brightness vs. exposure
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- inkpink
i've always wondered;
when lightening a camera raw image, which is preferable and why... ?
- inkpink0
thx. guess i coulda googled that.
- inkpink0
happy to read exposure is generally superior.
- epic_rim0
def exposure
- Hombre_Lobo0
In my experience -
Exposure gives a much more natural way of brightening an image as it enhances already present light.
Whereas brightness (im guessing here), it looks like it just lightens every pixel individually which does not give as natural looking results as exposure.
- SteveJobs0
^ kind of, brightness is generally just a scalar multiplication, though it wouldn't surprise me if adobe's implementation is a bit more involved, or 'smarter' for the sake of minimizing over-exposed results.
- coolio, but still steve, where the fuck is flash on my iphone?Hombre_Lobo
- gooooood question.SteveJobs
- lol :PHombre_Lobo
- inkpink0
yes comments similar to what i had already assumed.
what's weird though is that i notice auto-adjustments in lightroom almost always change the brightness and contrast instead of exposure.
i know auto is unreliable and not the way to go, but i sometimes click and use feedback as a starting point.
- SteveJobs0
algorithmically, brightness/contrast are generally linear in nature so it's probably easier to calculate a good approximation adjustment for those as opposed to exposure.
who cares though. which ever gives you the best results for your image, right?
- bekannt0
yep exposure is the way to go.. but when the picture is good you dont need to do much tweaking..unless you are looking for some experimental looks... also recovery helps a lot to see some details where light is blowing up......
- vaxorcist0
Curves! not exposure, if you can.... why?
you may already know this.... why? 1-2-4-8-16-32-64-128-256-512-102... you get the idea, at the TOP of the numbers, the brights have alot more gradation, whereas at the bottom, in the shadows, there's not much gradation there, so you get these banded-out shadows too easily...
Due to the way digital images are stored, ideally it's better to slightly over-expose rather than under-expose, as long as you don't blitz the highlights....
If you're doing much exposure adjustment, try to make sure you're NOT in an 8 bit per color mode, try to have your file in a 16 bit per color mode, (depends on app, but NOT automatic)
- Hombre_Lobo0
@vaxorcist
its the other way around as sequoia pointed out.
its always better to have no blown highlights (within the areas of which you wish to retain detail) and underexpose - as its safer and more recoverable to boost shadow detail and lighting.whereas when its overexposed detail in blown highlights is irrecoverable (as its pure white pixels), much safer to go underexposed.
- lukus_W0
Isn't it preferable to adjust the levels / histogram curve manually? That way you make sure you don't clip anything.
- well, yeh, you use the histogram whilst taking a shot to help make sure the exposure is correct.Hombre_Lobo
- I think it's worth referring to the histogram throughout yr workflow - in all digital media, clipping is your enemy.lukus_W
- johnnnnyh0
Indeed, underexposure (even in film days) was always more recoverable since the image is there not wiped clean with clear/white pixels. I guess with digital there's a bit more flexibility but I would want to go darker rather than lighter in exposure terms. Better to get it "correct" though!
- lol indeed!
correct exposing first time is the win.Hombre_Lobo - expose to the right. there is more data on the right side of the histogram than on the left side.jaylarson
- it's easier going darker than it is to go lighter:
http://www.luminous-…jaylarson
- lol indeed!
- johnnnnyh0
Curves is probably best way to adjust and my understanding of brightness is that all pixels are adjusted in the same way to the same extent.
With curves you can stretch the middle and leave the extremes - which is the way I think they describe using it.
- Hombre_Lobo0
yeh curves i find give a natural result.