by mxdata
Sorry to hear that the special purpose Kodak B&W films that were good for this application are being dropped. This was always the preferred technique if you needed to make a high quality B&W duplicate slide.
For "casual" use, (ie:most railfan slide shows) I have found that the quickest solution is usually to make a nice 8x10 black and white print and make a duplicate slide using daylight color slide film in a 35mm camera with macro lens mounted on a copy stand. I have tried various films for this, and my favorite has been Kodachrome 64 simply because it renders an almost correct B&W color balance when exposed with "soft white" bulbs and an 80A blue filter. I have always liked this combination because it is very consistent and predictable, and soft white bulbs are readily available in most places while photofloods sometimes are not. I usually have a camera loaded with Kodachrome 64 so it is very convenient for me. The various Ektachrome films and the Fuji Velvia all seem to end up with a predominant tint in this lighting which requires adding an additional gelatin color correction filter to the standard 80A. Kodachrome is a very contrasty film so the print you copy should NOT be on a high contrast paper. If your camera has auto exposure mode, and the exposure seems to be going longer than one second, try test exposures at 2x and 4x compensation settings, as Kodachrome slows down significantly in long exposures under copy stand lighting.
For more critical use, the black and white prints can be copied using Kodak Ektachrome eDupe slide duplicating film. This is a low contrast film and will more accurately portray the full range of tones in a black and white original. However, eDupe has two disadvantages as a copy camera film. One is that it is so slow that it is below the settable exposure index on some cameras, and use of the auto exposure setting may therefore require 2x, 4x or even more compensation. The other disadvantage is that eDupe varies in color balance from lot to lot and so you have to keep adjusting your filter pack unless you buy it in bulk rolls, refrigerate it, and then make your own 24 or 36 exposure rolls as needed. Unlike the situation on a repronar where you can put the color correction filters in the lighting path, in copy camera use the filters have to go in the optical path between the camera and the copy board. This usually requires a gelatin filter holder and making some test exposures to get the color balance right. Then when you calculate your filter pack, you need to make sure that you combine filter values to get down to the absolute minimum number of filters between the lens and the board, or you will be degrading your optical performance. Buying an exact color correction filter (rather than stacking a couple of filters in smaller correction increments) costs about $30 a sheet nowadays, another disadvantage. It is a lot of trouble to go through just to make a couple nice black and white slides.
Frankly, if you can arrive at a reasonably good rendering of black and white tones by using a standard daylight color slide film in your copy camera, that is probably the best way to go. Most people in the audience aren't very likely to notice the difference between slides made this way and slides made with a high resolution, low contrast film like eDupe.
For "casual" use, (ie:most railfan slide shows) I have found that the quickest solution is usually to make a nice 8x10 black and white print and make a duplicate slide using daylight color slide film in a 35mm camera with macro lens mounted on a copy stand. I have tried various films for this, and my favorite has been Kodachrome 64 simply because it renders an almost correct B&W color balance when exposed with "soft white" bulbs and an 80A blue filter. I have always liked this combination because it is very consistent and predictable, and soft white bulbs are readily available in most places while photofloods sometimes are not. I usually have a camera loaded with Kodachrome 64 so it is very convenient for me. The various Ektachrome films and the Fuji Velvia all seem to end up with a predominant tint in this lighting which requires adding an additional gelatin color correction filter to the standard 80A. Kodachrome is a very contrasty film so the print you copy should NOT be on a high contrast paper. If your camera has auto exposure mode, and the exposure seems to be going longer than one second, try test exposures at 2x and 4x compensation settings, as Kodachrome slows down significantly in long exposures under copy stand lighting.
For more critical use, the black and white prints can be copied using Kodak Ektachrome eDupe slide duplicating film. This is a low contrast film and will more accurately portray the full range of tones in a black and white original. However, eDupe has two disadvantages as a copy camera film. One is that it is so slow that it is below the settable exposure index on some cameras, and use of the auto exposure setting may therefore require 2x, 4x or even more compensation. The other disadvantage is that eDupe varies in color balance from lot to lot and so you have to keep adjusting your filter pack unless you buy it in bulk rolls, refrigerate it, and then make your own 24 or 36 exposure rolls as needed. Unlike the situation on a repronar where you can put the color correction filters in the lighting path, in copy camera use the filters have to go in the optical path between the camera and the copy board. This usually requires a gelatin filter holder and making some test exposures to get the color balance right. Then when you calculate your filter pack, you need to make sure that you combine filter values to get down to the absolute minimum number of filters between the lens and the board, or you will be degrading your optical performance. Buying an exact color correction filter (rather than stacking a couple of filters in smaller correction increments) costs about $30 a sheet nowadays, another disadvantage. It is a lot of trouble to go through just to make a couple nice black and white slides.
Frankly, if you can arrive at a reasonably good rendering of black and white tones by using a standard daylight color slide film in your copy camera, that is probably the best way to go. Most people in the audience aren't very likely to notice the difference between slides made this way and slides made with a high resolution, low contrast film like eDupe.
