Dark, DARK Exits?

Michelle Brooks Photography wrote in post #12469862
Very nice shot! I seem to be missing something, tho, on this method, along with some of the other images, which seem to have much more ambient light (at lease behind the subjects) than the situation we faced-- and that is how to get the focus on the subjects in the first place before your flashes go off. My first mistake, I see now, was using my 70-200 at a wide f-stop. Reckon if I'd had my 35 on at a higher f-stop it would've helped a lot.

Set your focus to your back (*) button instead of the shutter. You will thank me. Also, setting your f/stop to a higher number, while giving you more depth of field, will severely cut down on your ambient light. I often shoot these shots at f/2.8 (or lower if I use my 35L) just so I can bring in the ambient light.

Michelle Brooks Photography wrote in post #12469862
Very nice shot! I seem to be missing something, tho, on this method, along with some of the other images, which seem to have much more ambient light (at lease behind the subjects) than the situation we faced-- and that is how to get the focus on the subjects in the first place before your flashes go off. My first mistake, I see now, was using my 70-200 at a wide f-stop. Reckon if I'd had my 35 on at a higher f-stop it would've helped a lot.

This is where the hyperfocal distance thing comes in. Look at your lens and look at what the biggest number is in distance. I'd pick the lens with the smallest number - for me, it's the 16-35, because its hyperfocal distance is 3 feet. On the 50mm, it's 10 feet. Let's say you pick the 50mm. Focus on something that is more than 10 feet away from you. That will set your focus at that infinity point - so then anything that you shoot that is 10 feet away or more will be in focus. There is no need to focus again after that... as long as your subjects don't get close than 10 feet. I would want to be closer, which is why I like the 16-35.

This is how I do all my dancing shots. I set the focus, use f4 or f5.6, and as long as I'm 3 feet away, I get sharp dancing photos.

To get all that ambient light, use your highest ISO and slowest shutter speed. You can also boost your flash exposure compensation a bit and use a slower shutter than you would normally and get some motion blur, but your flash will freeze your subjects.

No, I do already use back button focusing, so that wasn't my issue. So you will use a wide f-stop on your wide angle? I thought you were saying that my 70-200 wasn't a good choice b/c I was using it at f2.8 but you just meant the lens itself wasn't the best choice, right?

jcolman wrote in post #12470006
Set your focus to your back (*) button instead of the shutter. You will thank me. Also, setting your f/stop to a higher number, while giving you more depth of field, will severely cut down on your ambient light. I often shoot these shots at f/2.8 (or lower if I use my 35L) just so I can bring in the ambient light.

This is a great expalantion of how to do this, Christina, thank you!

Christina wrote in post #12470293
This is where the hyperfocal distance thing comes in. Look at your lens and look at what the biggest number is in distance. I'd pick the lens with the smallest number - for me, it's the 16-35, because its hyperfocal distance is 3 feet. On the 50mm, it's 10 feet. Let's say you pick the 50mm. Focus on something that is more than 10 feet away from you. That will set your focus at that infinity point - so then anything that you shoot that is 10 feet away or more will be in focus. There is no need to focus again after that... as long as your subjects don't get close than 10 feet. I would want to be closer, which is why I like the 16-35.

This is how I do all my dancing shots. I set the focus, use f4 or f5.6, and as long as I'm 3 feet away, I get sharp dancing photos.

To get all that ambient light, use your highest ISO and slowest shutter speed. You can also boost your flash exposure compensation a bit and use a slower shutter than you would normally and get some motion blur, but your flash will freeze your subjects.

580EX on-camera AF assist helps AF lock in low light (only one-shot mode).

Michelle Brooks Photography wrote in post #12470324
No, I do already use back button focusing, so that wasn't my issue. So you will use a wide f-stop on your wide angle? I thought you were saying that my 70-200 wasn't a good choice b/c I was using it at f2.8 but you just meant the lens itself wasn't the best choice, right?

Yes, in my opinion, the 70-200 is too long a lens for nighttime exit shots as your DOF is going to be pretty narrow. Shooting at f/2.8 at 70mm is a lot harder than shooting at f/2.8 at 16mm as far as nailing focus in the dark on a moving subject.

i dont see how the AF-assist beam of the ST-E2 or any of Canon's shoe-mounted flash would help in this situation, as you will need to be in AI SERVO to keep the lens's focus moving.

I agree with trying a shorter FL, stopping down for more DOF. i'd also like to add that you may want to try and focus on a predetermined spot in their path and snap when they step in.

Many people successfully use One Shot mode for processionals, so I do not see why it would not work for exits.

emdzey01 wrote in post #12472197
i dont see how the AF-assist beam of the ST-E2 or any of Canon's shoe-mounted flash would help in this situation, as you will need to be in AI SERVO to keep the lens's focus moving.

I agree with trying a shorter FL, stopping down for more DOF. i'd also like to add that you may want to try and focus on a predetermined spot in their path and snap when they step in.

If you are walking backwards with the B&G then one shot mode works ok most of the time. The biggest issue however for using AI SERVO mode is having enough light for the camera to lock focus. At least in one shot mode you can use the AF-assist.

So...I'm a little confused as the whether it is best to use One Shot or AI Servo mode...I assumed AI Servo and keep the back button pressed once focus was acheived...

On the statement about the issue using AI Servo not having enough light to focus...is this why my husband's 7D won't fire at all if he hasn't achieved focus? I never use his, so I'm not sure if he's correct or not, but that's what he tells me.

Michelle Brooks Photography wrote in post #12476184
So...I'm a little confused as the whether it is best to use One Shot or AI Servo mode...I assumed AI Servo and keep the back button pressed once focus was acheived...

On the statement about the issue using AI Servo not having enough light to focus...is this why my husband's 7D won't fire at all if he hasn't achieved focus? I never use his, so I'm not sure if he's correct or not, but that's what he tells me.

Use one shot mode IF you are using your flash focus assist. Flash focus assist doesn't work in AI servo mode.

There is probably a custom function that is set on your husbands 7D to prevent it from firing if it doesn't lock focus. You can change it.

Michelle Brooks Photography wrote in post #12470324
No, I do already use back button focusing, so that wasn't my issue. So you will use a wide f-stop on your wide angle? I thought you were saying that my 70-200 wasn't a good choice b/c I was using it at f2.8 but you just meant the lens itself wasn't the best choice, right?

It may be helpful to check out a DOF calculator, too, like this one:
http://www.dofmaster.c​om/dofjs.html

If you put in the f-stop and distance for, say, 35mm and then 200mm, watch how the range of DOF changes.
At f2.8, subject 6 feet away, your range of DOF at 16mm is 11.3 ft
At f2.8, subject 6 feet away, your range of DOF at 35mm is 1.51 ft.
At f2.8, subject 6 feet away, your range of DOF at 70mm is 0.37 ft.
At f2.8, subject 6 feet away, your range of DOF at 200mm is 0.04 ft.