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hi all

anyone know how to override the max flash sync speed on the D2X
it is limited to 1/250 for the sb800
but does this apply to a portable strobe light?

this i the strobe i will be using it's max flash sync speed is 1/980 second
http://www.samys.com/product.php?ItemNo=HENS7020495&tab=specs&PHPSESSID=367f4f9b3f304d6c37a2960b116ff3ab

which is handy because in afternoon light i would like to shoot faster than 1/250 to get a much darker scene with high contrast and this is not practical with a shutterspeed of of 1/250 and increasing the f stop to beyond f11

I would rather shot at 1/500 f8 but the sync speed onthe d2x only goes to 1/250

anyway around this?

I think you're under a msapprehension about synch speeds vs the speed at which your flash will go off.

The numbers quoted for the flash unit will be, for the lowest number (i.e shortest period of time) representative of the lowest light value output by the flash. As you increase the flash's power, that time period may increase, thus providing a greater amount of light for your photo, and thus requiring, for instance, a smaller aperture value.


Your synch speed is the shutter speed during which the flash trigger pulse is sent to your flash unit and your shutter is fully open at that time - ie, the first curtain has completed its travel, but the second has yet to commence its travel to close the shutter.

On the D70 the maximum synch of 1/500 can be overridden, and you're then relying the electronic shutter in the sensor to open and close (much faster than the mechanical one in front of the sensor) and the time period for the flash to be still less than, but within the boundaries set by, the flash unit.

Once you've assimilated all of that, on the D2x I would be using the same methods as used on the D70 to override the synch speed, as they're essenitally compatible with the same flash heads, and thus should be talking the same language on this regard.

Play first, and ply nicely. Expermiment, and check the results closely for evidence of any out-of-synch problems. Note where your combo's limits are, and then work within them.

Finally, why don't you just dial up the aperture and flash, which, often regardless of the availble light, should give you the results you're seeking?

thanks gary for your insight
we touched on it before last year

one reason why i don't want to increase the fstop to like f22 to get the darker exposure at 1/250 under bright afternoon sun is becauseof difraction issues i wil end up with a softer picture than one shot at f8

thus it's important for me to stay on f8 and to compensate by increasing the shutterspeed

nowon numerous occassions people have discussed the max sync speed issue on the d2x and the advantages of having a faster one

why for instance woudl the strobebe able to sync at 1/980 if no camera can sync to this speed

I may be missing something here

anyway i wil lexperiment but the hensel light is a rentel and i get it on the day i shoot

I have only used a cheaper strobe before and that had issues syncing at shuteerspeeds more than 1/250 i would get dramatic drop off in light output

thanks again

other option is just to shoot in the half hour window of last afternoon light a much darker scene
but i loose the high contrast light i like during 4:00pm light
and i know how to shoot the scene dark by using a shutterspeed of 1/500 f8

This might sound odd, but have you considered using ND filters? Same effect on brightness, albeit you now have more glass in front of the camera.

Wendell, considered using a set of ND filters? They would do exactly what you want.

Edit: LOL, considered great minds being alike?

an ND filter would decrease the brightnessof thewhole scene even the exposure on the model which i will be metering for
so that won't work

thanks anyway

wendellt wrote:one reason why i don't want to increase the fstop to like f22 to get the darker exposure at 1/250 under bright afternoon sun is becauseof difraction issues i wil end up with a softer picture than one shot at f8

thus it's important for me to stay on f8 and to compensate by increasing the shutterspeed

Sometimes it's worth trading a small amount of diffraction in order to get the result you want. It won't at some particular aperture suddenly make your pictures crap, although it is something to keep in mind.
Also, as moz mentioned the use of an ND filter has the same darkening effect as a smaller aperture, just without the DOF and diffraction issues. Obviously you would need to take into account the effect of the ND on your ambient metering (if it's TTL then it's taken care of, if it's with a hand-held meter just dial in the compensation or do the sums in your head).

why for instance woudl the strobebe able to sync at 1/980 if no camera can sync to this speed

I may be missing something here

You are. Check the ad you linked to again.
It does NOT say the flash will sync at 1/980s. It says the flash DURATION is 1/980s!
The sync speed is entirely up to your camera (as long as the flash goes off when the camera tells it to) as Gary has described.

Actually, unlike Gary's comment that the number quoted will be for the lowest power (shortest time) available, I would have assumed it was for full power. But maybe I'm used to seeing the ~1/10,000s minimum times of smaller flashes.

wendellt wrote:why for instance woudl the strobebe able to sync at 1/980 if no camera can sync to this speed

Who said that?

leaf shutters typically can synch at every speed available to them. Which usually goes to 1/500, which is wehre my Bronny synchs to. 1/500 is longer than 1/980, and thus will synch with the Bronny with no issues.

Thinking about this a little more .... 1/980 is probably the maximum output of the flash as it's quite a long (relatively) period of time. What other specs does this flash uinit have?

Other times - giving lesser light value outputs - would have shorter flash durations (1/1960 might be the 50% of max value, for instance) and thus would be less problematic. Consider whether you're going to be running the unit at max power; I rarely run mine anywhere near max.

anyway i wil lexperiment but the hensel light is a rentel and i get it on the day i shoot

I would be spending time with the unit before the shoot begins in order to get this sorted out, and to just learn its characteristics. A couple of hours, with a calibrated laptop tethered to the camera should let you get the quickest and best results.

I certainly would not be happy going on a production shoot using gear I'm not familiar with.

I have only used a cheaper strobe before and that had issues syncing at shuteerspeeds more than 1/250 i would get dramatic drop off in light output

If you're seeing a dropoff in light output, that could be the result of any of a number of issues.

For instance, the strobe may simply not be powerful enough. Unlikely to be the issue if all that you're doing is changing your shutter speed, though.

More likely will be the issue I alluded to earlier - that of the shutter synch not being aligned correctly with the duration of the flash's output. If you're using a faster shutter speed - and thus the electronic shutter - but your flash's duration extends beyond (or commences before) the period during which the shutter is open, then any light emitted by the flash during that period is just lost to your exposure.

Remember that if you're overriding the camera's synch speed then you're working beyond the working conditions for which the camera is designed and specified, and thus you're both on your own, and you also better know exactly what it is that you're doing. Fully!

other option is just to shoot in the half hour window of last afternoon light a much darker scene
but i loose the high contrast light i like during 4:00pm light
and i know how to shoot the scene dark by using a shutterspeed of 1/500 f8

What about changing the in-camera curve for a different profile?

I'm not sure that it will help, but it might be useful for a different contrast effect under less than ideal - for your needs - conditions.

DaveB wrote:Actually, unlike Gary's comment that the number quoted will be for the lowest power (shortest time) available, I would have assumed it was for full power. But maybe I'm used to seeing the ~1/10,000s minimum times of smaller flashes.

No, you're quite correct, as I noted in my subsequent post.

It's an easily made mistake. That's my story, and I'm sticking with it!

wendellt wrote:an ND filter would decrease the brightnessof thewhole scene even the exposure on the model which i will be metering for
so that won't work

True.

So dial in more flash, and increase the relative brightness of your flash-illuminated subject when compared with the rest of the scene.

hi gary

these are the specs:
# Maximum Output in Watt/Seconds: 1200 w/s
# Guide Number: F/64.2 at 2M at ISO 100, with Maxi Soft Reflector
# Recycle Time: Minimum .8 sec., Maximum 5.8 sec.
# Flash Duration: 1 Head: 1/980 second
# Flash Variability: 6 F-Stops in .1 F-Stop increments, digital control
# Voltage Stabilization: Yes, +/- 1%
# Distribution: Symmetrical
# Head Outlets: 2

I will get to test it out for a day before the shoot my mistake for saying i will just use it on the day

thanks agian for you insight

The D2X is limited to 1/250 sync speed since it has a mechanical shutter. The D70 has an electronic shutter and can effectively sync at any speed - provided you trick the camera into overriding the hard coded sync speed.

As Gary mentioned the sync speed is chosen to guarantee that the both curtains are completely open when the flash goes off (otherwise only a portion of the frame sees the light). http://en.wikipedia.org/wiki/Focal_plane_shutter has more info.

The D2X can sync at higher speeds by using High Speed sync with your SB800. High Speed sync works around this by getting the flash to output an extremely long burst of light to cover the entire time the shutter is partially open - this requires extra power and reduces the effectiveness of your flash. It also needs to be supported by your flash head.

If you need to use a larger aperture than your sync speed allows then ND filters are you best bet.

Crazy thought, there is probably another hacky solution available. You can run your flash head at full power (1/980s) and choose a shutter speed that is faster (Eg, 1/2000). A lot of light will be discardied but at least the flash will be on for the duration of the shutter. You will need to do some tests to work out which shutter speeds give you an even amount of light across the entire frame since flash output is strong at the start and decays from there. The flash duration quoted actually describes how long it takes for the light to fall off to a particular level (Eg, 50%).

wendellt wrote:an ND filter would decrease the brightnessof thewhole scene even the exposure on the model which i will be metering for
so that won't work

This is fairly easy to compensate. You can just pretend you camera has N stops less sensitivity.

xorl wrote: You can run your flash head at full power (1/980s) and choose a shutter speed that is faster (Eg, 1/2000).

Depending upon when the synch triggers, this may work with the mechanical shutter, and perhaps even at a lesser power on th flash head too.

But yes, this will require experimentation and testing to see if it really is a workable solution.

Shouldn't the D2x have FP sync with the sb800 flash enableing it to sync with any shutter speed? or are you going through the terminal on the side of the camera to fire the strobes?

xorl wrote:The D2X is limited to 1/250 sync speed since it has a mechanical shutter. The D70 has an electronic shutter

Not being a D2X owner, I've not bothered (or needed) to check if the X has the electronic shutter. If it doesn't, then this whole concept is somewhat problematic.

Michael wrote:Shouldn't the D2x have FP sync with the sb800 flash enableing it to sync with any shutter speed? or are you going through the terminal on the side of the camera to fire the strobes?

He's not using the SB800, Michael.

thanks mark that's a great idea
regarding the nd filter i would liek the expose for the foreground subject(model) and darken the background

this is the 4:00pm light



in real life it was a bright scene
I shot this at 1/500 f8 ISO100 no nd filters

now the model will be baklit so she will be dark, i want to use the strobe to illuminate her well exposed i will be using a light meter to work out exposure that creates the dark background and provides agood exposure for the model

will just have to experiment

i guess there is alot of artistic leighway in a shot liek this so even if the model is under or overexposed by a few stops it wont matter i just want to achieve a certain look, it will be very subjective

gstark wrote:Not being a D2X owner, I've not bothered (or needed) to check if the X has the electronic shutter. If it doesn't, then this whole concept is somewhat problematic.

The D2X only has a mechanical shutter. Implementing an electronic shutter requires some compromises that Nikon presumably didn't want to make. Similarly, the D200 doesn't have an electronic shutter either.

Nevermind

wendellt wrote:in real life it was a bright scene
I shot this at 1/500 f8 ISO100 no nd filters

If you add a ND2 filter you will lose 1 stop of light, hence 1/250 f8 ISO100 on camera. Set your flash meter to ISO50 and aim to get around f8 from the head. This will be a good start.

o.k my lighting guy was kind enough to do a few test shots under full midday sun

shotwith a d2h so i am assuming here the sync speed thing is not too important as the results stil lshow good results

he used a normal 300watt strobe at full intensity

1/1250 at f7.1
3 stop under

getting a dark moody background and enough exposure on the foreground model

the hensel strobe we will be using fo rthe shoot is much more powerful

a pdf demonstration of his findings can be found here 1.2MB download

http://www.zeduce.org/images/experimental/High speed sync.pdf

thanks everyone for your help, it's much appreciated

Wendelt you can up the shutter speed as i have done in the past on the D2X it is in menu not sure which one but the flash and i think it is FP or something and you can up the shutter.

wendellt wrote:the results stil lshow good results

They do? At first glance these look like crap.

The top of the frame isn't getting any flash. Is that because of where the flash was positioned, or is it because the flash hasn't fired by then as the shutter slit travels vertically across the frame?

getting a dark moody background and enough exposure on the foreground model

Probably only if you put the model at the bottom of your frame!

the hensel strobe we will be using fo rthe shoot is much more powerful

The power won't be the only thing that will be different: the time it takes from the camera sending the "fire" signal to the light starting to ramp up out of the flash (and the discharge profile) will have a large impact on the results if you're trying to "cheat" the shutter behaviour like this. Even the D2H/D2X difference may end up being significant.

As Gary pointed out, you're trying to operate the equipment outside its design parameters, so there are no guarantees unless you manage to obtain the desired behaviour with the exact equipment you'll be using on the day.

My advice: stay within the design limits of the equipment - use an ND and increase the flash power to compensate. Simple and easy!

BBJ: I think "FP" is for use with flashes like the SB800 - not for studio flashes like this.

yep
fp
is a smoke and mirrors thing cooked up with the d2x and sb800
you get higher sync by the sb800 firing off a bunch of lower powered flashes to achieve flash sync but at greatly reduced range.

Steve

DaveB wrote:

wendellt wrote:the results stil lshow good results

They do? At first glance these look like crap.

The top of the frame isn't getting any flash. Is that because of where the flash was positioned, or is it because the flash hasn't fired by then as the shutter slit travels vertically across the frame?

getting a dark moody background and enough exposure on the foreground model

Probably only if you put the model at the bottom of your frame!

the hensel strobe we will be using fo rthe shoot is much more powerful

The power won't be the only thing that will be different: the time it takes from the camera sending the "fire" signal to the light starting to ramp up out of the flash (and the discharge profile) will have a large impact on the results if you're trying to "cheat" the shutter behaviour like this. Even the D2H/D2X difference may end up being significant.

As Gary pointed out, you're trying to operate the equipment outside its design parameters, so there are no guarantees unless you manage to obtain the desired behaviour with the exact equipment you'll be using on the day.

My advice: stay within the design limits of the equipment - use an ND and increase the flash power to compensate. Simple and easy!

BBJ: I think "FP" is for use with flashes like the SB800 - not for studio flashes like this.

Hi Dave

it was a test shoot the tone looks good to me nothing some post processin gcant fix
with the actual hensel lights iam sure i can use this test as a guide to what i can achieve with the better strobes

i'm not too concerned with the black veil
remember my lighting guy was using a 1/1250 shutterspeed way beyond the limit
I only need to use around 1/500 to get the tone i want
I am sure i wont be getting that black veil

will investigate the Nd filter idea too

even though i think it will reduce the overall darkness ofthe scene model and background and any amount of exposure compensation will not produce the desired result

DaveB wrote:

wendellt wrote:the results stil lshow good results

They do? At first glance these look like crap.

The top of the frame isn't getting any flash. Is that because of where the flash was positioned, or is it because the flash hasn't fired by then as the shutter slit travels vertically across the frame?

Dave, I think you're spot on in your reading of these images.

If you look at them sequentially as the exposure has been changed, you can (this is how I'm reading this) see the shadowed area creeping down further encroaching into the frame, thereby further reducing the actual light being captured by the sensor.

This is certainly not the sort of effect that I'd be wanting in any of my images. It reminds me of my M645 which had a faulty shutter, repaired twice, and then returned because it still refused to properly synch at 1/60. From what Wendell has described, this is simply not the effect that he's seeking.

Wendell,

wendellt wrote:it was a test shoot the tone looks good to me nothing some post processin gcant fix

Bets, people?

i'm not too concerned with the black veil

You should be.

Can you name the one acceptable substitute for correctly exposing your image in the first instance?

remember my lighting guy was using a 1/1250 shutterspeed way beyond the limit

And that's precisely the point.

We've now pointed this out several times, so please pay careful heed to this most imporant facet of what you're attempting to do.

It's a bit like expecting a politician to say something honest. It simply cannot happen.

I only need to use around 1/500 to get the tone i want

Which says that a test at 1/1250 was a total waste of time. Why wasn't it done at 1/500?

But - and this is extremely important - the shadow was extending further into the frame as the lighting was reduced. This does not suggest that you're going to be ok at 1/500, but trather that the problems may still exist at that speed.

Question: are these shadows caused by the first curtain not yet being open at the time the flash was fired, or by the second curtain closing prior to the flash being extinguished?

I am sure i wont be getting that black veil

And what gives you that feeling of certainty?

From what I'm seeing, your attitude to this is more like whe you pee in your pants. It feels nice and warm at first, but it's not at all a good outcome at the end of the day.

even though i think it will reduce the overall darkness ofthe scene model and background and any amount of exposure compensation will not produce the desired result

Wensll, a number of rather experienced people here are telling you that what you're trying isn't going to produce the desired outcome, but that the ND filter most likely will.

You're disagreeing with that PoV.

Sit down and have a serious think about this.

wendellt wrote:remember my lighting guy was using a 1/1250 shutterspeed way beyond the limit
I only need to use around 1/500 to get the tone i want
I am sure i wont be getting that black veil

No, you won't get THAT black "veil", you'll get a DIFFERENT one!
Different camera model, different flash, different shutter speed: they can all be significant when you're outside the design parameters of the camera like this. Even changing the flash power can even affect WHICH vertical bits of the frame are lit by flash.

With a shutter speed higher than X-sync, as Gary described the problem is that the sensor will only be partially uncovered when the flash goes off. The other suggestion of using a full-power flash burst (thus 1/980s long - lower power is done by a shorter flash burst) will work if you use a shutter speed faster than that (which doesn't sound like what you want as your backgrounds will be TOO dark, unless you up the ISO) and if the flash starts firing before the shutter starts to open and finishes after it closes (thus it's very timing dependent!). You're above the X-sync speed so the camera manufacturer has said it simply won't work. I'd prepared to back them on that, unless you can control ALL the factors very closely and are E X T R E M E L Y lucky.

will investigate the Nd filter idea too

even though i think it will reduce the overall darkness ofthe scene model and background and any amount of exposure compensation will not produce the desired result

Try comparing two scenarios compared to a base 1/250s exposure:

• Faster shutter speed (by one stop): 1/500s
  One stop less ambient exposure.
  The shutter will not be fully open when the flash goes off, so you won't get even flash illumination over the frame. The fudging described above would be very hit-and-miss.
• Same shutter speed (1/250s) but instead put a 1-stop ND on the lens:
  One stop less ambient exposure.
  You will need one stop more flash power to achieve the same illumination, but it will be even across the frame.

You've indicated there's lots of flash power available, so hopefully that won't be a problem. Note that you can increase the flash power by using the flash's power control, but you can also simply move the flash head closer to your subject and/or change the diffusion/reflection/etc!

As far as the ambient exposure (e.g. of the background) goes there is no difference between a faster shutter speed and an ND filter!

Wendell,
as Michael correctly said, you need to set the sync speed to 250 + "FP auto" on your D2X in CSM menu e1 (assuming the menu looks the same as on the D2H). The SB800 supports FP sync and will show an "FP" next to the "TTL" symbol, when it's set on the camera.

During FP the SB800 lets the flash bulb "burn" while the shutter slit travels across the sensor. Be aware that flash output/reach is greatly reduced and recycle times are longer.

FP high-speed sync (up to 1/8000s) has been a feature of Nikon pro SLR's for quite some time (I know the F5 had it) and the better flashes supported it.

Cheers
Steffen.

Steffen wrote:Wendell,
as Michael correctly said, you need to set the sync speed to 250 + "FP auto" on your D2X in CSM menu e1 (assuming the menu looks the same as on the D2H). The SB800 supports FP sync and will show an "FP" next to the "TTL" symbol, when it's set on the camera.

Except that, as Wendell stated, and as Michael acknowledged after it was pointed out to him, he is not using an SB800.

Please reread the very first post in this thread, and visit the link that Wendell provided.

Btw, if you are looking to purchase only one ND filter for digital I'd recommend an ND4 or ND8. The stronger ND filter gives you more flexibility which apertures/shutters speeds - you can always bump the ISO up a little if the filter is too strong since the quality of DSLRs around ISO 100-400 is generally very good. I settled for an ND8 myself.

this is a very simple exercise to balance your flash with the daylight, very easy if you have a flash meter, just balance the power output of the flash to the daylight exposure you wish to use.......... or if the flash is to strong move it back.........

gstark wrote:Except that, as Wendell stated, and as Michael acknowledged after it was pointed out to him, he is not using an SB800.

wendellt wrote:anyone know how to override the max flash sync speed on the D2X
it is limited to 1/250 for the sb800

I guess that's what I was replying to. Sorry if I didn't quite get the gist of the thread.

Cheers
Steffen.

hi guys

thanks for all your help

I discussed this with a few other studio photographers they all agree the use of a ND filter to Darken the background
and just use the strobe at max power and place it very close to the model

they suggested to shoot on a tripod static location one reference shot with no model and strobe light another with the model and strobe light positioned very close

the ND filter would darken the background while the light output from the strobe wiould illuminate the model quite well so i would get an unbalanced scene perfectly exposed model very dark and moody background.

then later in photoshop matte out the strobe light in the scene

thanks everyone