Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
01-23-2011, 12:35 PM   #1
New Member
1banger's Avatar

Join Date: Jan 2011
Location: USA
Posts: 11
K-5 Sync limits.

Ok, so I have figured out that the when using remote triggers, it this case the PCB Sybersync's system, the K-5 will not send a fire signal to the hot shoe if your shutter speed is set to anything over 1/165sec.

This is usable of course, but it would be nice if the K-5 would send a fire signal
to the hot shoe in M mode, no matter what your shutter speed, and let the shooter sort out any shutter lag issues themselves.

I have a 5DMKII and it will send a fire signal up to 1/250sec.
This speed difference lets me blow out more of the ambient light
than a shutter speed of 1/165sec.

Do you think this could be fixed in a firmware update?

01-23-2011, 02:39 PM   #2
Pentaxian
RonHendriks1966's Avatar

Join Date: Jan 2009
Photos: Gallery
Posts: 8,642
Well 1/180 sec is the fastest speed on my K-5.

We have to wait. It is rumored that with upcoming new flashes 1/250 sec would be the new limit. Just wait and see if this is true in the coming months.
01-23-2011, 02:41 PM   #3
Pentaxian
philbaum's Avatar

Join Date: Oct 2007
Location: Port Townsend, Washington State, USA
Posts: 3,659
I don't have a K5, but i tested my K20 and it fires the remote on up to 1/180.

So then i tried to fire the remote in HSS at a higher shutter speed using the pop up flash, only to find that i couldn't put the remote in HSS (i didn't realize that, perhaps i'm doing that wrong)

Then i put my Metz 48 back on the hot shoe, put it in HSS and fired for practice at 1/1000.
01-23-2011, 02:44 PM   #4
Pentaxian
RonHendriks1966's Avatar

Join Date: Jan 2009
Photos: Gallery
Posts: 8,642
Yes hotshoe-connected flash can do HSS, but not as off-camera device.

01-23-2011, 02:54 PM   #5
Veteran Member
jolepp's Avatar

Join Date: Oct 2010
Location: Finland
Photos: Albums
Posts: 3,196
AFAIK the problem is that with shorter times than 1/180s the shutter is not fully open and hence the whole frame is not exposed for the whole duration of the exposure: you'd get a dark band in the picture as the flash would only light up a part of the frame.
01-23-2011, 03:16 PM   #6
Forum Member
Bobe416's Avatar

Join Date: Mar 2009
Location: Toronto
Photos: Gallery | Albums
Posts: 57
QuoteOriginally posted by 1banger Quote
Ok, so I have figured out that the when using remote triggers, it this case the PCB Sybersync's system, the K-5 will not send a fire signal to the hot shoe if your shutter speed is set to anything over 1/165sec.

This is usable of course, but it would be nice if the K-5 would send a fire signal
to the hot shoe in M mode, no matter what your shutter speed, and let the shooter sort out any shutter lag issues themselves.

I have a 5DMKII and it will send a fire signal up to 1/250sec.
This speed difference lets me blow out more of the ambient light
than a shutter speed of 1/165sec.

Do you think this could be fixed in a firmware update?
You should be getting a shutter speed of 1/180sec - make sure you are using flash X sync mode, this is the red "X" on the Mode Dial
01-23-2011, 05:18 PM   #7
Pentaxian
Wheatfield's Avatar

Join Date: Apr 2008
Location: The wheatfields of Canada
Posts: 10,055
The K5 sync speed is 1/180th. If you are not syncing that fast with your sybersyncs, they are the problem, not the camera.
My K5 syncs perfectly at 1/180th with my Pocket Wizards.
1/250th would be nice, but it is a mere half stop faster than the present speed (IE, not enough to get worked up over), and for Pentax to get that sort of sync speed with their flash units, I expect they would need to be redesigned as well.

I recall reading over on either Photonet ot Luminous Landscape that people were getting underexposure problems with Canon flash units at 1/250th because the burn duration can be longer than the sync speed.
01-23-2011, 05:20 PM   #8
Veteran Member
MrPetkus's Avatar

Join Date: Feb 2010
Location: Long Island, NY
Posts: 388
Go to menu page C1 on the camera and change "EV Steps" to "1/2 EV Steps" instead of "1/3 EV Steps".

You don't need to use the red "X" setting to use 1/180 shutter. That's just there so that you won't accidentally change shutter values when using flash units that don't automatically set sync speed.

The K5 has a max sync speed of 1/180 - not the fastest out there. You can use values less than but not greater than 1/180.

01-24-2011, 06:38 AM   #9
Veteran Member
sterretje's Avatar

Join Date: Dec 2008
Location: Roodepoort, South Africa
Photos: Gallery | Albums
Posts: 3,534
Flash sync speed is basically a physical limitation. It's the fastest shutterspeed at which the camera has both curtains of the shutter open so the full film/sensor is exposed when the flash fires.

Now it's possible that this is actually faster on Pentax cameras and Pentax for some reason has decided to use 1/180 instead of 1/250 or 1/500 or whatever in which case a firmware update might 'fix' it. However why would Pentax not use that shutter speed as the X-sync if it is feasable from a hardware perspective?

One (probably the only) reason I can think of is that the duration of the built-in flash at max power is 1/180s (I could not find that spec); this again is a hardware limitation. But I don't consider this likely; I'm sure Pentax either would have improved the built-in flash or that they would have put a system in place that would use 1/180s in combination with the built-in flash and a X-sync better than 1/180 with an external flash if that would have given them a better spec for the X-sync.

So in my opinion, forget about a firmware update to allow a X-sync faster than 1/180s.
01-24-2011, 07:32 AM   #10
New Member
1banger's Avatar

Join Date: Jan 2011
Location: USA
Posts: 11
Original Poster
1/180 is fine for most situations. Just wish that Pentax would try to use a more standard syn speed of 1/250, like the rest of the industry. This would allow us to freeze some action shots like water splashing and such.

I can freeze water drops and splashes with my Canon at 1/250. 1/180 is close, but you can see the difference in the shots.

I'm just trying to replace "all" my Canon and Nikon gear with Pentax, and it seems that they are determined to not let me do it! K-5 won't even tether without a 3rd party software, that solution can be very finicky, and I still need that support to be in Lightroom.
01-24-2011, 07:57 AM   #11
Pentaxian
RonHendriks1966's Avatar

Join Date: Jan 2009
Photos: Gallery
Posts: 8,642
QuoteOriginally posted by 1banger Quote
1/180 is fine for most situations. Just wish that Pentax would try to use a more standard syn speed of 1/250, like the rest of the industry.
Well there was rescently a discussion about that, but 1/250 isn't as standard as you may think.
01-24-2011, 04:42 PM   #12
Pentaxian
Digitalis's Avatar

Join Date: Mar 2009
Location: Adelaide.
Posts: 8,611
QuoteOriginally posted by 1banger Quote
Just wish that Pentax would try to use a more standard synch speed of 1/250, like the rest of the industry
The 1/250th synch speed is not a "standard" in any sense of the word. Camera manufacturers have always done whatever they feel like when it comes to the design and manufacture of their shutter mechanisms. In bright daylight the difference between 1/250th and 1/180th is trivial. The DR of the sensor is greater than the difference between 1/250th and 1/180th so stop complaining.

Pentax 645D -1/125th FP synch speed - the Pentax 645 and 645NII had a 1/60th synch speed - and these were highly regarded cameras by professionals.
Pentax 67II - Widely used for professional portraiture and it only had a synch speed of 1/30th
Leica M3 to M7 had a synch speed of 1/50th - the Konica Hexar RF the main competitor to the Leica M7 had a synch speed of 1/125th. Only the M8 and M9 have a 1/250th synch speed, but who the hell uses flash with a leica?
Pentax spotmatic ( and many other camera from this era) only had synch speeds of 1/60th

I did this list off the top of my head,I'm sure there are plenty of other cameras out there with below "standard" synch speeds. I will point out the pentax medium format cameras did have leaf shutter lenses made for them, which brought the synch speed to 1/500th.

Last edited by Digitalis; 01-24-2011 at 04:50 PM.
01-24-2011, 11:45 PM   #13
Veteran Member
Zebooka's Avatar

Join Date: May 2008
Location: Russia, Siberia, Novosibirsk
Posts: 323
Btw.

360 FGZ flash can do 1/1000 in A mode when mounted on my LX5.
It can do something like 1/640 when mounted via cable.
And it can do 1/320 when triggered using Yongnuo RF-602 radio triggers (canon version) mounted on LX5.
01-25-2011, 01:05 AM   #14
Pentaxian
Digitalis's Avatar

Join Date: Mar 2009
Location: Adelaide.
Posts: 8,611
QuoteOriginally posted by Zebooka Quote
Btw.

360 FGZ flash can do 1/1000 in A mode when mounted on my LX5.
It can do something like 1/640 when mounted via cable.
And it can do 1/320 when triggered using Yongnuo RF-602 radio triggers (canon version) mounted on LX5.
Interesting, with my LX5 and my Elinchrom triggers I can get 1/1300th with my studio strobes, with no apparent reduction in reliability.

The reason why the LX5 has such high synch speeds is that it is using a leaf shutter, albeit as small one, and the smaller the shutter the less mass that has to move = faster synch speeds. That is why they are using exotic materials such as titanium, carbon fibre and kevlar in the construction of camera shutters - like the shutter in my nikon D3s.
01-25-2011, 02:52 AM   #15
Veteran Member
Zebooka's Avatar

Join Date: May 2008
Location: Russia, Siberia, Novosibirsk
Posts: 323
QuoteOriginally posted by Digitalis Quote
The reason why the LX5 has such high synch speeds is that it is using a leaf shutter, albeit as small one, and the smaller the shutter the less mass that has to move = faster synch speeds. That is why they are using exotic materials such as titanium, carbon fibre and kevlar in the construction of camera shutters - like the shutter in my nikon D3s.
I know that.
This was one of the reasons why I bought LX5, not s95 (no hot-shoe).

But I was reffering to the fact that Pentax flashes can sync at speeds higher than 1/180.
Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
camera, dslr, fire, k-5, k-5 ii, k-5 iis, k5, pentax k-5, shoe, shutter
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Term limits jeffkrol General Talk 7 11-17-2010 01:31 PM
Marketplace off limits? TourDeForce Site Suggestions and Help 10 07-31-2009 07:24 PM
Theoretical limits... frith Troubleshooting and Beginner Help 3 06-03-2009 06:33 AM
Post Attachment Limits David Site Suggestions and Help 2 12-05-2007 12:28 PM



All times are GMT -7. The time now is 12:03 AM. | See also: NikonForums.com, CanonForums.com part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top