photo of Sami Serola

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Posts tagged with "hdr"

Fake HDR or not to fake

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Android Camera 360 software used with HDR (heavy) effect Basic editing with level and curve tools Fake HDR Look in Gimp
HDR images have been a hot topic lately. A real High Dynamic Range (HDR) image is made out of multiple images taken with EV bracketing. In other words at least three pictures are taken with exposure values -1.5, zero and +1.5. So, one picture is underexposed, one normal and one overexposed. Then on editing software, using some tricky procedure, these pictures are combined to get one picture where's high dynamic range aka enough light and tones also in dark areas.

Another, much older method, is to use negative image as filter. In short the method consist of B/W inverse, transparent (negative) layer that is used as a filter to bring tones into very light and dark areas. In very same this could be used during the film era when projecting and printing on paper. Negative film was duplicated into positive dia slide and then they were put into enlarger.

What I now found was a little more complex procedure to use the method on GIMP photo editing software. And it seem to work just fine. I suppose the method used for example in various Android software, like PicsayPro and Camera 360, gives somewhat similar fake HDR results.

EDIT: And then I found much more simple way and very similar as I once discussed with Mad Scientist. A Geek in the hills has added very important addition to the instructions. Here's those instructions modified by me:
  1. Colors->Levels->Auto if it seem to improve, cancel if not. Alternatively just adjust brightness and contrast.
  2. Duplicate the base layer.
  3. Image->Adjustments->Desaturate second layer
  4. Image->Adjustments->Invert second layer.
  5. Set the second layer to soft light.
  6. Add a ~50* pixel Gaussian blur on the second layer.
I was surprised to see how much the Gaussian blur affects on the results.

*EDIT: It is very important to experiment the amount of Gaussian blur! On some pictures much less blur is better. Thanks to Kelisha I just found out there's such thing as 'Tool > GEGL Operation', which you can use to apply Gaussian blur in much more convenient way. That way you see how the Gaussian blur affects on the whole picture, not just the current layer.

HDR images that look less like HDR images

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I became interested in HDR photography. There are at least three ways to do it: 1) Using three or more photos exposed with different setting (e.g. EV -1,0,+1) and combine them to get the best areas of each photo selected and stitched together, 2) Using one RAW 14-bit image that can be taken with latest sensors on market, or 3) Doing so called fake HDR pictures using only one shot.

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