[pentaman]

This is part 2 of my questions regarding using pTTL with K-5.

So, my understanding until yesterday was, you set your exposure for background in camera (ambient), and set the exposure for foreground in flash. And that should be it, correct?

So, I was planning to shoot in Av mode, but when I put flash in Pttl mode, the shutter speed was stuck at 1/50 no matter what aperture I chose. I thought I could simply meter in Av mode, and exposure 1 or 2 stops less using eV button.

So, when I got to the event, I pretty much had to shoot in manual mode - metering for the ambient, and choosing -0.7ev in flash. While I got some good results, I thought - what good is pTTL if I am doing things manually.

Anyone have any cheat sheet how to use pTTL in K-5?

Thanks!

[Ole]

Set the flash mode to Slow synch on the camera. That will allow the shutter speed to go below the "safe to handhold" speed.

Even then, you probably get better results with your manual approach where you control the balance between flash exposure and background!

[pentaman]

Thank you... the slow sync makes sense! Also, found this great thread, seems to answered my question:

Digital SLR and P-TTL flash guide

[pentaman]

Ok, I somehow missed the basics of Pentax TTL all this time - since I was reading Neil Van Niekerk's blog - which is written for Canon!! From what I read, Nikon and Canon implement the compensations differently.

To summarize, the EV button is a global compensation, including that for flash. And the flash EC (in the camera) controls the Flash EV only. By adjusting these two, and with any EV button on the flash, you could balance the ambient with flash. I wish Pentax made this similar to Canon.. but my fault for not recognizing this to begin with.

Thanks to all blogs/forum postings that helped me with this realization.