[ArneTorp]

I am wondering what flash I should invest in when I buy my K-3. I see that Pentax, Metz and Sigma has different models that are quite similar in specs. The Pentax is WR but has a lower guide number than the Sigma but is the Sigma working 100% with the P-TTL and wireless?

So which should I buy?

[elliott]

I am wondering what flash I should invest in when I buy my K-3. I see that Pentax, Metz and Sigma has different models that are quite similar in specs. The Pentax is WR but has a lower guide number than the Sigma but is the Sigma working 100% with the P-TTL and wireless?

So which should I buy?

Regarding the guide number, the Sigma 610, Pentax 540 and Metz 58 are similar at similar zoom levels, the Sigma and Metz can just zoom further. At 85mm the Pentax is rated at 54m, the Sigma is 56m and the Metz is 52m. The Metz and Sigma can zoom to 105mm, which is where they get their guide numbers of 58m and 61m.

Here is a chart showing the guide numbers for P-TTL compatible flashes.
http://pttl.mattdm.org/power:guide-numbers

[ArneTorp]

That I didn't know - so they are not that different in guide number.

But the Sigma EF-610 DG Super costs under half of what the Pentax does here in Norway - Almost a third (Pentax AF-540FGZ $547, Sigma EF-610 DG Super $200) Is the Pentax flash better in the way it performs on a Pentax camera that it's worth the big difference in price? Is there anything the Pentax does that the Sigma does not on a K-3 (Or a K10D for that matter)

[jake14mw]

I think that's a crazy price for the new Pentax. Can you find an older model 540? They should be much less. From the new model the main things you would be missing would be WR, LED light for video, and the smaller size.

[jake14mw]

That site that elliot gave you has all kinds of information about comparing the functionality of the different flashes.

[ArneTorp]

I have now been looking at the site and can't find anything there to justify buying the Pentax over the Sigma except for WR, size and LED for video as jake14mw stated. For me those are not important.

So if nothing big happens with the Pentax price, I guess it will be sigma then - Thanks!

[elliott]

Don't rule out the Metz 58 AF-2, it is a very nice flash with a lot more features than the Sigma.

[ArneTorp]

The Metz 58 AF-2 is sold for $450 - are the features it offers worth the difference?

[elliott]

That is up to you, the non-TTL auto modes are very nice to have for use with non-A and adapted M42 lenses (and in situations where P-TTL gets confused), the Sigma doesn't have that.

[ArneTorp]

Can they all be used as slaves - Like if I buy two - can I use them at the same time on a stand?

[snostorm]

Pentax branded P-TTL flashes have at least one advantage over the 3rd party flashes -- If the Pentax DSLR body designers upgrade features or protocols for P-TTL or wireless remote TTL in the bodies, these changes are made to be compatible with the firmware built into their own flashes, but not necessarily the 3rd party flashes. Many of the latter allow user firmware updates via a USB port, but others don't. . The bottom line of this is that used 3rd party "P-TTL compatible flashes" might actually not be completely compatible with newer Pentax models as they are released, and could possibly not be upgradable to the newest current protocols or to new developments that might appear in the future. So far, the original 360 FGZ and 540 FGZ models have remained 100% compatible through a number of changes in flash protocols since the first DSLR bodies, the *ist D and DS.

I haven't checked recently, but there might be one other advantage -- both the 360 and 540 Pentax flashes in the FGZ series (both old and new models) can be used as wireless remote TTL slaves using the popup flash as a master or controller (with camera bodies that allow this -- almost all of the DSLRS) while (IIRC) only a few of the top models of 3rd party flashes will allow remote wireless TTL metered flash triggered/controlled by the popup. The others require that you use another external P-TTL flash on-camera as the master or controller, so you might actually need to buy another flash unit in order to use this feature. What will work with what in wireless TTL mode is a very confusing aspect of external flash, and is probably best explained in detail on this page:

Wireless - Pentax P-TTL Flash Comparison

Bottom line, all external flash units are not equal, even though the spec sheets might look very similar. Is the price differential justifiable? -- that's a potential user's decision, but I remember that a lot of early 3rd party P-TTL external flash users were very disappointed when their units no longer worked when they upgraded the body in their Pentax system, and they had to send their unit in to the factory for rechipping, or were told that updating the unit might no longer be supported in their discontinued model. The USB ports in some of the newer models would rectify this only if the mfg follows through with updated firmware as needed in a timely fashion. As far as wireless TTL goes, it's actually hard to decide if this might be a feature that is important if you've never used it, but I have found it to be very useful. . . YMMV, but I would not dismiss it lightly.

BTW, I've owned and used original 360 and 540 FGZs for over 7 years with a progression of bodies, the DS, K100DS, K10, K20, K-7, K-5, K-5IIs, and will get a K-3 sometime before spring.

One more thing -- flash power is not nearly as important as it was with film. The ability to use much higher ISO with little degradation of IQ can easily overcome even significant-seeming differences in max power (GN) from an external flash.

Scott

[ArneTorp]

As I can see on the comparison page I see that the Sigma should be compatible as of now.

Sigma's Super versions can act as both slave or controller; the ST versions can't do either. Be aware that in low light when using a built-in flash as a controller, a EF-530 DG Super slave may be triggered erroneously by the autofocus assist strobe used on camera bodies without a dedicated focus-assist light. Pentax and Metz flashes don't have this problem, and it's a non-issue on newer camera bodies which have a focus-assist lamp. (Not sure yet about the updated Sigma model.)

And as I can read the Metz has some issues in HSS

The 58 AF-1 and AF-2 can do both, but due to a bug in the current firmware, neither model can do HSS in master/controller mode. (They work fine as HSS slaves, if a Pentax flash is the controller.) There are currently no known plans for an updated firmware to fix this issue.

I know that third party isn't always updated at the same time, but for me it's only important that it will work with K10 and K-3. Has anybody tried the K-3 with the Pentax and the Sigma yet?

[Lucky-Luc]

I own a Metz 58 AF-2 and the K3, and I am very happy with it.

[elliott]

One more thing -- flash power is not nearly as important as it was with film. The ability to use much higher ISO with little degradation of IQ can easily overcome even significant-seeming differences in max power (GN) from an external flash.

It is still just as important, light modifiers still eat light, bouncing still eats light. If you intend to use HSS in bright situations then you need quite a bit of power, since the strobing for HSS reduces the actual output a lot.

For simple and direct flash, yeah, you don't need much power. I get by fine with my "lightweight" setup of a K100D, Sunpak 144D (20m @ 35mm) and a small prime. Bouncing on any ceiling over 8ft is pretty much out of the question though.

[snostorm]

It is still just as important, light modifiers still eat light, bouncing still eats light. If you intend to use HSS in bright situations then you need quite a bit of power, since the strobing for HSS reduces the actual output a lot.

For simple and direct flash, yeah, you don't need much power. I get by fine with my "lightweight" setup of a K100D, Sunpak 144D (20m @ 35mm) and a small prime. Bouncing on any ceiling over 8ft is pretty much out of the question though.

This is a very valid point, but I was thinking mainly about bodies with the last few generations of Sony Exmor sensors (Kx and newer, K-5 and newer). I should have been more specific. . . but I did say "much higher ISO with little degradation of IQ". With the earlier CCD and CMOS sensors, flash power requirements were not much different from film.

Scott