Monday, August 23, 2010

Professional Photo Enhancement

After spending most of my academic and professional career in the world of image and photograph processing, I became obsessed with improving the quality of photographs via a set of enhancement techniques. The result is that I literally get upset whenever I look at a friend's photos that were taken using a digital camera. I always point out the fact that if those photos get enhanced they will look so much better - I will repeat that over and over again if the photo has already been framed! Photo enhancement, or re-touching, makes a world of difference.

I also get nervous whenever I hear the prices that professional photographers ask to lend their services. Yes, some professional photographers are true artists, but those usually work for magazines and don't need to take on gigs like your wedding (unless they're starving - they may be starving artists!). Asking for $2,000, $5000, or even $10,000 for a day's worth of picture taking is, in all honestly, utterly ridiculous!

In my opinion, what makes the biggest difference between the pictures you take using your $200 digital camera - or even better an SLR camera - and the ones a professional photographer would take, is the post-processing. In other words, the photo enhancement that is done after the picture is taken is what makes it look 'professional'. In fact, a significant amount of work that professional photographers do is re-touch (enhance) their photographs.

Now, it is true that some photos can't get that much better, with the biggest problem being that they are taken under low-light conditions (e.g. during the night). Then, noise really becomes an issue when trying to enhance them. The only way to improve those photos is to use a camera with a larger area-per-pixel specification (more expensive), for example, an SLR camera. In Digital Camera Advice I explain how you can get better low-light performance without paying extra (in fact you may be paying less) and without sacrificing image quality. Nevertheless, the vast majority of digital photos that are out there are not taken under low-light conditions so you can probably do without paying the extra cash.

We all have digital photographs that we wish were taken by a professional. Those are the ones that bring up precious memories, people, and places. It may even be an image you uploaded to your website, your facebook page, or, alas, the photo you used for your online dating service profile.

You don't have to have a Ph.D. to make your photographs look like they were taken by a pro. You can enhance your photos by simply following the instructions that I include in this blog. Those can be found in Instructions to Enhance your Photos. You can use any of the free Photo Editors (no installation or registration required) that I mention in Free Photo Editors. You'll see that it's amazing what a difference a few simple steps make!

Friday, August 20, 2010

What Gets Enhanced?

In general, to make a digital photograph appear in a more pleasing way to the eye we should enhance the following: 
Illumination
Color
Resolution-Detail

Each of the enhancement solutions that I present targets one of these three categories, which I discuss next:

Illumination enhancement is meant to adjust the image brightness and contrast. The simplest way to do this is by adjusting the brightness and contrast levels for the entire image (global enhancement). Nevertheless, more impressive results can be achieved if local adjustment is applied.

Color enhancement is meant to adjust the saturation of the colors (color brightness) or the color hue. Usually, the latter is more difficult to do since digital cameras are affected by the sensor characteristics as well as the illumination under which a digital photo was taken.

Resolution-Detail enhancement is meant to sharpen the details in an image. In many cases it may seem that resolution is created after enhancement is applied - of course, this is not true since we can only enhance what is already there. It is noted that some use the terms 'resolution' and 'size' of image interchangeably but this is a mistake since a 1000x1000 image may contain less detail than a 100x100 image.

Noise considerations:
Ideally, one would like to enhance all of the three aforementioned categories without increasing noise. Even better, noise reduction can be applied if necessary. Noise reduction can be a complicated process since the type of noise that affects the image can widely vary.

To summarize:
Easy to enhance:
       Global brightness and contrast
       Color saturation
       Resolution-Detail
Tricky to enhance:
       Local brightness and contrast
       Hue
       Noise (removal)

The photos that I show on this page are shots I took using a $140 point-and-shoot digital camera that I bought back in 2007. The original and the enhanced version of each photo is shown to illustrate how this can also work for your photos.

You can follow the instructions to enhance your photos to do the same using one of the Free Photo Editors and you can do it quickly since no software installation or registration is required. 

Before and After Enhancement

Before and After Enhancement

Before and After Enhancement

Before and After Enhancement

Before and After Enhancement