Latest or all posts or last 15, 30, 90 or 180 days.
Upgrade the memory of your 2018 Mac mini up to 64GB

No 85mm/f1.2L double image in out-of-focus background when shooting infrared

In my August 2 entry , I confirmed a double-image with the Canon EF 85mm/f1.2L II USM beginning at about 60% away from the optical center, worsening as the image becomes increasingly out of focus.

I have since verified that this problem does not occur when shooting in infrared, thus establishing that the problem is a form of chromatic aberration, and an excellent example of how real and theoretical depth of field are often at odds when chromatic aberrations are present. Though the color (visible light) image was shot with the 1Ds Mark II, and the infrared image was shot with the 5D, I think the results can be trusted (besides, I’m not going to convert a 1Ds Mark II to infrared!).

More than likely what’s going on is that by shooting in infrared, a narrower spectral band is used, and thus the color fringing seen in visible light (due to the broad spectral range) simply doesn’t occur. A common misconception is that infrared images are not sharp as sharp as visible light images; this is simply untrue and will be explored in a future article. Both images below are well out of focus at f1.2.

EF 85mm/1.2L II USM on EOS 1Ds Mark II
f1.2 @ 1/160 sec
65mm behind plane of focus
80% of the way from center to right edge
EF 85mm/1.2L II USM on Canon 5D
f1.2@ 1/100 sec
80mm behind plane of focus
85% of the way from center to right edge
128GB Memory in iMac 5K

Up to 128GB for 2019 iMac 5K!
Up to 64GB for 2015/2017 iMac 5K

Save nearly 50% over Apple pricing
Organic Lab Tested Full Spectrum CBD

20% off every day with coupon code diglloyd20 at NuLeafNaturals.com

100% organic non-GMO, no additives or preservatives, lab tested for purity and quality.

Save the tax, we pay you back, instantly!
B&H Deal ZoneDeals by Brand/Category/Savings
Deals expire in 7 hours unless noted. Certain deals may last longer.
$2797 SAVE $600 = 17.0% $246 FREE ITEMS Nikon Z 7 Mirrorless in Cameras: Mirrorless
$2798 SAVE $400 = 12.0% Sony a7R III Mirrorless in Cameras: Mirrorless
$3498 SAVE $1000 = 22.0% Sony a9 Mirrorless in Cameras: Mirrorless
$898 SAVE $100 = 10.0% $161 FREE ITEMS Sony DSC-RX100 VA in Cameras: Point and Shoot
$1879 SAVE $1071 = 36.0% ZEISS 15mm f/2.8 Distagon T* ZE in Lenses: DSLR

diglloyd Inc. | FTC Disclosure | PRIVACY POLICY | Trademarks | Terms of Use
Contact | About Lloyd Chambers | Consulting | Photo Tours
RSS Feeds | Twitter
Copyright © 2019 diglloyd Inc, all rights reserved.