digital 21 megas shot versus 6x9 cm slide film scanned

[sanking]

A couple of comments .

First, Pentax 67 optics don't come close to Mamiya 711. I once owned both systems at the same time and in my comparisons, which involved both real life photography and tests with targets, Mamiay 7II lenses gave between 25-45% more detail than Pentax 67 lenses.

Second, tonality is not uniquely a quality of real estate (area) with film. It also depends on grain and film contrast. Tonal transition values are much better with fine grain B&W films than with medium speed and high speed films. In general if you compare 4X5 and MF film of the same type and speed the tonal transitions will be better with 4X5 at the same magnification. But if you make the comparison between a high speed (ASA 400) film in 4X5 with a medium speed film (ASA 100) in MF results should be quite similar.

Sandy

[joseprfoto]

Great information,but any examples with photos comparations examples in the web?

[NicolasArg]

It would be a different story. I just blew some from my Mamiya up to 40 inches and the sharpness is beyond belief... way better than I anticipated.
Lenny

Thank you Lenny for the input. Exactly what I've been suspecting since the 5d2 hit the market- film aesthetics aside, in order to get some superior to digital results with medium format, a quality drum scanner and a capable operator is a must

[Lenny Eiger]

Thank you Lenny for the input. Exactly what I've been suspecting since the 5d2 hit the market- film aesthetics aside, in order to get some superior to digital results with medium format, a quality drum scanner and a capable operator is a must

You may conclude this. However, I am not ready to make that leap. I have spent a lot of time being wrong about my conclusions. I would need some direct experience, testing and shooting and printing myself, before I will make that judgement.

I don't think much of most of the consumer-level flatbeds, but I will note that, to be fair, some folks are getting much better results than others. Operator skill is also important there as well, it would appear.

However, I also think that this type if discussion is quite a minefield. Every time someone comes up with something I think is ludicrous, I go look at their images and often they are trying to do accomplish something in their printing I would never consider. There are a lot of things that will work fine for one person and not another.

Lenny

[tuco]

A couple of comments .

First, Pentax 67 optics don't come close to Mamiya 711. I once owned both systems at the same time and in my comparisons, which involved both real life photography and tests with targets, Mamiay 7II lenses gave between 25-45% more detail than Pentax 67 lenses.

Sandy

How did you eliminate the Pentax 6x7 mirror vibration from those tests to get just the lens performance? Also, the guys who have been testing Pentax 6x7 lenses on the new 645D say there are differences in copies of the same lens.

[omegaslast]

Ive seen mamiya 7II 2400 dpi epson v700 scans vs canon 5d mk2 shots and the mamiya 7 II wins hands down in sharpness. canon 5d mk2 was using 50mm f1.4

6x7cm = 5670 x 6612, yes the v700 is interpolating because is not resolving true 2400dpi, but the 5d mk2 is not even close to a true 21 megapixel camera, so the 5616 x 3744 is heavily interpolated, probably more so than the 2400dpi of a 6x7 negative.

I used to have a 5d mk2, now have a mamiya 7II, maybe ill borrow one of my friends 5d mk2s and do some comparison tests with a v700 scanner. (80mm f4 mamiya vs 50mm f1.4 canon is as close as ill be able to get for fov).

I dont think it would even be close.. This isnt even taking into account the fact that medium format has way better depth of field, film has color that is simply impossible with digital to replicate, and film has much better dynamic range.

[sanking]

How did you eliminate the Pentax 6x7 mirror vibration from those tests to get just the lens performance? Also, the guys who have been testing Pentax 6x7 lenses on the new 645D say there are differences in copies of the same lens.

The Pentax I owned was the last model produced, 67 II I believe, and it had a mirror lock down feature. I always used this when testing lenses. The Pentax lenses were ok, just not up to the Mamiya optics. The Pentax 67 line of lenses is much older, plus the Mamiya lens designers did not have to worry about a mirror.

Sandy

[Corran]

Which lenses and what model versions are very important.

I would contend that the newest models of the 55mm and 200mm Pentax lenses are probably as good or close to the Mamiya, and many say the newest 105mm is as well though I never shot that one much except wide-open so I can't say myself. The 90mm f/2.8 LS was also a great performer.

With a converter to Nikon F-mount I tested the Pentax 67 200mm lens directly against the Nikon Micro-Nikkor 200mm on my D700 and D90 and the Pentax was sharper, hands down, at any aperture, and on film it was always consistently excellent on the whole shot everywhere. The 55mm was the same story.

[renes]

For best results scanning a 6X9 cm slide you need a drum scan at 4000 dpi or more. Neither Imacon nor LS-8000 or LS-9000 can get the shadow detail that a good drum scan will give you. Epson V700/V750 won't come close to a drum scanner in either resolution or shadow detail, and loses to the Imacon in resolution (though not by as much as price differential would suggest).
Sandy

For best results scanning a 6X9 cm slide you need a drum scan at 4000 dpi or more. Neither Imacon nor LS-8000 or LS-9000 can get the shadow detail that a good drum scan will give you. Epson V700/V750 won't come close to a drum scanner in either resolution or shadow detail, and loses to the Imacon in resolution (though not by as much as price differential would suggest).

Sandy

Explain it please: if you want to have 20x28" (50x70cm) enlargement from 6x9 b&w film scanned on drum in 4000dpi (its highest resolution), you will get much bigger enlargement, will you? For 50x70cm size a sufficient ans appropriate resolution is 2300dpi. Is it better to scan it in 4000dpi and to scale the file later to 50x70cm size (with some lost resolution and details) than to scan the film in 2300dpi without scaling? Which scanning method is better and why?

[keithwms]

Is it better to scan it in 4000dpi and to scale the file later to 50x70cm size (with some lost resolution and details) than to scan the film in 2300dpi without scaling? Which scanning method is better and why?

With a drum scan it isn't quite so important... this is really a much bigger issue with flatbed scanning. Because of the sensors they use, flatbeds introduce a good bit of sensor noise into the scans, and so it is common practice to 'oversample' i.e. to multiscan and to scan at highest possible resolution and then reduce the size of the scanned file to suit the print. This has the effect of averaging out the noise and producing a cleaner result.

In contrast, a [true] drum scanner has a very low-noise photomultiplier sensor and this isn't so much an issue. It also has no imaging lens (it's only there to collect light, not to image it), so you also don't get lens artifacts with a drum.

That said, with a drum, you can scan down to the grain/dye clumps etc and tune the aperture so that graininess is minimized, so for that reason you may want to scan to the max and reduce the size afterwards.

I'm not an expert but that's my quick 5 cent explanation