Originally posted by Class A That's exactly what Smeggy did (intentionally or not). His K20D front focuses under Tungsten light, like every other K20 but due to the backfocus bias he dialed in, the front-focusing still leaves the target within the DOF.
I suggested a similar technique (just based on oversharpening instead of embossing) in a
previous post. I think the oversharpening halos work just as well.
Looking at the K-5 shots again, I noticed there are more than one shot suggesting FF for the K-5 under low light. Not knowing how the light levels were obtained, what care was taken in focusing, etc. it is difficult to assign a lot of weight to this. Assuming that the EV values were not calibrated by looking at the actual image brightness at the AF spot, they would actually have to be lower by roughly 2 EV (due to a missing 18% gray calibration). Sure, the tests might reveal a problem, they are just not as convincing as they could have been.
I have a K5 due this week, which gives me a trifecta of: K20, K7, K5 to compare.
I also have a reasonable test setup that will allow me to check in Tungsten lighting from about EV2 to EV 10 or 11, and a pair of 5500k CFL lights for some tests in lighting that is less red.
I have a Sekonic L-358 to measure the EV level at the target and a color meter to measure the color at the target as well.
My setup is repeatible and accurate enough without going overboard and getting into real lab conditions and optical benches and so on. At the end of the day my real test is to use the camera indoors in normal lighting I encounter all the time and also outdoors in a similar fashion wherer the K20 has been ok for me for several years now.
FWIW, I also have no interest in trying and adjust for what "might" be seen by the various sensors in the camera, nor do I really care about tweaking EV readings to compensate for the lack of blue and green or whatever. I have the sort of tools that are commonly available and used in various forms of photography such as handheld meters and halogen modeling lights on my studio flashes, as well as a decent target that can be properly aligned and which also has a flat surface to focus upon.
I already know that my K20 will not hold DOF below about f4.0 in tungsten lighting at EV2. I also know that the specification for the K20 is lower than this. As I mentioned above, I have a way of calibrating the K20 to make the most of the available DOF, and in most cases I shoot bounce flash at f5.6 in this sort of light which has given me decent results with the K20. If the K5 can match this, I will be happy.
Hopefully the K5 will show up with 1.02 installed so I can run a direct 1.02 vs 1.03 comparison.
I will post some test images once the K5 arrives.
Ray