Tuesday, August 27, 2019

Pictorial Photography ~ three yearbooks

Back in the day, a certain Clarence H. White was a leading light in the area of photography as art.  His influence can't be understated.

Yet within the photographic culture we remember little to nothing about him.  Stieglitz?  Yes.  Weston?  Yes.  Other practioners?  Not so much.

I have the strange sensation that since "pictorial" photography was practically outlawed by Edward Steichen after seeing the light (pun intended), many photographers and their work have been largely forgotten.

So it was something of a surprise to see on the Gutenberg Press that they have three year books edited by White that are available for free download.

If you are interested in pictorialism in photography, or soft focus lenses, or late-19c tools, materials, and techniques, or photographic history these might be worth a look.

Paris Doux

Tuesday, July 16, 2019

Paris Exhibition ~ Sally Mann until 22 September 2019

Sally Mann has a beautiful show running at the Jeu de Paume in Paris just now.

My wife and I went last Sunday to see it just after the Bastille Day celebrations were finished (the museum didn't open until 13h30 that day).

The crowds were small-ish, though it was difficult to move freely through the first couple of rooms of the exhibit.  But once well inside the show there were fewer people and we could enjoy taking our time to look at the photographs.

My gawd! those photos can be beautiful.  It was a real joy to see deep, richly printed black and white images.  We found Sally Mann's work to be very expressive and deeply moving.

In general, I think the French have a difficult time understanding and appreciating the large landscape works of someone like Ansel Adams.  Those works tend to be remote and cold and people aren't real sure how these can be appreciated.

Certain West Coast photographers like Edward Weston are more approachable for the French.  And if I understand correctly, it has to do with his bohemian lifestyle (he reportedly had many lovers), his images of people and more personal subjects and his political sensibilities (he spent time in Mexico around the edges of the Communist movement).

From the number of shows we see listed here in Paris, the French embrace American street photographers, mainly from New York.  And they really appreciate good American photographers who make Paris their home, like Peter Turnley.

So it was interesting to us to see how the French reacted to Sally Mann.  Her work is not as literal as some people might be used to.  Listening to the French as they talked through the show was fascinating.  Some marveled at the optical effects that create smooth out of focus background renditions.  Some people were taken by the beauty of Sally's subjects (and my gawd! can her subjects be beautiful).  And others were surprised by how slavery in America continues to impact culture and society there and how this history could be so accurately portrayed in an artistic work.

For me the exhibit worked well on two levels.  The first is that her work is inspirational.  Sally Mann has found a way to use the tools of photography to express the various themes she explores in a way that transcends the tools in the creation of her works of art.

The second level is more profound.  Much is made about race relations in America.  After seeing the show I can't help but feel a deep sadness for terrible things in American history that continue to influence the present.

Sunday, June 16, 2019

Nikon Micro-Nikkor, Nikkor 105mm lenses ~ a closer look

Recently I picked up a Nikon Micro-Nikkor 105mm f/4 P Ai lens, thinking and hoping that it's out of focus rendition would be similar to the 55mm Micro-Nikkor lenses I have.  Someone on the 'net suggested that the 105mm Micro-Nikkor f/4 is "wickedly" sharp from wide open.  So this blog entry takes a look at this and compares its resolution with three other 105mm Nikkor lenses I have on hand.

Setup -
  • Sony A6000, 100ISO, 2 second delay timer, RawTherapee conversion software 
  • Big Beefy Manfrotto tripod 
  • Lenses compared
    • Nikon Micro-Nikkor 105mm f/4 P Ai
    • Nikon Nikkor 105mm f/2.5 P pre-Ai
    • Nikon Nikkor 105mm f/2.5 Ai
    • Nikon Nikkor 35mm to 105mm f/3.5 to f/4.5 AiS zoom at 105mm
  • Lens Turbo II focal length reducer
Note:
It's become obvious to me over the years that nearly all lenses suffer from field curvature.  Some lenses, as we might expect, have more pronounced curved fields than others.  So to account for this, I have taken to shooting two images at each comparison aperture.  The first image is focused in the center of the field, and the second image focuses at the very edge of the field of view.  It is important to note that I'm not attempting to measure how much field curvature there is.  All I'm looking at is, at the edge of the field, how sharp the optic is.  If one photographs flat subject matter, nearly all lens will be more or less out of focus at the edge of the field.

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 105mm Comparison


Comments -

Comparing the Nikon Micro-Nikkor 105mm f/4 P Ai to the Nikon Nikkor 105mm f/2.5 and f/4.5 zoom, I see that wide open the f/4 Micro-Nikkor lens is indeed quite sharp, though I might not call it "wickedly" sharp.  Focusing at the edges of the frame I see that the Micro-Nikkor is slightly less sharp wide open than the center, but that this cleans up very nicely as the aperture is stopped down.  As for field curvature (which I am not in any measuring, but simply noting), the Micro-Nikkor suffers from a small amount where the 55mm Micro-Nikkors I looked at do not.  I appears to me that to have a perfectly sharp image across a flat field that a user will need to stop down a click or two from wide open.

Looking at the 105mm f/2.5 P and Ai lenses I see that both are sharp in the center wide open.  In the corners, too, the non-Ai P 105mm appears to match the 105mm f/2.5 Ai.  Though it could be noted that field curvature of the early P non-Ai lens stronger than the updated design Ai.  Compared with the Micro-Nikkor, it is difficult to tell a difference when curvature is accounted for in resolution between them across the field.  The only note would be that field curvature is less with the Micro-Nikkor than it's f/2.5 brothers.

Lastly, I took a look at a Nikon Nikkor 35mm-105mm f/3.5-f/4.5 AiS zoom at 105mm.  Wide open resolution suffers across the field.  Stopped down to f/5.6, however, the lens looks quite good in the center and matches the three fixed focal length 105mm lenses here.  At the edges the zoom's resolution appears to clean up rather nicely at f/8.  Regarding field curvature, of the four lenses looked at here this zoom shows the most curvature.  The curvature is quite dramatic, actually.

Saturday, June 15, 2019

Nikon Nikkor 85mm f/1.8 and f/2 lenses ~ a closer look

It so happens that I picked up another Nikon Nikkor 85mm f/2 Ai lens.  I owned one when I moved here, sold it, and got to wondering how it compared to my other, older 85mm f/1.8 K pre-Ai.  So here is yet another look at how they compare from a resolution point of view.

Setup -
  • Sony A6000, 100ISO, 2 second delay timer, RawTherapee conversion software 
  • Big Beefy Manfrotto tripod 
  • Lenses compared
    • Nikon Nikkor 85mm f/1.8 K pre-Ai
    • Nikon Nikkor 85mm f/2 Ai
  • Lens Turbo II focal length reducer
Note:
It's become obvious to me over the years that nearly all lenses suffer from field curvature.  Some lenses, as we might expect, have more pronounced curved fields than others.  So to account for this, I have taken to shooting two images at each comparison aperture.  The first image is focused in the center of the field, and the second image focuses at the very edge of the field of view.  It is important to note that I'm not attempting to measure how much field curvature there is.  All I'm looking at is, at the edge of the field, how sharp the optic is.  If one photographs flat subject matter, nearly all lens will be more or less out of focus at the edge of the field.

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 85mm Comparison


Comments -

Comparing the Nikon Nikkor 85mm f/1.8 K pre-Ai to the Nikon Nikkor 85mm f/2 Ai, I see that wide open the early f/1.8 lens is slightly less sharp than the newer design f/2 Ai.  At the edges of the frame, the f/1.8 K pre-Ai lens clearly lags the f/2 Ai.  Yet both lenses sharpen up very nice from f/4, and from f/4 on down the aperture range both lenses appear to be equal in the center and edges of the frame.

In terms of field curvature, I see that the f/1.8 K pre-Ai suffers from greater field curvature than the newer f/2 Ai optic (remember, I'm not trying to measure the field curvature, only noting the curvature in relative terms).

Since I don't sharpen the comparison images in any way, I thought it might be interesting to see what a rather aggressive unsharp mask might do to images from both lenses at wide open and f/2.8 in the center and at the edges.  The USM was set to a 2 pixel radius and a 0.5 contrast step.  This is pretty steep and I normally put the USM image in a separate layer and adjust its opacity over the original image to balance the harshness of the USM to make the final image more "film-like" (I feel some of the software tools can make an image appear "artificial" and cell-phone-like).

In both cases, the USM makes the wide open and f/2.8 images appear sharper than their f/4 to f/8 non-USM equivalents on the two lenses.  The f/1.8 K pre-Ai lens still lags the f/2 Ai wide open.  But, this shows what is possible if one wants to clean up an image that was shot at the widest aperture.  The results can be pretty darned impressive.

Monday, June 03, 2019

Nikon Nikkor 85mm f/2 and f/1.8 ~ point light source comparison


For many years I looked at just one dimension of commercially available optics - resolution.  With this blog entry I continue to look at other aspects of optical performance.  For the series of postings 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
  • Big Beefy Manfrotto tripod
  • Lenses using with a Lens Turbo II focal reducer -
    • Nikon Nikkor 85mm f/2 Ai
    • Nikon Nikkor 85mm f/1.8 K pre-Ai
  • 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.

Nikon Nikkor 85mm lenses ~ Point Light Source Comparison


Comments -

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

The Nikon Nikkor 85mm f/2 Ai lens shows under corrected spherical aberration as well as a bright edge ring that suggests over correction around the outside of the out of focus disk.  In normal use, I expect the out of focus rendition to be "harsher" than, say, the next lens from Nikon.
The Nikon Nikkor 85mm f/1.8 K pre-Ai lens shows classic under corrected spherical aberration with a bright dot in the center of a smooth disk.  In normal use, I expect the out of focus rendition to be "delicate" (using Nikon's own description of the effect) and smooth across the field.


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

Monday, May 27, 2019

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.

Nikon Nikkor 105mm Point Lightsource Comparison


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

Sunday, May 26, 2019

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.

Nikon Nikkor 28mm Point Lightsource Comparison


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