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09-28-2012, 03:50 AM   #16
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QuoteOriginally posted by elliott Quote
I think it is a lot like distortion in the audio world, it doesn't take much to get rid of 99% of distortion in an audio system, but that last 1% that the audiophiles crave is expensive.

The old SMC coatings are very good when comparing it to single coated or uncoated glass, any improvement over SMC is just small steps, not a huge leap that is easily noticeable.

The biggest thing about the pre-digital glass is the coating on the rear element, it wasn't necessary to have good coatings on the rear element with film. The digital sensor is reflective, film is not, so on digital you can get ghosting in certain conditions that would not have been a problem on film. I've found this to be an extremely rare occurrence and I have to almost force it to happen.
I had deduced the digital sensor was much more reflective than film because of an effect I found with an AutoTak35/3.5 compared with SMC Tak 35/3.5. The ATak gave low contrast and slightly fogged images, whereas the SMC did not. The only differnece in the glass was the coating. But the rear end of the lens had a small element and in the AutoTak an anodised slightly shiny surface andthe SMC Tak ad matt black paint.

Result, reflection from the sensor was reflected byt he AutoTak back to the sensor, spoiling the image. The SMC Tak did not reflect and produced better images, just like all the other SuperTak and SMC Tak lenses I have at the wider angles. The tele lenses are different - they have larger rear elements and so do not present smooth rear ends towads the sensor. But they need light absorbing tubes from the mount forward wuite some way because the rear element is quite far in.

09-28-2012, 04:18 AM   #17
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QuoteOriginally posted by tim60 Quote
I had deduced the digital sensor was much more reflective than film because of an effect I found with an AutoTak35/3.5 compared with SMC Tak 35/3.5. The ATak gave low contrast and slightly fogged images, whereas the SMC did not. The only differnece in the glass was the coating. But the rear end of the lens had a small element and in the AutoTak an anodised slightly shiny surface andthe SMC Tak ad matt black paint.

Result, reflection from the sensor was reflected byt he AutoTak back to the sensor, spoiling the image. The SMC Tak did not reflect and produced better images, just like all the other SuperTak and SMC Tak lenses I have at the wider angles. The tele lenses are different - they have larger rear elements and so do not present smooth rear ends towads the sensor. But they need light absorbing tubes from the mount forward wuite some way because the rear element is quite far in.
If the issue is the shinny ring on the lens, this will wide open produce a low contrast sho, and stopped down yo will see an annular ring. I had an XR-Rikenon like this, and I painted the lens retaining ring black to solve the problem. Others have had the same issue with 645-Kadaptors

You should also note that general low contrast lenses can be greatly assisted with a hood. Use one from a lens that is longer, I use one from a 105mm on my 50, and the one from my 50 on my 35
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