APS-C Image Quality (7d vs nex7)

[akiskev]

I took a sample image from Imaging Resource's review of Sony Nex 7 and compared it with the same sample shot from  Canon 7D review (which btw has same iq with 60d,600d and 550d as expected). The difference in IQ is VAST! Please take a look at the two 100% crop comparisons I made (both shots taken with the same Sigma lens).

7d vs Nex 7 1
7d vs Nex 7 2

How can we justify such a big difference? Is it the new Sony sensor? Is it the crappy jpeg output of Canon?
If the test is legitimate, then Sony has by far the best aps-c sensor out there. It delivers unbelievable quality even when reviewing the images at 100% (pixel peepers rejoice!).

PS Remember that this comparison is only about image quality. We all know the differences between a high end dslr and a mirrorless camera.

[Jettatore]

Many variables can affect results  http://en.wikipedia.org/wiki/Scientific_method

Without having access to all the variable details, it would seem impossible to answer.

[koolman]

It is very hard to use these to "comparisons" in any useful way - as each camera has fine tuning that optimizes performance. (picture styles, sharpness and saturation settings, etc.)

I must say however - that my brother in-law visited me for a few days last month. He came with his 7d + canon 24-70. I used My canon t2i + tamron 17-50 NON vc.

My IQ was consistently better then his. I "played" with the 7d extensively, attached my Tamron to it, and tried it as well with a canon 50 1.4.

Bottom line - for a reason I dont understand - the 7d was somewhat "soft" / "mushy" compared to the t2i !!!

It was hard for me to believe. I then read many such postings of 7d owners complaining of a "softness".

It could be that the 7d emphasis is more on speed then IQ ? I also found the 7d's center focus point - to get less tack sharp results then the "cheapi" t2i.

[dr croubie]

Those differences can be down to:
Lens, ISO, aperture, raw-or-jpg, picture style and sharpness setting, noise reduction, processing software used.
Out of them, i'd presume raw/jpg and sharpness setting would be making the biggest difference of them.

To control variables, you can mount an EF-lens on a NEX via an adapter, use DXO or something to process both shots with the same noise-reductions etc.
But some variable you can't control, like just because the camera says iso100 doesn't mean it's actually iso100, and picture-styles are going to be brand- and probably even sensor-dependent.

I'll be waiting until DXOMark does their nex7-review before passing judgement.

[briansquibb]

Looks like the 7D photos still have the default sharpness setting of 3. If so then out of the box this is probably right - but then the 7D is set for providing unsharpened images to libraries and editors whereas the Nex7 is set up to produce photos for the coffee table

Brian

[dr croubie]

Bottom line - for a reason I dont understand - the 7d was somewhat "soft" / "mushy" compared to the t2i !!!

It was hard for me to believe. I then read many such postings of 7d owners complaining of a "softness".

Bryan also talks about the 7D being a bit 'soft' compared to other cameras, just set the sharpness to '3' and don't worry.

I also found the 7d's center focus point - to get less tack sharp results then the "cheapi" t2i.

With the same lenses on different cameras? could be an AF issue, but only the 7D can AF Microadjust...

[briansquibb]

It could be that the 7d emphasis is more on speed then IQ ? I also found the 7d's center focus point - to get less tack sharp results then the "cheapi" t2i.

More likely the setup of the 7D which is the problem. I have 2 7D's are they are both spot on sharp.

I have heard from 7D owners about this softness and they have sent them back to Canon etc and still been soft. Then you hear they shoot in jpeg using the default settings and not sharpened them.  Out of the box the 7D will always look soft. So a P&S convert will always be complaining about soft images.

[candyman]

It could be that the 7d emphasis is more on speed then IQ ? I also found the 7d's center focus point - to get less tack sharp results then the "cheapi" t2i.

More likely the setup of the 7D which is the problem. I have 2 7D's are they are both spot on sharp.

I have heard from 7D owners about this softness and they have sent them back to Canon etc and still been soft. Then you hear they shoot in jpeg using the default settings and not sharpened them.  Out of the box the 7D will always look soft. So a P&S convert will always be complaining about soft images.

So you are shooting with the 7D and what is your 7D built-in sharpnesssetting? Or do you sharpen your RAW photo afterwards?

[PeterJ]

I must say however - that my brother in-law visited me for a few days last month. He came with his 7d + canon 24-70. I used My canon t2i + tamron 17-50 NON vc.

My IQ was consistently better then his. I "played" with the 7d extensively, attached my Tamron to it, and tried it as well with a canon 50 1.4.

Bottom line - for a reason I dont understand - the 7d was somewhat "soft" / "mushy" compared to the t2i !!!

I moved from a 450D, which in latter parts I was shooting in RAW to a 7D (with which I've always used RAW) and had similar issues at first. My "problem" was solved once I read the manual and came to grips with all the autofocus options and found what suited me. I'm an amateur and not having a go at you in any way, just for me at least it is a camera that can take a bit to get the best from but results can be awesome as you get used to it . I now despise and never use any of the AF modes that automatically pick points.

[dilbert]

Bottom line - for a reason I dont understand - the 7d was somewhat "soft" / "mushy" compared to the t2i !!!

It was hard for me to believe. I then read many such postings of 7d owners complaining of a "softness".

Sounds like lens calibration is required:

http://www.canonrumors.com/tech-articles/this-lens-is-soft-and-other-myths/

[NormanBates]

@Koolman:

my bet is that you were using AF, and didn't calibrate your focus with the 7D and either of the lenses you used
http://www.lensrentals.com/blog/2008/12/this-lens-is-soft-and-other-myths
http://www.lensrentals.com/blog/2010/03/this-lens-is-soft-and-other-facts
http://www.similaar.com/foto/tuten/510.html
i.e. what dilbert said: we were posting at the same time, but my post was longer

about the 7D vs NEX7 issue:
* it could also be an AF issue: the NEX7 uses contrast-detect AF so it is slow but always on target; the 7D uses phase detect AF, which is fast but will generate systematic errors unless calibrated correctly:
http://www.similaar.com/foto/tuten/510.html
* it could be that they're using the same model of lens for both cameras, but one lens is fine and the other is soft
http://www.lensrentals.com/blog/2011/10/notes-on-lens-and-camera-variation
* it could be a sharpness-in-post issue: on those samples, I see lots of double-lining on the NEX7 samples, in the doors, windows, etc
* I don't think it is a sensor thing: the DXOmark comparison of A77 vs 7D is kind of a tie:
http://www.dxomark.com/index.php/Cameras/Compare-Camera-Sensors/Compare-cameras-side-by-side/(appareil1)/734%7C0/(brand)/Sony/(appareil2)/619%7C0/(brand2)/Canon
take the SLT mirror of the A77 away, and the NEX7 may be beating the 7D, but not by much

[EYEONE]

Looks more like a lens difference than a sensor difference.

I have sharpness on my 7D set to 5 or 6, shoot RAW and use L glass. It's tack sharp.

[torger]

Probably a lens difference, and jpeg settings etc. There is no extreme AA filter on the 7D sensor so if the lens is sharp and your tripod does not vibrate, your focus is right etc you get sharp pixels.

However what we do know is that the 7D sensor has at ISO100 pattern noise issues in dark shadows and considerably less dynamic range than compared to the best current APS-C sensors. At higher ISOs the sensor fares quite well though.

[KeithR]

How can we justify such a big difference?

Some Real World 7D output:

http://www.capture-the-moment.co.uk/tp/tfu29/upload/reworks/turnstone_bridlington_1b.jpg
http://www.capture-the-moment.co.uk/tp/tfu29/upload/reworks/turnstone_bridlington_2.jpg

Taken with the 7D/100-400mm, handheld at 400mm. Converted in Capture One 6, PP in CS4.

Nothing much wrong with these...

Or this:

http://www.capture-the-moment.co.uk/tp/tfu29/upload/dog_big.jpg

[KeithR]

However what we do know is that the 7D sensor has at ISO100 pattern noise issues in dark shadows and considerably less dynamic range than compared to the best current APS-C sensors.

Not strictly true - what we know is that the 7D needs the user to apply some intelligence and discernment in his choice of conversion software. I've cranked low ISO 7D shots up by 4 or more stops without any problem in the shadows.

http://www.capture-the-moment.co.uk/tp/tfu29/upload/shadows.jpg
http://www.capture-the-moment.co.uk/tp/tfu29/upload/shadows_recovered.jpg

http://www.capture-the-moment.co.uk/tp/tfu29/upload/IMG_2195_minus_3_ev.jpg
http://www.capture-the-moment.co.uk/tp/tfu29/upload/IMG_2195-plus_4_ev.jpg