Nikon Micro-Nikkor, Nikkor 105mm ~ point light source comparison

For many years I looked at just one dimension of commercially available optics - resolution.  Now I continue to look at other aspects of optical performance.  For this series I look at under, neutral, and over corrected spherical aberration in out of focus rendition on subject matter behind the point of focus.

Setup -

• Sony NEX5T, ISO 100, 2 second timer, +1 EV
• Big Beefy Manfrotto tripod
• Lenses using with a Lens Turbo II focal reducer -
• Nikon Micro-Nikkor 105mm f/4 Ai
• Nikon Nikkor 105mm f/2.5 P pre-Ai (early Sonnar design)
• Nikon Nikkor 105mm f/2.5 Ai (later modified Sonnar, slightly more symmetrical design)
• NOTE1: Lenses were shot at their widest apertures only
• NOTE2: Out of focus samples are from points _behind_ the point of focus to compare background out of focus rendition
• RawTherapee to convert RAW files into black and white and to set the black levels

  Comparison -

If you click on the following image you can inspect it at 100 percent.



Comments -

NOTE: I feel the Lens Turbo II focal reducer adds a bit of under-corrected spherical aberration.

 I had expected the Micro-Nikkor to show similar neutral very smooth out of focus rendition to the pair of 55mm Micro-Nikkors I looked at.  Alas, this is not the case.

These three Nikon Nikkor, Micro-Nikkor 105mm f/4 and f/2.5 P pre-Ai and Ai lenses show under corrected spherical aberrations.  At the point of focus, the Micro-Nikkor is one of the sharpest lenses I've looked at.  But that's not what this comparison is about.

In normal photography I would expect, based on these comparisons, that there will be a very smooth and delicate (to use Nikon's own word on the topic) out of focus field rendition, with the f/4 Micro-Nikkor showing a stronger "condom ring" (which will contribute to a distracting out of focus rendition) than the two f/2.5 lenses (compare the smooth, rounded edges of the out of focus disks of the f/2.5 lenses against the sharp edged disks of the Micro-Nikkor).


Resources -

For further information on how the topic of out of focus rendition, optical properties, and Nikon lens design history, please refer to the following -

A PhD thesis on the impact of "soft focus" lenses on the history of photography - http://research-repository.st-andrews.ac.uk/handle/10023/505

An excellent starting point for understanding out of focus rendition (I might not completely agree with his interpretations/observations, but his foundation of understanding is quite good) - http://jtra.cz/stuff/essays/bokeh/

Nikon lens design histories - https://imaging.nikon.com/history/story/

Point light source discussions - https://www.dpreview.com/forums/thread/4031515

Zeiss comments on optical design -  https://lenspire.zeiss.com/photo/en/article/how-does-zeiss-define-bokeh-an-interview-with-dr-stefan-ballmann

Metabones Focal Reducer whitepaper - https://www.metabones.com/assets/a/stories/Speed%20Booster%20White%20Paper.pdf

Nikon Nikkor 28mm lenses ~ point light source comparison

Returning home after passing a winter in the south I am inspired to continue my look into point light source in-focus, out of focus comparisons.

Setup -

• Sony NEX5T, ISO 100, 2 second timer, +1 EV
• Big Beefy Manfrotto tripod
• Nikon lenses using with a Lens Turbo II focal reducer -
• Nikon Nikkor 28mm f/2.8 Ai
• Nikon Nikkor 28mm f/3.5 H pre-Ai
• Nikon Nikkor 28mm f/3.5 PC
• NOTE1: Lenses were shot at their widest apertures only
• NOTE2: Out of focus samples are from points _behind_ the point of focus to compare background out of focus rendition
• RawTherapee to convert RAW files into black and white and to set the black levels

  Comparison -

If you click on the following image you can inspect it at 100 percent.



Comments -

NOTE: I feel the Lens Turbo II focal reducer adds a bit of under-corrected spherical aberration.

The Nikon Nikkor 28mm f/2.8 Ai shows under-corrected spherical aberrations with just a moderately strong bright ring around the edge of the image circle.  In normal photography I would expect, based on these comparisons, that there will be a hint of a "busy" rendition in a smooth, delicate out of focus field.

The Nikon Nikkor 28mm f/3.5 H shows stronger over-corrected spherical aberration with a fairly bright edge ring on out of focus disks.  The center, as with it's brother lens the f/2.8, shows under-corrected spherical aberration.  In normal photography I would expect, based on these comparisons, that there will be a somewhat confusing rendition of the out of focus field, mixing the two aberration types as this lens does.

The Nikon Nikkor 28mm f/3.5 PC (perspective control) lens shows moderate under-corrected spherical aberration with a hint of a bright ring around the edge of the out of focus disk.  In normal photography I would expect the lens to be a hint of a "busy" field against a smooth, delicate out of focus rendition.


Resources -

For further information on how the topic of out of focus rendition, optical properties, and Nikon lens design history, please refer to the following -

A PhD thesis on the impact of "soft focus" lenses on the history of photography - http://research-repository.st-andrews.ac.uk/handle/10023/505

An excellent starting point for understanding out of focus rendition (I might not completely agree with his interpretations/observations, but his foundation of understanding is quite good) - http://jtra.cz/stuff/essays/bokeh/

Nikon lens design histories - https://imaging.nikon.com/history/story/

Point light source discussions - https://www.dpreview.com/forums/thread/4031515

Zeiss comments on optical design -  https://lenspire.zeiss.com/photo/en/article/how-does-zeiss-define-bokeh-an-interview-with-dr-stefan-ballmann

Metabones Focal Reducer whitepaper - https://www.metabones.com/assets/a/stories/Speed%20Booster%20White%20Paper.pdf

Sigma 19mm, 30mm, Sony 50mm ~ point light source comparison

Having looked at the out of focus rendition of vintage Nikon lenses, I wanted to see what, if anything, had changed over the years of optical design and look at three current lenses.

Setup -

• Sony NEX5T, ISO 100, 2 second timer, +1 EV
• Big Beefy Manfrotto tripod
• Lenses designed for Sony E-mount APS-C cameras -
• Sigma 19mm f/2.8 EX DN E
• Sigma 30mm f/2.8 EX DN E
• Sony 50mm f/1.8 SEL OSS
• NOTE1: Lenses were shot at their widest apertures only
• NOTE2: Out of focus samples are from points _behind_ the point of focus to compare background out of focus rendition
• RawTherapee to convert RAW files into black and white and to set the black levels

  Comparison -

If you click on the following image you can inspect it at 100 percent.



Comments -

The Sigma 19mm f/2.8 EX DN E out of focus rendition confuses me.  There is a slight bright ring around the out of focus disk, along with a bright center with a dark whole in the middle.  The further out of focus the point, the more "choppy" the disk becomes.  Concentric circles form the farther out of focus the disk becomes.

The Sigma 30mm f/2.8 EX DN E out of focus rendition confuses me just like the 19mm Sigma does.  There is a bright outter ring to the disk, followed by a brighter center with a dark hole in the middle.  The "choppy" field effect across the disk is less than with the 19mm, but it's still clearly visible.

The Sony 50mm f/1.8 SEL OSS starts out having a nice smooth disk with a brighter center just like the lens is under-corrected.  But the further out of focus the point is, the stronger the outter ring becomes.  It's as if the Sony lens is both under and over-corrected.


Resources -

For further information on how the topic of out of focus rendition, optical properties, and Nikon lens design history, please refer to the following -

A PhD thesis on the impact of "soft focus" lenses on the history of photography - http://research-repository.st-andrews.ac.uk/handle/10023/505

An excellent starting point for understanding out of focus rendition (I might not completely agree with his interpretations/observations, but his foundation of understanding is quite good) - http://jtra.cz/stuff/essays/bokeh/

Nikon lens design histories - https://imaging.nikon.com/history/story/

Point light source discussions - https://www.dpreview.com/forums/thread/4031515

Zeiss comments on optical design -  https://lenspire.zeiss.com/photo/en/article/how-does-zeiss-define-bokeh-an-interview-with-dr-stefan-ballmann

Metabones Focal Reducer whitepaper - https://www.metabones.com/assets/a/stories/Speed%20Booster%20White%20Paper.pdf

Nikon Nikkor 100mm to 300mm lenses ~ a closer look

It so happens that I picked up a rather inexpensive (supposedly in need of repair, but in reality didn't need any such thing) 100-300mm Nikon Nikkor f/5.6 AiS.

I've recently been impressed by the Nikon 75-150mm E-series (yes! it's true) and the Nikkor 80-200mm f/4.5 N Ai zoom lenses.  None of the more modern Canon EOS zoom lenses were ever this close to being wonderfully razor sharp at the point of focus and creamy smooth in the out of focus regions.  So when this 100-300mm AiS Nikkor came along for so little money, I had to have a look at it's performance.

Setup -

• Sony A6000, 100ISO, 2 second delay timer, RawTherapee conversion software 
• Big Beefy Manfrotto tripod 
• Lenses compared
• Nikon Nikkor 105mm f/2.5 Ai
• Nikon Nikkor 135mm f/3.5 Ai
• Super-Takumar 200mm f/4
• Nikon Nikkor 300mm f/4.5 pre-Ai 
• Nikon Nikkor 100-300mm f/5.6 AiS 
• compared at 100mm
• 135mm
• 200mm
• 300mm
• Lens Turbo II adapter with the Nikkors, but not the Takumar

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.]



Comments -

Comparing the Nikon Nikkor 100-300mm f/5.6 AiS to a Nikon Nikkor 105mm f/2.5 Ai, I see that both the 105mm and 100-300mm lenses are both very sharp in the center of the frame.  At the edges, the 100-300mm lens remains very sharp.  It appears the 105mm f/2.5 Ai suffers from a bit of field curvature as the edges of the frame are clearly not as sharp as the zoom on this 2D subject.

Comparing the Nikon Nikkor 100-300mm f/5.6 AiS to a Nikon Nikkor 135mm f/3.5 Ai, I see that both the 135mm and 100-300mm lenses are very sharp in the center of the frame.  At the edges, the 135mm lens remains very sharp, with the 100-300mm lens trailing ever so slightly in terms of absolute resolution.

Comparing the Nikon Nikkor 100-300mm f/5.6 AiS to a Super-Takumar 200mm f/4 M42 lens, I see that the 200mm is very slightly sharper than the 100-300mm lens in the center of the frame.  At the edges, the 200mm lens is very slightly less sharp than the 100-300mm lens.

Comparing the Nikon Nikkor 100-300mm f/5.6 AiS to a Nikon Nikkor 300mm f/4.5 pre-Ai, I see that the 100-300mm lens is very sharp straight across the field.  The fixed focal length 300mm f/4.5 lens is clearly behind the zoom in terms of resolution.

Overall, the Nikon Nikkor 100-300mm f/5.6 AiS lens is truly outstanding at f/5.6 (which is wide open with this optic) and f/8.  In the center it can keep up with the fixed focal length lenses I compared this zoom to.  The optic's field is surprisingly flat and exceeds three of the four fixed focal length lenses in terms of flat field resolution at the extreme edges of the frame.

So, how much did this super sharp wonder zoom set me back?   30Euros.

Nikon Nikkor 100-300mm f/5.6 Ai ~ point light source comparison

For many years I looked at just one dimension of commercially available optics - resolution.  Now I wanted to start looking at other aspects of optical performance.  For this series I look at spherical aberration (looking for under, neutral, or over correction) in out of focus rendition on subject matter behind the point of focus.

Setup -

• Sony A6000, ISO 100, 2 second timer
• Big Beefy Manfrotto tripod
• Lens using with a Lens Turbo II focal reducer -
• Nikon Nikkor 100-300mm f/5.6 Ai zoom

• NOTE1: Lens was shot at the widest aperture only
• NOTE2: Out of focus samples are from points _behind_ the point of focus to compare background out of focus rendition
• RawTherapee to convert RAW files into black and white and to set the black levels

 Comparison -

If you click on the following image you can inspect it at 100 percent.



Comments -

NOTE: I feel the Lens Turbo II focal reducer adds a bit of under-corrected spherical aberration.

The Nikon Nikkor 100-300mm f/5.6 Ai zoom at 100mm shows a flat out of focus disk.  The further out of focus a dot becomes, the more a slight under-corrected spherical aberration in the out of focus regions is revealed.  Based on this comparison, in normal photographic use this lens at this focal length should produce a smooth out of focus rendition.

At 200mm, this Ai zoom continues to show a flat neutral disk.  The further out of focus a dot becomes, the more a slight under-corrected spherical aberration in the out of focus regions is revealed.  Under normal photographic conditions I would expect that this lens at 200mm will continue to show a smooth out of focus rendition.

At 300mm, this Ai zoom shows very neutral out of focus rendition.  Under normal photographic conditions I would expect this lens at this focal length to produce extremely smooth out of focus rendition.


Resources -

For further information on how the topic of out of focus rendition, optical properties, and Nikon lens design history, please refer to the following -

A PhD thesis on the impact of "soft focus" lenses on the history of photography - http://research-repository.st-andrews.ac.uk/handle/10023/505

An excellent starting point for understanding out of focus rendition (I might not completely agree with his interpretations/observations, but his foundation of understanding is quite good) - http://jtra.cz/stuff/essays/bokeh/

Nikon lens design histories - https://imaging.nikon.com/history/story/

Point light source discussions - https://www.dpreview.com/forums/thread/4031515

Zeiss comments on optical design -  https://lenspire.zeiss.com/photo/en/article/how-does-zeiss-define-bokeh-an-interview-with-dr-stefan-ballmann

Metabones Focal Reducer whitepaper - https://www.metabones.com/assets/a/stories/Speed%20Booster%20White%20Paper.pdf