Orion 52084 instruction manual Flat Fields

Figure 13. A dark frame contains the background noise. The same background noise appears in your “light” images. Dark frames isolate the noise so it can later be subtracted from your “light” images.

3.Choose Autosave in the box beneath the Mode box.

4.Set the number of dark frames you would like the camera to take under Autosave (3 to 10 will generally suffice, as these will be averaged together)

5.Select the file folder in which you would like to save the dark frames with Folder, and enter in a Basefilename for the captured dark frames. Typically the name of the object being imaged with the word “dark” added, such as “OrionNebula1dark”, will be entered here. If “OrionNebula1dark” is the Base filename, and you choose to Autosave five images, then the images will appear in the selected file folder as “OrionNebula1dark_0001. fit”, “OrionNebula1dark_0002.fit”, “OrionNebula1dark_0003.fit”, “OrionNebula1dark_0004.fit”, and “OrionNebula1dark_0005.fit”. Using the word “dark” in the Base filename will help you distinguish between light and dark frames when combining later.

6.Click Expose, and Maxim DL Essentials will indicate the camera needs to be covered to take a dark frame. Cover the front of the telescope you are imaging through, and then click OK. The camera will commence taking and saving the dark frames. You will calibrate your images with these dark frames later see “Dark Frame Calibration”.

Flat Fields

A flat field is an image taken with uniform featureless light entering the tele- scope, such as a blue sky in the early morning or after sunset. Flat fields solve a number of issues in your astro-images.

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