NEX-7 problem with CZ85

[douglasf13]

Thanks Douglas:

The 16Mp sensor on the new Ricoh GXR zoom will be interesting as Ricoh have said there is no AA filter on it - so this should be the same as a 5N "unplugged"

Keith

Potentially. Granted, I can't say for sure that Ricoh doesn't spend the money on designing new micro lenses, I just doubt it. They also likely use their own color filter, so there would be differences there.

 

[scho]

To tell you the truth, we don't actually know whether the "special" micro lenses are anything more than marketing speak, like with the M9. Removing the AA filter could be the only real difference between how the GXR and the 5N behave with symmetrical wides. Who knows?

Removing the AA filter is an entire subject on its own, with both positives and negatives. The major camera companies generally tend to use AA filters, because they feel the positives outweigh the negatives, but, with a camera like NEX that has such a short registration distance, I agree that they should've gone ahead and yanked it, as it would not only improve rangefinder lens performance at the edges, but also e-mount lens performance (slr lenses, too, to a lessor extent.) Granted, I'd guess video performance is another reason Sony is shackled to using AA filters. Ricoh, Fuji and Leica don't have to cater to the video crowd, much, but Sony is forced to make video compromises.

Speaking of video. Is there any way to disable that pesky red video button that always seems to get accidentally turned on at the wrong moment?

 

[douglasf13]

Unfortunately, no. Disabling the video button has been a common firmware update request.

 

[uhoh7]

For M and LTM even the current M module for the GXR seems way ahead.

Even the focusing is apparently more accurate--but uglier.

I just hope my 5n lasts untill we have FF EVIL with decent sensor.

 

[woodmancy]

This one works fine with no corner issues. Maxxum lenses fit the Nex well with the LA-EA1 adapter - nice handling package (even lighter with the Nex 5n)

Keith

 

[Vivek]

I happened stumble upon a 28mm T/S that I used to use on Nikon DSLRs and tried it on the NEX-7. Tilted to more than 15 deg. No worries.

 

[douglasf13]

Photozone published a couple of lens reports on the NEX-7:

Sony E 30mm f/3.5 macro (SEL-30M35) - Review / Test Report

Sony E 50mm f/1.8 OSS (SEL-50F18) - Review / Lens Test

 

[thrice]

I happened stumble upon a 28mm T/S that I used to use on Nikon DSLRs and tried it on the NEX-7. Tilted to more than 15 deg. No worries.

Surely shift would be much more problematic than tilt, you don't change the incident angle very much with front tilt... *view camera 101*

 

[Vivek]

Excellent point , Daniel! However, the particular 28mm T/S lens I tried has to shift during the tilting process and the degree of movements affecting the incident angle is determined by the exit pupil.

No worries at all with the NEX-7 when I compare how that lens performed on a 10mp Nikon DSLR.

 

[waardij]

Lloyd Chambers suggest that a thick cover glass is the problem with the NEX-7. This would concur with what Zeis is saying about the use of certain lenses on digital (cover glass/filter interferes with edge performance of certain lenses).

http://diglloyd.com/...ro1-sensor.html

 

[Vivek]

There is no useful link.

Do you know how much glass is involved and how much is too much?!

FYI, Nikon DSLRs have far too much glass between the sensor and the lens than the Sony NEXs.

Typically, ~3.5mm (total) for Nikon and ~2.2mm (total) for Sony. m4/3rds have ~5mm (!) of glass.

 

[waardij]

If you look at page 12 of this paper, it is explicitly mentioned that Leica uses thin glass to make the M digital work with rangefinder lenses (in this case the biogon design).

http://blogs.zeiss.com/photo/en/wp-content/uploads/2011/12/en_CLB41_Nasse_LensNames_Distagon.pdf

 

[Vivek]

Yes, I am aware of that.

That does not mean

1. Zeiss performs better than Leica lenses on M digital bodies.

2. Llyod Chambers isn't the author and the earlier link posted gets nowhere.

3. Nikon and others have thicker glass on the sensor than the NEX- a fact.

So, this hypothesis that NEX has more glass on the sensor than others and presumably manufactures a non existent problem is incorrect.

 

[waardij]

I do not think it is a not existing problem. I also think it is not such a big deal as suggested on some places. But I do see, for myself, that the CZ85mm f1.4 performs better, edges and corners, on the 5n as it does on the 7.
I also think the 7 is a brilliant little camera, but it is a pity that Sony has not used the same ‘solution’ as they have used on the 5n.

 

[Vivek]

For the money, it is a lot. Can't say the same thing about the lenses though.

The Fuji X Pro 1 is a bit more expensive but looks (not the appearance) a lot better. The lenses there have no such issues, it seems.

 

[monza]

Have there been any further updates to this potential issue?

 

[sergio lovisolo]

I think that a problem exists.
I have been testing a few leica r lenses on the nex 7, and particularly on the
elmarit 19 II and elmarit 35 I noticed soft borders and corners.
Those lenses are retrofocus design, and should be perfectly compatible with
the nex so at beginning I attributed the fault to the lenses.
I was planning to use the lenses on a (still unavailable) d800, so I borrowed
a D700 to see if the problem persisted with this camera also.
To my surprise, and in particular the elmarit 19, the leicas were quite sharp
on the whole field at infinity.
The following test seems to indicate strong field curvature at the lateral borders
of the nex7 sensor.

Full image on d700, elmarit 19- f5,6-infinity focus

DSC_6231 by sergio lovisolo, on Flickr

D700 crop

DSC_6231a by sergio lovisolo, on Flickr

nex 7 full image elmarit 19-f5,6-infinity


_DSC0852 by sergio lovisolo,
on Flickr

nex 7 crop

_DSC0852a by sergio lovisolo, on Flickr

It seems to me that while the crop from the d700 is out of focus as correct,for
a shot taken at infinity, the crop from the same image area with the nex7 is in full focus while in other shots with all image at infinity that same area is soft.

Note that apparently the same image taken with the kit lens at 19 on the same
conditions is out of focus in correspondence of the crop.

Suspects?

Sergio
a

 

[douglasf13]

Wow, Sergio, that's a pretty wild test result. Something certainly seems strange there.

FWIW, according to some on other forums, this phenomena may not be limited to the NEX-7. From what I understand, the D3x shows a much flatter field at the sensor edges than the A900 when using the same lens. It apparently has to do with sensor toppings.