Don’t throw that picture away yet!

Posted: 7th January 2010 by Jacky Yong in Computers, Photography
Tags: , ,

How many of you remember taking a photo, only to find out that the photo turned out bad due to incorrect exposure? (It could be due to underexpose (picture turning out too dark) or overexpose (picture turning too bright).) Even though in the world of digital photography where the camera decides everything for you, things can still get very wrong. And most of the times you have no choice but to press that delete button.

Things gets worse when you find out that the photo is a very important photo that you absolutely must keep. So how can you save it? I have personally seen a lot of people successfully saving their bad pictures digitally, but they were damn fucking stingy. They did not want to share their techniques to the world. Hate these fuckers.

Luckily a bit of Uncle Google and some photoshop experience helped me to figure it out. Take a look at this picture below:



Exposure skewed

Incorrect exposure, making the foreground dark and the background bright

That’s my little girl Hui Yan. You really can’t blame the camera. You can see that the bright background threw off the camera’s exposure metering calculation, which made Hui Yan’s face dark, and blew the background away. A really bad picture. If I saw this picture a few months back, I would have thrown it away. But I tried to salvage it. The cute expression on my girl’s face is just too previous to throw away just like that!

Traditionally I would increase the exposure setting for the foreground and decrease it for the background. But doing so made the contrast go awry, the effect was not very pleasant at all.

Uncle Google to the rescue! He told me that the way most people increase expose is to duplicate a layer of the original picture. Here’s the trick: change the blend mode from “Normal” to “Screen”. Then repeat the process, copy another layer from the last layer and change the blend mode to “Screen”. Do this as many times as necessary until you are satisfied with the level of exposure.

To decrease the exposure, do the same step, but this time use “Multiply” as the blend mode.

Needless to say, I used layer mask to blend in the brightened up foreground and the darkened background. Here is what I have got:



Correctly exposed!

The picture is correctly exposed, and Hui Yan's face is clearly visible!

What did I learn from this? There is one very important lesson from all this. And that is underexposing is much safer than overexposing. I used only 3 layers to brighten up the foreground, but more than 6 layers before I can properly darken the background. As you can see from the photo above, the details in the curtains are lost forever, and I can hardly bring back anything there. But the underexposed foreground is still save-able, albeit with a bit of a noise. But noise can always be taken care of right?