Tuesday, 6 March 2012

Fill Flash Fun

Fun, ohhhh yes. The more I read about it, the more convinced I become that using a flash for nature photography, even with a telephoto lens, is the way forward. For a start it's an excuse for to buy lots more camera crap - not really. From a variety of largely unsuccessful experiments last year I happen to have a flash already, and an extender, and an off-camera flash cord, and a funny flash bracket thing for macro. I just don't ever use them. Time to change all that, as at the weekend I did something that I've been threatening to do for a long time, and booked a holiday to the Caribbean. There are birds there, pretty ones - or so I've been told - and lots of them live in forests, and forests are dark. It would be remiss of me to go there and just laze around a pool, Mrs L wouldn't want that, no siree. If the bird rumours are true (and my heavily-thumbed copy of the Helm field guide to the Birds of Trinidad and Tobago that I bought last year appears to confirm this), then they will want photographing.

There is one problem - I don't know how to use a flash. Usually I am very scornful of people who have camera equipment they have no clue how to use - most birders these days lug digital SLRs around with them, and from the output that subsequently appears all over the web, it's clear that the vast majority of them fall into the unfortunately clueless bracket. All the gear, no idea, as the saying goes. I am ashamed to say that as far as flash photography goes, that pretty much sums me up. The good news is lots of expert people say that it's easy. I am not so sure, but in a bit of a departure from my planned regime of having no goals whatsoever, this year I am going to learn how to use a flash. And not just learn how to use it - I am going to become damned good at using it. All I require is a neverending supply of AAs......

A Hornbill in the garden recently provided the perfect opportunity to start trying to figure it out. The theory behind fill-flash is that you expose the scene normally, and add just a little bit of flash to lift the shadows. If the flash fails to go off, you should still get a properly exposed shot. Depending on your distance to the subject, you will need to reduce your flash output. There is probably a lot more to it than that in practice, but that at least is the theory.

There was no flash used here. Exposure was 1/400 @ f5.6, EV metering minus 1 2/3 stops.
The same exposure was used here, but this time the flash was on, but with minus 3 stops of flash exposure compensation.

The Hornbill then flew to a tree near the fence, and sat against a light background. A photographer's nightmare, and one that happens all the time. 1/400 @ f5.6. No flash. Look how dark the eye is!
Luckily the Hornbill stayed put whilst I fiddled with the flash. The exposure is the same, but the flash fired with minus 1 stop of flash exposure compensation. Minus 2 would have been better.

The Hornbill flew off, presumably to join the Turaco. Instead I concentrated on this palm leaf. Exposure was a mere 1/80s @ f5.6, which with 700mm of focal length is always going to be problematic. It's dull, and it isn't sharp.

This time I used the flash, with minus 1 1/3 stops of flash exposure compensation. You can see that the leaf and the brickwork are a little bit brighter, but the flash isn't really noticeable. An added bonus of flash is increased sharpness.
Obviously, these are illustrations that more or less worked. There were plenty of horror images as I struggled with compensation issues related (I think) to distance from the subject. How real photographers get it consistently right is beyond me. But hopefully much more practice will demystify it. The other question is is it worth the effort? Rather than wander around with a monopod and a lens, snapping a photograph as and when, this will require proper dedication. Unwieldy doesn't even begin to describe it - definitely for locations where you don't plan on moving around much! Like a bar stool in Tobago perhaps?

1 comment:

  1. That's what I love about photography - the gear just packs into a pocket or two and can be unobtrusively whipped out to complement your birding from time to time.