Originally posted by GeneV Opinions vary. Is it not useful just because you say so?
I think it goes without saying that I just expressed my viewpoint and did not imply that everyone needs to adopt it.
I believe using the built-in flash to contribute to the illumination of the subject almost always results in results that are not consistent with using a DSLR of this category. In other words, the respective (lack of) sophistication of the image can be had with much simpler means.
The use of the built-in flash as a trigger for external flashes is a different matter, but even then you end up with the possibility of seeing its weak output during the main flash and have to arrange your external flashes in a way that they can "see" the on-camera flash.
Originally posted by GeneV I use the flash in this way often, and so do many others.
That's fine, but perhaps you wouldn't use the built-in flash anymore if you tried the alternative of having a dedicated flash controller like the V6 on top of the camera.
It is so much easier to be able to place external flashes any way you want them without caring for line-of-sight, and being able to define different flash power output levels (i.e., lighting ratios) by just turning a dial on an on-camera V6.
Originally posted by GeneV If there were a radio control, then I'd be up for that, but otherwise the body needs a control mechanism, and the only one we have for Pentax is the optical control.
You can use the Cactus V6 (or similar systems from Godox or Radiopopper) with radio control for Pentax today.
Flash power level control is manual, but P-TTL does not really support multiple off-camera flashes anyhow, so anyone using more than one off-camera flash has very little to lose and a lot to gain by switching from optical P-TTL to radio-based triggering.