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01-07-2009, 06:19 PM   #1
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Posts: 71
Hasselblad CFE 40mm on K20D, pointless?

Found a cheap adapter on eBay. I'm not sure if anyone has tried this, but do you think it is worth the while tinkering with it or a complete waste of time?

01-07-2009, 06:41 PM   #2
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Tinkering is almost always worth doing (as long as risk of damage is very said cost is also low). Presuming you already have the Hassy lens?

A word of interest. It is my understanding that medium format lenses actually have lower resolving power than 35mm/digi lenses. But due to the larger format the actual result ends up better--with Hasselblad's 6x6 image you need only 1/4 the magnification to achieve the same print size, so even at 1/4 the resolving power you come out equal. For example, it is fairly common for quality lenses for digital SLR's to resolve 60 lines per mm in a resolution test. MF lenses more commonly resolve more like 30 lines per mm with 60 being above and beyond the norms. (don't hold me to these exact figures as I'm working from memory here and I don't know the precise resolving power of your specific lens). Because the 6x6 Hasselblad frame is more than 4x the size of the K20D sensor, your "crop factor" costs you the perceived resolution, ie the K20D crop factor zeroes in on such a small segment of the image circle thus the format advantage inherent in MF lenses is lost.

Now that's not to say that your lens won't produce great images on the probably will. And this is certainly not the last word as some of the more technically inclined on this forum can certainly provide more scientifically sound analysis than I just did. Also note that in the Lens Database you can find a succesful use of a Pentax MF lens on the K20D. As I recall, it's under the M*400/4 listing for 6x7.

Have fun and tinker away!
01-07-2009, 06:52 PM   #3
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Posts: 71
Original Poster
Thank you for the detailed reply, that's exactly the kind of information I was looking for!

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