MS Optics - Hexar AF 35/2 lens conversions

Hi all, does anyone have experience with the Hexar AF lens conversions by MS Optics? I had a dead Hexar so I decided to send it off and have the lens converted, I heard nothing but great things about these. Got the lens back but it has a lot of distortion on the sides (sometimes not though, depending of the busyness or not busyness of the content), it also seems to not really be in focus sharply anywhere. It seems to look in focus on the surface, but with close examination it's soft all over. Maybe it is just soft... For sure not sharp like my collapsible Summicron. Sometimes it looks ok, sometimes not? Also it tends to blow out highlights easily. So if anyone has insight on these lenses I'd love to know. I look at sample images on the web and they all look great... But, there is always post processing. Thanks in advance.

Several things:

Overly dense highlights are not an optical fault - they are usually from excessive processing time and/ or drastic overexposure. A modern multicoated optic will be considerably more contrasty than a mid-1950's single coated one & may need adjustments in processing times to compensate.

The Hexar AF's focus system was (I vaguely recall) designed to allow a degree of focus shift to occur in the lens design for optimal performance at bigger apertures, compensated for by the AF system, or something like that. Obviously, the OEM MF variant probably had a slightly different optimisation. Removing the elements & rebarrelling them will therefore not necessarily give the same performance as the original setup did. Again, the edge distortion may relate to this.

Have you compared it with an unconverted Hexar AF via top quality optical prints or high end scans?

Exactly correct; the Hexar AF compensated for focus shift. AFAIK the actual individual elements are not removed just the front and rear set; one or both may be slightly forward or back in relation to each other. I would attempt (if handy) to slightly reset the torque on those groups and re-test with a known accurate RF.

Hi, so that is interesting that if there is a focus shift to compensate for bigger apertures which has a correlation to the AF. So, if there is no AF what happens with that focus shift? So yes, I guess removing the elements would not give the same performance since the lens is designed for it's native setting with the AF. These are a fairly popular conversion though, with good reviews. I do have an intact Hexar AF which is stellar, it's very easy to see the difference between the original and the conversion, they don't even compare. I did contact Dirk at Japan Exposures and he said the focusing issue could addressed by adjusting the cam. They just take out the elements and put it in a helicoid. But, the tech slip said they were out of stock on 35mm helicoids so they used a 28mm? But, don't know what the effect would be and I figure they know what they are doing. BUT, he did say that if I had used a previously untested lens, then we wouldn't know if in fact that lens had problems to start with! I would also say it's not contrasty, hard to explain, but all images have to be adjusted in post. I'll post some images.

Can I send the lens to someone to reset the elements? I would think that if doing these conversions that would be accounted for.

Actual Hexar AF image

Meow7 said:

Hi all, does anyone have experience with the Hexar AF lens conversions by MS Optics? I had a dead Hexar so I decided to send it off and have the lens converted, I heard nothing but great things about these. Got the lens back but it has a lot of distortion on the sides (sometimes not though, depending of the busyness or not busyness of the content), it also seems to not really be in focus sharply anywhere. It seems to look in focus on the surface, but with close examination it's soft all over. Maybe it is just soft... For sure not sharp like my collapsible Summicron. Sometimes it looks ok, sometimes not? Also it tends to blow out highlights easily. So if anyone has insight on these lenses I'd love to know. I look at sample images on the web and they all look great... But, there is always post processing. Thanks in advance.

Click to expand...

Mine is astoundingly good. I just wish it had more manual controls across a wider range and could do longer exposures. Not much good in low light.

I love my Hexar, I just kind of feel like I'm cheating when I use it. I do wish the manual controls were a bit more user friendly.