Draggin' the shutter

[Mark McCall]

Calling jbarton248...
Here's the graphic explaining the term "Draggin' the shutter".

Simply stated, this is the use of a slower shutter speed to allow ambient light to be recorded in the background.
Notice the aperture value does not change...only the shutter speed changes.

[KellyL]

Mark, I am not Jbarton, but I am curious, how would you explain these pictures in regards to lighting ratios? This also helps me understand what.....hmmmm....name escapes me....Michael, I think....said, let the aperture control the flash, let the shutter control the ambient. Now that makes sense. Since the flash bursts for such a short time, it matters not what the shutter speed is. So....now that I am thinking through this...the first one was correctly exposed for the flash. Then, by dragging the shutter, you introduce the ambient light without having any effect on the flash? Yes or no?

[Mark McCall]

Originally Posted by KellyL

by dragging the shutter, you introduce the ambient light without having any effect on the flash? Yes or no?

That is correct.
This works best if you don't put your subject right under a spotlight.
Keep them off the stage, and you'll be able to drag the shutter to get your background just right.

Originally Posted by KellyL

Since the flash bursts for such a short time, it matters not what the shutter speed is.

Sort of.
Shutterspeed doesn't matter in the studio.
If your using a low ISO, only flash will be recorded with studio flash, and your shutterspeed doesn't matter, as long as you don't get into ridiculously long shutterspeeds.
Hope that makes sense.

[harryd]

Mark I am going to have to try this, are you using 2nd curtain sync? Also what happens if your subject moves some, is it a problem?

[Mark McCall]

Harry,
I'm using first curtain sync.

The camera is on a tripod, so the subject would have to be moving quite a bit for ghosting to appear, even in the 1/4th shot. It just never happens in a posed shot.

[Worm324]

Very interesting Mark and thanks for sharing!!

I'm wondering does the flash also keep the subject appear to be in focus??

Thanks,

Jay

[harryd]

Thanks for the explanation Mark. I have heard of this but never tried it and your results are fantastic. I appreciate your help.

[movingex]

Originally Posted by Mark McCall

Harry,
I'm using first curtain sync.

The camera is on a tripod, so the subject would have to be moving quite a bit for ghosting to appear, even in the 1/4th shot. It just never happens in a posed shot.

Hi Mark,

Great post, very informative.

I have heard that you sometimes might get ghosting if the subject is in from of a bright background when using shutter speeds below 1/30 or so.

I frequently use this method in events like parties and such but I rarely go below 1/30 and I'm never using a tripod because I'm moving around.

[clarebear]

wow- mark thank you for taking the time to put the example together! very helpful and informative.

clare

[BJ Pulsipher]

Okay, I'm glad you said you were on a tripod, otherwise I would have been very confused. Is doing the the same as using the night portrait mode on the camera?

[PavelOlavich]

This is a must-have skill for all wedding photographers. Otherwise flashed images will have that burned in look, as if the couple are posing in a dark cave.

[harryd]

Ok, time for a stupid question if you have time to teach me something. I will be shooting RAW and know I can change it later, but, how do I set the white balance? My flash is 5600k and tungsten in the church is 2850K. I know how I would do it but would love to know how you are suppose to do it. Part B, can I shoot a custom white balance while dragging the shutter?

[PavelOlavich]

You can use a WB card as a first test picture for a given venue, and use it to calibrate future shots. Often I just put the camera in Auto-WB, as it is often close and will not effect exposure too much.

Then I dial WB in during RAW conversion, doing the first in a series and using the same temperature going forward.

Yes, you can use a custom WB when dragging the shutter, but often one runs into mixed lighting, since the flash is the primary on the subjects, and the ambiant for the background. This is not hard to mitigate however. Shoot RAW!

[Mark McCall]

Originally Posted by BJ Pulsipher

Okay, I'm glad you said you were on a tripod, otherwise I would have been very confused. Is doing the the same as using the night portrait mode on the camera?

I wish I could tell you..but I can't. I've never used a night portrait mode.

[Mark McCall]

Originally Posted by harryd

how do I set the white balance? My flash is 5600k and tungsten in the church is 2850K. I know how I would do it but would love to know how you are suppose to do it. Part B, can I shoot a custom white balance while dragging the shutter?

Create a custom white balance based on the Kelvin temperature of your flash.
For Canon, the steps are as follows:
Shoot a white sheet of paper, fill the frame with the paper, expose normally using your flash.
Menu>Custom WB
On the LCD, the last photo you took will appear. (the white paper).
The words "Select an Image" will appear.
Click the OK button.
The words Select Custom WB will appear.
Use the top LCD on your camera to navigate to Custom White Balance.

Now, your flash will be balanced for flash.
Subjects will appear with normal color temperature, but the background will take on the color temperature of the ambient light...usually a golden hue.

Do not create a custom white balance when dragging the shutter.

Yes, this can all be done in PS or a Raw converter...but your best bet is to always get it as close as possible in camera.