Open Photography Forums  
HOME FORUMS NEWS FAQ SEARCH

Go Back   Open Photography Forums > Photography Discussions > Medical-Forensic-Scientific-Legal-etc

Reply
 
Thread Tools Display Modes
  #1  
Old November 24th, 2013, 04:03 AM
fahim mohammed fahim mohammed is offline
Senior Member
 
Join Date: May 2008
Posts: 7,103
Default Which lens for Macro?


Better than 1:1 :)
Reply With Quote
  #2  
Old November 24th, 2013, 04:32 AM
Tom dinning Tom dinning is offline
Banned
 
Join Date: Mar 2012
Location: Darwin NT Australia
Posts: 2,088
Default

Is that the new toy?
Reply With Quote
  #3  
Old November 24th, 2013, 11:44 AM
fahim mohammed fahim mohammed is offline
Senior Member
 
Join Date: May 2008
Posts: 7,103
Default

Quote:
Originally Posted by Tom dinning View Post
Is that the new toy?
Neither new nor mine, Tom.

Someone wanted to show me what they were seeing in a certain tissue sample of mine. Talk about macro!!

p.s. i did not understand a thing.
Reply With Quote
  #4  
Old December 8th, 2016, 10:48 PM
Dr Klaus Schmitt Dr Klaus Schmitt is offline
Senior Member
 
Join Date: Jul 2010
Location: Weinheim, Germany
Posts: 1,002
Default

http://macrolenses.de

Go choose....
__________________
Klaus
https://www.flickr.com/photos/kds315/ my normal photographic work
http://photographyoftheinvisibleworld.blogspot.com/ my ultraviolet (UV) work
Reply With Quote
  #5  
Old December 9th, 2016, 08:10 AM
Doug Kerr Doug Kerr is offline
Senior Member
 
Join Date: May 2006
Location: Alamogordo, New Mexico, USA
Posts: 8,197
Default

I will take this opportunity to remind us that the infamous "1:1" image magnification, often used as the criterion of "real macro performance" for a lens, is not very definitive with regard to our actual photographic needs.

Almost always, what we are really interested in is what sized object (or object field) will fill our frame. At the "1:1" benchmark, that is a field whose size equals the fame size. For a camera with a four-thirds sensor, that would be an object less than 13.5 mm in diameter (about 2/3 the diameter of an American dime coin).

For an 8" 10" format camera, that object might be a ladies' shoe.

Best regards,

Doug
Reply With Quote
  #6  
Old December 10th, 2016, 12:58 PM
fahim mohammed fahim mohammed is offline
Senior Member
 
Join Date: May 2008
Posts: 7,103
Default

Sure.

Best regards.
Reply With Quote
  #7  
Old October 21st, 2017, 05:14 PM
Dr Klaus Schmitt Dr Klaus Schmitt is offline
Senior Member
 
Join Date: Jul 2010
Location: Weinheim, Germany
Posts: 1,002
Default

Quote:
Originally Posted by Doug Kerr View Post
I will take this opportunity to remind us that the infamous "1:1" image magnification, often used as the criterion of "real macro performance" for a lens, is not very definitive with regard to our actual photographic needs.

Almost always, what we are really interested in is what sized object (or object field) will fill our frame. At the "1:1" benchmark, that is a field whose size equals the fame size. For a camera with a four-thirds sensor, that would be an object less than 13.5 mm in diameter (about 2/3 the diameter of an American dime coin).

For an 8" 10" format camera, that object might be a ladies' shoe.

Best regards,

Doug
Ehemm Doug, sorry, but at 1:1 the object size is identical to the size on the sensor, i.e. a 1mm object will be exactly 1mm on the sensor. It has nothing to do with sensor size nor field size, it is a parameter of the lens only.
__________________
Klaus
https://www.flickr.com/photos/kds315/ my normal photographic work
http://photographyoftheinvisibleworld.blogspot.com/ my ultraviolet (UV) work
Reply With Quote
  #8  
Old October 21st, 2017, 06:25 PM
Asher Kelman Asher Kelman is online now
OPF Owner/Editor-in-Chief
 
Join Date: Apr 2006
Posts: 32,779
Default

Klaus, is he starting from the standpoint "where we have no units of measurement", just some camera. In that world one could say that a 1:1 image that fills sheet of film is that size too.

Asher
__________________
Follow us on Twitter at @opfweb

Our purpose is getting to an impressive photograph. So we encourage browsing and then feedback. Consider a link to your galleries annotated, C&C welcomed. Images posted within OPF are assumed to be for Comment & Critique, unless otherwise designated.
Reply With Quote
  #9  
Old October 21st, 2017, 07:22 PM
Doug Kerr Doug Kerr is offline
Senior Member
 
Join Date: May 2006
Location: Alamogordo, New Mexico, USA
Posts: 8,197
Default

Hi, Klaus,
Quote:
Originally Posted by Dr Klaus Schmitt View Post
Ehemm Doug, sorry, but at 1:1 the object size is identical to the size on the sensor, i.e. a 1mm object will be exactly 1mm on the sensor.. . .
Quite so.

Quote:
It has nothing to do with sensor size nor field size . . .
Quite so.

Quote:
. . .it is a parameter of the lens only.
Quite so.

Now, all that having been said, if we are operating at a magnification of 1:1, and our frame size is 36 mm 24 mm, then the size of the object field (at the object distance for which the magnification is 1:1, at which distance we presumably are focused) will be 36 mm 24 mm, for the very reasons you cite. If our frame size is 11 in. 14 in., then the size of the object field is 11 in. 14 in.

And my point is that if macrophotography is to be thought of as the photography of small (but not microscopic) objects, I don't consider an object that occupies most of an 11 in. 14 in. region "small".

Best regards,

Doug
Reply With Quote
  #10  
Old December 3rd, 2017, 05:39 PM
Dr Klaus Schmitt Dr Klaus Schmitt is offline
Senior Member
 
Join Date: Jul 2010
Location: Weinheim, Germany
Posts: 1,002
Default

Absolutely Doug, I just wanted to be clear. Surely, there were lenses built for shipbuilding drawings which copied 1:1, not what I woudl call "m,acro" rather than "repro"
__________________
Klaus
https://www.flickr.com/photos/kds315/ my normal photographic work
http://photographyoftheinvisibleworld.blogspot.com/ my ultraviolet (UV) work
Reply With Quote
  #11  
Old December 4th, 2017, 08:07 AM
Doug Kerr Doug Kerr is offline
Senior Member
 
Join Date: May 2006
Location: Alamogordo, New Mexico, USA
Posts: 8,197
Default

Hi, Klaus,

Quote:
Originally Posted by Dr Klaus Schmitt View Post
Absolutely Doug, I just wanted to be clear. Surely, there were lenses built for shipbuilding drawings which copied 1:1, not what I woudl call "m,acro" rather than "repro"
Of course.

Best regards,

Doug
Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are Off
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Canon EOS Autofocus - BFCV and micro-adjust (MA) Doug Kerr Imaging Technology: Theory, Alternatives, Practice and Advances. 11 November 14th, 2011 03:44 PM
Eyeglass lenses and "vertex power" Doug Kerr Imaging Technology: Theory, Alternatives, Practice and Advances. 0 November 10th, 2010 07:47 AM
Lens MTF and resolution Doug Kerr Imaging Technology: Theory, Alternatives, Practice and Advances. 3 October 16th, 2010 07:36 AM
Sigma 18-250mm f/3.5-6.3 DC OS HSM zoom lens - Part 1 Doug Kerr Lenses: DSLR and Rangefinder, MF adaptions to 35mm such Zoerk 10 December 8th, 2009 09:46 PM
Understanding and selecting lenses Rhys Sage Layback Cafe 13 September 13th, 2008 09:47 AM


All times are GMT -7. The time now is 12:23 PM.


Posting images or text grants license to OPF, yet of such remain with its creator. Still, all assembled discussion 2006-2017 Asher Kelman (all rights reserved) Posts with new theme or unusual image might be moved/copied to a new thread!