Sigma 24mm f/3.5 DG DN, Nikon Nikkor 24mm f/2.8 Ai comparison

Well, I did it.  I purchased an AF 24mm lens.  It's a Sigma 24mm f/3.5 DG DN for Sony E.  It's a pretty little thing.

There are plenty of comprehensive reviews that look at the Sigma, so I will limit myself to comparing French political newspaper photos between the new lens and  my old Nikon Nikkor 24mm f/2.8 Ai.  

I'm getting old.  Redundancy tends to confuse me.  For example, at one point I had 5 different 105mm Nikkors.  Which to use?  It was seldom an easy answer.  Perhaps the best answer for me is to simplify.  That leaves the current question - do I sell the Nikon now that I have the Sigma? 

Setup ~ 

• Camera - 
• Sony A7, 100ISO, 2sec timer, "A" mode
  
• Lenses - 
• Sigma 24mm f/3.5 DG DN
  
• Nikon Nikkor 24mm f/2.8 Ai
  
• Bogen tripod
  

• RawTherapee -
• Snug up the curves
• With and without "Capture Sharpen" 
• Automated chromatic aberration correction on the Nikkor
  

 

Comparison ~

As always, click on the image and enlarge to 100percent to see whatever there is to be seen.

 

 

Comments ~

Previously I realized that the corners of the Nikon Nikkor 24mm f/2.8 Ai could clean up rather nicely by using a little Rawtherapee Chromatic Aberration correction.  I originally found a manual way of doing this and had set the sliders to +0.004 to get a good clean image all the way into the corners.  

 

While preparing this comparison I'd forgotten where the manual sliders were and stumbled across an automated function.  So I tried that this time around and, well, the results are about the same as what I'd performed manually.  Maybe my eyes aren't as bad as I think they are?

Looking at the center of the field, there's not much difference between the Sigma and the 40 year old Nikkor.  If I stare intently enough, I can see that the Sigma appears to be slightly sharper.

 

On the other hand the Nikkor gives a nice "meaty" sense of resolution.  I'll say more about this in another post, but this kind of "sharpness" is what I see in my new Sony ZA 35mm and 55mm lenses, as well as nearly every single Nikon Nikkor I've ever looked at.  There's something in common going on, here.  I suspect is has to do with optical design philosophies.

Considering the edges, there are three things that I see.  First, the Sigma is behaving like a very nice Flat Field lens.  It's sharp clear across the field into the corners.  As with before, the Nikkor corners clean up well by f/5.6 where it begins to look very "current" in it's rendition.

 

The second thing I see is that the Rawtherapee Chromatic Aberration correction works nicely on the Nikkor.  It's nice to note that this correction is not at all needed/useful with the Sigma.  The Sigma is beautiful in this regard where the Nikon benefits from a little (not much, really) help.

The third thing I see in the corners is that there is a bit more distortion in the Sigma than there is in the Nikkor.  The Nikkor looks quite "neutral" where the Sigma "pulls" a bit.  If I didn't have these side by side I'm not sure I'd notice much of anything.  But since we're here, I thought I'd better say something about it.

 

So where does this leave me?  We'll see, but I'm leaning toward selling the Nikon lens so someone else can benefit from its beautiful performance.