Correcting for underexposure

rjmiz · #1 (**permalink**) 03-17-2007, 07:12 PM

Recently someone asked be how to prevent blown out highlights. Especially if your shooting INTO Sunlight. I really don't have a right or wrong answer, but I told hime what I do: I expose for the Sun.

The reason being I don't want blown highlights. Once the highlights are blown out, all information is lost and CAN NOT be recovered. I can however, recover information in an image that is UNDER EXPOSED.

So here is a RAW image taken with my camera. The image below that is processed in photoshop to recover the underexposed information in the lighthouse. I will not go into details, but my method involves the extensive use of masking, and blending.

Now, I realize that I have just about added an entirely new sky, howver I also have a third version with the original sky that is not blown out because I exposed for the sky, rather than the building.

In this age of digital imaging, some of the film techniques for handling this situation, are unnecessary when you use photoshop.

Any questions?

photobunny · #2 (**permalink**) 03-17-2007, 09:22 PM

Nice images

Im not sure if I would want to underexpose and then manipulate in photoshop to get a correctly exposed image, Im always a bit nervous with photoshop lol. Wouldnt it be easier to try and experiment with metering patterns and bracket exposures in-camera?

Gracey · #3 (**permalink**) 03-17-2007, 10:47 PM

Or you can expose once for the sun and once for object (use a tripod) and do a combined photo - two's not really enough for hdr. Or you can buy a lightmeter and expose properly in the first place.

Yes, very nice after image; maybe a touch more light on the building though - something warm like the ligth from a setting sun. You can do that robert, I know you can.

rjmiz · #4 (**permalink**) 03-17-2007, 11:48 PM

I think you may be correct Gracey....I played with it
It is after all a shot taken at Sunset, so It is a bit darker.

thesupe87 · #5 (**permalink**) 03-26-2007, 09:35 PM

That looks great. Man, I need a cam that shoots RAW! So much more control.

mangia · #6 (**permalink**) 03-29-2007, 12:41 AM

This image is born for HDR

maybe you should try it..

Anyway it is excellent...

Sam · #7 (**permalink**) 04-09-2007, 06:03 PM

it depends on how underexposed the shot is and how complexity the image. Photoshop could help you if shot in raw, you can use the shadow tool, curves and levels to lighten or darken the image you want.

Fotosmurf · #8 (**permalink**) 04-11-2007, 10:31 AM

How do you prevent additional noise creeping in if you underexpose so heavily? I also shoot raw but even then when I have something that is seriously underexposed (and my 20D is horrible in underexposure) and I change the settings I do get additional noise in almost any part. I use Rawshooter for raw conversion... not sure if that makes the difference, but how do you avoid it from happening??