Return of Interesting article on DxO about 5D III and D800...

Started Apr 10, 2013 | Discussions thread
Mikael Risedal
Veteran MemberPosts: 3,263
Like?
Re: Return of Interesting article on DxO about 5D III and D800...
In reply to qianp2k, Apr 11, 2013

qianp2k wrote:

Steen Bay wrote:

qianp2k wrote:

Steen Bay wrote:

qianp2k wrote:

Steen Bay wrote:

aftab wrote:

Now, let us look at scenario B and scenario C again. In both cases A looks sharper than B. What does that mean? More resolution = more sharpness. That is resolution = sharpness in this two scenarios. And almost all scenarios are like this. So, we can actually use the terms resolution and sharpness interchangeably.

But if comparing for example the 12.7mp 5D vs. the 18mp 7D, then things get a bit more complicated, because it seems that 5D (most often, with most lenses) has the best sharpness (MTF-50?),

true.

while the 7D has the highest resolution (MTF-10 or MTF-5?).

Not necessarily. Actually with most  EF lenses 5D outresolves 7D if you frame them in the same AOV (as tested by DXOMark in either old MTF or new P-MPix unit that are two different expressing units but with the same result). Only very few lenses such as with 300L/2.8 IS II 7D/60D outresolves 5D.

-- hide signature --

But what if we could compare the MTF-10 er MTF-5 values (which we unfortunately can't anymore)? Then I think that the 7D would win, because it has quite a bit more MPs.

In theory maybe.  But it's a matter of our eyes can resolve or not that's all DXOMark test about, a paper resolution vs real resolution after deducting noise/grain, pixel magnification...  It’s a matter of perceptual sharpness (resolution) human eyes can perceive.

http://www.cambridgeincolour.com/tutorials/lens-quality-mtf-resolution.htm

-- hide signature --

Yes, it's a matter of what the human eye can perceive, so how about comparing the resolution test chart shots in DPR's 5D and 7D reviews? (available for download). Haven't checked, but as far as I remember, then the 7D wins.

I don't think so with most EF lenses, 5D gains more with inferior lenses if you test by framing them in the same AOV.  I did such test other day (and will do again) that show 5D has resolution advantage except with the best lens 24-70L II in very close distance (macro mode) against a dollar bill but that is a very small center area (and 5D wins in edges/corners).  In real world outdoor test, 5D wins clearly.  I think DXOMark uses average frame resolution to calculate its DXOMark number.

http://www.dpreview.com/forums/thread/3447852

-- hide signature --

off course, a APS camera as 7d needs 1,5 - 1,6 better lenses if you compare to 18Mp at 24x36 surface , it means the 7d demands  better contrast and resolution

-- hide signature --

Member of Swedish Photographers Association since 1984
Canon, Hasselblad, Leica,Nikon, Linhoff, Sinar
Member of International anti-banding and read out noise Association

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