determining the working distance

[rpr]

Can someone tell me the exact relation between working distance and field of view?

[BruceAmmons]

The basic relationship is lens focal length / sensor size = working distance / FOV.

There is a lens equation that is a little more precise, but it usually isn't worth using it.

Is this what you are looking for?

Bruce

[Robert_Eastlund]

You can also use the calculator located at http://www.graftek.com/lensselect.php.

[muks · Accepted solution]

What bruce suggested is right.In addition it also depends on your application and the resolution you are looking at.You can view your ROI with 6mm lens as well as 35mm lens by increasing the working distance.So there are lot of factors determining the relation including your system compactness.

Are you having problem determining the best working distance for your application?Are you having problem with selecting apprpriate lens?

[rpr]

Yup muks that is exactly my problem.I can do the same task with a 25mm lens as well as a 35mm lens.How do you arrive at what is appropriate?

How do you rate answers.I dont see any ratings in the right bottom.Sorry i am new to this forum

[seVEMes]

Here is a very useful link from the National Instruments site that helps consider resolution as well:

Knowledge Base Article 2EFEP6K3: Calculating Camera Sensor Resolution and Lens Focal Length

[rpr]

Thanx mate the link was really useful

[muks]

Have you now got an idea for determining the best lens. It depends on a lot of things rpr.Even machine space and asthetic look plays a role in determining the lenses and lightings.

[rpr]

Yup i get a clearer image using 25mm navitar lens than the 6mm one.Though the working distance is going to be high.You are right while saying aesthetics play a role afterall.

am trying to design my first machine vision system.

[AnalogKid2DigitalMan]

rpr (We meet again!)

I find the USAF 1951 Resolution target handy to have on hand along with a few others to determine the quality of an imaging system.

http://www.edmundoptics.com/onlinecatalog/browse.cfm?categoryid=289

-AK2DM