This may seem to be a dumb question to more seasonaned LF veterans, but as a relative new comer I am perplexed about the cost of wide angle lenses. It seens that as you go wider, i.e from 75mm to 65 mm the costs actually drops. I would naturally assume it would be the other way around. I am in the market now for a lens in this size range and need to know if there is a specific reason for the price drop; such as quality concerns. I am talking same manufacturer and lens line just different focal length. Any feedback would be most appreciated.

Thanks, Rick

-- Rick Zimmer (absolutz@bellsouth.net), October 29, 2001

Answers

You are probably looking at a 75mm that will cover 4x5 with some movements and a 65mm that will only cover 2x3 and is unusable for 4x5.

-- Bob Finley (Rfinbob@aol.com), October 29, 2001.

Actually, it is pretty standard in 65mm wide angle lenses that the image circle produced is 170mm across. This compares to about 160mm for the diagonal width of a sheet of 4x5 film, so a 65mm wide angle lens would cover 4x5, but with no movements to speak of. You still have a good question there about the lower price. Maybe less glass. I don't know.

-- Don Welch (donwelch@hotmail.com), October 29, 2001.

In LF, along a given line of lenses with the same angle of coverage, the shorter lenses are just a scaled down version of the longer lenses. They cost less just because there are less materials. This cannot be the case with SLR lenses (35mm and MF) because of the mirror box which require elaborated designs. The scaling down in LF has also a limit, which is that at one point the image circle becomes too small. Then you need to switch to a more complex design with a larger angle of coverage. This switch isn't usually necessary between 75 and 65mm.

-- Q.-Tuan Luong (qtl@ai.sri.com), October 29, 2001.