Camera Focal point

[kenshinsano]

Hello everyone.

 

I am writing to you today to raise a question that raises serious concerns.

I'd like to highlight "a focal pointt" or an indicator allowing the user to check if the development that makes the camera (the result of what they filmed is displayed on front Panel program) is more or less good according to the filmed object.

I thought of gray level profiles and calculate the slope of the graph covering a black object and thus infer its sharpness but in vain.
 

While waiting for your valuable help, thank you in advance.

[Guillaume_H]

Hi,

Thank you for posting your question on National Instruments Forums.

One easy way to realize what you want to do would be to use a sight to focus your camera on.

For instance, if you place a black cross printed on a white paper next to your object, at the same distance from the camera, you should be able to focus your camera on this pattern. By making a pattern recognition sub-routine in your program, you should be able to find the pattern by adjusting the focus of your camera. Several pattern recognition programs can be made, especially if you are using our

Vision toolkit for LabVIEW.

Once you are focused on the sight, you should also be focused on your object.

I hope this information helps.

Best regards,

[Leeser]

This sounds like you are trying to autofocus. As Guillaume said you need a target object to look at like a cross or a chessboard.

By hand, capture an image get the standard deviationof the pixels, change the focus of the camera, capture the image, get the standand deviation ....

The best focus is at the point where the standard deviation of the pixel values is a maximum.

[kenshinsano]

Is it possible to have an example please ?