Studio Strobe HSS and Yungnuo 622c triggers

[Richee]

Hi, I'm trying to get my head around HSS. Here's what I think I know. On my speed-lights, I achieve HSS using the Yungnuo 622c triggers by making all the appropriate settings. It works because the HSS compatible speedlights emit a very fast series of bursts for the full duration of the curtains opening and closing on my shutter. That's fine for my speedlights.

I also have a Lencarta UltrPro 300 studio strobe and put it to the test with HSS. As far as I am aware this Strobe doesn't do HSS? However, even though they are not fully compatible with the 622c triggers, I can hook one up via a sync cord to get wireless triggering, and I have a UltraPro Commander Remote Control Unit, so remote control is mine. I set my shutter to 1/8000th and the Lencarta to full power and it appears to work, the image is under exposed but no black band. I note that if I set my shutter to 1/1000th (for example) the image is brighter and better exposed, still no black band at this shutter speed.

Now I wish to get it all straight in my mind. Here's what I think is going on. Because the Lencarta is set to full power it is emitting light for a much longer period and covering the shutter speed duration, so no black band. This would explain why I get a brighter image when I set my shutter to a longer period (1/1000th).

Am I correct in my thinking about this and what other issues am I likely to encounter using this method? I expect that if I want to achieve correct exposure at 1/8000th I would need to invest in proper HSS Studio Strobes (do they exist?). If they exist, any recommendations for value and expensive and what would spending more get me? Anyone aware of a web page that will give me all the proper information about this? I'd like to know what the tried and tested method of freezing action with studio strobes and triggers is please.

TIA

Richee

 

[Garry Edwards]

No, the Lencarta UltraPro doesn't have HSS - that's a property of IGBT flashes such as hotshoe flashes, not of conventional technology studio flashes.

What you are using is Tail End Sync, AKA Peak Hyper-sync (in Pocket Wizard-speak), and it works at any shutter speed with almost all conventional-technology studio flashes. You are wrong though in assuming that the under exposure that you're getting at lower flash power settings is due to shorter flash durations, the flash durations are in fact longer at lower power settings and the reason for your under exposure is simply that you haven't adjusted the lens aperture to suit the amount of light.

You can use shutter speeds as high as 1/8000th (just as you can drive at 140 mph along your local high street) but it isn't a good idea and you will get more even exposure at slower shutter speeds, personally I feel that 1/2000th is probably ideal. If you want a technical explanation of this just ask.

In the studio, there is no point whatever in using either HSS or Tail end synch - if you want to freeze action then your best option is to use the Lencarta SuperFast which, when turned down to a low power setting, produces incredibly short flash durations that will freeze movement. There are other options, such as the Alien Bees Einstein, both work in the same way and utilise IGBT technology, just as a hotshoe flashgun does.

 

[HoppyUK]

Hi, I'm trying to get my head around HSS. Here's what I think I know. On my speed-lights, I achieve HSS using the Yungnuo 622c triggers by making all the appropriate settings. It works because the HSS compatible speedlights emit a very fast series of bursts for the full duration of the curtains opening and closing on my shutter. That's fine for my speedlights.

Yes.

I also have a Lencarta UltrPro 300 studio strobe and put it to the test with HSS. As far as I am aware this Strobe doesn't do HSS? However, even though they are not fully compatible with the 622c triggers, I can hook one up via a sync cord to get wireless triggering, and I have a UltraPro Commander Remote Control Unit, so remote control is mine. I set my shutter to 1/8000th and the Lencarta to full power and it appears to work, the image is under exposed but no black band. I note that if I set my shutter to 1/1000th (for example) the image is brighter and better exposed, still no black band at this shutter speed.

Now I wish to get it all straight in my mind. Here's what I think is going on. Because the Lencarta is set to full power it is emitting light for a much longer period and covering the shutter speed duration, so no black band. This would explain why I get a brighter image when I set my shutter to a longer period (1/1000th).

Am I correct in my thinking about this and what other issues am I likely to encounter using this method? I expect that if I want to achieve correct exposure at 1/8000th I would need to invest in proper HSS Studio Strobes (do they exist?). If they exist, any recommendations for value and expensive and what would spending more get me? Anyone aware of a web page that will give me all the proper information about this? I'd like to know what the tried and tested method of freezing action with studio strobes and triggers is please.

TIA

Richee

Not quite. Image is brighter at 1/1000 over 1/8000 sec because the shutter is open longer, collecting more light. With both hypersync and high-speed sync, the flash is acting like continuous light for exposure. With conventional studio flash, as power is turned down, effective flash duration gets longer.

This is a confusing subject, not helped by a lack of agreed terminology and terms like high-speed sync and hyper-sync and peak/tail hypersync, super-sync and overdrive-sync etc, get mixed up. Even Garry has got it wrong when he mentions Peak Hypersync which is something different and unique to Pocket Wizard. To get a full grasp of this, you need to understand the output curve of a flash pulse, and overlay that with the scanning cycle of a focal plane shutter.

What do you want to do? Both hypersync and HSS are basically ways of using very fast shutter speeds, to freeze movement in bright ambient light. Neither is a perfect solution, both are very wasteful of flash output, and hypersync will always give you uneven exposure top-to-bottom of frame. There are workarounds that might be okay, but there is a better solution for studio work where ambient light is not a problem, ie a flash unit with fast duration, used at normal x-sync speed.

Suggest get a cup of tea and read this, from Pocket Wizard http://wiki.pocketwizard.com/?title=Understanding_HyperSync_and_High_Speed_Sync

 

[sk66]

I'd like to know what the tried and tested method of freezing action with studio strobes and triggers is please.

Sounds like you have a decent handle on things.

The "tried and true" method is strobes with very short flash durations in a very dark environment. Speedlights are great for this.
Your UltraPro probably has a T.1 time of ~ 1/1000 at full power so that's about it's "effective shutter speed" in a dark environment.