Merge images to hdr – Adobe Photoshop CS4 User Manual
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USING PHOTOSHOP CS4
Opening and importing images
Last updated 1/10/2010
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The exposure differences between the photos should be one or two EV (exposure value) steps apart (equivalent to
about one or two f-stops apart).
•
Don’t vary the lighting; for instance, don’t use a flash in one exposure but not the next.
•
Make sure that nothing is moving in the scene. Exposure Merge works only with differently exposed images of the
identical scene.
Merge images to HDR
Use the Merge To HDR command to combine multiple images (with different exposures) of the same image or scene,
capturing the dynamic range of a scene in a single HDR image. You can choose to save the merged image as a 32-bpc
HDR image.
Note: It’s also possible to use the Merge To HDR command to save the merged image as an 8- or 16-bpc image. However,
only a 32-bpc image can store all the HDR image data; 8- and 16-bpc images will be clipped.
HDR merging works best when photos have been optimized for the process. For more information, see “
1
Do one of the following:
•
(Photoshop) Choose File
> Automate > Merge To HDR.
•
(Bridge) Select the images you want to use and choose Tools > Photoshop
> Merge To HDR. Skip to step
3.
2
In the Merge To HDR dialog box, click Browse, browse to select the images, and click Open.
To remove an item, select it in the Merge To HDR dialog box and click Remove.
Note: If you want to add a folder of images or images that are open in Photoshop, choose Folder or Open Files from the
Use menu.
3
(Optional) Select the Attempt To Automatically Align Source Images option if you held the camera in your hands
when you photographed the multiple images.
4
Click OK.
A second Merge To HDR dialog box displays thumbnails of the images being used in the merged result, a preview of
the merged result, a Bit Depth menu, and a slider for setting the white point preview.
5
If necessary, do one of the following to set the view options for the merged result preview:
•
Click the Minus or Plus buttons below the preview image to zoom out or zoom in.
•
Choose a view percentage or mode from the pop-up menu below the preview image.
6
Choose a bit depth for the merged image from the Bit Depth menu.
Be sure to choose 32 Bits/Channel if you want the merged image to store the entire dynamic range data of the HDR
image. 8-bits and (non-floating point) 16-bpc images files cannot store the entire range of luminance values in an HDR
image.
7
Move the slider below the histogram to preview the merged image.
Moving the slider adjusts the image preview only. All the HDR image data remains intact in the merged image file. If
you’re saving the merged image as 32-bpc, the preview adjustment is stored in the HDR image file and applied
whenever the file is opened in Photoshop. The preview adjustment is always accessible and adjustable by choosing
View
> 32-Bit Preview Options.
8
Click OK to create the merged image.