AREA NEWS

HINTS AND TIPS Patrick Marchment. Spencer (Area 22). Here are a few more hints and tips from member Patrick Marchment and the first are concerned with projector care:-

Avoid switching the projector on and off frequently. Leave it switched on until the show is finished to extend lamp life. Avoid moving or jogging the projector as a hot filament is much more susceptible to damage than a cold one. If a projector needs to be tilted limit the tilt to 10 degrees. It is far better to lower the screen or to raise the overall height of the projector. Always purchase lamps of the correct voltage. Whereas domestic lamps are suitable in the range of 220/250 volts, projector lamps are designed for operating on 220/230 or 240/250 volts. Do not fit lamps of higher wattage then the projector is designed to accept. Serious overheating could cause irrepairable damage. Shop around for bargains when buying new lamps and always keep a spare handy as they always blow at the most inconvenient times.

FLASHY COPIES. As is well known, copying slides with ordinary film results in increased contrast. Here is a way of reducing contrast with ordinary film. It is more convenient if the camera is fitted with a multi exposure facility although there are ways of managing without.

First make a normal exposure with the slide in the copier. Then replace the slide with a 2.0 neutral density filter and repeat the exposure on the same frame at the same speed and aperture as before. Use a Kodak Wratten 2.0 filter which has a 2.0 log value. (not a 2x filter of some other brand which gives only one stop reduction). The 2.0 log value gives a reduction of 6.5 stops and thereby flashes the film for 1/00 of the first exposure. This technique has been found to work well with Fuji 100 ASA film but should work well with other brands. Incidentally, the unexposed part of a processed Ektachrome 100 ASA professional film is reported to have a factor of 100x or 6.5 stops so it might be worth trying the leader from other brands of film. Please let us know if you have tried this out.

FOR PRINT FANS Peter Guy (Area 20) I have been involved in quite a lot of printing recently, in the preparation for a City & Guild photography exam, and there are two items of printing aids that I would not be without.

The first is the KODAK COLOUR VIEWING KIT, which comes in a pack of six sets of colour filter cards and which may be used for slides or for colour negatives. The prints must be viewed in daylight or colour corrected artificial light and filters are used as follows:-

Say you have a print properly exposed, but showing a slight yellow cast. You view the print with a colour filter that is opposite to the cast, in this case a blue filter. By holding the filter a couple of feet from the print, then quickly flicking the filter in and out of the line of vision, you can observe the colour correction the filter makes. If 10 units is not enough try 20, or an inbetween unit could be the one to use.The other item is a printing exposure calculator, and is only obtainable from "Club Durst". This is a 6" diameter plastic disc, with a moveable 4" diameter inner disc and a moveable cursor. On one side are printed exposure times with three primary colours. On the other side there is a white light printing guide and a solution temperature calculator. On the very outside ring there is a colour-ring-round calculator. The exposure calculator works as follows:-

Take a slide print that shows a slight yellow cast on which the exposure was correct. Say it was 20 seconds with a 40 yellow and 20 magenta. The Kodak Filter Kit told me that 10 units of yellow removed would correct the cast but how much of a change of exposure would be needed? The calculator tells me exactly. By putting the cursor to the exposure time of 20 seconds with all the zeros of the colours in line with it, the inner disc is moved until the 10 units of yellow mark is in line with it, the inner disc is moved until the 10 units of yellow mark is in line with the cursor. The cursor is moved until it is in line with the zero yellow and this reads the new exposure which is 17.5 seconds. It really is a great little gadget, and I think that it takes a lot longer to write about than to actually use it.

KODAK R-25 COLOUR PRINT VIEWING KIT cat. no. 150075 appx. £6.79.

CLUB DURST EXPOSURE CALCULATOR: Club Durst, P.O. Box 14, Altrincham, Cheshire, WA14 2PP. Tel. 061-928-2073. Appx. £13.00.