So, I tested for the first time the rotating Vertex adapter, with the Pentax 6x7 Takumar 150 mm f 2.8 lens and Canon EOS R, doing the 4 images thing... stitching them together... and well... it was so-so.


Minimal depth of sharpness

The depths of sharpness with the Pentax 6x7 Takumar 150 mm f 2.8 is extremely shallow. I also made several mistakes, like too long shutter speed (1/6 sec)., and the fine details were a little outside the sharp focus (eyes). The Pentax 67 SMC 150/2.8 is when used wide open at minimum distance softer than normal. Either i set the focus not properly or Sal moved 1-2 cm backwards, as his eyes where just right outside the sharp focus.

I also had to deal with chromatic aberration quite a lot, visible in the finer details when looking at 100% in the 75 MP file. Which by the way is not visible in the photo above, because it is so much smaller compared to the 75 MP original and I applied mild sharpening.

I also made errors on the original file with the Topaz Sharpening AI, noticing too creating ugly artifacts (in a different photo version, not shown here).

Ah. Oh. Hm.... Grrr.

Still LOTS to learn. And lots to practice.


The process

Below you see how the principle of the Vertex adapter works, with Pentax 6x7 Medium format lenses, and the Canon EOS R camera being tilted around for every frame by 90 degrees. Then you stitch all four images together, and the result is as if you took the image with a digital 46x46mm sensor.



However: Sal did keep still !

Stitching was actually not a problem at all. It went flawless.

I will definitely make more experiments, with various portrait settings, just to see what works, and what doesn't. And how the close up quality is, versus, the overall image quality (which is usually better when a photo is seen as a whole).

Another tricky thing is to judge the frame - because... well, you only see 1 of 4 frames (at a time), never the whole image, nor the expression of the face "like in a photo" (as you would so in a real 6x6 or 6x7 camera). I guess, it is a little bit like working with a 4x5" largeformat camera. Once you set in the film, you can't see the person in the frame though the camera.

With analog largeformat 4x5" photography - you really have to stand still !


Mixed feelings. But fun !

I am not used to take portrait images like this - and it all feels very clumsy to say the leas. BUT interesting, too !! Kind of fun as well. You have to instruct your model, and everything is quite a bit slower than normal. Which can be made into an advantage, because you are really working together.

Poor Sal, He was still relatively newly awakened *grin* I put his face on the table, in order to make it easier for him to keep still. But we will test other settings as well, and see what works, and the things that what need to be closer paid attention to.


It was just a test shot.

Just a first glimpse of how the rotating Vertex adapter and stitching works on a person... Well, so this is now a real medium format made portrait (46x46 mm).

Nevertheless - it is a start ! And it really is both challenging as it is really fun ! So, different from the normal quick paint and shoot. Or 'paintbrush' photography, bam-bam-bam.

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