Originally posted by Rayn Can it trigger multiple flashes using Wireless HSS P-TTL (and if so, how to do it)
The flash system on the K-3 is supposed to be the same as the K-30. According to the manual, it can do HSS with multiple Pentax flashes using wireless P-TTL, but not with the built in flash, so you need to take a Pentax P-TTL external flash and mount it on the camera's hot shoe in order to trigger other flashes. The manual for my Metz doesn't mention anything other than HSS with a single flash. From the standpoint of the flash units, HSS is achieved by firing the flash for a shorter duration, which limits the light output. All the faster shutter speed does is reduce the amount of ambient light in the exposure. In situations with low ambient light there are ways to get around HSS limitations, by manually controlling the light output of your flashes. I only have experience using HSS with a single flash.
Originally posted by Rayn What on camera control does one have of wireless/radio off-camera flash units; exposure,ratio, etc...?
You can adjust flash exposure compensation - 2 stops to +1 stop. That's it.
P-TTL has several limitations including single zone metering (and that zone covers the entire frame). Highly reflective surfaces anywhere in the frame will mess with the exposure. Contrast control sync is limited to 1/3 and 2/3 contributions from on camera and off camera flashes, and you can't change the way the camera decides to adjust flash output. For candid shots, P-TTL is better than trying to calculate flash settings in your head, but if you can control the environment and take a few test shots first, I recommend going 100% manual.
---------- Post added 11-27-14 at 10:17 PM ----------
Originally posted by Rayn someone once telling me about a 3rd party plugin for the K-3 LR tethering
There was a beta version out for a while, I have no idea if it is still under development, but the version I tried could change camera settings until you triggered the shutter, then everything crashed. With the K-3/K-5 you can use the HDMI output to monitor Live View, but that's not integrated with LR and is only a one-way tether, no matter how you look at it. So Flu-card or forget it.