The latest on D7000 skin tones?

Started May 24, 2011 | Discussions thread
rhlpetrus
Forum ProPosts: 23,284Gear list
Like?
metamerism
In reply to Cytokine, May 25, 2011

Cytokine wrote:

rhlpetrus wrote:

If one checks the color depth indexes for a few Nikons, including the ones mentioned in these posts, at DxO Mark RAW tests, we see that there are 3 groups: the early 6MP CCD sensor cameras at 20bits, the 10MP CCD sensor generation and he first two generations of CMOs APS-C sensors (D200, D2x, D300) at 22 bits, then the D7k sensor and D700, both at same level (23.5 bits), then the amazing D3x's sensor (24.7 bits), see list below.

By the way D200 is CCD dual channel sensor not CMOS, Nikon's Patent and the only one ever made.

It's above: "the 10MP CCD sensor generation ... " which includes the D200, D80, D40X, D60, D3000. The dual channel design was used to speed up frame rate, since CCD sensors have a read system that limits the read speed compared to CMOS, but the basic sensor abilities are very similar.

If one takes into account that the D3x's sensor is 2.25 x larger in area as the D7k's, that is exactly reflected in the 1.2 bit more in color depth, so CFA and algorithms used for D7k are at about the same technological level as those of the D3x's.

D70 - 20.4 bits
D300 - 22.1 bits
D2xs - 22.2 bits
D200 - 22.3 bits
D7k - 23.5 bits
D700 - 23.5 bits
D3x - 24.7 bits

Here is how DxO Mark comment on their score:

"The best image quality metric that correlates with color depth is color sensitivity. Color sensitivity indicates to what degree of subtlety color nuances can be distinguished from one another, often meaning a hit or a miss on a pantone palette. Maximum color sensitivity reports, in bits, the number of colors that the sensor is able to distinguish."

So how does that square with the DXO Sensitivity metamerism Ind.,?
Standard ISO 17321. CIE/D50 (Matching Daylight Source)
D300/D200/D70 = 84
D2Xs D700/D5000 = 83
D3000 = 80
D80/D3x = 79
D7000/D5100 = 78
D3/D300s = 77

This has been discussed in some threads in the upper forums and some of the techheads mention that the metamerism index, although relevant, is tricky as an indicator of color separation.

They are two different things: how similar hues colors are separated and how many different levels for each color camera is able to distinguish.

And difference re D700 and D3/D3s in that index shows it may have a very large variability in terms of precision, since it's basically assumed those two cameras use same CFA and algorithms. At least everything else for them is just same, including Color Depth. See what DXO Mark says about it:

"In practice, the SMI for DSLRs ranges between 75 and 85, and is not very discriminating. It is different for low-end cameras (such as camera phones) which typically have a SMI of about 40. For this reason, we give this measurement as an indication but did not integrate it in DxO Mark."

Go back to your own thread, check D300 and D300s numbers: 84 x 70. This can't be taken as a good measure of anything, if it varies so much for what are basically same cameras.

http://forums.dpreview.com/forums/read.asp?forum=1039&message=36903867

So, all this about D70 or D200 or D2x having better colors than D7k or D700 or D3x are not really justified by the measurements.

There is allot of extra technology going on in the D3 and D3x to create accurate colours, the question is rightly being asked has the D7000 inherited this or is this a new Nikon approach. John

It's difficult to say if they are same or not in all aspects (D3x and D7k), but one would guess Nikon uses similar technologies for each generation of cameras. Now, D3 and D3x have very different sensors, one is a Nikon design, the other a Sony. The latter employs a parallel column structure, also used by D7k, which seems to be better for base ISO DR, for example, but not so well adapted to high ISO performance, even though the D7k has reduced that gap (but still D3s is about 2 stops better than D7k, and sensor area is only 2.25 higher, so D3s high ISO tech is different).

-- hide signature --

Renato.
http://www.flickr.com/photos/rhlpedrosa/
OnExposure member
http://www.onexposure.net/

Good shooting and good luck
(after Ed Murrow)

 rhlpetrus's gear list:rhlpetrus's gear list
Nikon D7000 Nikon 1 V1 Nikon AF-S DX Nikkor 12-24mm f/4G ED-IF Nikon AF Nikkor 35mm f/2D Nikon AF-S Nikkor 70-300mm f/4.5-5.6G VR +3 more
Reply   Reply with quote   Complain
Post (hide subjects)Posted by
;-)New
Keyboard shortcuts:
FForum PPrevious NNext WNext unread UUpvote SSubscribe RReply QQuote BBookmark post MMy threads
Color scheme? Blue / Yellow