2 Jun
2000
2 Jun
'00
7:56 a.m.
Regarding recording data on analog 35mm film, below is a recent
excerpt from a microscopy mailing list, where people were
discussing the use of film to record detail, as opposed to
CCD imaging techniques:
To begin to answer Jeremy's question directly, we
need to know
how much detail a Technical Pan negative can record. The figures
depend on processing technique and the test object luminance and
contrast, but the modulation transfer function figures published by
Kodak indicate that a spatial frequency in excess of 200 cycles per
mm is easily recordable. For a test object with contrast 100:1 they
quote 320 line pairs per mm. The CCD pixel spacing required to
achieve this feat would be 640 pixels per mm. That equates to a
requirement for 15360 x 23040 pixels to match the resolving power
of a 24x36mm Technical Pan exposure. That's 0.35 Giga pixels in
round numbers.
- John