Originally posted by ckeene ...the problem is happening with the XPro-P being turned on but the AD-200 is powered off. my workflow starts with a bracketed series of 5 (ambient only) images. no flash involved.
The XPro-P emulates a flash to the camera, so that might be a key. I don't own an XPro-P, but was able to try your case for a couple of scenarios using stuff I do own. Basic set-up was: P mode, 5-point bracket, fixed ISO (200) each exposure done singly with flash ready.
- Pentax AF280T flash (analog dedication/TTL protocol) in auto-thyristor mode : Able to replicate (same camera settings for all five exposures) with flash firing for all five. EC indicated on review, but not done. Flash ready indicated in viewfinder. Flash EC icon lit in viewfinder
- Pentax AF280T flash (analog protocol) in M mode :Bracketing done through camera settings as expected with flash firing on all five. Flash ready not indicated in viewfinder. Flash EC icon not lit in viewfinder
- Sigma EF-610 DG Super (digital protocol) in P-TTL mode : Bracketing accomplished through flash EC with camera settings remaining the same for all five
- Sigma EF-610 DG Super (digital protocol) in M mode : Bracketing done through camera settings with flash firing for all five. Flash ready indicated in viewfinder. Flash EC icon not lit in viewfinder
The important cases are numbers one and two with the Pentax flash. The cases with the Sigma flash were as expected. Note that for case one, the camera is set to do flash EC on a flash that does not support that feature, with the result that the shutter speed and aperture were held constant for all bracket points.
The reason why I tested against the AF280T flash is because the K-3 and other Pentax dSLRs offer partial support for the analog flash dedication protocol as signaled through the "ready", and "mode" contacts only. Information signaled includes: "flash ready", "flash mode", "exposure good", and "use this aperture"; in response the K-3 may limit shutter speed to X-sync or below, display flash ready or exposure good, and may also set aperture according to the flash's suggestion. How exactly this translates on the K-3 depends on exposure mode and the mode selected on the flash. See my review on the AF280T if wanting to know more
LINK.
The short story is that I believe that the XPro-P may be doing at least partial Pentax analog protocol emulation such that
the camera detects a flash that it "thinks" it can send flash EC directives to. Such would be a corner-case bug in the XPro-P emulation of fairly minor importance.
Steve