Geoptik Flat Field generator for OTA 250-308 mm

Geoptik Flat Field generator for OTA 250-308 mm (outer diameter of the optical tube or the dewshield)

Image calibration is a very important first step in the processing of an astronomical image. Light Frames are images (or a video) of a celestial object captured by the CCD. Each pixel in the images will have a numeric value that includes the influences of:

• Light from the celestial objects in the field of view.
• The various types of noise generated by the CCD.
• Defects in the optical system.
• CCD inhomogeneities (pixels more or less sensitive to light)
• Optical vignetting (image is darker away from the centre)
• Dust on the CCD window (seen as 'donut' shaped spots on the image)
• Internal reflections

With calibration we will try to remove as much as possible of the Bias and Dark Current from each Light Frame. Also, we will try to remove the effects of certain types of optical defect.

It has a rheostat for adjusting the light intensity. Cigarette lighter cable included.

With its three plastic screws you can fix to telescopes with diameters from 250 to 308 mm