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

To stack or not to stack

Started Sep 26, 2019 | Polls thread
gardenersassistant Veteran Member • Posts: 9,656
Re: Larger DOF with larger sensors (not a typo)

John K wrote:

gardenersassistant wrote:

John K wrote:

Not even remotely possible if the aperture stayed the same...

The aperture was different, as clearly stated!

...and that's why the depth of field changed.

Quite so.

Not the sensor size, pixel size, circle of confusion, or any other factor...

Not sure who that comment is directed at, as I have not mentioned circle of confusion or pixel size, and have not claimed that the depth of field changed because of different sensor sizes.

Again: Depth of field is nothing more than a function of magnification and aperture. Minor factors like the circle of confusion

which I have not mentioned, not sure why you are

have very little impact in perceived depth, so if you want more depth at a given Fstop you have to lower the magnification. Small sensors work well for depth of field because you can fill the frame with the subject at lower magnifications.

Small sensors do not work especially well for depth of field because you typically can't use as large f-numbers with small sensor cameras as with cameras with larger sensors, so the end result is that you typically can't get more depth of field with a small sensor. That was illustrated in my previous examples, which showed (largest available f-number) f/8 on 1/2.3" giving the same depth of field as (largest available f-number) f/29-f/32 on APS-C.

Also, small sensor cameras are typically fixed lens cameras which mean you can't use extension tubes, bellows or teleconverters between the lens and the camera. Larger sensor cameras are typically interchangeable lens cameras which can use such devices, which increase the effective f-number, enabling the larger sensor (ILC) cameras to produce greater depth of field than small sensor (fixed lens) cameras, as was illustrated with my latest example.

[Edit: posted illustration replaced below with a corrected version.]

It's really that simple...

My Blog: http://www.extrememacro.com
My gallery: http://www.johnkimbler.com
Macro Tutorials: http://dalantech.deviantart.com/gallery/4122501/Tutorials
Always minimal post processing and no cropping -unless you count the viewfinder...

Post (hide subjects) Posted by
Keyboard shortcuts:
FForum PPrevious NNext WNext unread UUpvote SSubscribe RReply QQuote BBookmark MMy threads
Color scheme? Blue / Yellow