28 February 2015

Camera Trap Photo Tricks 101

I've been fairly busy wrapping up the development of the next WildLog version (should be out in March) and haven't had much spare time for blogging. I've been wanting to do some blog posts about the "post processing" I do on the camera trap photos I post on this blog. So I'll try to do 2-3 posts about it over the next few weeks, starting today :)

The sad truth is that even the best digital cameras can struggle to capture a natural scene in it's full glory and most commercial camera traps don't use anything close to the best (and most expensive) camera lenses / sensors.

My goal is to "restore" the photographs, to get them as close to the real life environment as possible. I try to get more natural colours, not "fake enhanced nature", but it can be tricky at times to find the balance. I don't use the rubber stamp, paint brush, smudge or any other fancy tool to "fake" or edit the images.

Below are some examples of what a few simple processing steps can do to improve your camera trap photographs. I've included a list of the steps taken in every example.

Long time readers might recognise some of the examples photos from earlier posts :)

Common Duiker (Gewone Duiker - Sylvicapra grimmia) at Koeberg Nature Reserve

Even though the After photograph looks much better than the Before, the colour of the animal is still peculiar. I try to only use tools that affect the entire image. Usually you have to find a balance between the real colours and the quirks of the camera hardware/software.

Over the years I've found that the "auto" tools in Photoshop do a decent job and I don't need any crazy technical knowledge or hours of time to get a decent result.

A few years back I was fortunate enough to get Photoshop Elements from the Adobe online store for a crazy good price (something like 75% off). I have found that the Photoshop Elements edition is much cheaper and more user friendly than the full product. The functionality it provides is more than enough for my needs. (For those on a budget, there are many decent free, or cheaper, alternatives out there.)

Small Grey Mongoose (Kleingrysmuishond - Galerella pulverulenta) at Berg River Dam

The auto colour and level correction tools are usually able to find a more natural colour balance, but the brightness and contrast tools can also make a big difference.

My usual approach is to darken the highlights slightly and (sometimes) lighten the shadows very slightly. Then play around with auto levels and colour until I get a decent result. The order in which you apply the steps can sometimes make a huge difference (and can be different every time).

Caracal (Rooikat - Caracal caracal) at Tygerberg Nature Reserve

Be careful not to overdo the effects, especially when playing around with the shadows/highlights. The presence of shadows and highlights add to the overall image and overdoing it can make the image look awkward and unnatural. I hope I strike a good balance myself!

The photograph of the Caracal above is a good example where the grass might look more "fake green" in the after photo, but the fresh spring grass at Tygerberg really do look very bright green in real life, not that strange yellow green in the original photo.

The "after" image in the below example takes the adjustments a bit further that I would usually do, but it illustrates just how much of the natural colour can be recovered through post processing.

Small Grey Mongoose at Tygerberg Nature Reserve

Unfortunately, no matter how hard you try some images just can't be saved. If there is no colour information present in the saved pixels to work with, then there is nothing any photo editing tool can do.

Usually you can still recover from severely under exposed photos, because there is a greater likelihood of some colour information still being present in the very dark shades, but recovering from over exposed photos are mush harder, since most of the pixels will be pure white.

Helmeted Guineafowl (Tarentaal - Numida meleagris) at Koeberg Nature Reserve

Interestingly enough the IR (InfraRed) flash cameras can produce some unexpected colours at night. I think it is due to the extent to which some materials reflect InfraRed light.

Above: Daytime photo from phone camera; Below: Nightime photo from IR camera trap

The change in perceived colour is most remarkable for the green and grey shirt at the top-right. The colours on the shoulders and the body almost seem to have swapped around! The dark navy blue shirt at the top-left also reflects very brightly in the infrared light and looks almost white.

I haven't noticed such a dramatic colour change in my real world camera trap photos, but I'm sure it happens to some extent.


  1. A very fascinating post. Although I have Adobe Photoshop Elements, I seldom use it. I have an even more basic program, Arcsoft Photostudio Expressions, (came with the camera that I bought). Mostly I only use the crop tool, brightness/contrast, and sometimes I increase color saturation slightly. It is much easier to use than Abode and greatly improves many of my photos.

    1. Glad to hear you enjoyed the post.
      I agree, the most important thing is to find a photo editing tool you are comfortable with and can handle the basics. I'm planning on doing a similar post about cropping, soon-ish.

  2. Hey Henry. Long time no chat. Interesting post - thanks very much. I found the IR colours particularly weird. Have you noticed this effect in any animals?

    1. No, I haven't noticed it yet. My gut-feeling is that maybe the odds of noticing the effect might be higher with reptiles, birds or plants (flowers) than mammals, or some creature that spends lots of time in the sun and needs to reflect some heat, but then they will, most likely, already be light coloured in general... It would be interesting to find a good example of this in nature, we should try to keep our eyes open ;)