Hot answers tagged optics
Why do light sources appear as stars sometimes? Taking a night shot with light sources involved, the sensor goes nearly always into saturation. This is because the dynamic range of the motif is much larger than the one of the camera. People are normally interested in the "illuminated darkness" rather than in the light sources. From the photographer's ...
It's only the image circle that changes, really. Everything else either remains the same or becomes a bigger problem (for instance, the need for even wider apertures for the same depth of field at the same angle of view and subject distance means that greater degrees of correction will be required for things like coma, spherical and chromatic aberration). (A ...
I think the only possible answer to your question is "no such rule of thumb exists". The problem is just too complicated - as Matt indicates in a comment, how "distracting" the background is depends immensely on the content of the background, so you're first of all going to have to capture that. And if you can do that, you're pretty close to having reduced ...
I believe that you will find the answer to your questions under http://www.stfmc.de/misc/diffcontrarefl/tlf.html
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