Interesting article: "36 Megapixels vs 6×7 Velvia" and 4 x 5

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Originally Posted by Ken Lee

The mirror can be locked up, no ?

See http://www.mamiyaleaf.com/assets/fil...Z67_Pro_v4.pdf page 29:

With the RZ 67, it is possible to lock the mirror in the up position beforehand, and at the desired instant release the shutter without the usual accompanying mirror movement. Referred to as “mirror-up operation,” this technique is extremely valuable when desiring to eliminate even the slightest mirror shock...

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I only have a lowly RB-67 Pro-S, but with the double cable release, I push down halfway to release the mirror, wait a second and push down the rest of the way to take the shot. Piece of pie. Easy as cake. Even I can do it.

Having owned and used both a Pentax 67 system and a Mamiya 7 system I agree with Sal. Pentax 67 lenses don't come close to Mamiya 7 lenses in terms of resolution. My own resolution tests consistently gave between 25%-40% higher resolution with Mamiya 7 lenses than Pentax 6X7 when comparing the same film.

Sandy

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Originally Posted by koh303

Mirror shake on the RZ needs to be considered more then glass quality. Modern RZ lenses, have usually tested better resolution then 7 lenses, last time i checked.

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I found the Mamiya 7 65mm lens to be superior to the RZ 65mm lens with the floating elements. This was not the result of any rigorous testing, just looking at the results. Those were the only two lenses I had with a focal length overlap. However with the 150mm 7 lens I rarely get anything I want perfectly in focus. So there the longer RZ lenses gave me better results.

Tim Parkin and others have tested the Mamiya 7 lens to be some of the best lens ever, for any format. On the GetDPI, someone is challenging Tim for a "shootout" with the Sony A7R with image stacking (e.g. up to 60 images to extract the cleanest shadow details) vs. 8x10. Should be interesting.

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Originally Posted by richardman

Tim Parkin and others have tested the Mamiya 7 lens to be some of the best lens ever, for any format. On the GetDPI, someone is challenging Tim for a "shootout" with the Sony A7R with image stacking (e.g. up to 60 images to extract the cleanest shadow details) vs. 8x10. Should be interesting.

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The major flaw that I foresee in this 'comparison' is the time involved in creating that (60?) shot layered photograph... In most cases, I'd assume that the exposure time of the 8x10 shot will be long over before the digital fellow is finished with 1/2 the necessary shots for that layer cake...

There's always going to be those that want to argue ;)

It would interesting if the testers could assign points for different factors like price, scanner quality, user learning curve, etc. to make more useful practical comparisons. After all if you throw enough time, money, expertise at a test I am sure a multi-stacked and stitched digital could eventually trump 8x10 with a high end scan if you just kept adding frames until it won.

But I'm more interested in comparing single shots from more modest equipment and workflows.

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Originally Posted by Bernice Loui

moiré pattern in the digital test images. What has been done in the digital image processing to result in those images that give the appearance of being higher resolution.

They look digital on the Mac Book Pro display via the web.


Bernice

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Not sure what you mean - there is definitely moire in the test images, exacerbated because it was a D800E.

Tim

The film and digital images were fairly extensively post processed. Deconvolution sharpening etc.. Only fair to both platforms to get them optimally sharpened etc..

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Originally Posted by Ken Lee

My only reservation/observation is that the Mamiya 7 used in the test is a rangefinder camera: precise focus is dependent on calibration of the rangefinder mechanism.

I don't know if the lenses for Mamiya RB67 are basically "diffraction limited" IE optimal as are the Mamiya 7 lenses but if they are, the resulting images could be even better than those obtainable from a Mamiya 7. A Pentax 67 might do better also for the same reason.

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We bracketed the Mamiya 7 images but we were confident we would be OK as the depth of field covered most of the table at f/8 (about 20cm if I remember correctly). We put a video camera to the Mamiya 7 rangefinder and zoomed in (live view!) and the frame we used from this was spot on

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Originally Posted by richardman

On the GetDPI, someone is challenging Tim for a "shootout" with the Sony A7R with image stacking (e.g. up to 60 images to extract the cleanest shadow details) vs. 8x10. Should be interesting.

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Yes that should be interesting. We're going to do a single shot test (otherwise I'd just bracket 8x10 images!). He's more interested in signal to noise ratio in the shadows..