Archived posting to the Leica Users Group, 1999/01/19
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Bob, Even a minute variation of shutter speed or lens aperture will change exposure and, through exposure, the perception of hues. There is a lot of room for 'slight' variations there, every camera having its own shutter speed calibration profile (and each speed possibly deviating differently from the calibrated speed). Same for diaphragm management. All of this together can bring variations of around 1/3 EV (sometimes more judging from shutter speed graphs published here and there). Enough to explain what may be perceived as a colour shift. Colour transmission tests are made for certain lens tests: some conclude to a slightly 'warm' rendition, some to a slightly 'cold' rendition, but these variations from 'neutral' are not repeatable through product ranges. Examples from CdI (not the bible but on my lap): Minolta AF 35-105: very slightly green dominance; Minolta AF 35-105 (new version): very slightly warm dominance; Minolta AF 35-70 f4: neutral; Leica Apo-Telyt-R 180mm f3.4: slightly warm; Leica Apo-Elmarit-R 180mm f2.8: neutral; Micro-Nikkor 60mm AF: slightly warm; Micro-Nikkor AF 105mm f2.8: neutral; Carl Zeiss Sonnar 85mm f2.8: slightly warm; etc, etc, etc.... This converges with my own personal experience, which does not include ANY personal testing, only usage. The subjective impressions given in this thread vary. I have seen posts elsewhere arguing that Contax is too warm, others arguing that Contax is evidently cooler, etc, etc. My Contax shots: some are 'warm', some are 'cool', depends on the light, on the exposure settings and on the film. Voilą. Alan FIGLIO4CAP@aol.com wrote: > > In a message dated 1/19/99 2:34:41 AM Eastern Standard Time, AlanBall@csi.com > writes: > > << one needs lab conditions to compare colour rendition of > lenses. >> > I don't think so - only if you need to quantify the spectral transmission. It > seems to me that if you set up a tripod, shoot a series of photos with a body > and lens, rewind the film, advance the film in the "other" body and lens > combination and shoot a series of the identical subject, that any observed > color differences can be attributed to differences in the two camera systems. > I did this and did see the color casts which I reported here. > > Bob Figlio