www.photomacrography.net :: View topic - Shooting at lesser magnification to increase DOF?
www.photomacrography.net Forum Index
An online community dedicated to the practices of photomacrography, close-up and macro photography, and photomicrography.
Photomacrography Front Page Amateurmicrography Front Page
Old Forums/Galleries
 
 FAQFAQ   SearchSearch   MemberlistMemberlist   UsergroupsUsergroups   RegisterRegister 
 ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in 
Shooting at lesser magnification to increase DOF?

 
Post new topic   Reply to topic    www.photomacrography.net Forum Index -> Macro and Micro Technique and Technical Discussions
View previous topic :: View next topic  
Author Message
cactuspic



Joined: 26 Dec 2006
Posts: 432
Location: Dallas, TX

PostPosted: Sun Jul 03, 2016 9:45 am    Post subject: Shooting at lesser magnification to increase DOF? Reply with quote

Recently, I was corresponding with another macro shooter who stated:

"...but the inherent narrow DoF, even at f/16, quite often leaves some of the subject outside of acceptable focus. Quite often, we will photograph a subject at less than 1:1 mag, but deeper DoF. We then crop to the same size as if shot at 1:1, but now with a better DoF."

I know depth of field can be an elusive concept when pressed, but the statement runs counter to my gut instincts. It seems to me that at a consistent fixed viewing distance, the depth of field is also a function of enlargement. It begs for an experimental test that I will be unable conduct until I get back into my studio (in another 2 weeks.) In the interim, my curiosity is burning. Has anyone confronted this question before? Can you improve depth of field over the depth of field attainable at 1:1 by taking the images at a lesser magnification and subsequently cropping the image to a comparable size?
Back to top
View user's profile Send private message Visit poster's website
Pau
Site Admin


Joined: 20 Jan 2010
Posts: 4839
Location: Valencia, Spain

PostPosted: Sun Jul 03, 2016 10:29 am    Post subject: Reply with quote

If what you want is lower resolution and more noise...it will work, in fact it's like shooting with a smaller aperture (and so smaller NA) with the added inconvenience of using only a part of the sensor.

It's like inventing a perpetual movement machine, interesting at first though if you ignore Physics laws but...
_________________
Pau
Back to top
View user's profile Send private message
cactuspic



Joined: 26 Dec 2006
Posts: 432
Location: Dallas, TX

PostPosted: Sun Jul 03, 2016 11:44 am    Post subject: Reply with quote

Thanks, Pau. In applying the no free lunch rule, I was wondering where the payment would come from.
Back to top
View user's profile Send private message Visit poster's website
ChrisR
Site Admin


Joined: 14 Mar 2009
Posts: 8394
Location: Near London, UK

PostPosted: Sun Jul 03, 2016 2:22 pm    Post subject: Reply with quote

You can get an extra benefit from cropping...

If you're photographig, say, a butterfly, whose wings are in a plane which is at an angle to your sensor, you can twist your camera to align them better.
Then you can crop off the side of the image you don't want.

Not as nice as a tilting lens, but hey.
_________________
Chris R
Back to top
View user's profile Send private message
cactuspic



Joined: 26 Dec 2006
Posts: 432
Location: Dallas, TX

PostPosted: Sun Jul 03, 2016 4:59 pm    Post subject: Reply with quote

Thanks Chris. I do play with a homemade tilting macro lens, a reversed 90mm APO Componon, but it is not the quickest or most elegant to adjust when photographing lively critters.
Back to top
View user's profile Send private message Visit poster's website
ChrisR
Site Admin


Joined: 14 Mar 2009
Posts: 8394
Location: Near London, UK

PostPosted: Sun Jul 03, 2016 6:37 pm    Post subject: Reply with quote

No it's not, is it! I've tried a few floppy bellows arrangements. Much easier to tilt the camera about (though it doesn't work as well) but it's hard to not use all those pixels we paid so much for even if we only need a small image.
This ties in with your other shooter's quote about "acceptable focus" and "better dof". It can be better to give up some sharpness in the sharpest parts to get more of the image recognizable - acceptably sharp. ?
_________________
Chris R
Back to top
View user's profile Send private message
cactuspic



Joined: 26 Dec 2006
Posts: 432
Location: Dallas, TX

PostPosted: Sun Jul 03, 2016 8:06 pm    Post subject: Reply with quote

Agreed Chris. It's a decision I have made with the diffraction devil Evil or Very Mad many times...gladly. Smile
Back to top
View user's profile Send private message Visit poster's website
Display posts from previous:   
Post new topic   Reply to topic    www.photomacrography.net Forum Index -> Macro and Micro Technique and Technical Discussions All times are GMT - 7 Hours
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum


Powered by phpBB © 2001, 2005 phpBB Group