Second curtain sync

Nostromo

Nostromo

Suspended / Banned
Messages
6,236
Name
Dominic
Edit My Images
Yes
Hi all, I was going to have a little play with second curtain sync/flash. I watched a couple of YouTube videos and now have more questions than when I started.
I was planning on do some simple things like rolling dice, bouncing ball etc indoors (nothing extraordinary).
I'm using a Canon 50d and yongnuo 685
So questions
1. Do I need to set the camera and flash to second curtain or just the flash.
2. Do I use ttl or manual (if it can be done in manual), I very rarely use ttl, so am more used to manual mode.
3. Can this be done off camera, i also have a yn622c-tx.

It's just for a bit of fun, and experience. I know lots of mistakes will be made, but you don't learn without trying.
 
1. Do I need to set the camera and flash to second curtain or just the flash. The camera, but the SS needs to be below 1/30
2. Do I use ttl or manual (if it can be done in manual), I very rarely use ttl, so am more used to manual mode. Either
3. Can this be done off camera, i also have a yn622c-tx. Yes

But...
Rolling of dice is a typical use of rear curtain sync, you have a recognised direction of travel.

A bouncing ball less so*, unless it's bouncing toward the camera.

Watch for an imbalance of colour temperatures.

* any 'random' movement can have a sharp subject with a moving image using first curtain sync, rear curtain sync is only required where there's an obvious direction of travel you want to show as frozen with a trail behind.
 
Thanks for that, it much appreciated.
The videos I watch all seemed to imply that the flash needed to be on camera and that you need to use ttl.
I'll try manual first then ttl and see which I'm happier with.
I was going for a trail behind the direction of travel, but will bear in mind about non directional movement.
Thanks again.
 
Nostromo said:
Thanks for that, it much appreciated.
The videos I watch all seemed to imply that the flash needed to be on camera and that you need to use ttl.
I'll try manual first then ttl and see which I'm happier with.
I was going for a trail behind the direction of travel, but will bear in mind about non directional movement.
Thanks again.
Click to expand...

It's camera/trigger dependent. It should always work in the hot shoe where all the right contacts are, but may not work wirelessly off-camera. The native Canon system actually doesn't allow remote second curtain sync (for historic patent reasons, I think) though most third party triggers offer it. You may or may not have to enable it in menus.

As Phil says, second curtain is not actually enabled until shutter speeds drop below 1/30sec, even when switched on, and it works best at longer speeds where the direction of travel is obvious, much less so with random movement. Another thing to be aware of using second curtain sync and auto-TTL, is the pre-flash. With people pictures, they often think the picture has been taken with the pre-flash and start to move before the main flash has fired. You can get around this by firing the pre-flash manually in advance (using the *star button with Canon).
 
Nostromo said:
Thanks for that, it much appreciated.
The videos I watch all seemed to imply that the flash needed to be on camera and that you need to use ttl.
Click to expand...

Was that you couldn't fire 2nd curtain wirelessly, but if you grab an OC-E3 cable, then you can still use 2nd curtain/HSS etc as if the flash is still on the camera. Swapped my standard Canon OC-E3 50cm for a Yongnuo OC-E3 1m job which is a handy bit of kit to have about and was only about £25 iirc
 
Top tip noted, I'll give it a try when I manage to find some time. :)
 
juggler said:
Top tip: try arranging to have your constant illumination and the flash light different portions of the subject, e.g. have the two lights directly opposite each other and the subject in between. That way you'll get a much sharper frozen image.

Here's one I prepared earlier...
https://www.talkphotography.co.uk/threads/blurry-dancer-more-added.656459/
Click to expand...

Did you use a continuous light at the back and a flash at the front Simon ? and what sort of setting did you use, in a few weeks I have to do a shoot with a ballerina who I work with and I would really like to have a go at this, never tried it before though so I'm very interested in the process. Cheers
 
TG. said:
Did you use a continuous light at the back and a flash at the front Simon ? and what sort of setting did you use, in a few weeks I have to do a shoot with a ballerina who I work with and I would really like to have a go at this, never tried it before though so I'm very interested in the process. Cheers
Click to expand...

Hi Tel, I did a fuller writeup including settings on my fstoppers profile: https://fstoppers.com/photo/182162
Feel free to ask any questions :)
 
Thanks Simon I will take a look [emoji106]
 
TG. said:
Thanks Simon I will take a look [emoji106]
Click to expand...
With apologies to the OP for going off topic .. Just be aware that this stuff has a rather low yield. In 3 hours I got maybe 7-8 images I was happy with. In a subsequent shoot with a pole dancer I made sure I had some other stuff in the bag first and then spent the last hour nailing just one blurry image along these lines.
 
juggler said:
With apologies to the OP for going off topic .. Just be aware that this stuff has a rather low yield. In 3 hours I got maybe 7-8 images I was happy with. In a subsequent shoot with a pole dancer I made sure I had some other stuff in the bag first and then spent the last hour nailing just one blurry image along these lines.
Click to expand...
It's quite alright, it's an interesting topic, so all info is good in my book.
 
juggler said:
Hi Tel, I did a fuller writeup including settings on my fstoppers profile: https://fstoppers.com/photo/182162
Feel free to ask any questions :)
Click to expand...

I have taken a look Simon, and very interesting write up, a couple of questions am I correct in thinking when you set the shot up you get the model to stand where she will land then manually focus that position, obviously you would be using a tripod for this, then you take the shot as her head comes into view to the landing position, also I haven't got a SF studio light the most I have is the Lencarta 300watt elite pro 2, and what sort of power did you need on the continuous light from the back, did you have any problems with mixing the flash and continuous light rendering the colour balance ?
 
TG. said:
I have taken a look Simon, and very interesting write up, a couple of questions am I correct in thinking when you set the shot up you get the model to stand where she will land then manually focus that position, obviously you would be using a tripod for this, then you take the shot as her head comes into view to the landing position, also I haven't got a SF studio light the most I have is the Lencarta 300watt elite pro 2, and what sort of power did you need on the continuous light from the back, did you have any problems with mixing the flash and continuous light rendering the colour balance ?
Click to expand...

Yes, I used a tripod.

The first step was to study the model's movement without shooting, and then to find a way for her to move which she could - as nearly as possible - reproduce exactly, including the little cues she was giving with her hands as she started moving.

I pre-focused on the final position; I nearly always use back button focus.

I opened the shutter after she'd started moving - I didn't want a bright patch where she was stationary. The shutter speed was timed to catch the peak. I made fine adjustments to the timing by watching the cues she was giving and used rear curtain sync.

With other similar shots I removed the trigger and fired the flash manually as the head hit the correct point. That resulted in a slight trail ahead of the flash position but for some shapes it didn't matter and it made the timing a lot easier. For some shapes I found it easier to use mirror lockup, for others that made little difference.

I suspect that the Elite Pro 2 has minimum flash duration at maximum power but DYOR. You may get on better with a brace of speedlites at low power.

The constant light was fixed at 800W. It was heavily flagged and had barn doors so a fair bit of that will have been absorbed.

I put a 1/2 CTS gel on the flash for colour temperature matching. It looked enough at the time but I had to make some adjustments in post.

Things I would change next time:
  • I'd use more gel for colour correction
  • I'd try to come up with a lighting scheme which didn't result in monster lighting on the face. I suspect that would need a second flash overhead and very close, and would be difficult to get right.
  • I'd use a different constant light. I don't like the slight banding in the trails which results from the 50Hz mains through an incandescent bulb.
hth
 
That's a fantastic image Simon. I've done a similar one in the past, but not as refined as yours.

Interesting you got flicker from a redhead light - I've used either the 150Watt halogen modelling lights in my SuperFasts or some 650Watt tungsten lights - on dimmers - to do this sort of thing and never seen that (and they are cheap as chips - literally bulb holders with a Fresnel arrangement). When you turn those off you can still see a glow over a second later, so 50 Hz only causes the slightest of ripples in brightness.
 
Scooter said:
That's a fantastic image Simon. I've done a similar one in the past, but not as refined as yours.

Interesting you got flicker from a redhead light - I've used either the 150Watt halogen modelling lights in my SuperFasts or some 650Watt tungsten lights - on dimmers - to do this sort of thing and never seen that (and they are cheap as chips - literally bulb holders with a Fresnel arrangement). When you turn those off you can still see a glow over a second later, so 50 Hz only causes the slightest of ripples in brightness.
Click to expand...

Thanks Owen!

I'm told that discharge lamps with electronic ballast would eliminate the issue - but modelling lights would be simpler and cheaper :)
 
juggler said:
Yes, I used a tripod.

The first step was to study the model's movement without shooting, and then to find a way for her to move which she could - as nearly as possible - reproduce exactly, including the little cues she was giving with her hands as she started moving.

I pre-focused on the final position; I nearly always use back button focus.

I opened the shutter after she'd started moving - I didn't want a bright patch where she was stationary. The shutter speed was timed to catch the peak. I made fine adjustments to the timing by watching the cues she was giving and used rear curtain sync.

With other similar shots I removed the trigger and fired the flash manually as the head hit the correct point. That resulted in a slight trail ahead of the flash position but for some shapes it didn't matter and it made the timing a lot easier. For some shapes I found it easier to use mirror lockup, for others that made little difference.

I suspect that the Elite Pro 2 has minimum flash duration at maximum power but DYOR. You may get on better with a brace of speedlites at low power.

The constant light was fixed at 800W. It was heavily flagged and had barn doors so a fair bit of that will have been absorbed.

I put a 1/2 CTS gel on the flash for colour temperature matching. It looked enough at the time but I had to make some adjustments in post.

Things I would change next time:
  • I'd use more gel for colour correction
  • I'd try to come up with a lighting scheme which didn't result in monster lighting on the face. I suspect that would need a second flash overhead and very close, and would be difficult to get right.
  • I'd use a different constant light. I don't like the slight banding in the trails which results from the 50Hz mains through an incandescent bulb.
hth
Click to expand...


Thanks Simon for a good informative overview, some food for thought, I also found this very impressive video on Karl Taylors YouTube channel, which pretty much reiterates the discussion

View: https://youtu.be/LpDqh90NsKM?list=PLQndF4yTYK1nrI57ul24yB201oeEcq2BY
 
Last edited:
juggler said:
That's where I got the tip about not letting the lights overlap! I knew I'd seen it somewhere :)
Click to expand...
I disagree with that... at least to an extent.
The only thing that matters is that the flash overpowers the ambient/constant by at least 1 stop (more is better/less translucent) where it falls. By side/rim lighting with the constant light you get a brighter, but less complete/more contrasty "trail" (depending on the ambient exposure settings). If the subject is lit more frontally with the constant light you get a dimmer, but more complete and even trail (no side highlights w/in the trail).

For your blurry dancer image, I think you might have preferred more frontal lighting for a smoother trail (no "flashes" where body parts catch the rim light as they move)... you already had the ambient exposure set to record some of the unlit front, which means a higher ISO or wider aperture than would otherwise have been required with more frontal lighting. And being able to use a smaller aperture w/ more DOF helps a lot in this scenario (the same flash power/duration would be required in both scenarios).

I hope that makes sense...
 
You must log in or register to reply here.
Back
Top