera. At least my Rolleicord (a less featured, more manual operation model) was offered in several models such as my VI model, which I purchased new in 1955 while in college. The serial number should help, but I don't have any list breaking down the serial number/year of production. The Zeiss Nettar was made from 1934-1941 and again from 1949-1957. My 1996 12th edition Blue Book called it an inexpensive folding roll film camera and showed a price of $35. Unfortunately I could not find the particular 35mm Balda model you have in any of a half-dozen price guides I looked at. I trust this will assist you a bit. You could advertise them for sale in Shutterbug, but I would suggest first checking the wanted columns for TLR, medium format (for the 120), and 35mm for a few months to see if anybody is looking for the particular model(s) you have. That's the method I use when trying to sell older equipment.
Robert E. Mayer

Q. I'd appreciate some tips on exposure length estimates for night shots using a tripod. The shots would be of things like city lights, display windows, that sort of thing.
Rick Derevan
via Internet

A. Most internal camera meters, even the segmented types on today's sophisticated AF SLR cameras, tend to read the pinpoints of light in a typical nighttime situation plus all of the darkness surrounding the lights, then average the exposure. But, since the large dark areas are more prevalent than the tiny lights, the results are often unsatisfactory exposures.
There are many published low-light exposure guides that I have found to be very accurate. Most guides consist of a dial and a list of various typical night subjects. Once you put in your ISO film speed it will give suggested exposure times. They get you in the ballpark for the correct exposure, but I suggest bracketing your exposures beyond what the guide suggests, giving twice and four times as much exposure as was recommended by the guide. Kodak Master Photoguides had these guides. So does the Harris Xisting Light guide. The 1991 Harris I have shows a list price of $11.95 postpaid which might not be correct today. Contact Harris Photoguides, 83 Rock Beach Rd., Rochester, NY 14617 for current pricing. There are other guides such as the Black Cat guide. Better photo dealers may have one or more guides in stock.
Robert E. Mayer

Q. Could I obtain from you any information on the repair of older cameras? Specifically a Pentax I Q Zoom 60 camera serial No. 7588867? Also, how can I obtain a copy of Shutterbug? Thank you very much.
Mary F. Grigsby
St. Joseph, TN

A. I called Pentax customer service in Denver and found that they do not have any parts available for this compact camera which was discontinued in 1991. They said one service that does have some parts for this model is Peachtree Camera and Video in Marietta, Georgia (770) 795-8020. Give them a call and explain what's wrong with your camera then send it for an estimate on the repair cost if they can do what's needed to repair it. If your local newsstand does not carry Shutterbug, check with a local photo dealer or bookstore. One of these businesses should carry our publication.
Robert E. Mayer

Q. What are the numbers to the right of the "A" on the aperture ring of a Canonet QL17 for? Does it have something to do with the flash?
George C. Hupp, Jr.
Ottawa, IL

A. The red "A" has a dual purpose. When set on "A," the camera's built-in electric eye metering will control the lens aperture--if you have the right mercury No. 625 battery installed. But, they are difficult to find today. You can always use it on full manual with an external meter or by estimating exposure.
You guessed correctly, the red "A" on the aperture ring is also used when the small, exclusive Canolite D flash is placed on the camera's hot shoe. Now automatic circuitry will select the proper f/stop to correspond with the distance the camera has been manually focused for. In this camera's era, the early 1970s, this was about as automatic a flash operation as was available. The three blue numbers on this same ring (28, 20, and 14) are the metric GN for semiautomatic flash operation when using then readily available flash bulbs. If you have an electronic flash unit with a GN of 92 (28), 65 (20), or 45 (14), you could set the ring to one of these numbers to have a similar automatic operation so you only have to focus and shoot.
We get lots of inquiries about this camera which has been one of my favorite compact cameras because it has a very fast lens speed (f/1.7) for low-light work plus automatic or manual control of the aperture while you control the wide range of shutter speeds coupled with an accurate rangefinder focusing system. I have had several since it was first introduced in 1970.
Robert E. Mayer

Q. I am looking for a No. 29 IR filter 37mm for a Sony HI8MM can you help me? Thanks.
Charles R. Tinsley
via Internet

A. I have found a good general source for filters to be The Camera People. This firm deals in new and used photo equipment specializing in new and used filters, stepping rings, adapter rings, and similar accessories. They carry many brands of filters including Tiffen, Hoya, and B+W. The items are available via mail order with a shipping and handling charge in the U.S.A. of only $4.50. Their address is 64 W Mill St., PO Box 1069, Bayfield, CO 81122. For information, call (970) 884-6045. They have a catalog listing items available. You can order by calling (800) 382-2644. Hopefully they will have the specialized filter you seek or can guide you to a source.
Robert E. Mayer

Q. J. A. Babcock asked if there was an adapter to fit his Nikon 200mm f/4 IF macro lens to his Canon EOS 1N camera. I purchased an adapter from B&H Camera which allows me to use all of the manual focus lenses for my Nikon FM on my Canon Elan IIe. All of these lenses will focus to infinity. Of course the lenses and the camera must be operated in the manual mode. As an example, I have a Vivitar 19mm lens and a Tokina 28-70mm zoom lens for my Nikon FM that work quite well with my Canon camera.
Vic Allebach
Newport News, VA

A. Thanks for providing this helpful and enlightening data. Truthfully I was not aware any adapter existed that would adapt Nikon lenses to a Canon EOS mount, let alone still allow them to also be capable of focusing to infinity with his Nikkor 200/4 IF macro lens on an EOS camera body. We also heard from Henry Posner of B&H Photo who said, "Such adapters do exist. The unit for Nikon AI lenses to EOS bodies retails here for $39.95. While Mr. Mayer correctly states that extending a lens from a body normally prevents infinity focus, these adapters include a single element designed specifically to overcome this optical problem." Thanks for this additional data Henry. It is understandable the lens with an adapter would have to be used in manual mode, but that would be a minor inconvenience in my estimation. We appreciate both of these people sending in this data to assist reader Babcock and I'm sure many others who may want to use one brand of lens mount with another entirely different camera system.
Robert E. Mayer

Q. I am a college photographer working with liquid photo emulsion but cannot figure out the proper developing times to produce a useable image or to even keep an image outside the darkroom. I read the article you featured in Shutterbug many months ago but it did not help. Is there anyone I could contact for specific chemical and time use?
Michael Thompson
via Internet

A. If the liquid emulsion you have is the brand called Liquid Light, the firm's current address is: Rockland Colloid Corp., PO Box 376, Piermont, NY 10968; (914) 359-5559; web site at: Hopefully they should be able to answer your questions about this product.
Robert E. Mayer