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Gem
07-23-2010, 12:36 AM
I was wondering how to properly expose for backlit subjects, while not blowing out the background?

Here was the situation I was faced with last weekend: in Banff, we (my bro, his wife and I) were at a lookout point, overlooking Lake Louise and the Fairmont. The lookout was shaded, and it was a fairly sunny day. I was taking a picture of my brother and his wife with the view behind them, and thought the flash would brighten them up - it didn't :shrug: And, I wasn't exactly sure what else to try. I'm heading to Jasper for the long weekend, and I would like to have a better result than last time :/

Suggestions, anyone? Looking back, all I can think of was to take a picture exposed for the background, then another exposed for my brother and his wife, then blend together on Photoshop?

Richard
07-23-2010, 03:24 AM
Hi Gem,

In full manual, you should be able to switch to spot metering and take an exposure reading for the sky. Your TTL flash should then act as a fill flash properly exposing the foreground. Failing that if you can always use the flash compensation feature to balance your flash exposure with the natural light.

If your flash had no effect on the picture it's possible you were to far from the subject for it to be effective?

Wicked Dark
07-23-2010, 07:42 AM
Spot metering and fill flash will help as Rich says, but the 'without blowing out the background' in your original post is the kicker. It depends on the total # of stops in the scene and the # that separate proper exposure of the subject from the bg. A digital camera can handle about 10 stops without clipping, if there's more than that between the subject and any part of the bg, that part will be clipped. Sometimes you just have to live with it or try to reframe the subject to eliminate as much of the bg as possible.

Iguanasan
07-23-2010, 08:04 AM
Good advice so far. My flash skills suck but might I suggest you poke around in your camera's manual as it may have a suggestion.

Mad Aussie
07-23-2010, 05:49 PM
Yep the advice so far is very good.

Gem ... I'm assuming you have the built in flash only. These definitely are only for short range so therefore you need to be closer to your subjects.

Here's what I'd try in this situation ...

Firstly, take the background scene and get that the way you want.
Then bring in your subjects and use the flash to fill. In your menu you should have a flash exposure setting that allows you to increase the flash strength.
Also remember that later in PP you have a certain amount of control so settings with a slightly higher ISO or aperture that allow the flash to fill the faces, and slightly create a background that's a bit light, will probably be savable later.

Also, don't forget the good old reflector. A nice white reflector of some sort will help.

casil403
07-23-2010, 07:50 PM
I have tried in this case to switch over to autobracketing, take 3 or 5 shots in a row and then run it through an HDR program like Photomatrix. I then try to make it look as non-HDR as possible and have been quite successful with the technique so far. a few tweaks in LR and it is almost indiscernible that it is and HDR image.
Takes a while to do but it has worked for me on more than one occasion.
Might not be the best answer out there but it works for me so try it if you like. :)

Gem
07-24-2010, 02:31 PM
I can't imagine I was standing too far away - I'm sure it was no more than ten feet! But, I never checked the flash strength, so I'll have to remember that - and also spot metering.

Casil, I'm definitely going to give that a try!

Thanks all :)

Mad Aussie
07-24-2010, 03:26 PM
I can't imagine I was standing too far away - I'm sure it was no more than ten feet!
On a dark night ten feet would be fine of course ... but go outside in the middle of the day when you and your camera has metered for the brightness of the sky and therefore is set to be less sensitive to light, and suddenly your little flash may struggle.

Marko
07-27-2010, 11:51 AM
Spot metering and fill flash will help as Rich says, but the 'without blowing out the background' in your original post is the kicker. It depends on the total # of stops in the scene and the # that separate proper exposure of the subject from the bg. A digital camera can handle about 10 stops without clipping, if there's more than that between the subject and any part of the bg, that part will be clipped. Sometimes you just have to live with it or try to reframe the subject to eliminate as much of the bg as possible.I agree with about half of this quote

It depends on the total # of stops in the scene and the # that separate proper exposure of the subject from the bg.
100% correct. If the range between bright and dark is too great, it simply cannot be captured in one file. You will lose either some highlights or some shadows. You'll need to use multiple files at different exposures to get all of the detail, as casil mentioned.

Personally i would not do this though.... I would do the following;
Shoot the scene with fill flash. If the background is too dark increase the CAMERA's exposure only. If it's too light, do the reverse.

If the people are too dark increase the flash exposure only (+1, +2, etc.) or if they are too bright do the reverse.

This can easily be accomplished with any newish on/off camera dedicated TTL flash. It cannot always be accomplished easily with the dinky popup flash on many cameras.

A digital camera can handle about 10 stops without clipping, if there's more than that between the subject and any part of the bg, that part will be clipped.
This has not been my experience, though I read this a lot. There's lots of technical stuff that go into this statement, but practically speaking i see less dynamic range overall in my DSLR when i compare it to my film camera.
This is why many people dig HDR imo, it compensates for the reduced range. (I should say that things change fast in this regard so if anyone can prove to me that this opinion of mine is outdated, I'd love to see some text with pics - not pages of 'photogeek text' with no images ;) )

I find I always need to underexpose an image that is close to the 8-10 stop range....and ya know what, i do believe i will go out and do a specific test on this with an excellent Minolta spotmeter that I still love.

Hope that makes sense - Marko

Gem
07-28-2010, 12:43 AM
Noted, MA. Didn't think of it like that, thanks :)

Marko, thanks for the pointers. I think I'll give it a shot sometime before I head out for the weekend, and see how it goes. :fingerscr

Marko
07-28-2010, 10:24 AM
....

Marko, thanks for the pointers. I think I'll give it a shot sometime before I head out for the weekend, and see how it goes. :fingerscr

no prob. you totally SHOULD. It's a setup you can use again and again and again...but with a portable on or off camera flash, not the popup. It's way too weak in many cases. A good flash is a key photo investment.