DPReview.com is closing April 10th - Find out more

Long Telephoto lenses and increasing depth of field?

Started Jun 20, 2019 | Discussions thread
drj3 Forum Pro • Posts: 12,632
Re: You get same DOF....
1

C Sean wrote:

You can only get so far all the magnifications same, but never get the same perspective or background blur, but the DOF will be same.

I imagine you can zoom out a bit to increase the DOF and crop in later if you have spare megapixels but in general use of long telephoto lenses is because you can get close to the subject by foot.

It will not help to zoom out and then crop.  The DOF will decrease as you crop (equivalent to increasing the image size without changing viewing distance or decreasing the viewing distance for an image of a given size).

See the attached example of the full image with a DOF of the center nail head of 2.1 inches and then the crop where the DOF is close to the width of the nail head (about .25 inches).  The images were done for focus accuracy tests on my lens.

-- hide signature --

drj3

 drj3's gear list:drj3's gear list
Olympus E-510 Olympus E-5 Olympus E-M1 Olympus OM-D E-M10 Olympus E-M1 II +13 more
Keyboard shortcuts:
FForum PPrevious NNext WNext unread UUpvote SSubscribe RReply QQuote BBookmark MMy threads
Color scheme? Blue / Yellow