K20D sync speed... 1/100s

CapitaineAbitibi · 04-21-2008, 05:01 AM

Hello everyone!

Well yesterday I tested my K20D in a studio shoot and I found out a BIG issue with the camera, the one thing I deleted all the test pictures without really thinking about it, but the sync speed of the K20D is not 1/180s on X mode. At 1/180 you can still see the shutter at the bottom of the frame and it gives an awful shadow... I had to go down to 1/100s to get a clear shutter free picture.

My K10D was working perfectly at 1/180... hopefully they will fix this with a firmware upgrade... or maybe once again I got a defective pentax product. If it's the case I'm switching to Nikon... IF only you knew all the issues I had with my Pentax material, I could write a novel I think.

ftpaddict · 04-21-2008, 05:04 AM

That's odd. My K100D syncs at 1/180 without any issues. Did you use an external flash? Have you tried with more than one unit?

Hopefully a firmware update would fix this issue.

CapitaineAbitibi · 04-21-2008, 05:15 AM

Originally Posted by ftpaddict

That's odd. My K100D syncs at 1/180 without any issues. Did you use an external flash? Have you tried with more than one unit?

Hopefully a firmware update would fix this issue.

I know... my K10D was syncing at 1/180 without any issues, my *ist DS at 1/160 (if I remember correctly).

I had three different flash units with me, and I tried both with a sync cable and wireless trigger... it was a bit better with the cable, I could go at 1/125, but above that limit nothing was good.

Lowell Goudge · 04-21-2008, 05:47 AM

Originally Posted by CapitaineAbitibi

I know... my K10D was syncing at 1/180 without any issues, my *ist DS at 1/160 (if I remember correctly).

I had three different flash units with me, and I tried both with a sync cable and wireless trigger... it was a bit better with the cable, I could go at 1/125, but above that limit nothing was good.

what flash units did you use? some flash units have durations at full power that exceed the full open time of the shutters.

There was a discussion thread about this a while back. I tried to get this time from pentax, but they wouold not give it.

roscot · 04-21-2008, 06:02 AM

Were you using radio slaves, like Pocket Wizards? I am never able to sync above 1/125 with the K10D. Some of the cheap ebay radio slaves are even worse. Hot shoe flash syncs fine at 1/180.

jshurak · 04-21-2008, 06:29 AM

Originally Posted by roscot

Were you using radio slaves, like Pocket Wizards? I am never able to sync above 1/125 with the K10D. Some of the cheap ebay radio slaves are even worse. Hot shoe flash syncs fine at 1/180.

Are you getting that sync speed with pocket wizards?

stewart_photo · 04-21-2008, 06:33 AM

Originally Posted by CapitaineAbitibi

(snip) Well yesterday I tested my K20D in a studio shoot (snip) I had to go down to 1/100s to get a clear shutter free picture. (snip) My K10D was working perfectly at 1/180... (snip)

Actually, this has been widely discussed in many venues. It's even been mention at least once in Shutterbug magazine (in regards to the K10D). The X-sync speed listed in the manual of the K10D and later cameras is wrong in many instances. With a studio strobe, most will not see speeds greater than 1/100 second, though a few have reported 1/125 second. In other words, you'll likely only see the 1/180 second with a portable flash mounted on the camera hotshoe or used wirelessly. Having said that, it's not really a big issue since most studio strobes are designed to work best at 1/100 second. Since there is no great advantage to shooting with faster speeds in the studio (been doing it for months), simply set your camera for 1/100 second and take your pictures.

stewart

Lowell Goudge · 04-21-2008, 07:51 AM

As an additional note, I believe the shutter is the same in the K10D and K20D, therefore the results should be the same.

As stewart has mentioned, and also as I pointed out, many strobes have longer durations than the full frame open time of the shutter and therefore will give the results you describe.

CapitaineAbitibi · 04-21-2008, 10:13 AM

Originally Posted by jshurak

Are you getting that sync speed with pocket wizards?

I don't remember the brand of the radio trigger

But I tried the sync connector of the camera body and I got 1/125 instead of 1/100...

A friend of mine was helping me during the shoot, he has a D200 and he was able to sync at 1/250, so I don't think it's a flash issue.

I do remember though, my K10D (previous camera) couldn't trigger some flash units even with a hot shot adaptor.

and · 04-21-2008, 10:41 AM

I sync at 1/180 with pocket wizards with no problems. with k10d.
but there are several sources of error
some radio triggers are unable to sync at 1/180, like some cheap chinese ones
some flashes have flash durations at certain power levels that is slower than 1/180 so they cannot be synced that fast, the metz af58 comes to mind.

mauricio · 04-22-2008, 06:37 AM

I have been using a couple of K10D extensively in my studio at 1/180 with no problems.

roscot · 04-22-2008, 06:57 AM

If you use a sync cord with studio flashes, you can sync at 1/180. The issue is when using the radio slaves.

Lowell Goudge · 04-22-2008, 09:41 AM

this might be a really dumb question but are the flashes you are using P-TTL compatible, or are they firing on the first preflash and then not properly synchronized with the shutter?

mauricio · 04-22-2008, 11:23 AM

I'm using radio transmitters. In my case I'm using Elinchrom Skyports with 5 flash heads

My 2 K20D will arrive next week and then I'll be able to try it out...but like I said, no problem with the K10D's

MRRiley · 04-22-2008, 11:57 AM

I've been to 2 shoots where the studio owner provided Pocket Wizards and Alien Bee strobes. No problems at all syncing at 1/180 with my K10D...