JensRoesner.com   photography, engineering, tomfoolery

Pentax *ist K100D Infrared Sensitivity

pictures courtesy of Jan and Neil!
Camera: Pentax K100D
Filter: none
Exposure Time: 1/1000 sec
Aperture: 5.6
ISO: 200
EV: 13.9366
Camera: Pentax K100D
Filter: Hoya R72
Exposure time: 1/6 sec
Aperture: 5.6
ISO: 200
EV: 6.5558EV
The Pentax K100D continues the tradition of Pentax dSLRs being sensitive to IR light. Add to that the on-body shake reduction, gaining you about two stops, it is one of the best unmodded cameras available for IR today. However, sensitivity is mainly in the red channel. The other channels are so insensitive that you can pretty much forget colour IR work unless you shoot RAW for IR work. Jan also shows us what can be done with the SilkyPix RAW converter and Auto-Level. This can similarly be done in other RAW converters by changing exposure and white balance. IR is only fun with RAW ;)
Converting to greyscale and then doing autolevels in SilkyPix is very close to what you'd get from a manual adjustment.
Thanks again to Jan for providing these sample shots. Please visit his pbase gallery and the original shots for this evaluation.
Neil sent in the following JPEGs from his K100D, thanks!
Camera: Pentax K100D
Filter: none
Exposure time: 1/4000
F-stop: 4.0
ISO speed: 1600
Exposure mode: Manual
White balance: Auto
Exposure bias: 0.0000
EV: 11.9658

comment: Probably the shutter speed maxxed out. I assume usual Pentax exposure would have been a stop less.
Camera: Pentax K100D
Filter: Hoya R72
Exposure time: 1/15
F-stop: 4.0
ISO speed: 1600
Exposure mode: Manual
White balance: Auto
Orientation: Top-left
Exposure bias: 0.0000
EV: 3.9069EVEV


camera overview

copyright 2006..07 by JensRoesner.com