SunPak PF30x and shutter speed HELP!

[jconti3]

When I have my sunpak flash on my D90, 1/200 is my fastest shutter speed available. I have been to the flash settings and turned the sync speed all the way up and it does not help. Is it that my flash unit is not compatable?

[arith]

Actually I think it is 1/200 fastest on this flash. But original manufacturers might be faster.

[proseak]

When I have my sunpak flash on my D90, 1/200 is my fastest shutter speed available. I have been to the flash settings and turned the sync speed all the way up and it does not help. Is it that my flash unit is not compatable?

No, it isn't that, rather that the max X-sync on this cam is 1/200 sec. Here's the dpreview page;

http://www.dpreview.com/reviews/nikond90/page2.asp

[jiro]

John, can you be more specific as to what is the issue with your D90 and the sunpak flash unit?

[revi]

When I have my sunpak flash on my D90, 1/200 is my fastest shutter speed available. I have been to the flash settings and turned the sync speed all the way up and it does not help. Is it that my flash unit is not compatable?

Not likely:
normally, the duration of your flash is much shorter than your shutter speed. BUT shutters in a reflex are of the curtain type: first curtain moves, giving the light access to the sensor, then 2nd curtain follows to give the proper exposure. For slower speeds, there's a period where the sensor will be completely uncovered. For fast shutter speeds, there's no instant in which the full sensor is uncovered (the second curtain starts covering the sensor again before the first completely uncovered it). Using a flash in that situation would lead to a partially exposed image..

So that 1/200 s exposure is the shortest exposition where your sensor is completely uncovered (long enough to capture the flash, at least).

[Wirefox]

John

When I looked at that flash for my 450D I noticed that it will not sync at high shutter speeds. You need something like the 430EX or the 580EX for Canon or an SB600-900 for Nikon. The high speed sync will only be an issue when shooting with plenty of ambient light since in low light the flash burst itself will freeze the motion. I suppose it depends onwhat you are trying to do.

[proseak]

Um, the 450D also syncs at up to 1/200 sec - if you use a higher shutter speed, you'll get a picture of the shutter curtain. This limitation has always been in place for SLR cameras - doesn't usually matter too much, as you can change ISO in mid-shoot.

[jconti3]

Shutter • Electronically-controlled vertical-travel focal plane shutter
• 30 to 1/4000 sec (1/3 or 1/2 EV steps)
• Flash X-Sync: 1/200 sec
• Bulb
• Time (optional Wireless Remote Control ML-L3 required)
• Release time lag Approx. 65 ms
• Viewfinder blackout 120 ms
• Tested to 100,000 exposures
This would be the issue. I'm going to need to get a SB-?00 to get faster sync times is what i'm seeing.

[Colin Southern]

This would be the issue. I'm going to need to get a SB-?00 to get faster sync times is what i'm seeing.

Yes. You need a flash that handles what Canon call High Speed Sync (Nikon have an equivalent, but it's name escapes me just at the moment).

Basically, rather than giving a single flash, it gives a series of flashes in quick succession (that look like a single flash to the eye)

[revi]

Yes. You need a flash that handles what Canon call High Speed Sync (Nikon have an equivalent, but it's name escapes me just at the moment).

Basically, rather than giving a single flash, it gives a series of flashes in quick succession (that look like a single flash to the eye)

Would that be needed when your flash is the main light source? I always understood that the duration of the flash is way shorter than 1/200 s, so that even at a (relatively) slow shutter speed, motion will be frozen.

I can see you'd need HSS (term used by Sony as well) when the flash is used as fill light, and the main lighting is from ambiant light (which might give 'nice' PP problems, but that's another story). I'd also expect the flash intensity to be a lot lower in HSS, reducing the 'reach' of the flash: the same available energy has to be distributed over several impulses, each weaker than the full power single impulse in 'normal' mode.

John didn't say why he needed a faster shutter speed with flash, so he might or might not need HSS.

Remco

[Colin Southern]

Would that be needed when your flash is the main light source? I always understood that the duration of the flash is way shorter than 1/200 s, so that even at a (relatively) slow shutter speed, motion will be frozen.

It all depends where the light is coming from; if there's no ambient light then you could leave the shutter open for 5 years, and an exposure would only occur when the flash fired, and that would also freeze any motion. If there is ambient light , the freezing power transitions proportionately from the flash to the ambient light (then governed by the shutter speed).

I can see you'd need HSS (term used by Sony as well) when the flash is used as fill light, and the main lighting is from ambiant light (which might give 'nice' PP problems, but that's another story).

For a camera mounted flash, you need it anytime you try to shoot above X-Sync, or the camera won't let you go any faster For remotely triggered flash, once you go above x-sync you'll start to see the bottom curtain appear in the flash-illuminated portion of the exposure typically in the 1/250th to 1/400th range (varies between camera models); you can actually use this to your advantage if you want to go slightly higher than x-sync without HSS by turning the camera upside down - typically the top 1/3 of the scene will be sky (and thus doesn't need flash anyway), whereas the other 2/3 of the scene gets correctly lit by the flash. You'll get some weird looks, but it works!

I'd also expect the flash intensity to be a lot lower in HSS, reducing the 'reach' of the flash: the same available energy has to be distributed over several impulses, each weaker than the full power single impulse in 'normal' mode.

Yes - although flashes like the 580EX II are pretty grunty to start with, so it's not too bad in a fill-flash situation.

[jconti3]

John didn't say why he needed a faster shutter speed with flash, so he might or might not need HSS.

Remco

I dont know if thats what I'm lookin for. Just messing around with flash and DOF,action,fill light ect.....Also, how do you get close to the exsposure you're looking for with flash? Is the camera light meter adjusting for it?

[bambleweeney]

John didn't say why he needed a faster shutter speed with flash, so he might or might not need HSS.

Remco

I dont know if thats what I'm lookin for. Just messing around with flash and DOF,action,fill light ect.....Also, how do you get close to the exsposure you're looking for with flash? Is the camera light meter adjusting for it?

If you're using a Nikon SB(x)00 flash in Commander mode then the camera will control the exposure which is quite good in a lot of circumstances (zoomed flash and spot metering for example). Third party flashes are apparently a bit 'variable' on their ability to do this regardless of their iTTL claims. If your flash is not Nikon iTTL compatible then you can either set the flash to TTL or automatic exposure in which case the flash unit reads the exposure and turns itself off when appropriate (not ideal depending on what you're after)
For anything 'tricky' and static I set everything to manual and expose to get the background at the level I want. Then work out the guide number of the flash at the zoom ratio the flash is set to (actually I never do that, by the time I done the arithmetic the light has usually gone) OR, less sophisticated but waaaay easier, look at the camera LCD and either adjust the flash output or move it closer/further away until you get the light you're after.
Really depends what you're trying to do. For simple point and shoot with a little creativity the SB(x)00 flashes in Commander mode are excellent.

[Wirefox]

Um, the 450D also syncs at up to 1/200 sec - if you use a higher shutter speed, you'll get a picture of the shutter curtain. This limitation has always been in place for SLR cameras - doesn't usually matter too much, as you can change ISO in mid-shoot.

450D has HSS option. When coupled with a Canon speedlite it allows you to shoot above 1/200 by pulsing the flash as Colin explains above. Settings Menu No 2 / Flash Control / External Flash func. setting / Shutter sync / Hi-Speed