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Hello everyone,
I have an optical design with an effective focal length of 250 mm. However, after adding a Schmidt prism, the effective focal length becomes -0.106 mm, whereas it should be around -205 mm. Could you please help me with this issue?

Hi Baran

A prism with flat surfaces behind an objective should in principle not change the EFL. It will change the EFL however, if you put it somewhere within your objective. Can you make a simple drawing?

Regrads, Dusan


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