Video University: Video University Forums: Digital Photography for Videographers: FLASH QUESTION (I like all caps, it makes it look important)

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Home: Video University Forums: Digital Photography for Videographers:
FLASH QUESTION (I like all caps, it makes it look important)

Shadow
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Dec 9, 2006, 8:06 PM

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FLASH QUESTION (I like all caps, it makes it look important)	Can't Post

Ok, here's what I am finding. Is this normal??

I'm indoors or outdoors in fading light. I'm in av mode. I set to 2.8 but the shutter speed goes down to say 40 because of low light. My flash is in ettl mode but it doesn't bump up the shutter speed any.

So why, when there is a burst of light, is the shutter speed not compensated to allow for a faster speed?

I looked at a wedding photo I took outdoors (although I think I had my ISO back to 100 as I had just cleared settings and forgot to reset that), the shutter speed was at 1/15. I was really lucky the picture wasn't a blurr. :)
Must be that photography god.

Jenn M
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Dec 10, 2006, 1:47 AM

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Re: [Shadow] FLASH QUESTION (I like all caps, it makes it look important) [In reply to]	Can't Post

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the shutter speed was at 1/15. I was really lucky the picture wasn't a blurr. :)
Must be that photography god.

Or the flash stopped the motion.

I don't really understand your question... All I can offer is that you have to remember you ettl flash is reading the overall image (assuming you use evaluative metering) and the background light and/or reflective surfaces can affect the flash metering and therefore output - as well as camera settings if in AV or TV mode.

For one thing, it helps to shoot in full manual. And for another, you may want to lock your exposure using AE lock.

Anyone else can feel free to chime in and correct me if I'm wrong. Smile

Shadow
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Dec 10, 2006, 9:19 AM

Post #3 of 9 (630 views)
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Re: [Jenn M] FLASH QUESTION (I like all caps, it makes it look important) [In reply to]	Can't Post

Thanks Jenn

I'm terrible at explaining things sometimes. I'll try again.

Indoors, evening, room lights on. Reading says 2.8 at 1/8 shutter speed without the flash, taken in av mode.
Then when I put the flash on (in ettl mode) and take the picture, in av mode at 2.8 the shutter speed only increases to 1/15.

I'm confused why the shutter speed didn't increase to say 1/60 or something higher since now there is a burst of light.

??

(Hope this explains it better)
Cheers

Brian M
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Dec 10, 2006, 9:44 AM

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Re: [Shadow] FLASH QUESTION (I like all caps, it makes it look important) [In reply to]	Can't Post

It's Brian,
Jenn's still sleeping in but maybe I can answer (like I know something...ha ha ha)
I'll be sure to get her theory on this too. We're still learning flash, so this is soley a guess.

From what I understand, the av mode is a preset that does a calculation. I figure it's similar to an auto white balance feature on a video camera. If you are in very blue lighting, the auto white balance will do it's best to get the camera adjusted based on how the makers of the camera told it to fix the color (within an electronic chip)...it's good but it's not quite perfect and so you fix it later in editing. I'm guessing when they created TV and AV mode that they preset it to make a specific mathematical adjustment to compensate for the lighting conditions. Some photographers shoot a lot of their stuff below 1/60th, so I guess they can't assume that as an ideal setting.

I imagine if you set your flash compensation up to +2/3 or +1 that it would bump up the shutter closer to 1/60th (in AV mode) because the camera is getting enough light. However, bumping up your flash compensation in ETTL mode will give you more of a spotlight look. We heard it's always best to shoot with the flash compensated down a little (-2/3) to get a more warm look and we shoot almost always in manual. When below 1/60th the flash burst should freeze the action and significantly reduce that trailing affect that you normally get when shooting at say 1/15 without any flash.
Hope this made sence...I'll ask the expert later when she gets up. Wink

Brian M

________________________________________________
Photographer & Videographer

Shadow
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Dec 11, 2006, 11:19 PM

Post #5 of 9 (572 views)
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Re: [Brian M] FLASH QUESTION (I like all caps, it makes it look important) [In reply to]	Can't Post

Thanks Brian.

I see one of the photo shops is offering a class in Jan dedicated to flashes and the different settings. Think I'll sign up.

:)
Cheers
H

videochicke
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Dec 12, 2006, 10:02 AM

Post #6 of 9 (562 views)
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Re: [Shadow] FLASH QUESTION (I like all caps, it makes it look important) [In reply to]	Can't Post

Key is really to use the camera in manual. You choose the fstop and shutter speed. If the flash is on ettl, it will fire the correct burst to light the picture well. And if it doesn't, you increase or decrease the stops on the flash until it looks right.
Julie

Shadow
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Dec 12, 2006, 10:17 AM

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Re: [videochicke] FLASH QUESTION (I like all caps, it makes it look important) [In reply to]	Can't Post

Thanks Julie,
Do you find that in shutter priority mode, or aparature priority mode (on canon this is TV or AV mode), that the ettl works well?
I did a few family portraits over the weekend and did some shots with flash on and some with flash off, it was a bright day with harsh sun so it was tough to get good open shade. They turned out pretty good, but a few of them with the flash had their faces look a little hot in some spots.

I had my flash pointed up, maybe just slightly angled by one click towards them and used a sto-fen.

Thanks so much for your help.
H

videochicke
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Dec 13, 2006, 9:43 AM

Post #8 of 9 (542 views)
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Re: [Shadow] FLASH QUESTION (I like all caps, it makes it look important) [In reply to]	Can't Post

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It can work, but if you have it in TV or Av mode, you lose too much control. As an example, you are shooting indoors with the bride by a window. I want a fast shutter speed to see what is out the window. I want a wide aperature to blur the background a bit. The flash will do the rest. Or outdoors. I am shooting in the shade. But I want a nice blue sky in the picture. Again I need a fast shutter speed. If I want the background to be in sharp focus, need high f-stop. If I want the background softer, I want that lens wide open. Too much control is lost in AV and TV modes.
Julie

Shadow
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Dec 13, 2006, 9:56 AM

Post #9 of 9 (540 views)
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Re: [videochicke] FLASH QUESTION (I like all caps, it makes it look important) [In reply to]	Can't Post

Thanks Julie,
Do you mean too much control is lost in regards to the flash?
I understand the rest of it in terms of letting the auto setting do the work - I just wasn't sure if tv mode or av mode effected the flash or you lose something there regarding how the flash is working.

For some of the outdoor stuff I don't hve time time to meter so I'll put it in av or tv mode. If it is something artistic like someone in front of a window and I want to alter the settings then I'll use my light meter.

Thanks!!
H