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Frequently Asked LarScan Questions

What focal length lens should I use?  What size negative do you want? A 20mm lens will give you a 360 DOV that is 4.9 inches long and will fit in a 4x5 enlarger. A 24mm lens will give you a 5.9 inch long 360DOV that can also fit in many 4x5 enlargers. A 28mm will be 6.9 inches, a 35mm will be 8.7 inches, and a 50 mm lens will give you a 12.4 inch long 360 degree field of view panorama. The choice is yours. I recomend using zoom lenses because they allow for ajustments to be made after construction is finished. For a list of focal lengths and the length of the images that they give click here.

What is the distance from the film to the lens flange? This varies from camera brand to brand.  (note: Don't make the same mistake that I did. Be sure to make the measurement with film in the body.)
Nikon = 46 .5mm
Minolta= 43mm
Olympus OM= 46mm
Konica=40.5mm
Take these values as a starting point. Confirm them by doing your own measurements.
Please measure other brands. Send values and corrections to bob@panoramic.net

How do you determine what the exposure time is? The formula is... The size of the slit in mm, times the time the camera takes to make a 360 degree turn. Divide this number by 2 times the focal length of the lens in mm times 3.14. The answer will be in the form of a fraction and is the exposure time.