IQ of 7d w 15-85mm Vs 6d w 24-105mm?

Started Mar 8, 2013 | Questions thread
Shop cameras & lenses ▾
Forum ProPosts: 10,350Gear list
Re: presentation.
In reply to Mako2011, Mar 11, 2013

Mako2011 wrote:

usedtobedontrustme wrote:

Mako2011 wrote:

qianp2k wrote:

usedtobedontrustme wrote:

qianp2k wrote:

24-105L on 6D will have much better IQ - sharper, resolve more details, better color tonality, better DR, better SNR (which means less noises/grains in entire ISO range) and of course much better high ISO.

DXOMark 24-105 on 5D2 vs 15-85 on 7D

DXOMark 6D vs 7D sensor test

DXO says the 6d & lens combo has 50% better sharpness. That is huge and I hope that is accurate. 20% better sharpness would be worth it to me.

The reason FF set is sharper is because it has 1.6x less pixel magnfication.

That would indicated a misunderstanding of the things that affect sharpness. Perhaps related to the cloak surrounding M-pix. First, it is important to compare systems at the same DOF when discussing sharpness. You may have not considered that. To compare sharpness you need to start from Equivalent photos. DXO is not doing that. While the overall sharpness is often the same or better with FF, the issue of evenness of frame needs to be considered, and taken on a lens-by-lens basis as well as comparing like photos. Your examples do not do that and DXO makes many of the same mistakes in presentation. Their strike zone is very large...nice for tee ball but not as useful for a fast pitch game game.

Are you saying that DXO doesn't measure sharpness across the whole frame? Does DXO assume that if a lens is wide open, small DOF is necessarily desired?

Not sure. I'm saying they don't really explain well the actual numbers that go into "perceptual megapixels" and "average visual acuity", so the score is less definable than it once was. That leads to the inconsistencies noted. There "sharpness" measure is no longer consistent or definable. Generally in the ball park though and useful for a rough comparison and more useful when combined with reviews from other sites.

DXOMark changed MTF resolution data to P-MPix is for easier understanding as it explained but it doesn't change comparison result. Whatever it showed before with MTF resolution is still the same in P-MPix. I just happened to save a few snapshot from old DXOMark when it used MFT data.

DXOMark explained well in its article  (thru link you can find original DXOmnark link)

It didn't give its formula how to convert MTF to P-MPix of course due to business secrete but it doesn't explain that doesn't change end comparison result but in an easier understood expressing unit.

DXOMark old data (MTF resolution) 24-105L on 5Dc vs on 7D or with comparable EF-S 15-85

-- hide signature --

My opinions are my own and not those of DPR or its administration. They carry no 'special' value (except to me and Lacie of course)

-- hide signature --
 qianp2k's gear list:qianp2k's gear list
Sony RX100 Canon EOS-1D Mark III Canon EOS 5D Mark II Canon EOS 5D Mark III Sony Alpha 7R +20 more
Reply   Reply with quote   Complain
Post (hide subjects)Posted by
Keyboard shortcuts:
FForum PPrevious NNext WNext unread UUpvote SSubscribe RReply QQuote BBookmark post MMy threads
Color scheme? Blue / Yellow