COBBLER'S PAGE

By Brian Asquith (Librarian)

A recent conversation with John Batty turned round to the Xray of films. Having travelled extensively in the States, changing planes several times with his films going through seven X-Ray machines, John expressed the opinion that there was nothing to worry about. It would be interesting to know of other peoples experiences. I have read a number of tests which reached the conclusion that faster films were more prone to damage, that damage was accumulative and to be safe use a lead-lined bag. I have always used one and though I have travelled widely I have never had any film damaged to my knowledge. What does Xray damage look like? is it fogging and/or colour cast? I usually put my film cassettes into plastic slide boxes. The Kodak type take four and the longer Agfa ones take six. I must look a shady character because I never get through hand luggage checks without being asked to unpack my camera bag. It is easy to show the film through the transparent top of the container without the hassle of unpacking every box. Machines are marked "filmsafe" but one always has that feeling - are they? Can the operator turn up the power? Do they search me because of the leadlined bag? Does anyone in the club work on one of these machines and should we be worried?

I did a bit of copying the other day. I am hoping to produce an AV sequence on mountains and thought some monochrome slides might look affective. I decided to take some pictures of my collection of 20 x 16 B&W prints. It was so easy. I propped up the mounted pictures on a shelf in the bedroom, using light from the window, camera on a tripod and Konica film 1/16th of a second at F8. I processed the result in the club formula minus the chemical reversal bath (white light reversal) and got some smashing pictures with really neutral B&W. A slight increase in contrast but nothing to worry about.

When I first started serious photography years ago SLR cameras were making their mark. My first camera with interchangeable lenses was a Praktica FX2; this also had a waist level viewfinder as well as eye level. It had the standard 50mm lens, Tessar. Being interchangeable one wanted another lens, this had to be the 135mm and of course was preset ie. had to be stopped down manually before firing the shutter. All very slow but it was the F3.5 which was considered fast then. How did we manage with 15 and 25 ASA film? Along came zoom lenses which were considered inferior to "prime" lenses (fixed focal length). Now zooms are well established and are fitted as standard to a lot of modern cameras. One cannot argue about the convenience of one lens or two covering 28mm to 250mm but are we loosing out on two aspects? Zooms usually have apertures F4-F4.5. so they are not as fast as prime lenses. Quality is not as good. Distortion is apparent at the wide end of most zooms. The Tamron is faster at F1.8 and is free of distortion. The Tokina is slow at F4.5 distortion. Ideally it should be prime lenses every time and of course the experts say we should use our zooms like fixed lenses ie. set it at a certain length and move around. I zoom in and out, especially when there is little room for changing position, but when I want absolute quality I try and use fixed focal length lenses. Better still I move to a larger format. Have you ever seen 2¼" x 2¼" slides projected?

I have had a suggestion that the Library should purchase the book "Rotary Processing" by Tinsley. Unfortunately I find it is now out of print. It would be helpful to know what members consider the library should have on its shelf. We have a large collection of duplicated sheets on DIY. A lot of it is of doubtful use eg. electronic components not available, processing changed etc. Your comments would be appreciated. You may perhaps have a DIY project you could share with us.