Comment 3 for bug 696668

Implemented in changesets 9214f2ddb58b and 09790aafd95d.
For the geometric optimizer the limits are set now narrower.
The photometric optimizer does bake up results if the the vignetting is too high and/or the WB values are too high (maybe the limits needs some more fine tuning). It is also possible to add a check for the response curve. But what values for the response curve are considered invalid?