Flattener

• Field Flattener

Flatteners are mainly used in astrophotography to correct the entire image field of refractors (refracting telescopes) better or completely.

Depending on the optical design and the amount of correction required, refractors are subject to imaging errors that can very quickly appear in photographs as blown-up (blurred) star images not far from the center of the image field. They are caused by a curved image field and here the so-called field flattening lenses ensure a smooth, flattened image with pinpoint star images right into the corners of the image field to be illuminated.

Please note that an image field flattener must be precisely calculated for the respective telescope in order to achieve optimum results. The optical effort is at least as high, if not higher, than for the actual main optics.

So now you know what you can expect from so-called "universal" field flatteners.

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