K110D and Three Older Pentax Flashes

Hi All,

Coming to grips with my K110D - loving it so far!

The pop-up flash works a treat in all modes, and I have a little AF200Sa which does to same. This little external flash really doesn't have much more reach than the pop-up so not worth the effort.

My AF200S and sadly, my AF280T, doen't behave at all. Seem to blast out full power no matter what.

I was hoping the AF280T would work TTL or even Auto thyristor, as it has a longer reach than the pop-up, and can be swivel/tilted.
Seems no matter what I do, I get completely blown-out images, unless I'm really far away or AV my f stops way down - pure hit and miss.

The K110D manual only covers the pop-up and AF360FGZ, AF540FGZ external units. Fair ball. Just leaves me wondering why the little AF200Sa (Program) unit works so well.

I'm sure I'm missing something?

Or it's time for a 540FGZ?

Mac,
The only dSLRs that support TTL are the *ist-D and *ist-DS. No other.

However, you can use them all in "A" mode. I'm using a Metz 50MZ5 on "A" mode on the K10D and K20D with no problems.
Just a few things to keep in mind with "A" mode:
1) Fix the ISO of the camera. Auto ISO just won't work
2) Use Av mode on the camera, of course, and match it to that set on the little list on the back of the flash (but you knew that already).

My guess is you have Auto ISO enabled on the camera and, of course, the flash doesn't know about it
(It's also worth noting that the way the camera and flash tether in A mode seems to vary. The Metz will track your selected ISO and aperture all the time. Oddly the AF540 and AF360 don't track - it's all manual.)

Couple of advantages of using "A" mode:
a) you can work with dumb slaves (slave-flashes, not the servant type )
b) people who blink on the preflash don't have time to blink with a single flash in "A" mode (which is why the Metz is going into service for me!)

Hope that helps!

Matt

EDIT: Did I say I was writing a book It's turning into a monster!!

Matt,

Boy, do I need your book! And yes, that sure helps.

If you want to Beta test your book on a "Flash For Dummies" type - I'm your guy!

Thanks for the explanation and suggestions - can't wait to try them out.

Matt,

BINGO!

Thanks so much!

Don, it's a bit odd about the AF200Sa & AF200S. As far as I can tell, the "S" should be the same as the "Sa", but with the addition of a low power A mode, and M mode.

Mind you, as I mentioned, there may be other information that's passed across, and the two flashes may behave differently.

That said, you should be able to use any "A" or "M" mode flash on the Pentax. I even have a little AF160 that works just fine

Matt

Oops! Crossed in the ether

Glad I helped out
Matt

EDIT: It's likely I'll make the book available on a "beta" with no images - and then update it when the images are available to all those that have paid already

Matt,

How do we "Pay Already?"

I've gone and missed something AGAIN!

LOL! Not yet. Let me explain: It's going to take some serious time to finish the whole book. By the time the words are done, there'll be enough information to benefit the majority. At that time I'll set up a PayPal payment mechanism to buy the PDF e-book. Anyone who buys the "words-only" version will get automatically upgraded once the images are done (so you won't have to pay twice).

I've been rather ill over this week, and have only been able to think about writing more, rather than actually write anything! Hopefully I'll get back on track next week

Matt

Be well, Matt!

Here's a thought.

In my nearly two years hanging out on this forum, I've been consistently impressed, and frequently amazed at Matt's apparently inexhaustible supply of technical knowledge, and, more to the point, patience.

He carries on being prepared to answer questions helpfully and politely, long after lesser mortals such as myself start grumpily mumbling things like 'RTFM' ...

So, how about we give something back to the guy.

I'd be prepared to

a) pay Matt in advance for the book and
b) offer my services free as proofreader, or beta-tester, if you like, prior to the first 'words-only' edition.

It might be helpful for him to get feedback on the way, as it were, on readability, errata, etc.

Obviously I have a slightly vested interest in seeing the book's material early, and I wouldn't deny that I'd be pleased to have such a 'heads up'.

But it's not my primary motivation. I'd be happy to pay up front in any case, even if he doesn't want proofreaders.

To my mind, it would be a bit like paying in arrears for his outstanding contribution to date.

Thanks for the encouragement Don & Chris
Let me see how I get on in the next week or so, and then I'll PM
Matt

BTW, I completely missed Mac's beta-test suggestion above - I must have scrolled right past somehow.

Not at all my intention to steal anyone's thunder - sorry

... just two great minds thinking alike, hopefully

I'd like to add a small comment. Many of the older flash units present trigger voltages - measured at the hot shoe or PC connector - which can fry the electronics of DSLRs. I measured one of mine at over 200v. Various sources suggest that Pentax DSLRs can handle up to 30v; C**** apparently handles up to 6v. I measured my AF400T at 9v, safe enough.

http://www.botzilla.com/photo/strobeVolts.html lists trigger voltages for many flash units. If your oldie but goodie isn't listed, using a digital volt meter is the way to go. Here in the states they cost $20 and up. Just power up the flash and put one lead on the center shoe contact; the other on the contact that touches the edge of the hotshoe. With a PC connector it's one to pin, one to ring.

Now if only my AF400T would work TTL with my K10D. Why oh why did Pentax use TTL on the *stD and not on later units? The AF400T with my LX is heavenly....

Think you missed a zero
I seem to remember it was in the region of 300 to 400V for Pentax DSLRs.
EDIT: See This old thread:
One reason is that TTL flash requires another light sensor to pick up the reflected light off the film. The low pass filters on the CCD can be quite reflective apparently, compared to film which was fairly matt.
I'm not 100% sure if it's down to these technical issues, or whether it's down to having another sensor, or something else.

This weekend I'm using my old Metz in "A" mode on the K20D I'll let you know how it goes
Matt

Thanks for the correction on the safe trigger voltage. I guess I can use anything in my stable!

Re: TTL. It would seem that, if TTL works for the *stD it could work for the others. In film cameras TTL would have to accomodate varying degrees of different films' reflectivity, while with DSLRs the low pass filters would be a known quantity. Does anyone know how C**** and N**** handle their flash systems?

A cynical view might be that an added sensor would cost more, and would reduce sales of a new line of flashes. A pity that Pentax's backward compatiblity for the revered K-mount couldn't extend to flashes.