talk me out of changing to nikon! skateboard photography

[bsmotril]

Before changing brands, you might try panning to freeze the subject and put the blur onto the background.

[Andrushka]

I may be missing the reasoning of the OP and the follow-up posts, but for his info (and my own learning) isnt it possible to sync the camera at any speed with the 430ex set to High Speed Sync? i have shot with my digital rebel (i know!) and my 430ex at any shutter speed when i have the flash set to high speed sync... is there something about OP's set up that i don't understand that is limiting the sync speed? I just ordered a 30d and an st-e2, so any info on sync speed limits would be helpful to me as well...

[Wilt]

Originally Posted by Andrushka

I may be missing the reasoning of the OP and the follow-up posts, but for his info (and my own learning) isnt it possible to sync the camera at any speed with the 430ex set to High Speed Sync? i have shot with my digital rebel (i know!) and my 430ex at any shutter speed when i have the flash set to high speed sync... is there something about OP's set up that i don't understand that is limiting the sync speed? I just ordered a 30d and an st-e2, so any info on sync speed limits would be helpful to me as well...

The problem is that as you increase the shutter speed with any flash that has HSS, the output intensity of the light DECREASES significantly because it has to output a prolonged 'stream' of light over a longer duration of time.

[Andrushka]

so will his 30D/430ex sync at the high speeds still? I was under the impression it would - due to the flash's capability... so is his only problem that the perceived effectiveness/output of the flash is being diminished by the high shutter speed?

[bieber]

Originally Posted by Wilt

From DPReview info on D40x..."The Nikon D40 was announced just under four months ago, and yet here we are with a new version of that camera. The D40X has the same compact lightweight body and easy to use control layout, in fact the only external physical difference is the badge...

• Combined mechanical and CCD electronic shutter
• 30 to 1/4000 sec (1/3 EV steps)
• Flash X-Sync: up to 1/200 sec"

And DPReview info on D40..."The Nikon D40 is an all new affordable, compact, point-and-shoot digital SLR from Nikon, it follows on from the D50 but at a significantly lower price point and with a subtly different feature set...

• Combined mechanical and CCD electronic shutter
• 30 to 1/4000 sec (1/3 EV steps)
• Flash X-Sync: up to 1/500 sec"

The sensor type (CMOS vs. CCD) is not the sync speed villain, or the D40x would still have a 1/500 synch speed (but it doesn't).

So while it may be true that the D40 has a great sync speed, it is the ONLY Nikon to have it at an affordable part of the price range (like Canon!) and you would have to settle for an outdated 6Mpixel camera with not-terrific low-ISO performance in exchange for a sync speed.

Heh, I never said that it was a great camera, just that it made really high shutter speed flash sync possible. And we have to consider the possibility that the D40X does still have an electronic shutter, and they just choose not to advertise it (the original 1D can sync at just about any shutter speed, yet they still only advertise 1/300)

[Curtis N]

Originally Posted by Andrushka

so will his 30D/430ex sync at the high speeds still?

It will, but the range with HSS is about half what you could get with normal flash at X-sync speed. Combine that with a wide zoom setting and competition from the sun, and it just won't have much reach.

[Andrushka]

Originally Posted by Curtis N

It will, but the range with HSS is about half what you could get with normal flash at X-sync speed. Combine that with a wide zoom setting and competition from the sun, and it just won't have much reach.

thanks a lot curtis! Im glad that is the only issue - thanks!

Does anyone find it ironic that a photographer can drop shutter speed down at an airshow to get prop blur, and yet retain a crisp image of an aircraft, and the OP is struggling with motion blur at 1/250 on a skate boarder? is it a distance to subject issue or what? I am still trying to fully grasp the effects of relative shutter speed vs. light vs. distance to object - any thoughts?

[Moppie]

Originally Posted by Andrushka

I am still trying to fully grasp the effects of relative shutter speed vs. light vs. distance to object - any thoughts?

It's mostly a distance to subject thing.
But, its also an accleration thing. While a plane can move at several hundred miles an hour, the human body can out acclerate it.
So its very easy to follow a plan, and track as it changes speed, turns, climbs etc.
Try following someones arms as they wave them around in front of you.
It this rapid change of direction and speed that makes panning difficult and leaves arms and legs blurred in many sports photos.



Re: Converting to Nikon to get a faster sync speed, there is one thing to note:
The fastest avlaible on the noinks is 1/500th.
If a 580 fires at 1/800th, even with a shutter speed of 1/250, the flash exposure is taking place at 1/800th. or 1/300th of a second faster than the Nikon.

[tonylong]

Yeah, I don't know if Archie is still watching this conversation, but it seems natural for him to at least try out a 580. It has more power, so High Speed Synch may meet his needs.

[archie]

I am indeed watching this thread and have learnt quite a lot. I will try to borrow a 580ex to do some tests. And do as Circa has suggested in a another thread - try using two of my existing sunpak 383 flashes set to half speed to reduce their flash duration and maintain full power light output.

However I am still finding it difficult to get my head around the 'flash duration' concept as the motion blur would be visible at 250th of a sec regardless of their being flash present or not. Can anyone explain this to me here?

[Wilt]

Originally Posted by archie

I am indeed watching this thread and have learnt quite a lot. I will try to borrow a 580ex to do some tests. And do as Circa has suggested in a another thread - try using two of my existing sunpak 383 flashes set to half speed to reduce their flash duration and maintain full power light output.

However I am still finding it difficult to get my head around the 'flash duration' concept as the motion blur would be visible at 250th of a sec regardless of their being flash present or not. Can anyone explain this to me here?

Daylight with fill flash is truly two exposures in one. One exposure is with the flash. The second exposure is with the ambient light. So if there is enough ambient light to register on the sensor at 1/250 (which there certainly would be even at ISO 100...sunny 16 says 1/100 f/16 or 1/200 f/11) it will register motion blur even if the flash was going off at 1/1000.

[tonylong]

Archie, you mention sunpaks, does that mean you're using them for slaves? If you have slave flashes and then set your camera and 580 to High Speed synch, it seems like you would have your problem solved, since the slaves can have a high power output. But, I'm not experienced in flash photography. I'm trying to learn, so keep us posted!

[archie]

I wish it was solved Tony. The problem with shooting the sunpaks as slaves at any shutter speed above 250th is that you get an obvious black band at the bottom of your images from your shutter curtains.

[René Damkot]

Originally Posted by Moppie

Re: Converting to Nikon to get a faster sync speed, there is one thing to note:
The fastest avlaible on the noinks is 1/500th.
If a 580 fires at 1/800th, even with a shutter speed of 1/250, the flash exposure is taking place at 1/800th. or 1/300th of a second faster than the Nikon.

So?

First off, as noted, some Nikons with CCD sensor will sync at any speed (as long as the camera isn't aware there is a flash > PC sync cord, no TTL). Same as a 1Dino. (Link)

Second: A nikon flash has roughly the same flash duration as a Canon flash, so no difference there. You'ld still get a stop faster shutterspeed, so less motion from the ambient.

Third: A flash like the 580 or SB-800 at full power has way less freezing capability then the same flash at half power, since the flash pulse isn't "cut off", but 'dies slowly" (Link), and Link with examples


So you'ld want an as high as possible sync speed, so you can use 'normal (not High Speed Sync) flash, at as low power as possible: Flash duration on a 580EX.

If you are going to use HSS, the motion freezing is going to depend *entirely on your shutterspeed*. The flash won't do it for you. (Link).

[Moppie]

Originally Posted by René Damkot

So?

If the problem is action not being frozen by the flash, then moving to a higher sync speed will not help, and nor will using HSS.
As your links (which were extremely interesting) show the best way to stop motion with a flash is to use a regular sync speed and rely on the flashes very short duration to stop the action.

If the intention is to use ambient light and fast shutter speed to freeze the action, and the flash is only going to be used for fill, then HSS sync will work, and there is no need for a fast sync speed except to save flash power (as recycle times are longer with HSS).


One thing to note about electronic "shutters" on CCD sensor cameras, its often very easy to get a shutter speed faster than the flash duration, especially if the flash is used at full power. This can effect exposure, as the sensor is turned off before the flash finishes out putting all its light (this is easily demonstrated with a digital compact with manual or Tv mode, and a flash on an optical trigger).