Saturday, June 30, 2018

Comparison ~ Nikon Micro-Nikkor 55mm f/3.5 pre-Ai and f/2.8 Ai

The insanity continues.

A friend recently sent me his old Nikon Micro-Nikkor 55mm f/2.8 Ai.  I already had a copy of the earlier lens, a 55mm f/3.5 pre-Ai.

Playing around, I took a look at how well these worked with a 52mm threaded reverse adapter that flips the lens around on a camera.  I learned that the adapter worked best when the subject to lens distance was shorter than the focal length (otherwise the edges went soft very quickly).  But for everything else macro a normally oriented lens worked best.

In general use, I couldn't help but notice the f/3.5 "felt" sharper wide open than the f/2.8 at f/2.8.  But stopped down, everything was brilliantly sharp out of both lenses.

Macro is not what I do, but, still playing around and wondering about "things" I thought it might be fun to see how the two Micro-Nikkor lenses behaved at 1:2 magnification (as marked on each lens).

Setup -
  • Sony NEX-5T, 100ISO, AWR converted in Sony's software 
  • Big Beefy Manfrotto tripod 
  • Nikon Micro-Nikkor 55mm f/2.8 Ai
  • Nikon Micro-Nikkor 55mm f/3.5 pre-Ai 

Comparison Results -

[If you click on the image it'll take you to the Flickr hosting site. Once there, look at the file at full resolution. In many cases the differences between lenses is small and likely can't be seen until you take a squint at the comparison at 100 percent.]

Nikon 55mm f/2.8 and f/3.5 Micro-Nikkor Comparisonf28f35


Comments -

Indeed, the Micro-Nikkor 55mm f/2.8 shot at f/2.8 is softer than it's brother lens shot at f/3.5.  The difference isn't that great, but it is noticeable (otherwise why comment on it, right?). 

However, the f/2.8 lens at f/4 is sharper than the f/3.5 at f/3.5.

From f/5.6 on down both lenses look nearly identical.

One of the things I like about shooting with a Micro-Nikkor is that the image field is flat and without distortion.  Images can be sharp all the way to the edge and I don't have to apply pincushion/barrel distortion corrections.  As a bonus, the out of focus rendition of both lenses shot wide open is very smooth and creamy.  I like this since many 50-58mm lenses suffer from over corrected out of focus regions which leads to "soap bubble bokeh".

I suppose I should, for completeness, take a look at how both lenses compare at more normal photography working distances.

Friday, June 29, 2018

Fungus ~ Nikon Nikkor 300mm f/4.5 pre-Ai before/after CLA

It so happened that I picked up a cheap 300mm Nikon Nikkor f/4.5.  After receiving the package I realized why it was so cheap.  Here was a second opportunity to see how fungus could affect image rendition.  This time the lens was pretty clouded with champignons.  The inside forward elements were covered with nastiness.  And it looked like the inside and outside of the rear element set hadn't ever been cleaned.

Setup -
  • Sony A6000, 100ISO, AWR converted in Sony's software 
  • Big Beefy Manfrotto tripod 
  • Nikon Nikkor 300mm f/4.5 pre-Ai with very very light scratches on the front element (as the control optic)
  • Nikon Nikkor 300mm f/4.5 pre-Ai filled with fungus (before CLA) and cleaned (somewhat)
  • Lens Turbo II adapter

Comparison Results -
[If you click on the image it'll take you to the Flickr hosting site. Once there, look at the file at full resolution. In many cases the differences between lenses is small and likely can't be seen until you take a squint at the comparison at 100 percent.]

Nikon Nikkor 300mm f/4.5 pre-Ai


Comments -

The control optic is a fine lens.  Sharp from wide open, this lens, even with the light scratches, is contrasty and just plain downright good.

The fungus infected 300mm did indeed show performance degradation.  This really is no surprise.  There was so much gunk and crud that just about any amount of cleaning would've done the lens good.  And it did.

However, the CLA'd lens still suffers for a very slight lack of contrast.  A re-inspection of the lens revealed that the inside of the rear element set is a little cloudy.  The way Nikon manufactured these lenses makes it difficult to disassemble.  The various threaded retainers tend to be nearly impossible to remove.  So... I'm not sure what to do with the lens... perhaps I'll sell it as is?

Wednesday, June 27, 2018

Fungus ~ Nikon Nikkor 35-105mm f/3.5-f/4.5 zoom before/after

I wanted to see what effects fungus infected lens elements might have on resolution and contrast.  On hand was a Nikon Nikkor 35-105mm f/3.5-f/4.5 zoom that was somewhat infected.  It wasn't too bad, but still, I thought even a little should affect the outcome.

Setup -
  • Sony A6000, 100ISO, AWR converted in Sony's software 
  • Big Beefy Manfrotto tripod 
  • Nikon Nikkor 35-105mm f/3.5-f/4.5 zoom
    • Straight-thru adapter
    • Lens Turbo II adapter
Fungus -

Here's a look at what fungus there was in the lens before a proper CLA.

Nikon Nikkor 35mm to 105mm f/3.5-4.5


Comparison Results -

[If you click on the image it'll take you to the Flickr hosting site. Once there, look at the file at full resolution. In many cases the differences between lenses is small and likely can't be seen until you take a squint at the comparison at 100 percent.]

Nikon Nikkor 35mm to 105mm f/3.5-4.5


Comments -

There's not much to say.  I can't tell any difference between the pre and post-CLA'd lens output.  This is a case where fungus had little to no effect on image creation.

Friday, June 08, 2018

David Douglas Duncan

Gods!

David Douglas Duncan has died.

I grew up with DDDuncan's images.  I well remember his work in the '60's from Vietnam.  I well remember his other images, too.  He was one of the Greats against whom so much was measured.

It is because of him that I chase, buy, and use old wonderful Nikon Nikkor optics.



Friday, June 01, 2018

Comparing a strange mix of optics

... once more again into the abyss, shall we?

Today I would like to take a look at a rather odd mix of lenses.

Two lenses offer fields of view that are much greater than the usual 35mm Full Frame format.  They are Nikon's original perspective control lenses.  These are traditionally used for keeping vertical lines and perspective when photographing building interiors and exteriors "correct" by shifting the lens.

Two of the other lenses are new to the Toy Box. It is an old Nikon Nikkor 105mm f/2.5 P pre-ai (the one with the small rear elements.   The other new Toy Box lens is a Nikon Micro-Nikkor 55mm f/2.8.  A good friend sent me these lenses as well as the 35mm PC.

One of the Nikkor lenses was part of the Super Deal that I scored off eBay point fr that set me back all of 7 Euro.  For an old somewhat thrashed 50mm lens, this one seems to tickle one of many funny bones I seem to have.

Lastly, I wanted to take another look at the Zeiss Jena DDR 50mm Tessar.  I couldn't believe that it performed as poorly as it did in the first test.  So I wanted another go at it to see if in reassembly I might have aligned things a little better this time.

Setup 
  • Sony A6000, 100ISO, AWR converted in Sony's software 
  • Big Beefy Manfrotto tripod 
  • Lenses - 
    • Nikon Nikkor 28mm f/3.5 PC  - shot straight on, no shift
    • Nikon Nikkor 35mm f/2.8 PC - shot straight on, no shift
    • Nikon Nikkor 50mm f/2 Ai  
    • Nikon Micro-Nikkor 55mm f/2.8 Ai 
    • Zeiss Jena DDR 50mm f/2.8 Tessar "pancake" in m42 mount 
The perspective control lenses were shot on a Lens Turbo II focal reducer adapter.  I wanted to see what the performance would be across the field.

The other lenses were shot using "straight through" adapters. So what we will observe there is full frame lens performance on APS-C sized/cropped sensors. This means the very outer limits of the field of view will not be compared at all. If something already performs poorly at the outer edges of the APS-C frame, it will very likely be pretty horrible at the far edges of the full frame 35mm format.

Comparison

[If you click on the image it'll take you to the Flickr hosting site. Once there, look at the file at full resolution. In many cases the differences between lenses is small and likely can't be seen until you take a squint at the comparison at 100 percent.]

Nikon 28mm, 35mm PC, 50mm Zeiss Comparison

Comments

To begin with, the Nikon Nikkor 28mm f/3.5 PC is absolutely brilliant.  It's sharp across the field and all the way out to the edge of the focal reduced frame.  If I didn't know any better I'd say I was shooting the equally wonderfully sharp 28mm f/3.5 Ai Nikkor that I have. 

After seeing these results I'm happy haven't sold this PC lens.  It's been up for sale for the past several years, but no one has ever enquired about it.  Sale prices have dropped pretty dramatically, too, from the days when these were moving for north of 500USD.  No, this is being taken off the market and it now stays in the kit.

The second perspective control lens I own, the 35mm PC, is ever so slightly soft wide open.  The edges, too, seem to be slightly softer than it's 28mm PC sister.  Stopped down things improve across the field.  When shooting architecture and using the shift capability I see I should shoot the lens at f/8 or f/11 to make sure the outer edges are kept as sharp as possible.

Coming to one of the lenses that really tickles my many funny bones is the 7Euro Nikkor 50mm f/2 Ai.  It's acceptably sharp wide open and becomes wickedly sharp one click down at f/2.8.  This lens has seen a rough life and there is a mark on the rear element.  But none of this seems to matter.  It's just plain sharp sharp sharp.  Period.

If you've been following along with some of my other comparisons you'll know I have a Micro-Nikkor 55mm f/3.5 non-Ai.  That lens is wickedly sharp from wide open.  By comparison, the f/2.8 example seen here is ever so slightly softer wide open than the older f/3.5.  It's nothing that can't easily be resolved using a bit of smart sharpen in processing. 

Still, it surprised me a little as I'd read and heard that the f/2.8 version was "better"than the f/3.5.  Now I'm wondering by what measure the f/2.8 is supposed to be "better."  Stopped down, of course, the f/2.8 and f/3.5 are indistinguishable from each other.  Both are wonderful lenses... and... now that I've gone looking for comparison results from the 55mm f/3.5... I can't seem to find them... which means I have yet another opportunity to compare lenses.  Oh boy!

Lastly, the dreaded Zeiss Jena DDR 50mm f/2.8 Tessar performance hasn't changed.  For this comparison I stopped all the test samples down to f/8.  It's there (at f/8) that the center of the Tessar finally equals the resolution of the other lenses.  This is very strange to me as Zeiss has a strong reputation for performance. 

Perhaps Zeiss failed to wave their Magic Resolution Performance Wand over this design?  Every single copy of the Zeiss Tessar I've had has tested the very same way, and I've owned early and late examples of the little lens.  On the other hand, I've heard some people say they don't care about any of that, but instead enjoy the Tessar's ability to produce strong "bubble bokeh" in the out of focus regions when shot wide open.