High speed flash sync.

[DaveW]

High speed flash sync. is not as good for stopping action as it's name implies. See:-

http://webs.lanset.com/rcochran/flash/hss.html

DaveW

[rjlittlefield]

Great demo of a hard-to-understand subject -- thanks for posting the link!

--Rik

[Bruce Williams]

Interesting link Dave - Thanks.

Bruce

[Epidic]

I think there is some confusion about high-speed sync. This allows faster shutter speeds to be used and that is it. You will find high-speed sync to freeze action better under bright daylight conditions as the ambient exposure is shorter. I am curious about the "experiment" as why would you want to freeze a spinning disk at 30,000 rpm with a 1/4000s shutter speed? Naturally there would be limitations. It is certainly not the conditions for high-speed sync. For fast high-speed photography, electoronic flash alone has always been a better tool, but it also cannot use ambient light - at least not with the shutters in normal cameras.
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Will

[Harold Gough]

If you want to freeze movement on fast moving subjects you may need special strobes (confusing because this term is used in some countries for ordinary electonic flash) , etc.

Her are some websites:

http://www.hiviz.com:80/

http://www.diyphotography.net/diy_high_speed_photography_at_home

http://www.astro.livjm.ac.uk/~rjs/HSP/


And we can't overlook:

http://en.wikipedia.org/wiki/High_speed_photography

[/url] http://www.gregscott.com/rwscott/flash.htm[url]

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It is likely that some, possibly all, of the above are represented in other strings.

Harold[/url]
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Happiness is having the right adapter.

My manual flash setup for high magnification:

http://www.photomacrography.net/forum/viewtopic.php?p=117843#117843

[arlon]

I just use regular flash for freezing motion on water shots. In a dim room, flash does all the exposing and does a great job of freezing things. The article Dave posted is all that got me to try water with my d200, Had been using the d50 at high shutter speeds like 1/4000 with the flash. D200 only syncs up to 1/250. Figured it was a waste of time to to try until I read what Dave posted. Walked right in and grabbed my trusty SB-20 flash and started shooting at 1/60, flash did it all.


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D50,100 IR, 90, 700, 800E and a box of old manual lenses.

[Harold Gough]

My focal plane shutters are severly limited, with flash synchronisation at a maximum of 1/30 sec (OM2n) or 1/60 sec (OM4). However, I have never found that a problem with ISO 100, or slower, film.
_________________
Happiness is having the right adapter.

My manual flash setup for high magnification:

http://www.photomacrography.net/forum/viewtopic.php?p=117843#117843

[cannyman]

Beware of Vivitar 283 if its the old model
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DIY GIZMO`S FOR USE IN PHOTOGRAPHY

[Harold Gough]

1) How do I recognise the old model?

2) All of my manual flash (with my Canon A1) was with twin flash, one Vivitar 283 and one Sunpack. I never had a problem. Since then, I bought a spare 283.
_________________
Happiness is having the right adapter.

My manual flash setup for high magnification:

http://www.photomacrography.net/forum/viewtopic.php?p=117843#117843

[Danny]

arlon is 100% correct.

Theres a slight difference between what some see as high speed flash and what others see. The guy is totally correct for what hes doing...........but and theres always a but. I was taught that high speed flash does not rely on shutter sync at all. Let me explain and this is how I read it at the time. He is actually doing high speed shutter and sync, not high speed flash IMO.

Don't set a shutter speed at all, that limits high speed flash. Theres also a huge difference between horizontal and vertical shutters compared to leaf shutters.

So don't set a shutter speed. Thats the whole secret to it right there. For ultra high speed flash you work in a dark environment, set the shutter to "B" and let the flash duration do the work. So if the shutter is left open, it has no control of the flash, the flash sync's at any speed you want. If you set it for 1/32,000th of a sec duration, thats exactly what you get.

Ahhh, the most interesting book on this is not a speciality book on flash at all, its a book called "Caught In Motion" by my hero, Stephen Dalton. Now hes in the UK Dave and is just incredible with how he stops insects and birds in flight.

Read his book and how he developed high speed flash and how he uses it. Incredible read and photography. He developed the high sync's with a friend of his from the RAF.

Anyway, gotta go, far too interesting this subject. BTW, all mine are done in the dark with the shutter fully open.

Danny.
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http://www.macrophotos.com

Worry about the image that comes out of the box, rather than the box itself.

[cannyman]

[cannyman]

[cannyman]

The moral of the story i, don`t drink ice cold beer if you wear dentures.


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DIY GIZMO`S FOR USE IN PHOTOGRAPHY

[Danny]

[DaveW]

I have Stephen Dalton's "Borne on the Wind" which is similar Danny. Many people do not realise when set up close to the subject and on manual low power just how short the flash duration that forms the image using a camera type flash gun can be, high speed sync shutter speeds can not approach this.

I did read but can't locate the article again that camera type flash guns are best for this type of photography, as though it is termed power settings on them it is a bit of a misnomer as the flash intensity is not reduced on "lower power" settings only it's duration as the flash is simply quenched quicker, hence the lowest power setting has the shortest flash duration for stopping action.

However it claimed studio flash works differently in that power settings on that mean the flash duration stays the same but their power (light output) is reduced. Therefore for stop action high speed flash a camera type flash gun on low power setting is preferable to studio flash because the flash duration will be a lot shorter. How true this is I do not know?

By the way Danny have you tried to photo a bullet coming towards the camera and stop it with flash, and if you do try where do we sent the flowers too?

DaveW