[JimD]

Back in the dark ages I was ok with flash on my MX's. Guide Numbers, even on occasions battery packs hanging from my shoulder, small Nissin and Sunpack units, etc. But as for flash on dslr. Not a clue.

I've had my K5 (first dslr) for just about a year and except for some initial messing around with the pop-up unit I haven't had the need or inclination. However a couple of months ago I had a bit of spare cash and bought a Metz AF50, which seemed to have some decent reviews.

Is there somewhere where a complete novice/idiot can get some basic info on what, why, where and how digital flash and slrs (K5) do? The Metz handbook is not easy to follow. Particularly as I don't fully understand what is the difference between M, TTL, P-TTL, P-TTLHSS and so on actually is or does.


The K5 manual isn't the most explanatory book I've ever read. Looking up some topics I begin to loose the will to live. For instance why on the X setting, does the EV bar keep flashing -5 ?

As I said. I'm a complete idiot when it comes to digital flash.............Anyone got any bulbs?

[Adam]

Regarding the X issue- the camera is saying that it thinks the photo will be underexposed if you shoot with the current settings.

As far as modes go:
M is for manual, where the flash fires at the configured power setting and you have to manually ensure that the iso, shutter speed, and aperture are correct.

TTL is where the camera uses its own sensor once the correct exposure is reached. Only the istD and DS/DS2 have this sensor.

P-TTL is where the camera calculates what the flash intensity should be, and then fires at that setting w/o making any further measurements. Like TTL, this gives you full automation, but it only works if the camera knows the lens's aperture setting. This means that you have to use manual flash mode with manual lenses on modern Pentax DSLRs.

HSS stands for high speed sync, which lets you use shutter speeds up to 1/500.

All in all, if you don't have any manual lenses, you'll probably just want to leave your flash in P-TTL mode and let the camera do the thinking

[JimD]

Thanks Adam. That's a start.

What about fill in and bouned flash with this set up. Is it just trial and error or are these things a bit more sophisticated?

I do have a half dozen or so SMC's from another life but I think I can handle that

[steve1307]

Bounced flash in P-TTL with appropriate lenses works the same method as if the flash was in normal postion.
It pre flashes measures and adjusts the main output accordingly. Bounced flash aimed at a ceiling will use more power output or it wont carry as far but the AF540 has enough power to fill a decent sized room with a normal height white ceiling.

Of course with the older manual lenses you just have to know (or guess) how much power to use in M mode.


Edit: Sorry. Metz 50, a bit less power than the Pentax AF540 but more than the AF360.

In the 1 week i've had the Metz 50 I've found that the P-TTL is a bit more accurate exposure than the Pentax. (mind you i've got a special focus screen fitted that messes with my metering a bit, so i often have to dial in some EV+ or FEC+ on slower lenses.). YMMV

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Last edited by steve1307; 07-23-2012 at 03:40 AM.

[top-quark]

Hi Jim,

I recently went through all the various shooting modes on the K-5 to show how they interact with P-TTL flash. Also did a bit with HSS. I hope you find it useful:
https://www.pentaxforums.com/forums/pentax-k-5/191116-some-insight-into-flash...ml#post2020805

[JimD]

Thanks very much guys.

[steve1307]

Hi Jim,

I recently went through all the various shooting modes on the K-5 to show how they interact with P-TTL flash. Also did a bit with HSS. I hope you find it useful:
https://www.pentaxforums.com/forums/pentax-k-5/191116-some-insight-into-flash...ml#post2020805

+1 for you on the post in the the other thread. very helpful