Substitute a polarizing filter with image processing

More often i get the question why should i use filters in times of digital image processing. You probably heard of that a so called haze filter is needless. Concerning the graduated ND filters i showed in my article (sorry german only) that these filters can be substituted by means of image processing.

Introduction

A polarizing filter is used mainly for 2 purposes, once to elimante disturbing reflexions on water or glass. and to increase the blue colored sky in andscape photography.

Eliminating reflexions is not possible afterwards in image processing, but what about the effect of darken the sky ? This should be possible with image processing like Lightroom or Photoshop.

Comparism

As you can see in the example images i shot the scenery within a couple of minutes once without and with a polarizing filter.

I use a Hoya Pro Digital polarizing filter, but i guess there are no differences between other well respected manufactures.

Both example shots were taken with a Canon 5D MK II and a focal length of 28mm. By the way, because the polarizing effect depends on the angle to the sun (the greatest effect should be arround 90°), if you take an extreme wide angle lens, like a 17mm the effect will turn out uneven in the image do to the extreme wide angle. Depending on the scene it sometimes works out, but also can spoil your shot.

Image processing

From the above example we take as an information that contrast is increased and the color of the sky seems to be cooler.

A played arround with different settings in Lightroom and here is the result:

The color of the sky won’t match exactly to the shot taken with the polarizing filter, but it shows what ou can get out of image processing. To get almost the same impression like a polarizing filter image the contrast was increased and a played arround with the HSL controls.

The settings i applied were taken into a develop presets which is available for download.

To compare sharpness with an without filter i made a 100% crop and there are no significant differences in sharpness and resolution, so there is no reason to do every shot without a polarizing filter.

Conclusion

In landscape photography a polarizing filter can be substitued with image processing, so do you think about buying one?

Just leave me your comments/suggestions and questions if you like. I you liked the article i’ll be happy about a +1, like or Twitter share.

ciao tuxoche