Old vs New ~ Nikon Nikkor-O 35mm f/2 vs Sigma 30mm f/2.8 EX DN E

From a recent post, the Nikon Nikkor-O 35mm f/2 pre-Ai looks pretty good, regardless of age.  For me an obvious question is how it compares with current day computer design optics?

I have a Sigma 30mm f2.8 EX DN E that is wickedly sharp from f4 on down.  So I mounted the Sigma on my Sony A7 and shot it in full frame mode (no APS-C cropping).  I did this to keep things more or less equal between the newer and old lenses.  All I needed to do was move the tripod to account for the 5mm focal length difference.

Setup - 

• Sony A7 - ISO50, 2 second timer, in-camera levels used to square the whole plot up
• Manfrotto tripod - it's capable of securing an 8x10inch view camera, so it's sturdy enough for this
  
• Lenses -
• Nikon Nikkor-O 35mm f/2 pre-Ai single coated - shot from f/2 through f/8
• Sigma 30mm f/2.8 EX DN E - shot from f/2.8 through f/8 shot Full Frame which shows the edge of the frame clipped due to the lack of FF coverage
• Rawtherapee RAW to jpg conversion - Auto-Match function, but nothing further (ie: NO Capture Sharpening)

Comparison - 

Here is the scene setup.  It's just a pair of closed gaze scrims in our apartment.  The details are interestingly small, so therefore useful for this kind of "wee look-see." 

 

 

[As always, click on the image and look at it to 100percent file size to see whatever there is to be seen.]

 

 

Comments - 

At f/2.8 the Nikkor-O is just a touch softer than the Sigma.  Not by much, mind you, but just enough that I can see it pixel-peeping.

From f/4 on down through f/8 I have a difficult time telling the difference between the 50+ year old Nikkor-O 35mm lens and the 10 year old Sigma 30mm.  In terms of how I "see sharpness", the images are equivalent.

Though I don't show it here, by applying Rawtherapee's "Capture Sharpen" to any of the images, Nikon or Sigma, the "apparent sharpness" will visibly increase.

Coming to subtle differences between how the Nikon and Sigma lenses "render" an image, I found it interesting the way the tree in the background appears to be "softer" and "smoother" with the Nikkor-O than with the Sigma.  I could've predicted this based on earlier comparisons of point light sources out of focus.  Nikkor lenses, historically, have been designed for this kind of smooth out of focus rendition behind the point of focus.

So what, if anything, has been gained in commercial optics between the time of the Nikkor-O seen here and the Sigma Art DN?  Not much optically, maybe.  Additionally, perhaps not all lens manufacturers have Nikon's sensitivity to how the out of focus regions are rendered, either, but, a lot of other closely related things _have_ changed in 40 years.

We now have autofocus, as well as very small, sharp lenses like this little 30mm f/2.8.  It weighs all of 140grams compared with the Nikon 35mm f/2 at one aperture stop wider and 285grams, which comes without autofocus (of course).  

I'm certain that vast improvements have been made in "manufacturability" over the years.  It takes fewer steps to make a lens these days and with higher assembly accuracy (though I have a Sony 16mm f/2.8 SEL that might suggest otherwise).