Pentax dedicated flash on Canon T3.

vision1961 wrote:

Lemming51 wrote:

vision1961 wrote:

Henry's rental stock is fully booked out for the time I needed to rent a Canon Speedlite flash to sit on my Canon T3 for a couple of days.

Instead I have been offered the loan of Pentax dedicated flash (for a KX1 camera) which apparently worked well with a Canon T3i a couple of years ago, just wondering if anyone has any insight on compatability or any settings that may need adjusting?

If it's got a non-TTL auto mode, a la old auto-thyrister speedlites, then it'll work in Av and M modes so long as you coordinate ISO and aperture settings.

Otherwise, Pentax TTL/P-TTL is very different from Canon's ETTL and you will not have auto TTL flash exposure. It'll just fire at full power (only the large center triggering pin in the hotshoe is common to most systems).

I am a pretty much a novice with my T3 and have only used it so far in Full Auto mode. I have been asked however if I would like to be the second shooter at a wedding next weekend

Not trying to sound too harsh, just realistic.  Given your apparent lack of camera skills, you have a lot to learn about flash photography, and little time to learn.

I was going to mention the thyristor flash as well.  But with thyristor you're not going to succeed in full auto mode, you'll need to gauge distance and set f-stops/ISO manually on the flash and on the camera.

If your only option with the Pentax flash is full power mode, or some manual power setting mode (1/4, 1/2, full, etc.), don't even bother.  Flash power falls off quickly with distance, so what looks good at one distance will be under/over-exposed just a few feet away.  You'll just get frustrated trying to guess at the power setting unless you have a staged setting where the distance to your subject is fixed.

Given what we know at this point, I'd say your best bet is to use your pop-up flash as best you can, because at least that will work with your full auto shooting style.