Archived posting to the Leica Users Group, 2007/02/18
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Hi Bob, I just ran a test, tungsten light, AWB, with and without cut filter, at all ISO settings. The photos without the filter are warm toned, have the magenta cast (even on the LowePro bag), but there was no color shift at any ISO setting. The photos with the IR cut filter are cooler in tone, no magenta cast (the LowePro bag is very black) and there is no color shift. Unfortunately I don't have a room with florescent lights so I can't duplicate your shots. I have a feeling that maybe the florescent lights don't have as much IR content which is why we don't see the magenta in your photos. Regards, Len On Feb 18, 2007, at 12:10 PM, Leonard Taupier wrote: > Hi Bob, > > Of course your questions are very valid. The photos are what they > are. I have seen a shift in the same type of scene (indoor > lighting) without changing the ISO. I feel the Auto WB may be > getting fooled at times by the high IR content in the light. I have > IR cut filters for most of my lenses now (not furnished by leica) > and I don't see the shift. Maybe I need to take more photos. Today > would be a good day with and without filters. I'll report what I > find. I'll also go up and down the ISO range. > > Magenta cast: I don't see that in your photos. The black bags look > black. I don't know what kind of material is most susceptible. I do > have a LowePro S&F Reporter 500 black bag to experiment on. The > material might be different though. > > Len >