Vasyl Shynkar - 2024-12-08

Dear Frans van den Bergh,
Thank you for creating this wonderful tool, MTF Mapper. I would like to use it to test the lenses of my camera. For this purpose, I need to adapt the field of view to be approximately 13 times smaller than the A4 format and to have a different aspect ratio. Additionally, there are cases where the field of view is not rectangular but circular or oval.
At the moment, I don't fully understand all the details about how the code functions. I have a few questions:
Should the chart fill the entire field of view?
Is it necessary for the entire chart to be visible for calculations?
Can parts of the chart be cropped by the camera's optics and still be usable for calculations?
I am also curious about how the chart can be modified. I’ve read that the trapezoids should be oriented at an angle to the vertical and horizontal axes for the slanted-edge MTF calculation method. What about the trapezoids that are centrally oriented horizontally or vertically? Are these used for MTF calculations as well?
You mentioned that the sides of the trapezoids should be about 60 pixels. Is this a strict requirement for proper MTF calculation? I would appreciate more details about this condition, as I plan to significantly reduce the chart size, and my optics will further reduce it by a factor of 5.
Thank you in advance for your help with the chart generation issue.
Best regards,
Vasyl Shynkar