Minimum focusing distance/Minimum working distance

[Corey Fehr]

What is the difference between minimum focusing distance and minimum working distance?

I tried doing some research online, and couldn't find a decent comparison. (I mainly just found specs on lenses.)

What differentiates these two terms?

Thanks in advance!

 

[tedr1]

Possibly one is measured from the film plane (focusing distance) and the other is measured from the front of the lens (working distance). There may be other explanations.

 

[MattKing]

The minimum working distance usually refers to the distance between the front of the lens to the subject.
Minimum focus distance seems to vary a bit - one end is definitely the subject, whereas the other end might be a lens nodal point, the front of the lens or the film plane.
By the way, some people who access APUG on smaller screens may see incomplete versions of thread titles, so it is always a good idea to repeat the subject of your query in the post itself.

 

[Corey Fehr]

Thanks!

I'll go edit this right now-thanks for letting me know Matt.

 

[jimjm]

I'd consider minimum working distance to be from the front of the lens to your subject, and focusing distance is from the film plane to the subject.

With a 55mm macro lens focused at 10", the front of the lens itself is actually about 4" from the subject. The difference between these 2 can be significant when you're using a macro lens that's around 50 or 60mm, because you may have to get so close to your subject that you block the light and/or spook it (if it's alive). This is one reason that longer 100 to 200mm macro lenses are often more useful because you can keep a more comfortable distance.

 

[Corey Fehr]

I'd consider minimum working distance to be from the front of the lens to your subject, and focusing distance is from the film plane to the subject.

With a 55mm macro lens focused at 10", the front of the lens itself is actually about 4" from the subject. The difference between these 2 can be significant when you're using a macro lens that's around 50 or 60mm, because you may have to get so close to your subject that you block the light and/or spook it (if it's alive). This is one reason that longer 100 to 200mm macro lenses are often more useful because you can keep a more comfortable distance.

Great-thanks!