Manual Mode & Flash - Confused!

DarknFuzzy

DarknFuzzy

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OK, lets see if i make some sense here.

Camera in Manual Mode, I take a meter reading for exposure, set my aperture to 2.8 and then adjust my shutter speed until i have correct exposure. Simple.

Now then, why is it when i attach my ST-DG 500 and turn it on the metering is exactly the same? If i put my exposure up to min sync speed of 1/180 it says it will be under exposed by at least 3 stops but yet if i take the picture it is exposed fine. I'm confused.:nuts:

Can someone explain this to me? Assuming i'm making sense that is. :shrug:
 
Metering in camera is for ambient light and NOT what the flash will do. If the meter says under exposed the flash will pump out more light to compensate. Basically you decide how much of the ambient light to capture and the flash does the rest.
 
Right, thanks.

So basically, if the metering reports -2.0 the flash will automatically compensate for the rest?

Edit:

While we are on the subject. In order to use fill flash in manual, is the just setting your flash exposure compensation to -1.0 for exmaple?
 
Yes, the flash will compensate but bear in mind the flash will expose for whatever part of the scene is first to return light, if you've got a big white object close the flash it will likely underexpose as a result.

To control the fill in manual you set the exposure for the scene and then use the flash EC to control how much affect the flash will have, -1 is a good starting point for fill flash in daylight but might not be so good in a dimly lit room and/or if the flash is being bounced.
 
That has really helped me get my head around it, thank you for taking the time pxl8. :)
 
If your flash has a high speed sync setting (like those from Pentax/Samsung), when in the camera's manual mode you'll be able to set a shutter speed higher than 1/180. Combined with a neutral density filter on your lens, you'll be able to user wider apertures in daylight and still use fill, provided you're within range.
 
I have a Sigma ST-DG 500 so 1/180 is my highest shutter speed, i guess it is these kind of things that you dont realise when you are first starting and buying your gear.
 
DarknFuzzy said:
I have a Sigma ST-DG 500 so 1/180 is my highest shutter speed, i guess it is these kind of things that you dont realise when you are first starting and buying your gear.
Click to expand...

Exactly what happened to me! I bought the Sigma flash and it was great.. till I realised that outdoors in the sun I needed a fast shutter speed on the camera so I didnt over expose the background... and thats where the Canon 580exII came in with its high speed flash. (y)
 
LOL - I keep my manual mode mostly for flash. 1/125th sec and somewhere between f5.6 & f8 and let the flash sort the rest out...
 
Byker28i said:
LOL - I keep my manual mode mostly for flash. 1/125th sec and somewhere between f5.6 & f8 and let the flash sort the rest out...
Click to expand...


I ahve mine on high sync .. shutter 250, iso 400, f5.6 works perfect indoors for head shoulders, presentations stuff like that.... anything else i am stuck... :(
 
I have a problem with flash when trying to shoot active sports shots outside. Lets say a paraglider taking off. There is a fair bit of movement and the camera is pointing to the sky at some point so a fill flash is req to bring out the facial shadows.

I think the max speed on a 40D is 250th?

40D with a 580II

any ideas?
 
The 430 will do high speed sync and so will the top end Sigmas (y)
 
admirable said:
I have a problem with flash when trying to shoot active sports shots outside. Lets say a paraglider taking off. There is a fair bit of movement and the camera is pointing to the sky at some point so a fill flash is req to bring out the facial shadows.

I think the max speed on a 40D is 250th?

40D with a 580II

any ideas?
Click to expand...

The max speed on the 40d is indeed 1/250th but if you put the 580EXII in high speed mode (just the press of one button on the rear) you can then dial in faster shutter speeds in your camera. (y)
 
Cheers for that, must get the book out!
 
KIPAX said:
I ahve mine on high sync .. shutter 250, iso 400, f5.6 works perfect indoors for head shoulders, presentations stuff like that.... anything else i am stuck... :(
Click to expand...

When you're using something like 24mm for a group shot you can use 1/60 or less and make use of the ambient light as well - but that'll probably mean an orange filter on the flash. Manually meter for 2 or 3 stops underexposure and it should look OK. Old SLRs had a 1/60 sync speed as the best compromise . . . for indoor flash (useless for outdoor fill).
 
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