For presentations in (horizontal mode) as ratio of screen to front row < 2 × screen height and screen to last row < 8 × screen height. (Kodak publication S-102 Audiovisual Slide Projection)
End view of plug:
Agfa Scalla - a black and white reversal film which can be processed for black and white slides.
Kodak Technical Pan is a good choice for copying black and white negatives for use as slides.
Kodak T-Max 100 can be processed directly for black and white slides using the T-Max 100 Direct Positive Film Developing Kit.
For white text on black background titles or other very high contrast line art consider Kodak Ektagraphic HC slide. Ektagraphic HC slide is a very slow(EI 25 or lower depending on developer) orthochromatic reversal film. It can even be processed under safelight.
Based on info from Kodak publications S-80-2 AV Equipment Memo and S-102 Audiovisual Slide Projection maximum light output is achieved with 4" to 7" fixed focal length f:2.8 lens. Zoom lens of equivalent focal lengths will result in lower light output. Kodak reports apetures larger than f:2.5 do not greatly increase output.
Kodak publications index can provide many helpful documents. We found publication S-74 The Source Book - Kodak Ektagraphic Slide Projectors to be especially useful. As of late 1999 many of the documents were not available online but could be ordered for a nominal charge.