Underexposed

[tigerphoto]

I took a couple of pics of my friend and all of the pics came out underexposed. How can I fix them? Feel free to give examples.

[RokcetScientist]

Originally Posted by tigerphoto

I took a couple of pics of my friend and all of the pics came out underexposed. How can I fix them? Feel free to give examples.

Depends on your definition of 'fix', tiger. Because you can do all sorts of things to that image, but it'll look 'arty', or 'creative', or 'special'. Maybe even beautiful. Or of course just plain rubbish. But it'll never get the quality of light the photographer seems to have had in mind.

That's why these sessions should be shot 1) in RAW, 2) in bracketed exposure sequences, and 3) checked onsite (on a laptop screen, not a 2 incher). And, obviously, with buckets of light!

[mistermonday]

There are many ways to correct underexposed images. In Photoshop CS or CS2, the Image>Adjust>Shadow Highlight works very well for these images. You can also use Image > Adjust> Levels and pull the Highlight slider over. There are also Curves adjustments if you fell comfortable with Curves.
On your orig image all work to produce the same result as shown below. I increased the brightness, raised the saturation a little, and ran a noise filter on the image to reduce the color noise.
Regards, Murray

[sylvia1065]

Hi Tiger,
A very quick trick: duplicate the layer, set the blend mode on screen and adjust.
Sylvia

[tigerphoto]

Rokcet: What so hot about RAW and what is a bracketed sequence?

Mr. Monday: What about in PS7

Sylvia: Blend mode?

[sylvia1065]

You have to open the layers palette (Window, Layers), click on Normal and scroll down to "screen".
If your photo is overexposed, use the "multiply" mode instead.
Hope this helps!
Sylvia

[tigerphoto]

Thanks sylvia. Second question why does the pic look a little pixelated when I do this?

[Daviskw]

Hi

I know in my underexposed pictures I often have noise in the shadows. It is not always noticeable until the tone is adjusted. Sometimes you will need to run a filter of some kind to reduce the noise.

Or even apply a little gaussian blur followed by a little noise.. say 1.5 pixels . The blur tends to reduce the noise from underexposure and the 1.5 pixels of noise will bring back apparent detail.



Butch

[Tpage]

If you underexpose like this AND shoot jpeg you are asking for trouble. Jpeg will throw away information that RAW keeps which would allow you to save this image. To see just how much colour information has been lost convert the image to LAB color mode in photoshop and then look at the a and b channels. See how pixellated they are? That's down to the jpeg compression.

With digital it pays to 'expose to the right' and shoot RAW i.e. turn on the histogram in review mode if your camera has one and make sure that the histogram is as far to the right as possible without overexposing.

Most digital sensors use 12 bit colour internally which gives 4096 levels or tonal values for each pixel. You'd think that an underexposure such that only the left 60% of the histogram has any appreciable data would give you 60% of the 4096 values right? (like in your image above)

WRONG. Assume there a 5 stops worth of light in the scene (a reasonable assumption) Every stop of light down means half the amount of light than before ... The above underexposed image is only using about 3 stops worth of light so it is throwing away 2 stops worth of information. Meaning that only 1024 of the 4096 tonal levels are being used.

Because the number of levels being used is reduced, this will introduce colour noise into the image particularly in the darker areas. Trying to bring these levels up will amplify the noise as you have seen when using a duplicate layer set to screen mode as suggested by sylvia.

By shooting in RAW and exposing to the right, you will probably need to darken the image in PS afterwards. You can do this by duplicating the layer and setting the mode to multiply in PS. This has the added benefit of REDUCING colour noise.

The shot supplied will never be as good as a properly exposed image. If you want to do it right you'll have to start again.

[RokcetScientist]

Originally Posted by tigerphoto

Rokcet: What so hot about RAW and what is a bracketed sequence?

RAW allows you to adjust exposure settings, white balance, etc., after you've pressed the shutter, in the post production/editing phase. Plus what Tpage says.
Bracketed sequence: you depress the shutter once and the camera shoots a sequence of 3, 5, or more frames at, for instance, half f-stop increments (depending on your preset). Many cameras have this feature. Look at your user manual under 'bracket' to see if yours does too.

It still would'nt have been enough with this photo, though. Imo this one needs 3 or 4 times as much light!

[Flora]

Hi,

Originally Posted by tigerphoto

What about in PS7

In PS7 you can duplicate the background, set the dupe's blending to Screen, duplicate the Screen Layer and adjust it's Opacity ...

Neat Image to minimize the noise in the 'shadows' ...

[PhotoVagrant]

Retouched using 2 actions from 1 Click Actions. First "IncreaseExposure" action and then "PopGlow"

[slipchuck]

I used curves eye drop method..... used the white eye drop for the whitest part of the swim suite, black sample from her hair.
grey sample was done this way.....
creat a new layer, fill it with 50% grey.
make sure this is the top layer (over the image in question)
change the blending mode from normal to difference.
now make an adjustment layer, choosing threshold.
when the threshold box open, move the right slider all the way to the left, untill everything is white.
slowly move the slider right until the first indication of black appears.
with the eye dropper tool, hold down the shift button and click in one of those first black pixels.
once this is done, press cancel to the threshold layer, and then delete the new layer (the one filled with grey)
now open up the curves dialog box, select the middle eye dropper (for greys)
with the middles eye dropper, click inside of the sample you took when you shift clicked one of the black pixels as descriped above.
once this is done, select the eye dropper tool and select the color sample eye dropper tools out of the options.
a "clear" buttons appears near near the top at the left.

hope this helps your needs

slipchuck

[sylvia1065]

Tiger,
After you duplicate your layer and set it on screen, merge your 2 layers, duplicate again, set the mode on "color", run Median (Filter, Noise) and try different values (I tried 12 on your picture and it worked nicely).
This won't remove all the stray pixels though, just the weird colors that show after.
Hope this helps a bit,
Sylvia

[manta1900]

With respect to the original colors (and to the beauty you saw)...