2nd Curtain Sync Flash - Why wouldn't you use it?

[martcol]

The selling-point for 2nd Curtain Sync is popping the flash at the end of the exposure so that any blur is before it. But thinking about it, I can't see why you wouldn't use this feature. What are the benefits of using 1st Curtain Sync or, why wouldn't you use 2nd Curtain Sync?

Regards

Martin

[tim]

Taking photos of a person would be better on 1st curtain - they're posed and ready and know when the photo's being taken. With 2nd curtain they might not be ready.

[timmyquest]

Taking photos of a person would be better on 1st curtain - they're posed and ready and know when the photo's being taken. With 2nd curtain they might not be ready.

Thats a stretch...were talking 100ths of a second here.

1st and 2nd curtain sync give you differnt effects, just like anything else on your camera ;-)

[edsarkiss]

similar to tim's reply -- if you are shooting any type of action in low light and you want to use a slower shutter speed to get some of the ambient light, 1st curtain sync allows you to freeze your subject the moment you press the shutter, rather than 1/30 or 1/4 second afterward (with the subject in an unpredictable pose/position).

personally, my camera stays on 2nd curtain sync 90% of the time ;-)

[timmyquest]

the moment you press the shutter, rather than 1/30 or 1/4 second afterward (with the subject in an unpredictable pose/position).



So you frequently shoot at 1/2 a second ???

[ppuga]

1st and 2nd curtain sync give you differnt effects, just like anything else on your camera ;-)


If I use 1st or 2nd, in a shot what will be the difference in the effect? Can you explain a little more?

thanks! :confused:

[tim]

Thats a stretch...were talking 100ths of a second here.

Not if you're taking the photo at night - exposure times of 1-2 seconds wouldn't be unreasonable to expose for the background. It is still a bit of a stretch though.

[martcol]

1st and 2nd curtain sync give you differnt effects, just like anything else on your camera

That much is obvious. The question is, why wouldn't you use 2nd curtain sync? Again, reading the manual the main difference seems to be that with 1st Curtain, you get the blur after the flash exposure and with 2nd Curtain you get it before. So in all other situations where you chose to use flash it really doesn't make any difference - or does it?

If it doesn't then I will continue to leave my cameras set at 2nd Curtain Sync because it seems to make sense to me.

Regards

Martin

[martcol]

If I use 1st or 2nd, in a shot what will be the difference in the effect? Can you explain a little more?

thanks! :confused:

When you shoot low-light photographs with 1st Curtain Sync the flash pops at the beginning of the shutter cycle. This gives the first part of the exposure, most noticable in long exposures, the desired exposure. Any movement in the shot will blur after the flash pops. In 2nd Curtain Sync mode, the flash pops at the end of the shutter cylcle. Any movement, most noticable in long exposures, will blur before this desired or optimum exposure point. This makes the blur precede the fixed point in the shot giving what is generally held to be a more pleasing effect. The example most often given and I think is in the 10D manual, is of a car moving. The 2nd curtain sync will leave a focussed, properly exposed car with a trailing light streaming away from the car. This gives a greater sense of movement and a natty effect of trailing lights. The 1st Curtain method will have a focussed subject obscured by movement blur.

But my question is, if you're not bothered about that effect, which mode is preferable or, does it matter at all?

Regards

Martin

[dhbailey]

If you're not bothered by that effect, it doesn't matter at all. The whole 1st-curtain/2nd-curtain question boils down to the effect you want.

If you don't care, then don't worry about it.

But 1st-curtain sync gives a sort of ghost-like effect on moving objects -- take a person walking across the frame, for instance, with a long exposure to get the background to show up. The person is exposed properly with the flash at the start of the frame but continues walking, so there is a blur ahead of the properly exposed body, sometimes looking as if the person's soul were leaving the body.

2nd-curtain sync gives you the blur following the body, so it looks as if they were superman speeding into the frame.

Again, though, if you don't care, why are you asking? Which mode is preferable depends on which effect you want. For most of us it matters greatly, that's why we own cameras which offer the option of 1st-curtain sync or 2nd-curtain sync. Which one we would use differs with different situations.

[martcol]

Again, though, if you don't care, why are you asking? Which mode is preferable depends on which effect you want. For most of us it matters greatly, that's why we own cameras which offer the option of 1st-curtain sync or 2nd-curtain sync. Which one we would use differs with different situations.

I still find my camera a complex beast that sometimes, in an attempt to make sure I'm getting it right, forces me to ask dumb questions on this forum. Going back over my posts I can't see where I gave the impression that I don't care. I do care. I care enough to want to learn more and I post here because I know that people like you can help me.

So to spell it out, I care because I also own a camera that gives an high degree of control (doh!). I'm not sure whether your post implies that I couldn't possibly care and you inteded to embarrass me. Still, I went public so...

Original question was: If you aren't looking for that effect with the blur (behind or in front of the flash) should you for any reason select 1st or 2nd curtain sync? Most of my daylight shooting I try to keep shutterspeeds as high as possible so, I don't suppose 1st or 2nd curtain sync matters (that doesn't mean I don't care). But if it does matter, outside of looking for that blur thing, what should I know.

Phew!

Regards

Martin

[Mike Panic]

i use rear curtain sync when shooting in night clubs, but thats about it - ive seen some people use it for night motorsports - but they are panning and shooting 1/10 to 1/30th of a second - in order to get it to give any kind of blur and not pan, you really need to shoot 1/2 second or longer exposures

for most events, first curtain works just fine, even when dragging the shutter down to 1/45 to allow more ambiant light to fill the back half of the photo

[Jon]

For high shutter speeds and slow-moving objects, it won't make much difference which you use. For stationary objects you want a mix of flash and available light, second-curtain will freeze any transient moving objects (people, vehicles, wildlife) at the end of their passage leaving a "more natural" ghost leading into the object; likewise with moving objects (see the classic "auto at night" in your manual). For environmental night portraits, say, first curtain sync will fire the flash closer to when you actually press the shutter; your subject will be more comfortable with this, and less likely to be caught with their mouth open, say ("Gee, your flash didn't . . . " *FLASH*). And while I trust Canon's reliability implicitly, I have a tad more confidence in a camera's ability to trigger the flash after the first curtain has reached the end of its travel than I do in its ability to realize that "yeah, the second curtain's about to let go; better pop the flash now" with any kind of consistency. Silly, I know, but there it is. You can manage the first with something as time-honored as a simple mechanical switch on the shutter cage; the second requires a bit more design sophistication.

[martcol]

Thanks everyone. That was very interesting and helpful!

Regards

Martin

[ppuga]

Thanks! I think now I understand the 1st and 2nd curtain flash usages. I will try it later.

Have a nice day.

[digitalfailure]

I have a quick question on this subject to, please forgive the n00bness

Does the 300D (without and external flash) off 1st and 2nd curtain flash?
I can't recall seeing anything relating to it.

[dhbailey]

"But my question is, if you're not bothered about that effect, which mode is preferable or, does it matter at all?"

That was the quote that made me think that Martin didn't care about the effect -- because if you're not bothered about that effect it doesn't matter which curtain you sync the flash with -- that effect is entirely the reason for the two different syncs.

I apologize if I misunderstood your comment.

[DocFrankenstein]

I have a quick question on this subject to, please forgive the n00bness

Does the 300D (without and external flash) off 1st and 2nd curtain flash?
I can't recall seeing anything relating to it. Methink not, unless you hack it.

[NGrinerPhoto]

just remember that you are not going to get the effect unless you are within 2 stops of the ambient light

[tim]

I have a quick question on this subject to, please forgive the n00bness

Does the 300D (without and external flash) off 1st and 2nd curtain flash?
I can't recall seeing anything relating to it.

You need to install the firmware hack - see the sticky link in this forum. It adds a bunch of useful stuff.

[Bodog]

You need to install the firmware hack - see the sticky link in this forum. It adds a bunch of useful stuff.
Unfortuntely 2nd curtain synch is not one of them :cry:

[tim]

Unfortuntely 2nd curtain synch is not one of them :cry:

Edit - it's in the customs functions menu, but it doesn't seem to work :( I wonder if it can be done directly on the flash (550EX)?

[sGu]

Just a quick link if you would like to see the difference between 1st and 2nd sync.

http://photography-on-the.net/forum/showthread.php?t=51572

2nd sync works wonders if there is ambient light mixed in the background :)

[Malaxos1]

I use second curtain flash all the time. I first discovered it several months back when I wanted to take a night photo of a mountain and lake. Th exposue was 15 seconds at ISO 400. The problem was that I wanted my wife and son in the photo but I knew that 15 seconds would be impossible. So, I used the second curtain flash to freez them after the 15 seconds exposure recorded the available light. Now I use it at weddings to bring in ambient light and freeze th action. If I knew how to post a photo on the new board I would post the photo of the mountain...Dean

[tim]

Dean - with the mountain surely it wouldn't make any difference if you used 1st or 2nd curtain sync? To attach a picture hit the post reply button, then hit the manage attachments button.

[sGu]

I use second curtain flash all the time. I first discovered it several months back when I wanted to take a night photo of a mountain and lake. Th exposue was 15 seconds at ISO 400. The problem was that I wanted my wife and son in the photo but I knew that 15 seconds would be impossible. So, I used the second curtain flash to freez them after the 15 seconds exposure recorded the available light. Now I use it at weddings to bring in ambient light and freeze th action. If I knew how to post a photo on the new board I would post the photo of the mountain...Dean

This is how you post image, first you need to have a host to display them, for example, http://gu.smugmug.com/photos/13161150-L.jpg is the address of the image, then you put tags around the web address, i.e http://actual address of image , without the space, you'll then have:

http://gu.smugmug.com/photos/13161150-L.jpg

[tim]

sgu, you can attach images that are saved on this server too - see my previous post.

[sGu]

sgu, you can attach images that are saved on this server too - see my previous post.

Won't that cause more workload to the server? Oh well, I already have my own host, with unlimited storage, might as well use it :)