On Monday, 15 May, we will be publishing a major comparison between several DSLRs and medium format backs. These tests were conducted by Bill Atkinson, Charlie Cramer and Michael Reichmann.

A disk will be made available for purchase containing some 4GB of raw files from all of the cameras, backs and lenses tested.

This forum is for discussion of that article, the test disk, and the files. Readers are welcome to voice their opinions and observations, and Bill, Charlie and I will attempt to provide feedback.

The site's usual rules regarding adult discourse will of course apply.

Michael

Thankyou for getting all that together in the same place at the same time !

I've given up on extreme pixel peeping this last year concentrating instead on my subjects and what my clients think, but at the same time it's hard not to pine after one of those set-ups where if you take the time the result is unreal.

If I were a landscape photographer I think I would get a second mortgage on the kids to get a hold of the P45, but the work I do is well covered by the 1DSII.

Maybe a P25 just for the weekend with my old V system, sooner or later the price must come down !

Looking forward to getting the disk and peeping at the raws,
David.

Michael and the others,

Thanks a lot for this comparison.

Regards,
Bernard

GREAT article. Shows how difficult this is to produce (the bit about sharpening is a case in point). Also the role of the RAW converter. I too have been pretty pleased with the "film like" quality of RAW Developer. As for the film, I don't like grain (seems like non image forming stuff) so I guess over the years, I've developed a preference for that "digital look" (heck, we can add noise). I know Bill's "the man" when it comes to scanning on his Tango. We spent a few hours years ago comparing a scan off his Tango with an Imacon 848 (the Tango was MUCH better but it cost a lot more). The results from the Canon was really interesting! All in all, a very telling piece. I'm sure once users get their hands on the RAW data, the "results" might be all over the map (yup, you really DO want to keep those RAWs, it's amazing how much better the processed data can be by a software tweak).

Great report by top people using top equipment. Thank you.

I know you were attempting to include that Scanning Back, but to me, if the overall goal was to test Resolution, it would appear that the best method to test this would have been to shoot this test with STROBE, in a darkened room, with modeling lamps turned off, and with the mirror raised.

Did you at least raise the mirrors, when you shot the test with hot lights?

And what type of tripod? The H1 is notorious for Mirror Slap. Testing this, in this manner, with hot lights instead of strobe, calls the entire test into question.

Since the Scanning Back is such an oddball product, why not test everything else with strobe, and then use the Scanning Back only with hot lights?

All it takes is a tiny bit of mirror slap, and one back looks less sharp than the others, which completely invalidates the test. This mirror slap of the H1, to me, is its major Achilles Heel, and should be factored in, if you're going to the trouble of testing on this scale.

Just wondering,

Mark Tucker

" A heavy studio tripod, mirror lockup and self-timers or cable releases were used for all exposures. "

Just because Bill decided that he could run from behind the camera to in front of it in 1/500 sec for the group shot doesn't mean that we didn't know how to use the self timer and MLU.

Michael

But my point is: To the average reader of your website, or your DVD business, they do not realize that they MUST raise the mirror each and every time, in order to get the utmost resolution out of these backs. Or, they must use strobe. The H1 is one of the worst cameras ever designed, for handheld work, due to the mirror slap. You cannot expect ultimate resolution ouf of any back, with the H1, handheld, unless you're on a tripod, and shooting at least 1/500th, if that.

I know this gets somewhat outside of the parameters of the test, since it was directed more at the backs than the cameras, but still, I would hate for someone to buy an H1 for use on any back, and not be firmly warned about the H1 mirror. The camera truly should be recalled, for this one issue alone.

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Another issue for EVERY user of a PhaseOne P25, is the Voltage Issue in the Apple Powerbooks. This could affect the ability for the P25 to sync up properly with ANY Apple laptop, but especially the new Intel Powerbooks. There is not enough voltage there, in the laptop port. You MUST purchase the optional Firewire device from PhaseOne, in order to have RELIABLE tethering to any Apple laptop.

Sorry to get off topic, but would this be an issue with a 1DSII tethered ?

I just ordered a new Powerbook...

I've powered the P25 from a 12" and 17" Powerbook on numerous occasions with no difficulty.

The new Macbook Pros are a different story. Becuase of the built-in web camera the Firewire port doesn't provide enough juice. But a simpler solution is to simply set the back to run off battery when tethered rather than use Autoselect.

It's not a really satisfactory solution for long tethered shooting sessions, but a lot less expensive than Phase One's new adapter.

Michael

Maybe, that's why it's mentioned not only within this article, but within literally any article Michael is releasing towards this topic? Or do you want to say, that the average reader is not able to read? I don't get your point here. Maybe you schould read it before starting murring around.

So you think, the average reader of this website is working with a digital medium format back? If not, why he MUST know details of handling? I don't get your point here, either.

I had my P25 fail in a job last week, when tethering to a MacBook Pro 15, using CaptureOne 3.74. In doing diagnostics, we checked our 1ds2 with the same setup, and it worked great. The problem occurred only with the P25.

Supposedly, the P45 has a method to run off the battery, without having to buy that optional device from PhaseOne.

Yet one more quirky thing about medium format, as opposed to Canon, which just seems to run under most any conditions.