HDR

HDR
Presentation by Rosie Lemons 8/12/08
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Uses 2 images, one dark and the other light.
Copy and paste the darker one in the lighter image file in Photoshop.
Add a layer mask.
Copy the background layer [Click on the background layer on the palette and the press CTRL-A to select the whole image. Press CTRL-C]
Now hold down the ALT key (Option on the Mac) and click on the white mask rectangle on the dark layer.
Next, press CTRL-V to paste onto the white mask. You will now see a B&W image of the background layer.
With the B&W mask displayed go to Filter / Blur / Gaussian Blur and set the Radius to about 10 - 40 pixels. [the radius depends upon your file size. With large files, use 40. In here, the images are small for quicker loading so try using 10]
Click on the Background Layer and you're done.
You may want to add an adjustment layer to ‘perk’ the image up a bit.

Requires 3 images, one ‘normal, one over exposed, and one under exposed.
Copy and paste them into one Photoshop file with Normal on bottom and Over on top.
Select the Over layer and add a layer mask by opening the Layer> Add Layer Mask menu and selecting Reveal All.
Open the Image menu and select Apply Image. In the Apply Image window, checkmark Invert and click OK.
Select the Under layer and add a layer mask by opening the Layer> Add Layer Mask menu and selecting Reveal All.
Open the Image menu and select Apply Image. In the Apply Image window, select the layer Under, uncheck Invert, and then click OK.
Again, you may want to add an adjustment layer to make the image POP

You can get away with some processing on a single RAW file. In fact you can easily push RAW files to +/- 2 f-stops in post processing (that would be equivalent to taking 5 images each one stop apart).
Open up a RAW file and play around with the exposure slider. Move it to the left and see the image become darker. Watch your highlights and see how much information we can recover. Find out how low you need to go (but don't go much beyond 2 f-stops).
Do the same with the Shadows by going the other way. Note upper and lower exposure numbers and divide the range by 3 – 5.
Enter these numbers into the Exposure compensation box and convert one image for each (3-5 images in the first example.
You can now use these images either in the Merge to HDR in Photoshop or by using the Photomatix program.