Basic problems

Kev M

Kev M

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I never fail to disappoint myself when it comes to photography, especially when it involves flash photography. Looking through other peoples work and what settings they use I'm always surprised to see people using flashes on 1/8,1/4,1/2 power. It seems that whenever I'm using my lights I'm firing at full power, ISO400 and no lower than F5.6 in order to get the subject exposed properly.

On sunday I was firing an SB28 at full power into a reflective umbrella no more than about 8ft from the subject and I was struggling to get F5.6 on the meter (@ ISO400).

Admitteldy I was shooting a room with all the ambient properties of a cave entrance but it's my general habit to kill the ambient (especially indoors) so that I control the direction and size of all light sources. Am I asking too much of hotshoe flashguns to light a subject on their own? Have I got to learn to use the flash as an addition to the ambient light rather than a key light source of its own right?

Aside from artistic merit I see a massive technical gap between me and everybody else when it comes to the basics such as ensuring the subject is properly exposed.

Here's a test shot from the weekend.

ISO400
1/250
F5.6
1 shoot thru outside the window
1 SB28 in a collapsed reflective umbrella working it's arse off (to the right)
another flash to the left as a bit of fill.

4289832199_536487b479.jpg


In lightroom I reckon it needs +1.5 stops to expose the skin properly which then means I've royally cocked up the ratio to the window light but I'll worry about that when I've sorted my keylight issues.

Am I trying to light things in completely the wrong way with the equipment I've got?
 
Did you use a flashmeter Kev?
 
YYep, but I'm not convinced the meter is accurate with this camera, I think it reads at least .5 stop low. I need to do some more testing but my wife refuses to play ball as a subject.
 
I think it's faulty mate plain and simple it's clearly under exposing. You may get more power shooting through the brolley but an SB26 should cope easily with something that distance away especially with 400ISO

Have you got a shop you could go to and compare it with another one or a buddy who could loan you one?
 
The guide number for the SB-28 at ISO400 is 28 to 48m at 1/250, depending on the zoom head position. That's for the flash pointing at the subject, so should be reduced considerably when bounced/reflected.

Nevertheless, using 28 as the GN to simplify the maths, Distance = GN / aperture = 28 / 5.6 = 5m

Take into account the losses and I think you have your answer.
 
chivers67 said:
Have you got a shop you could go to and compare it with another one or a buddy who could loan you one?
Click to expand...

Don't think so. I suppose it could be as simple as a new battery being needed in the meter. I'll perhaps try some self portraits tonight in a scientific manner where I'm not trying to set up a sot and worry about a model at the same time.

Cheers for the info Photo. I think I'm going to have to do some geeky scientific testing to get to know my gear better.
 
Exif says 1/200th
 
Won't make any difference to the flash exposure though will it.
 
nope!
 
General comments:

SB-28 is not a very powerful gun.
8ft is not very close.
ISO400 at f/5.6 is quite workable.
All that picture needs is a reflector in front to make rather a nice shot IMHO :)
It's not an easy shot to meter, and half a stop is not a huge error overall.
If that's not your wife, marry her. Sorted :thumbs:

HTH :)
 
HoppyUK said:
General comments:

SB-28 is not a very powerful gun.
8ft is not very close.
ISO400 at f/5.6 is quite workable.
All that picture needs is a reflector in front to make rather a nice shot IMHO :)
It's not an easy shot to meter, and half a stop is not a huge error overall.
Click to expand...

Then there may well be a large degree of operator error. Time to go back to the drawing board.

If that's not your wife, marry her. Sorted :thumbs:

HTH :)
Click to expand...

Bigamy? Not sorted;)
 
Kev M said:
Then there may well be a large degree of operator error. Time to go back to the drawing board.
Click to expand...

TBH I think you're being a bit hard on yourself.

All that pic needs is a three foot silver reflector to the left of camera. Make one with cooking foil.

Maybe you need to bone up on using a meter, but if you can get within half a stop each time - which is about all you can realistically expect taking all the variables into account - then fine tune it off the LCD/histogram/blinkies. Ultimnately that is more accurate anyway.

Unless you're using a Bronica SQ-A of course, which makes life much more difficult. Polaroid back? ;)
 
Yeah, the models love it when, after I've finished faffing with the lights, I take a polaroid of them and ask them not to move for 120 seconds while I wait for the magic.;)

Most of the girls I've worked with don't even know what polaroids are, one of them asked if my Bronica was a "film" camera at the weekend. Not film as in 120 but film as in camcorder:lol:
 
I may be a thicko but to me there is no flash light there. How are you triggering the flash?
You may have preflash trouble.
 
I'm using skyports (definately no pre-flash issues). Trust me there is flash, you can see the light outside the window and if the one to the right hadn't gone off she'd be a silohuette, that room was like a cave!
 
It's a nice shot - well composed and a lovely subject!

How far away are the flashes? Remember the inverse square law... halving the distance will quadruple the light reaching the subject! So if you really do have them at 8ft from the subject then moving them to 4ft (still not that close) will have a huge effect!
 
Thanks Pete, not bad for a test shot I suppose. I was trying to keep the light source fairly small, hence the collapsed umbrella at that distance to try and stop it spilling everywhere giving bright, even illumination. I probably should have tried moving it closer but I was starting to flap a bit at that point as I had my mate helping me, the model freezing her arse off and two other photographers watching over my shoulder.
 
Just get a reflector in there! And get rid of that For Sale notice in the corner!
 
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