Wednesday, October 18, 2017

Optical vs Filter "softness"

As I'm still somewhat obsessed with the topic of "softness" and trying to learn what I can, I thought I'd take a look at comparing the optical "softness" rendered by the Pentax 85mm f2.2 SMC Soft to the Nikon Nikkor 50mm f/1.8 AiS and 85mm f/1.8 K pre-Ai with two Nikkor soft filters numbers 1 and 2.

Here is the comparison (as always, follow the link, find the all sizes images, and look at this at 100 percent to see everything there is to see).  Please note that the second to last comparison should read "... Nikkor Soft 1".  The comparison will make more sense.

Pentax Soft and Nikkor Soft Filters

What I see is that the Nikon lenses with the Nikkor soft filters simply add softness to the image, just as we would expect.  The number 2 Soft filter is, again as expected, gives a stronger softness than the number 1 filter.  In terms of softness, the number 2 filter more closely approximates the Pentax lens when both lenses are shot wide open.

It may not be entirely clear by looking at the above comparisons that the Pentax 85mm f/2.2 SMC Soft distorts the image in ways that the Nikkors deliberately avoid.  I should, however, be clear that changes in the aperture affects the "sharpness" of the subject focused on to a greater degree than it does out of focus areas around the edges.

Further, as previously noted, the depth of field of the Pentax lens does not appear to change with aperture changes.  This behaviour is dramatically different from the Nikon lenses where the depth of field changes as the aperture changes.  This difference in depth of field behaviour should be clear in the above comparison.

To illustrate what I mean when I say the Pentax lens distorts the scene, here are two photographs that show the difference between the Pentax 85mm f/2.2 SMC Soft and the Nikon Nikkor 85mm f/1.8 K pre-Ai with a Nikkor number 2 Soft filter mounted on the front.  The level of "softness" is similar, but the way the images are rendered are very different.

Nikon Nikkor 85mm K f/1.8 Soft Filter #2
Nikon Nikkor 85mm f/1.8 K pre-Ai at f/1.8

Pentax 85mm Soft f/2.2
Pentax 85mm f/2.2 SMC Soft at f/2.2

Wednesday, October 11, 2017

Out of Focus Rendition ~ a quick look at a few Nikkors and one Sony

Before the Strange Beasty Pentax 85mm f/2.2 Soft landed on my doorstep, I took a look at the out of focus rendition (OFFR) of various lenses that I have on hand.

Here is the incredibly boring but sufficient to the task scene.  It was taken with a Nikon Nikkor 85mm f/1.8 K pre-Ai shot wide open.

Nikon Nikkor 85mm f/1.8 K

Here is the comparison (follow the link and head to the files to select the largest, and then view it at 100 percent to clearly see what I will describe in just a moment).  All lenses were shot wide open.

Bokeh Studies

Organizing my comments by ranking these lenses from doughnut shaped OOFR to the smoothest -

  • Nikon Nikkor 50mm f/2 H pre-Ai
    [huge gap in OOFR]
  • Nikon Nikkor 50mm f/1.8 AiS
  • Nikon E-series 75-150mm f/3.5 AiS
  • Nikon Micro-Nikkor 55mm f/3.5 pre-Ai
  • Nikon Nikkor 135mm f/3.5 AiS
  • Nikon Nikkor 135mm f/2.8 pre-Ai
  • Sony 50mm f/1.8 SEL OSS
  • Nikon Nikkor 85mm f/1.8 K pre-Ai
  • Nikon Nikkor 105mm f/2.5 AiS
Looking at the old double gauss 50mm f/2 H OOFR I see what a Zeiss whitepaper on optical design described as over-corrected rendition.  Before I say the OOFR is "horrible" I would like to note that some people love the soap-bubble rendition.  Recently a manufacturer started selling lenses that deliberately give this effect, so who am I to judge?

What's interesting to me is that the more current implementation Nikon Nikkor 50mm f/1.8 AiS gives a much smoother OOFR (hence the previous note about a "huge gap in OOFR").  Looking at cross section diagrams of the two lenses (the f/2 vs the f/1.8) I see the classic double gauss implementation.  They look to be identical and I would've thought their performance to be more comparable, yet it's clearly not.

Further, if I'm correct in thinking about the cross section diagrams of the other lenses I compared here, all but one (the 75-150 E-series zoom) are in one form or another derivative double gauss designs.

If the goal is to find lenses that give smooth OOFR (that is to say, lenses that melt the OOFRs into creamy smoothness), then all but one (the Nikkor 50mm f/2 H) meet the criteria of "goodness".  The standout of the short, "standard" focal length lenses is the 50mm f/1.8 AiS.  It's OOFR is the best of any 50mm lens I've ever owned.  This one is a "keeper."

One surprise is the performance of the Micro-Nikkor 55mm f/3.5.  Yes, the aperture is somewhat small at f/3.5 so the depth of field is not razor thin when shot wide open.  Yet the OOFR is creamy smooth.  It's really quite interesting to see and might be very usable for shooting portraits where the nose and eyes are in focus.

Another surprise is the 75-150mm f/3.5 E-series zoom.  I read somewhere that this lens used to be a favorite of fashion photographers back in the day.  It was considered a "sleeper" lens, and I can see why.  This is a great lens for OOFR at _all_ apertures.  I don't understand it.  The aperture blades do not form a circle, yet the OOFR remains creamy and smooth all the way down thru f/11.  I'm not convinced Nikon designed the lens this way (it's cheap and not otherwise widely regarded), but the effect is clear.

The sharpest lens in the group when shot wide open is the 135mm f/3.5 Nikon Nikkor AiS.  Period.  There are not enough superlatives to explain just how brilliant the lens is.  The OOFR, however, is not quite as buttery-smooth as it's sister the f/2.8 135mm Q.

Stuck in the middle of all these Nikkors is a little Sony 50mm f/1.8 SEL OSS.  The link has disappeared, but there was a page out on the 'net that showed the Sony to be the equal of new Leica lenses.  Well, it's true (in my experience, at least).  The OFFR, too, is really quite outstanding.  For portraiture on APS-C Sony mirrorless this lens is a "keeper."

The 85mm f/1.8 K gives very nice OOFR and lightly "swirls" the background (ala Petzval).  I would've claimed it the winner in my OOFR comparison except for one lens.  And that lens is the 105mm f/2.5 AiS.  It is the smoothest-butteriest (how's that for making up  new words?) OOFR lens I currently own.  It's reputation appears to be well founded.

Prices on old manual focus lenses seem to be dropping.  Perhaps the market is finally saturated with lenses, new and old?  In any event, to stock up on optics to perform this comparison cost me very little.  The 50mm f/2 and f/1.8 lenses are commonly found for between 25Euro and 50Euro.  The 75-150mm E-Series, the 135mm f/3.5, and the 80-200mm f/4.5 lens (not compared here) were _all_ picked up in mint condition off eBay for around 40Euro each.  The 105mm f/2.5 AiS came as a trade for an 85mm f/1.8 H I had and cost me nothing.  The 135mm f/2.8 was very kindly given to me by a friend who picked up a Zeiss 135mm f/2.

In the end, this comparison is about finding many great lenses with wonderful OOFR, while, at the same time, costing next to nothing.

Monday, October 09, 2017

The Case of the Curious Optical Effect...

Something strange happened on the way to experiencing "softness" nirvana.  I've stumbled across an optical effect that I can't explain.

In optical designs I'm familiar with, "depth of field" increases as an aperture size is decreased (stopped down, as it were).  That's the commonly expected effect and is partly why lenses often come with aperture controls.

After looking at Jim Galli's soft focus large format images and thinking about how I might achieve similar effects in APS-C digital without returning to large format film, I stumbled across a small Pentax 85mm f/2.2 Soft in a Nikon F mount.  I'd never seen this lens in Nikon F, so I picked it up for not a huge sum of money.

Today I performed a quick comparison between the Pentax and my Nikon Nikkor 85mm f/1.8 K pre-Ai.  I was looking forward to shooting the Soft wide open and controlling the depth of field by stopping the aperture down a bit.

Looking at the comparisons and after the noting that the spherical aberrations decrease with aperture size (as expected), I noticed that the circle of confusion (said another way, the out of focus rendition) did not seem to change with the aperture.

What's going on here?  I have a mystery on my hands.  Perhaps one of my readers can help explain the optical effect?

Pentax 85mm f/2.2 Soft, Nikkor 85mm f/1.8 K Comparison

Here is a Nikkor "control" image where the 85mm f/1.8 K was shot wide open.

Nikon Nikkor 85mm f/1.8 K

Here is the Pentax 85mm f/2.2 Soft at f/2.2.  As you scroll through the images, look at the "size" of the out of focus bright area situated between the green plant in the center and the red flower just to the right.  You can also look at the "size" of the leaves in the background (upper left region).

Pentax 85mm Soft at f/2.2

Here is the Pentax 85mm f/2.2 Soft at f/2.8.

Pentax 85mm Soft at f/2.8

Here is the Pentax 85mm f/2.2 Soft at f/4.

Pentax 85mm Soft at f4

Here is the Pentax 85mm f/2.2 Soft at f/5.6.

Pentax 85mm Soft at f5.6

Thursday, September 28, 2017

Black and White ~ in portraiture

After learning about how to correctly emulate black and white film using a digital file, I've been wondering about all the different ways of applying this new (to me) knowledge.

One of my favorite subjects is people.  I've worked with creative costumers in Steampunk, Tribal Fusion, and Victorian Gothic communities in the US and Europe over the past 15 years and enjoy it.  While most people I work with are wanting something "unique" (meaning colors and textures and "interesting" lighting), I've had it in the back of my mind that I'd like to explore the late 1800's imaging esthetic.  A good example of the goal I would like, someday, to shoot for is the style of the work of Alex Timmerman.

Taking an image from a series of photos I did recently with Hua Costumes, I set about seeing how a black and white treatment might be approached.

Here is a processed color version of the image in question.

Vampire photoshoot ~ Hua Costumes

And here is the black and white conversion.

Hua Costumes ~ in B&W

By desaturating the color file, making sure the blacks are deep enough and that there is plenty of detail in the highlights, I simply moved the center of the "curve" up a little.   That is to say, I made the mid-tones lighter.

I could have combined this technique with the black and white filter selections to lighten or darken the skin (red/yellow to lighting, blue to darken).  In this case lightening the skin seemed to ruin the effect I was looking for and darkening the skin seemed to turn it to mud.

The reason I mention skin lightening/darkening is that this is what I was required to pay close attention to when I worked in a photo lab making black and white prints in Hollywood.  The images were used in the local parade of the stars tabloids and lightening the skin-tones hid many of the star's natural blemishes.  High-key skin tones were all the rage at the time and the approach seems to be well entrenched in image making, even today.

Which brings me to another point about converting color digital files to black and white for portraiture.  The skin tones do _not_ need to be high-key for an image to be effective.  In fact, I rather like having tone and texture in the skin.  It can give an image a sense of depth and dimension (roughly the saying the same thing, isn't it?).

Here is an example of deep skin tones.

This image was made during la Traversee de Paris Estivale 2016.  The gent was driving a very early deDion Bouton and he was well dressed for the part.  I shot this against a very bright sky using an old manual focus (therefore rather difficult to focus in rapidly changing situations) and extremely sharp Nikon Nikkor 80-200mm f/4.5 that was mounted on a Sony A6000 body.  The camera metered for the highlights (fortunately) and this kept the sky from "blowing out."

Once again using the technique of raising the mid-tones when converting a color digital file to black and white I was able to bring the darker areas of the scene up to what you see here.  The skin is obviously darker than in the images from the Hua Costumes vampiress shoot.  Yet to my way of looking at this image, the darker skin tones don't seem at all out of place.

In summary, it appears that deep, richblack and white portraiture that emulates the beauty of film can be achieved.  The more I work at this, the more I'm liking what I see.

Friday, September 01, 2017

Black and White ~ more image processing approaches

A recent revelation concerning the making of great digital black and white images has bowled me over.  The technique is where you desaturate an image and grab the center of the "curve" and raise it.  This is quick, straightforward and produces some very lovely results.

There are, of course, more than several ways of creating decent black and white images from digital color image files.  In this post I would like to share an alternative and still simple approach.

Capture One, Lightroom, Rawtherapee and many other image processing software applications provide tools that allow you to manipulate the color response in black and white, just as you might when decades ago you applied a colored filter to a lens while shooting black and white film.  Do you remember using a yellow filter to slightly darken the sky?  It's the same principle used here, but is processed after the image is taken, not while you're tripping the shutter.

Take, for example, the following image.

Audelange, Jura, France

Using Capture One I added selected  "Black and White" -> "Color Sensitivity" -> "Enable B&W."  This activates a number of color range selections.  The sliders for each selection allow you to lighten/darken colors individually.  I consider this my infinitely variable and all powerful  black and white "filter pack."

For the above image, using "curves" to raise the mid-tones made the building and the sky too bright.  So, instead, I darkened the blues to manage the sky.  This had the additional effect of making the side of the building reveal more detail.  Next, I moved the green slider around until it revealed the reflection of the building as well as the leaves in the trees and plants around the scene.

Using the "let's play around with this" approach to image processing allowed me to lighten the areas I wanted and to selectively darken certain elements of the scene.  In this way I was able to selectively raise certain mid-tone colors.  The overall effect is subtle, and effective.

You might not be able to fully predict how the sliders will behave, so it's good to play around with the sliders in the "filter pack" until you find something you really like.

I enjoy looking at this image as it reminds me of the sensation of warmth of the late afternoon light I felt on that particular day in the village of Dole in the Jura region of France.

Wednesday, August 23, 2017

Black and White photography ~ comparing digital to film

I've been looking at many details and have been exploring several avenues of thought since my last post about discovering how to make digital images look like film.

In this entry I would like to take a brief look at images I made using both imaging mediums.

I kept some of my earlier black and white film negatives and brought them with me.  Selecting a couple train images I set about digitizing them.  Using a macro lens I shot sections of 4x5 inch negatives, stitched them together, and simply moved the top and bottom of the curve to the white and black points in the stitched file.  This gave me large files (on average 8000 x 6000) where the film grain is clearly visible and the full range of luminosity of the original negative was expressed.  I made no attempt to modify the shape of the curve (as you might with a digital file where some people might want to apply an "S" shaped curve, or something similar).

For train images shot as digital, I applied the technique described by The Online Photographer.  That is to say, I snugged up the black end of the curve, ensured there was a lot of detail in the highlights, and raised the center of the curve to bring up the mid-tones.  For both the digitized film and the digitally captured images I applied a platinum/palladium tone that I particularly like.

Here is a film-based image.  As you can see, it's from a 4x5 inch Polaroid Type-55 P/N negative.  I shot it at ISO 25 (the film side was always slower than the print side).  The Polaroid output was always more contrasty than Kodak TMax100 negatives, too.  I discovered Type-55 P/N very late in the film era and rather wish Polaroid was still around.  I'd probably have to have a 4x5 camera and a few lenses just to shoot that wonderful material.

Given the lighting situation in the old Brooklyn Roundhouse in Portland, Oregon it's surprising that the Polaroid negative shows detail in the highlights and shadows.  The shadows were very deep and the highlights could be very bright, even on overcast days.  I find this remarkable as I remember carping about all manner of silliness and was seldom happy with my results.  Yet, take a look at this.  I must have mellowed a bit over the years. I now think it's a beautiful image.

SP4449 ~ old Brooklyn Roundhouso

Here is a digitally captured image.  As you can see, I used an ultra-wide angle lens and captured the scene under remarkably similar conditions to the Polaroid Type-55 image above.  It was an overcast day in Longueville, France and the steam locomotive was pointed head-first out the doors.

The original digital image was actually shot as part of a three image HDR stack.  I used Rawtherapee to process the original Canon CR2 raw file.  In fact, I chose to work only on the -2EV image to see what I could do to keep sufficient detail in the highlights while raising the shadows.

As an aside, and if you'll recall, the Canon 5D MkII took a beating in the public forums for it's "banding issues."  Yet, using a file that was 2 stops _under-exposed_ and leaning heavily on the "shadows" slider shows no "banding issues" of any kind.  Additionally, the original 12-24mm Sigma EX HSM lens seldom received much love from the community of online photo-forum commenters.  To my eyes the edge to edge resolution and flair control seem excellent.

AJECTA ~ Longueville, France

The "character" of the two images, to me, is remarkably similar.  If I hadn't talked about each image before reaching these comments (and ignoring the Polaroid Type-55 edge), would you have been able to tell which imaging medium produced which image?

Monday, July 24, 2017

Black and White photography in the Digital Age

Back in the day (yes, I'm that old, but I can assure you I only walked up hill to school in one direction) all I shot was black and white.  Color was too difficult to control and the costs too high.  After years of working in black and white my "eye" became conditioned to a certain "look".  The mid-tones of a nice gelatin print could be a big beautiful sea of wonderful grays.

Time marches on, as they say and I've been less than happy with my digital images when I've tried to convert them to black and white.  I wasn't sure what the problem was, but every conversion and every filter and every film type I applied left me less than satisfied.  Try as I might, I couldn't figure out what the problem was.

So... I shot digital color and found I love it.

However, recently, Mike Johnson on his The Online Photographer blog posted two articles.  The first is titled "How to Cure the Digital B&W Nasties."  Well, there we have it.  The complete problem statement of what I felt I've been encountering since Day One of my transition to digital.  The second blog entry added a few details on how to make a decent B&W image using current tools.  It's titled "Look at Tone as Light."

Moving from "digital nasties" to a near perfect match for old film is much much easier than I'd ever imagined.  The key, for me, was in reading how a photographer who's work I greatly admire dealt with a student's image.

greg brophy: "... I once asked Carl [Weese] to help me with a B&W photo and he basically lifted the midtones."

There you have it.  The Answer.

Certainly there are many things a photographer can do in converting a color digital image into a decent black and white photo.  There are color channels you can manipulate.  There are "S shaped tone curves" you can apply.  And, yes, there are pre-canned film presets you can select.  I've tried them all and was not at all happy with any of them.

After having reconsidered the topic thanks to The Online Photographer, I think I've finally made peace with digital cameras and black and white imaging.  And I'm finding I'm enjoying working in black and white again.

Here is a Flickr album that illustrates my current understanding of the conversion technique.

Audelange, Jura, France