Wednesday, February 16, 2011

HDR Without The HDR

HDR (High Dynamic Range) is the hot thing to do with shot this (and last) year.  But, like many things we can do "easily" today by pushing a buttom, "HDR" could be done before actual HDR programs and plug-ins came out.  Today's image recreates an image with the expanded tonal range of HDR using a series of Masks, Alpha Channels and Blend Modes.  The original image was bright in the case areas and pretty dark in the wood sections.  The bags of jerky on the right side (the red bags) and the bottles stacked on the floor were in deep shadow due to the falloff from the light source (the lit cases).  The wood is broken into two areas that were treated separately.  The floor and the ceiling above the rear case.  There was very little detail in the planks on the floor and even less on the higher wood.  There were ancillary problems that needed some attention because of the wide angle shot.  The floor at the rear and the top of the rear cases showed some convergence and the frames of the cases along the left side needed a little straightening.  That's not what today's post is about, not I may revisit that in another post.  Today it's more about getting an HDR look without using HDR software.  To find out what went into today's image, hit the "read more".
A couple Alpha Channel Masks were made using the Quick Selection Tool (W) and the Polygonal Lasso Tool (L). The first was the floor. The QST couldn't pick up the edges of the soda boxes compared to the edges of the individual boards. The PLT was used to straighten out the errors. If the mistake was too deep into the soda case the Alt key was added to the use of the PLT to subtract areas from the selection. If more of the floor needed to be added to the selection the Shift key was used to add to the selection. Once the Selection was made a right click of the mouse brought up the context sensitive menu and Save Selection was clicked. This created an Alpha Channel. The area by the ceiling was selected using only the Polygonal Lasso Tool (L) and again saved as another Alpha Channel. The final area is the red bags and two liter bottles below the bags on the right side. This was selected using only the Quick Selection Tool (W). Any pieces needing to be added used the Shift key and anything needing to be taken away used the Alt key.

The sequence of action was similar in each case. Make a copy on the original Layer (Ctrl J), change the Blend Mode to Screen, Ctrl click on the Alpha Channel icon in the Channels Panel and hit the Create New Layer Mask found at the bottom of the Layers Panel. The floor required one copy of the new Layer, The ceiling needed two copies of its new Layer copy and the red bags needed four or five copies of the new Layer copy. Therefore the stack had: the background Layer, one masked copy with a screen Blend Mode, two masked copies with the Blend Mode changed to Screen and four copies with masks and Screen Bland Modes. So, we wound up with eight exact copies of the original Layer.

Once that was done a very slight vignette was applied (20% Opacity). I looked at sharpening the image, but that was too glaring. Selective sharpening could have been applied to some small areas, but the net result probably would not have been worth the effort. So, there you go, an HDR effect without using HDR software.

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