[GoldenWreckedAngle]

I've been leaving my K10D flash in rear curtain sync mode lately so it's already there when I need it for a blurred action shot. I shot an outdoor event recently and could not get my camera to shoot faster than 1/90 in manual mode when I had my Sigma EF530DG flash turned on. Turn off the flash and I could go as high as I wanted but the second I turn on the flash my shutter speed dropped to 1/90. It took me a while to figure out that this is the max sync speed with rear curtain sync. Ugh!

I'm just about done with my K10D's flash limitations... seriously, last straw here.

I want 1/250 sync
I want my flash to fire even when I exceed the sync speed
I want to be able to leave my flash set to rear curtain without loosing even more shutter speed

Pentax, please, make me a camera that takes flash photography seriously. Thank you.

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Last edited by GoldenWreckedAngle; 07-07-2009 at 05:06 PM.

[and]

seconded.
Pentax, I am sure it is possible to improve flash sync after 6 years of dslrs with no improvement since the first model.

strange to put a dedicated X sync mode and a pc sync port on the camera when the flash options have not improved. With live view and taking shots without the mirror flipping down it doesnt seem technically impossible to put an electronic shutter and get 1/1000 sync, seems like a great spec opportunity ripe for the taking

[Lowell Goudge]

the reason that with rear curtain sync you are limited to 1/90 is because there needs to be time while the shutter is full open, for flash exposure. flash duration is about equal to the full open time of the K10D on leading curtain sync, therefore if you want trailing curtain sync, you need to have an equivelent amount of time following the onset of the flash, before the curtain actually starts to move, so that the curtain movement does not caus un-even illumination on the image captured.

1/250 sync will only marginally improve this. to get upwards of 1/180 rear curtain sync, you need a couple of things, first of all the flash duration needs to be much shorter, and second, you will need a shutter that would offer about 1/500 sync on front curtain, the only shutter I know of that does that on a "normal" film camera is an irus shutter built into the lens itself (on view cameras etc).

for flash firing when you exceed sync you will get an un-even lit band the width of the shutter slit at the speed selected. Note that shutter speeds higher than sync speed do NOT expose the entire sensor at the same period, but use a moving window to traverse the sensor. the higher the speed the narrower the window, but the actual speed of movement of the curtain remains the same for all shots.


Have you considered high speed sync, with multiple bursts?

[drerka]

I think one of the problems the OP may be running in to, is the flash being used. If i remember correctly, the Standard version does not support high sync speed flashes. I can use my Sigma 530 Super without any problems at any speed, using the high speed sync feature.

[GoldenWreckedAngle]

the reason that with rear curtain sync you are limited to 1/90 is because there needs to be time while the shutter is full open, for flash exposure. flash duration is about equal to the full open time of the K10D on leading curtain sync, therefore if you want trailing curtain sync, you need to have an equivelent amount of time following the onset of the flash, before the curtain actually starts to move, so that the curtain movement does not caus un-even illumination on the image captured.

1/250 sync will only marginally improve this. to get upwards of 1/180 rear curtain sync, you need a couple of things, first of all the flash duration needs to be much shorter, and second, you will need a shutter that would offer about 1/500 sync on front curtain, the only shutter I know of that does that on a "normal" film camera is an irus shutter built into the lens itself (on view cameras etc).

for flash firing when you exceed sync you will get an un-even lit band the width of the shutter slit at the speed selected. Note that shutter speeds higher than sync speed do NOT expose the entire sensor at the same period, but use a moving window to traverse the sensor. the higher the speed the narrower the window, but the actual speed of movement of the curtain remains the same for all shots.


Have you considered high speed sync, with multiple bursts?

Got all that but I have my reasons for wanting to cheat the sync (ala David Ziser style.)

As to HSS, not here. Not in this situation. Let me set this up a little better before I leave myself open to the usual, "you just think you need that but you really don't" comments I typically get when I express my thoughts about Pentax's considerable flash limitations.

I rarely need rear curtain sync at speeds faster than 1/90; I doubt many people do. I'm sure I could make up a hypothetical situation where it might be helpful but that is not the problem in this case. I just don't want to constantly have to change it. I want to set it in rear curtain and leave it alone.

Here's the scenario. I was shooting a child's birthday party with a water slide and lots of high speed games in mid-day sun. Every shot needs fill flash to keep the highlight to shadow ratio looking good. I'm creating a mix of stop action and blurred motion shots and I don't want to take my eye out of the viewfinder and dink with something while a shot gets away.

I set my flash to rear curtain and ttl, because sometimes I need it and sometimes I don't but, hey why mess with it right? I then dial in my exposure at F5.6 and forget about it. When I want motion blur I roll the front dial left three or four clicks and the rear dial right the same number while I'm tracking my subject. When I want stop action I roll them back. Check a few shots and histograms every few minutes and keep rolling.

Dang, why are all of my stop action shots over exposing? fiddle fiddle fiddle. Bang, I'm hitting a 1/90 wall on my shutter speed and I can't get it to go to max sync to save my life... Reboot flash, reboot camera, separate the two and put it all back together, etc.. Finally figure out that I'm stuck at 1/90 for rear curtain sync., as far as I can tell, an undocumented "feature."

Pentax! Arrrrrgh! Some of us use our flash you know! The least they could do would be to have the flash mode automatically switch to regular flash above 1/90.

It's just one more flash related irritation on a list that keeps growing with my experience. It seems that every time I learn something new with my flash I hit another Pentax wall; One more thing I have to live with that my Nikon and Canon shooting buddies don't. It's just a lot of little stuff that's adding up to enough already ya know.

Sorry for the drama - Just needed to get this off my chest. All better now... until next time.

[GoldenWreckedAngle]

I think one of the problems the OP may be running in to, is the flash being used. If i remember correctly, the Standard version does not support high sync speed flashes. I can use my Sigma 530 Super without any problems at any speed, using the high speed sync feature.

Sorry, I left off the "Super" part but we are shooting the same flash and it's not the problem. HSS is not the answer. A series of reduced power flicks of light are not going to help much with mid-day action shots.

[Lowell Goudge]

Got all that but I have my reasons for wanting to cheat the sync (ala David Ziser style.)

As to HSS, not here. Not in this situation. Let me set this up a little better before I leave myself open to the usual, "you just think you need that but you really don't" comments I typically get when I express my thoughts about Pentax's considerable flash limitations.

I rarely need rear curtain sync at speeds faster than 1/90; I doubt many people do. I'm sure I could make up a hypothetical situation where it might be helpful but that is not the problem in this case. I just don't want to constantly have to change it. I want to set it in rear curtain and leave it alone.

Here's the scenario. I was shooting a child's birthday party with a water slide and lots of high speed games in mid-day sun. Every shot needs fill flash to keep the highlight to shadow ratio looking good. I'm creating a mix of stop action and blurred motion shots and I don't want to take my eye out of the viewfinder and dink with something while a shot gets away.

I set my flash to ttl, because sometimes I need it and sometimes I don't but, hey why mess with it right? I then dial in my exposure at F5.6 and forget about it. When I want motion blur I roll the front dial left three or four clicks and the rear dial right the same number while I'm tracking my subject. When I want stop action I roll them back. Check a few shots and histograms every few minutes and keep rolling.

Dang, why are all of my stop action shots over exposing? fiddle fiddle fiddle. Bang, I'm hitting a 1/90 wall on my shutter speed and I can't get it to go to max sync to save my life... Reboot flash, reboot camera, separate the two and put it all back together, etc.. Finally figure out that I'm stuck at 1/90 for rear curtain sync., as far as I can tell, an undocumented "feature."

Pentax! Arrrrrgh! Some of us use our flash you know! The least they could do would be to have the flash mode automatically switch to regular flash above 1/90.

It's just one more flash related irritation on a list that keeps growing with my experience. It seems that every time I learn something new with my flash I hit another Pentax wall; One more thing I have to live with that my Nikon and Canon shooting buddies don't. It's just a lot of little stuff that's adding up to enough already ya know.

Sorry for the drama - Just needed to get this off my chest. All better now... until next time.

so why not add either a neutral density filter,?

I see what you are getting at, and you want, for the blurred shots to have the flash go off at the end of the blurr, etc, but if you want to continuously switch back and forth between stop action where the flash does most of it, and a blurr shot where the exposure is more ballanced, I don't see how you will achieve this.

Even with 1/250 (like the new K7, or my old PZ-1) you will not have 1/250 and rear sync. In fact I doubt any one does, so there is no need to go pentax bashing here for a feature that no one has.

at best you can ask for the removal of flash and shutter speed lock out, but your shots, with only part of the frame exposed will simply look like s#!t. with a dark band somewhere due to the under exposed portion.

You also need to consider the flash itself, in terms of reliability and pulse energy through the flash tube. a much faster flash but with the same guide number will be very bright and put a lot of power though the bulb. I don't know where the trade off between life and energy is, but you certainly might be pushing it.

[GoldenWreckedAngle]

... to get upwards of 1/180 rear curtain sync, you need a couple of things, first of all the flash duration needs to be much shorter, and second, you will need a shutter that would offer about 1/500 sync on front curtain, the only shutter I know of that does that on a "normal" film camera is an irus shutter built into the lens itself (on view cameras etc)...

The 50D and a the D300 both fire their flash in rear curtain sync at their regular front curtain sync speed and you can freely exceed that speed and still get an uneven flash exposure if you want to, and by George, I want to . I don't know if they just auto switch to front curtain above a certain speed or what but the flash fires and nobody has to access a menu and change a setting to make it happen.

I've read on the blogs of several of the top professionals in both brands that they recommend setting the flash to rear curtain and leaving it there. Not a recommendation I can follow as a Pentax shooter.

[GoldenWreckedAngle]

No offense but I could have predicted most of the responses I've gotten so far:

1) You need to learn about High Speed Sync... check. (mid-day sun, action, nuff-said)

2) Neutral density filter... check. (have them, love them, but they will not solve a shutter limitation, only an aperture limitation, which this is not)

3) Nobody else can do it... check. (but to nit pick, yes, they can)

4) This is not really a problem, it's actually a feature that helps keep you from making crappy pictures... check. (thanks, I'm sure I need all the help I can get because if I was a real photographer I wouldn't be shooting Pentax right?) Touche' . Here's an example of the type of crappy shot you can make above the sync speed with a Canon but not with a Pentax.

5) It's not the camera, it's your other brand accessory... check. (Nope)

6) It's not the camera, it's you... check. (Sometimes, too often really, but not today)

6) Pentax basher... check. (I bashed my head on the wall a few times first, does that earn me any rant points?)

To be fair, I'm writing with a little more energy than this latest discovery probably deserves but to be equally fair it's one of several flash related limitations that should have been addressed with the K-7. As far as I can tell, Pentax is just not addressing the flash photographer's wish list (maybe, nobody is sending them flash photographer wish lists). I'm hoping that maybe, just maybe this thread will be the one that makes the pile of ... uh... flash related complaints big enough that Pentax will finally spare an engineer or two to catch up a bit in this area.

Of course I shoot a K10D. I'm two models away from current myself - Just another straw. Am I the only straw? Boy, wouldn't that be embarrassing... Thank Google for anonymous internet names hu?

[GoldenWreckedAngle]

Even with 1/250 (like the new K7...

Make that 1/180, and that right there is the nerve ...

K-7 = K20D + (long wait x speculative hype) + lots of catch-up features, including video + 8 bit HDR jpegs + shrinky dink treatment - basic flash improvements I've been waiting for since the K10D. The list just grew by one more discovery.

I want the K-7 cool-aide; I like the K-7 cool-aide; but I just can't drink the K-7 cool-aide until they sweeten the flash features, because everyone else's flash features are already a whole lot sweeter. So here I stand with my straw, my last straw, humbly asking Pentax to keep me in mind next time. -Thanks-

[cwood]

Make that 1/180, and that right there is the nerve ...

K-7 = K20D + (long wait x speculative hype) + lots of catch-up features, including video + 8 bit HDR jpegs + shrinky dink treatment - basic flash improvements I've been waiting for since the K10D. The list just grew by one more discovery.

I want the K-7 cool-aide; I like the K-7 cool-aide; but I just can't drink the K-7 cool-aide until they sweeten the flash features, because everyone else's flash features are already a whole lot sweeter. So here I stand with my straw, my last straw, humbly asking Pentax to keep me in mind next time. -Thanks-

you seem a tad jumpy so before you go accusing me of excessive brand loyalty or anything just take what i'm saying as nothing more than either facts or presumed facts with no intent to convince you to stay with Pentax.

A Pentax employee was posting here for a while to clear the air on some things regarding k-7. Here is his response to questions about the shutter and sync speed.
https://www.pentaxforums.com/forums/613677-post51.html

Again this is not a brand apology - but I can understand this hurdle for a small company like Pentax. Canon does not design new shutters for $500 cameras, they design them for $5000 cameras and the technology trickles down. Pentax obviously has to decide where to invest their money and they decided that few enough people would care about x-sync speed that they would put their money somewhere else. It is unfortunate that it causes you so much frustration.

Personally I am continuously frustrated with all flash systems including the 580exII on my 1DmkIII. Again this is not an excuse. It frustrates me for different reasons. Off the top of my head here I can't decide which system I hate more

By the way that was a beautiful bridal portrait. Care to explain your setup and lighting on that? You said it was shot above sync speed?

[GoldenWreckedAngle]

you seem a tad jumpy

LOL - Sorry, I've had more than my share of coffee and friendly jabs from a Nikon buddy of mine today.

A Pentax employee was posting here for a while to clear the air on some things regarding k-7. Here is his response to questions about the shutter and sync speed.
https://www.pentaxforums.com/forums/613677-post51.html

I participated in that thread and the last time I posted that exact link to prove that we are still stuck with the same shutter we've had since the K10D someone posted a counter link from an employee in Japan claiming the shutter had been completely redesigned. I don't know which scenario is true and I honestly can't decide which is more frustrating.

By the way that was a beautiful bridal portrait. Care to explain your setup and lighting on that? You said it was shot above sync speed?

That is a David Ziser photo shot with a Canon at 1/320. I apologize to you and David Ziser both for not making that very clear. I don't have a camera that will let me cheat the sync speed so I couldn't show you an example of my own even if I could hang with David's considerable shooting skill (working on it, and probably will be for a while). Anyway, I posted a link above to one of David's blog posts explaining the whole thing. It's a pretty slick trick.

[Digitalis]

that image you used as an example really doesn't do anything for me, the whole thing looks over processed for my liking. - each to his own.

mate I think you should consider Switching to either Nikon or canon, because there is no way you can get past the shutter speed limit on any current Pentax camera body. As you undoubtedly know, the hot shoe goes cold above 1/180th.

I do recall mentioning leaf shutter lenses to you... here is one way to implement such a lens; you could use a radio triggering system which can be synched to the PC sync port that is on the lens which is used to fire the flashes. Though I can only think of two wireless systems that are reliable up to 1/500th of a second, Pocketwizard and Elinchrom(I HAVE heard of the elinchrom pulling off 1/2000th). On Pentax cameras the leaf shutter is fired when the camera stops down the apeture. set your camera shutter to 1/8th and the leaf shutter lens will do it's thing.. .That would be the only way you could bypass the 1/180th limit.

the Pentax 645 system has a 75mm f/2.8 leaf shutter lens that would fit the bill quite niceley, though the focal length works out to be around 112.5mm.

[Arpe]

I find it difficult to believe that a flash needs 1/90s to fire to get the rear curtain look? Doesn't a flash take milliseconds?

[kittykat46]

I use Rear-Curtain Flash too.
Works for me, just to share with you how I did it.

I have few complaints about 1/90s, because if I try to shoot, e.g. 1/180s shutter, I simply won't get the "blurred" effect I want for rear-curtain, unless its very fast moving. Not with kids playing.

I set either Tv shutter priority (max out at 1/90s on Rear Curtain, of course) or Program mode, minimum ISO. The camera will not overexpose, because it will adjust the aperture accordingly. In broad daylight I might end up with f/16 or f/22. No big deal.
I set -1 E/V Flash compensation, which is the usual technique for fill flash.

I live in the Tropics - a few rare times, at midday, 1/90s f/22 ISO200 still overexposes. I gave up on those occasions, but I won't trash Pentax just because of that. If its very important to me I'll buy an ND filter