Fitting a monster Pentacon 500mm lens to the Sony NEX 5R

Fitting a monster Pentacon 500mm lens to the Sony NEX 5R mirrorless camera. Look at the picture below; is this a Sony NEX camera fitted with a long focus Pentacon lens, or a huge 500mm lens with a digital sensor hanging off the end of it? From whichever way we look at it, it is an intriguing combination. On my recent trip to Europe I wanted to see what photographic images BIG Pentacon daddy and Sony baby could come up with through their unlikely union.

By the way, back in the late 1970s I used this huge Pentacon 500mm lens with my Pentacon Six medium format camera . (For those who don't know, Pentacon was a large East German photographic equipment manufacturer with an interesting history. Their best known brand was the Praktica.) As you would expect, for the last couple of decades this lens lay dormant in the depth of my closet. With the advent of exchangeable lens mirrorless cameras it is now time for a resurrection.

Since the lens was originally designed for the Pentacon Six, which has a large breech-lock lens mount, a way had to be found to attach it to the Sony NEX. Luckily, Pentacon made an adapter for their M42 screw mount Praktica cameras, and I happened to have one of these now rare treasures. I also bought a Kipon M42-to-NEX adapter. A wooden tripod from the same era (also made by Pentacon) completed the outfit.
(Note: the Sony NEX 5R was reviewed in my previous post).

I can't say that lugging around this monster lens and the tripod was much fun - the Sony being an insignificant addition as far as the weight was concerned -, but curiosity took the upper hand in me.
When I set-up, I first took a photograph with a 35mm Flektogon lens to provide a basis for field-of-view comparison. (This lens will be evaluated in my next post.) On the Sony NEX 5R the 35mm focal length roughly translates to a standard lens in 35mm film format. The 500mm Pentacon acts like a massive 750mm telefocus lens!

Below is the first image I took with the 35mm Flektogon to set the scene. Here it is reduced to one-twelfth of its original size. I must say that this tiny resemblance of an otherwise splendid view looks dreary on the computer monitor. I usually take photos like this onto slide film and they look great when projected onto a screen more than a meter wide.

35mm Flektogon f/11 1/400 sec. ISO 200

Perhaps the next image presents a better view. This is a detail of the same picture shrunk to 'only' one-third of the original. It will hardly be noticeable here, but the focus was set on some foliage nearby and the aperture closed down to bring near and far objects within the depth of field. Surprising at first, but otherwise quite understandable is the fact that with high magnification - as we usually scrutinise digital images nowadays - objects that are still well within the traditionally accepted depth of field, but not in exact focus do look distinctly - and perhaps annoyingly - unsharp. This is the case with the Royal Palace in the distance.
I guess the solution is not to get too hung-up on sharpness. After all, famous photographs of great masters are remembered and admired today not for their sharpness, but other qualities.

One more note on image quality: I checked these pictures on a few different computer monitors and there was a significant variation in how they looked. The output device is only one of many factors contributing to the perception of sharpness, colour, etc. in a photograph, but I think it is one of the most influential. Unfortunately, that also makes the performance evaluation of a lens - when that evaluation is based on photographs posted on the internet - rather uncertain. (Does this sound like a disclaimer ...?)

Ok, let's get back to the 500mm Pentacon lens. The next photograph was shot with this lens from the same location as the previous one. Here it is reduced to 12.5%. The reduction might have taken some of the quality out of the image. By the way, I have to confess I am behind the times with image editing software; I run Photoshop version 6 on my computer, which is more than a decade old. I would imagine modern software uses better algorithms, but than again, some things don't change much.

500mm Pentacon f/16 1/250 sec. ISO 200

Here is a crop from the full-size image.

Below is another detail from the same image. This area is out of focus. With a lens as long as this, depth-of-field is shallow and does not extend from the church tower to this stone wall. (The focus was set on the clock.)

Here is a challenge; find this detail on the first picture above. (If you can't, try the second one.)

Turning my camera to another direction, but still remaining in the same spot, I found this photographic subject:

35mm Flektogon f/8-11 1/500 sec. ISO 200

Again, the image reduced to this size crams too much detail into a small space, but I wanted to give a wide view of the scene from which I pick out a smaller area with the telefocus lens. But before we move onto that, here is a crop from the middle part of the unreduced image.

The 500mm Pentacon lens brings the distant ship and surrounds much closer. So close, that one can easily read the name of the ship; Rousse Prestige.

500mm Pentacon f/16 1/400 sec. ISO 200

Below are full-size crops from the unreduced image.
How good is this lens on the Sony NEX?
I think it is ok, but it doesn't take my breath away. What do you think?

Somehow it seems to me that the left side is softer, more blurry, than the right side.
It was hard to keep the lens still on the tripod. It had to be sheltered from the breeze and I used the self timer to allow any movement to die down after I pressed the shutter release button. While this wooden tripod was a good, steady one, it was not quite heavy enough for this massive lens. Had I mounted the lens on a more substantial tripod, I think the results would have been slightly better.

I think the biggest problem with this lens is the colour fringing which is well visible here on this 200% enlargement.

According to tests made by others, the Sony NEX sensor does not exhibit much noise at all. However, if the noise is made up of different coloured dots rather than a uniform colour, then it is much more noticeable. I think this is what we see here on the wall, for instance, and I put this down to the lens, rather than the camera. (JPEG compression may have made it even worse.)

Some more photos taken from the same location...
This couple was standing near the left suspender cable of the white bridge seen above where the cable hits the ground.

500mm Pentacon f/11 1/100 sec. ISO 200

I am not good at judging distances so I will not offer an estimate. (Unfortunately, I forgot to record the distance setting on the lens and, being it a manual focus lens, this is not included in the picture info stored by the camera.) However, you can get an idea of the distance, if you refer to the earlier picture.

Long-distance portrait of a man ...

... and a woman. Both are crops from the full-size image.

These pictures will not win a prize on a photographic competition, but if these people were celebrities and I was a paparazzo perhaps they would make it into some women's magazines.

Judging from their body language these two were arguing about something, but boy! they are on common ground down below. :-)

This next picture was taken across the river, just like the one with the ship. (This part of the river bank is to the left of the bridge.) This image was not edited in any way, except to reduce its size to fit the screen. I loaded it up in Sony's RAW Image Data Converter ver. 4., converted it to TIFF format, opened the file in Photoshop, shrunk it down to 12.5% and saved it as a JPEG.

500mm Pentacon f/16 1/200 sec. ISO 200

The detail below demonstrates that with the right equipment you can take a recognisable image of a friend from almost half a kilometre away. (Now I'm not guessing; I looked up the width of the river - 350m - and added the extra distance on the land - cc. 100m.)

Interestingly, the footpath and the yellow building behind the people were almost entirely inundated by the recent floods that swept through the city. (Unfortunately, I moved on just ten days before this happened and, thus, missed out on 'flood stricken city' pictures.)

What seems to be a consistent feature of the images I took with the Pentacon 500mm lens is some haziness (even though a lens hood was used), and that image data on the histogram only occupies a somewhat condensed range (e.g. 11..216, 20..249). Bringing the levels down to these values in Photoshop clears up the image, but also results in too much contrast. Obviously, one could get a lot more sophisticated and employ some advanced image editing wizardry and probably end up with quite a decent image, but on this occasion I stayed with the very basics. The idea was to show what the pictures look like pretty much as they come out of the camera.

Finally a photo of our good old and faithful satellite, the moon. Unfortunately, the atmospheric conditions were not ideal; it rained throughout the day and although cleared up by night fall, there remained some vapour in the air. This image is 50% of the original.

500mm Pentacon f/8 1/25 sec. ISO 400

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  1. Thanks for sharing!

  2. Many Thanks for sharing your valuable pictures and reviews

  3. To appreciate this lens one should remember that the ap-c sensor of this Nex 5R fits more than eight times into the size of the film negative this lens was designed for.