Wednesday, January 17, 2018

Lens Comparison ~ Nikon Nikkor 135mm, 300mm + Komura 2X against Tamron 150-600mm f/4.5-6.3

Something that I've wondered out for many years is just how good or bad 2x teleconverters can be from back in the day.

Recently I stumbled on a Komura Telemore 2x teleconverter.  It was relatively cheap and I was interested to see how it might perform.

Comparison Setup -
  • Sony NEX-5T, 100ISO, 2 second timer, "A" aperture preferred mode
  • Nikon Nikkor
    • 300mm f/4.5 pre-Ai - two passes, one with and another without Komura Telemore 2x converter
    • 135mm f/2.8 Ai + Komura Telemore 2x converter
  • Tamron 150-600mm f/4.5-6.3 version 1 on Sony AF adapter
  • Scene shot through double pane glass window (it was too damned cold to open the window for a clear shot)
Here is the scene at 300mm -

Nikkor 300mm f/4.5

Here is the scene at 600mm - 

Nikkor 300mm f8 Komura 2x

Comparison Results -

[If you click on the image it'll take you to the Flickr hosting site. Once there you and 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 image at 100 percent.]

Nikkor 300mm 135mm Doubleur Tamron "Bigron" Comparisonb

Observations -

Looking at the Nikon Nikkor 300mm f/4.5 pre-Ai against the Tamron 150-600mm f/4.5-6.3 at 300mm shows not much difference between the two lenses in the center of the field.  As you can see, the single coated Nikkor is slightly less contrasty than the modern Tamron.  This can be easily corrected in processing by applying a gentle increase in contrast.  The edges of the frame show something interesting.  The Nikkor remains sharp where the Tamron gets slightly softer as the edge of the field is approached.

The Nikon Nikkor 135mm f/2.8 Ai mounted on the Komura Telemore 2x teleconverter shows that the Komura degrades performance rather rapidly.  At no aperture does the teleconverted Nikkor come close to wither the un-teleconverted 300mm Nikkor nor the Tamron.  Obvious decreases in contrast and resolution can be seen.

The same things can be said about the Nikkor 300mm, Komura Telemore combination.  Contrast is decreased and the resolution never really matches the modern Tamron "Bigron" zoom.  I can increase the contrast in processing, but there is no way to gain back resolution after the shutter has been tripped.

I was hoping to find a light(er) weight manual focus lens combination that I could use at the racetrack to photograph old cars and MotoGP motorcycles.  I won't be able to meet that goal with the Komura and Nikkor lenses.  For now I'll need to stay with the Tamron super zoom, which, it seems, performs admirably well.

Saturday, January 06, 2018

Is Photography Really Dead???

PetaPixel published an article that asks if photography is really dead.

I have to admit, the author makes more than a few decent points.

"...But what died, exactly? The techie crowd had become bored with these particular machines, moving on to newer, shinier gadgets, and young people, like most young people, just wanted to hook up. Nothing wrong with either, and certainly nothing new. The dedicated photographers who had been working quietly and being ignored likewise continued in this fashion, and will keep doing so even while everyone else is using brain implants to beam live VR experiences featuring their cats..."

It's the being ignored part that can be a little difficult.  Or more properly, it's the being unknown and unfindable part that working in isolation can bring.  Dedicated artists like to share their work and in the narcissistic world of social media self promotion it's very difficult to carry on any kind of conversation about the art and craft of imaging.

Here I sit in one of the most photographed cities in the world and yet I can count on fewer than two digits the number of dedicated photographers who live here as a friend or colleague.  All of my photographer friends live either in New York or out on the west coast of the USA.  Perhaps it's telling that many among these dedicated artists continue to pursue their vision using old tools, techniques, and processes.

I miss being able to sit around a table stacked with beers and "talking shop" and sharing the results of our latest efforts.  Doing so remotely, electronically, just doesn't carry the same impact as meeting someone face to face.  I learned so much from our casual conversations.

I learned about optics and the fact that lens coatings exist that make the glass disappear.  One of the gents I talked with worked in an optical company where the process and results were demonstrated.

I learned a lot about process.  Two other gents helped me understand the proper tools and techniques of hand-coating platinum-palladium solutions for making contact prints that can last unchanged for over 500 years.

I learned a lot about how to work with models.  Several gents continue to create gorgeous images of models.  They work both in the studio and in the open air.  Dealing with people takes time, intelligence, and the ability to convey emotions in sometimes subtle ways.

While there are so many aspects to photography that I will never fully grasp, simply talking with others helped to fill in the "blank spaces".

Many are the days when I consider "pulling the plug" on social media participation.  Though I know in doing so I could completely turn out the image sharing, conversation starter, art as a movement welcoming and participation light.

Nikon Nikkor + Lens TurboII + Sony A5000

Thursday, January 04, 2018

Comparison ~ Nikon Nikkor 300mm, 135mm, 105mm + Lens Turbo II

Continuing to troll the 'net for 50Euro or less highest quality lenses yielded up a Few More Fun Things.

Last year I sold a mint 300mm Nikon Nikkor f/4.5 pre-Ai lens.  Of course I started to regret the sale.  It was a really nice, sharp optic.  So when another came available at half the cost of the first 300mm, I jumped at it.

What I now have is an excellent condition 300mm lens that dates even earlier than my first example.  The focusing collar is smooth and accurate (nearly Super-Takumar-like in this respect, which is a surprise for such an old Nikkor).  The exterior condition is excellent.  But the front element has a few cleaning marks.  They are very light, very fine marks, but, neurotic as I am about such things, I know they are there.  I may learn to live with it.

The setup -
  • Sony A6000, 100ISO, AWR converted in Sony's software 
  • Big Beefy Manfrotto tripod 
  • Nikon Nikkor 
    • 300mm f/4.5 pre-Ai (c.1971)
    • 135mm f/3.5 Ai
    • 105mm f/2.5 Ai
    • all mounted on a Lens Turbo II focal length reducer
  • One pass where 300mm f/4.5 images were processed
    • Gimp -> FX Foundry Luminosity Sharpen
    • Gimp -> Curves (subtle adjustments to tonal range)
The results -

Here is the scene setup -

Scene Setup Nikkor 300mm, 135mm, 105mm comparison

Here are the results.

[If you click on the image it'll take you to the Flickr hosting site. Once there you and 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 image at 100 percent.]

Nikon Nikkor 300mm, 135mm, 105mm Comparison

My observations -

The Nikon Nikkor 300mm f/4.5 pre-Ai stands up rather well against the wickedly sharp 135mm f/3.5 Ai.

Wide open the 300mm shows softness that typically comes from spherical aberrations.  You can see the effect around the large lettering.  One stop down and the 300mm seems to match the shorter focal length lenses across the field.

The 105mm f/2.5 Ai suffers at f/4 and a little at f/5.6 in the corners.  I think it is an effect of field curvature, particularly when the lens is used with the Lens Turbo II focal reducer.  I've seen similar things when making these kinds of 2D flat sheets of newsprint comparisons between various lenses.  I've specifically seen the effect with the 85mm "K" pre-Ai Nikkor, Lens Turbo II combination.

My comparisons are always made using un-altered, straight off the sensor images.  I convert AWR files using Sony's conversion software and I leave that software with it's default settings.  I never add nor subtract, for instance, "sharpness" nor contrast.

With this comparison I added a line where I took the 300mm Nikkor images and passed them through the Gimp and two functions.  Specifically, I passed the images through FX Foundry's Luminosity Sharpen and used "Curves" to try and match the tonal range of the 135mm f/3.5 images.

Luminosity Sharpen is a very subtle sharpener.  I think it's better than many "smart" sharpen algorithms in that Luminosity lightly touches the light/dark transitions and leaves the smooth areas alone.  Images don't typically look hard sharpened when I use this function.

What I find is that lightly processing the 300mm f/4.5 wide open image yields results that appear to match the wickedly sharp 135mm straight off the sensor results.  Carefully using "Curves" I was even able to reduce the effects of spherical aberration (look at the large lettering).  At f/5.6 and f/8 the 300mm lightly processed image results appear to as "sharp" as anything in this comparison.

The "sharpening" aspect of the processing is to carefully increase transitional zone contrast.  The human eye perceives this as "sharpness".   This means that just about any file made with a well designed and constructed optical system can be carefully "sharpened" to the point that the results appear sharper than the off the sensor originals.

While there is nothing new in recognizing the effects of "smart" sharpen functions, what I find interesting and promising is that in using these controls, I might be able to use this Nikon Nikkor 300mm f/4.5 pre-Ai for photographing motorsports and birds and exceed the results I used to obtain from my old Canon 7D, 100-400mm zoom kit.