Orion 52084 instruction manual Recommended Processing Sequence

There are three elements which must be set: the Permanent Stretch Type, the Input Range, and the Output Range. You can use the Preview Image to see how changing these parameters will affect the resultant image (or click the Full Screen button to see the changes applied to your actual image). You can also open the Screen Stretch Window to see how changing these param- eters change the histogram.

For the Permanent Stretch Type, the Linear Only mode is useful for adjust- ing the range of pixels to match a particular file format. The Log mode is useful for compressing the dynamic range of the image, but can be rather harsh. The Gamma mode allows you to selectively emphasize bright or dim parts of the image by entering a suitable Gamma Value. A Gamma of 1 has no effect, less than 1 will emphasize faint details, while a value greater than 1 will emphasize bright details.

The Input Range can be set to Screen Stretch, which in Linear Mode pro- duces an output matching the current screen appearance. This is useful in producing final images for output to 8-bit image formats which have limited range. Note that the minimum and maximum values are always taken from the screen stretch settings for the original image. These can be adjusted dynami- cally using, for example, Quick Stretch. The Max Pixel selection sets the input range from 0 to the brightest pixel in the image. This prevents any image pixels from being saturated in the final result, but may produce images with low contrast. You can also manually set values with Manual Settings in a similar fashion to the Screen Stretch Window.

The Output Range is used when preparing a file to be saved in a format that has limited range. The Output Range maps minimum input to zero, and maxi- mum input to 255, 4095, or 65535 depending on the settings. Any values that exceed the limits are clipped. The Unlimited setting disables all limiting and is recommended when performing Gamma and Log stretches; it is appropriate when the image will be saved in floating point format.

Recommended Processing Sequence

What is the best order to apply the processing functions in? Here is a recom- mended sequence:

1.Calibrate (Dark Subtract and Flat Field calibrate)

2.Convert Raw to Color

3.Combine

4.Filter

5.Color Balance

6.Stretch

Once you have the combined image, you are free to continue processing the image as desired, or export it to a program like Photoshop. Be sure to Save a copy of the combined image; otherwise you might have to go back to the

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