NEX-5n with 12mm Heliar

Matthieu said:
I believe the colour shift is still present, but it's hard to tell from these photos, since they have so much going on. We'd need something of uniform colour, like a white wall or the sky.
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I agree that it's hard to tell.

Ricoh has done a good job with their GXR M-Module with the offset micro lenses optimized for M-Lenses, which means that they are optimized for lenses whose exit pupils are close to the sensor. One would have expected that Sony would optimize the offset micro lenses on the NEX cameras for Sony lenses, which do not have this design of being close to the sensor. I would think Sony would have had to design the new NEX camera for M-type lenses for the wide-angle M-lenses to work well in the corners on the NEX-5n and the NEX-7. We'll see.

—Mitch/Bangkok
Paris au rythme de Basquiat
 
Color shifting & corner sharpness

Color shifting & corner sharpness

I've been using the NEX-5N with Contax G RF lenses (and some M mounts also) and see none of the corner/edge abberations I experienced with m43 bodies and the M8 using same lenses. I don't know what Sony did with the new sensor microlenses, but they seem to have done a good job. I also have the GXR and will do some comparisons when the M module is available.
Here are links to two threads on dpr where the same issue came up and I posted images in reply:

http://forums.dpreview.com/forums/read.asp?forum=1042&message=39311332

http://forums.dpreview.com/forums/read.asp?forum=1042&message=39303042
 
Interesting and looks promising for the NEX-7. One of your pictures is with a 35mm, at which focal length there would not be much of problem; the other one is with a 28mm length, with which the problem would expected to begin. Do you have a 21mm or wider lens to try?

—Mitch/Bangkok
Paris au rythme de Basquiat
 
malland said:
Interesting and looks promising for the NEX-7. One of your pictures is with a 35mm, at which focal length there would not be much of problem; the other one is with a 28mm length, with which the problem would expected to begin. Do you have a 21mm or wider lens to try?

—Mitch/Bangkok
Paris au rythme de Basquiat
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Mitch,

I don't use ultra wides very often, but here is one with the CV 15mm SW Color Heliar and another with the CV 25mm f/4 Skopar p. I also have the Skopar 21 and will give that a try soon.

http://www.pbase.com/scho/image/137739342

http://www.pbase.com/scho/image/137735775

Here is a quick indoor shot with the 21mm Skopar at f/4 ISO 3200 on the NEX-5N

original.jpg
 
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Thanks, eco. All this is interesting and on the face of it looks good, but I still feel that one needs specific test shots (the way Sean Reid does them) to resolve two possible issues: first, that the corners on wide-angle rangefinder lenses — I'm interested in Leica M-lenses — are not subject to softening and colour shift, and, second, that the sensor prerves the quality or characteristics of the original lenses by not having an AA filter, the way that the Leica M8 and M9, and, now, the Ricoh GXR M-A12 M-Module do.

On the M-A12 there is the following new article by Sean Reid that highlights the issues:

http://www.luminous-landscape.com/essays/ricoh_lens_mount_a12.shtml

BTW, I tried out the M-A12 briefly at the Ricoh Camera importer in Bangkok and found that does indeed maintain the characteristics of the DR Summiron 50mm lens, which I find very promising.

—Mitch/Bangkok
Paris au rythme de Basquiat
 
I will try my Canon FD 7.5mm on a 4/3 camera as a comparison.It should display all faults that the lens in this thread is claimed not to display.
 
raid said:
I will try my Canon FD 7.5mm on a 4/3 camera as a comparison.It should display all faults that the lens in this thread is claimed not to display.
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Unless I'm mistaken, that's an SLR lens and it won't show the colour shifting issues. The problem is with lenses whose exit element lies close to the sensor, where light comes out at an acute angle.
 
Matthieu said:
Unless I'm mistaken, that's an SLR lens and it won't show the colour shifting issues. The problem is with lenses whose exit element lies close to the sensor, where light comes out at an acute angle.
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I use mostly SLR lenses on my EP-2. The 7.5mm lens is an SLR lens. This lens seems to be soft and not sharp on a digital camera. Maybe it is more apparent that it is not sharp. It is OK on film.
 
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Hi John, good test, I think a bit of shift on the sides, corners, and a bit on the bottom are there, in addition to vignetting, but am just viewing on an uncalib. monitor with the brightness up.

However, it's barely noticeable to me, and for my purposes, I would not muck around with cornerfix or anything, if in fact there is color shift (sure your house siding isn't just a little dirty? ;) )
 
The fact that people use legacy lenses on the NEX series was something of a surprise to Sony.
They have admitted this.

The last few trade shows however had them showcasing the NEX-5 with some legacy lenses.

The Nex 5 and 7 having EVF's now ( better late than never ) makes me think they're now actively seeking that market.

It's logical then that they adress the major shortcomings of the NEX series to use those RF lenses.
 
The sensor in the M9 is made by Kodak. Sony makes its own sensors and supplies them to the majority of camera manufacturers, including Nikon. Canon makes their own sensors as well.
 
Hatch said:
It's logical then that they adress the major shortcomings of the NEX series to use those RF lenses.
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Well, they may do so out of sheer niceness and to build up reputation, but hardly because they hope that RF lenses might fill the gaps in their lens portfolio - they've added a PD AF α-mount adapter for that, and if that isn't enough they'll have higher hopes for SLR mount adapters than RF mount adapters.

The NEX are mass products, in all probability not even profitable until they outsell the number of rangefinder lenses ever made. And the average buyer may have access to some brand SLR lenses, whether from a previous camera or as hand-me-downs within family and friends, but he won't own (or ever have seen) a RF lens.
 
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