I can comment on the Pentax 645, but only give a few remarks on the Mamiya 645 since I do not own one. Both the P645 and the M645 Pro are fine, versatile cameras. If you want interchangeable backs or low cost polaroid capability, then the Mamiya is THE choice between these two cameras. The P645 does not possess these particular features.
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The Pentax does not have interchangeable viewfinders, but it does have an excellent right angle view attachment. In awkward positions you can rotate this viewfinder to a more comfortable position. Speaking of viewfinders, some eyeglass wearers have complained that the P645 does not have enough eye relief. The diopter eyepiece setting also tends to move on you, so you have to watch its placement occasionally.
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I personally prefer groundglass as my only focussing aid, however the P645 has several interchangeable screens, of which I find the grid screen (UG-20) the most useful. Focussing is easy since the view is bright and contrasty.
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The metering is lower center-weighted and covers most situations.
The most sensitive metering location is one-third up from the bottom center of the viewscreen. However, I would like a built in spotmeter which the Mamiya 645 has - it would be more convenient. The metering sensitivity is from EV 3 to 19. This isn't as good as most 35mm SLRs, but it's adequate for most lighting situations.
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The lenses of the P645 are very well made and give sharp, contrasty images. You can also attach many P67 lenses and still have aperture priority automation. However, the Mamiya lens line is quite extensive so one can't say Pentax is better than Mamiya in lens selection.
I have one additional comment on the depth of focus scales on Pentax 645 lenses. IMHO, Pentax uses a rather generous calculation on how much depth of field you have for a given aperture. For example, on the 45mm lens, the depth of field at F/22 is from 4 feet to infinity. IMHO, 6 feet to infinity gives better foreground to background sharpness, especially if you do enlargements.
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The P645 is, IMHO, a rugged camera built more for field use than for studio use. I've *ahem* had my camera fall down with my tripod several feet landing on some rocks, in the middle of an autumn rainstorm. I wiped down the camera with a clean cloth since it had mud and water on the pentaprism and left side. Fortunately, no water seeped between the lens mount and body. The camera landed on its pentaprism so the lens was spared, but there are scrapes on top.
Functionally, I've had absolutely no problems at all since that heart-skipping morning last year.
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Both Metz and of course Pentax flashes work with the P645 TTL
flash mode. Rumor has it that Metz exaggerates its guide numbers more than Pentax, but this is just a rumor.
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Basically, the biggest limitation in my photography has been myself; the Pentax 645 is more than adequate for a creative person who does landscape and nature photography. However, the Mamiya 645 may be a better studio camera, and many fine nature photographers also use it.
Pentax 645 vs Mamiya 645
in Medium Format
Posted
I can comment on the Pentax 645, but only give a few remarks on the Mamiya 645 since I do not own one. Both the P645 and the M645 Pro are fine, versatile cameras. If you want interchangeable backs or low cost polaroid capability, then the Mamiya is THE choice between these two cameras. The P645 does not possess these particular features.
<p>
The Pentax does not have interchangeable viewfinders, but it does have an excellent right angle view attachment. In awkward positions you can rotate this viewfinder to a more comfortable position. Speaking of viewfinders, some eyeglass wearers have complained that the P645 does not have enough eye relief. The diopter eyepiece setting also tends to move on you, so you have to watch its placement occasionally.
<p>
I personally prefer groundglass as my only focussing aid, however the P645 has several interchangeable screens, of which I find the grid screen (UG-20) the most useful. Focussing is easy since the view is bright and contrasty.
<p>
The metering is lower center-weighted and covers most situations.
The most sensitive metering location is one-third up from the bottom center of the viewscreen. However, I would like a built in spotmeter which the Mamiya 645 has - it would be more convenient. The metering sensitivity is from EV 3 to 19. This isn't as good as most 35mm SLRs, but it's adequate for most lighting situations.
<p>
The lenses of the P645 are very well made and give sharp, contrasty images. You can also attach many P67 lenses and still have aperture priority automation. However, the Mamiya lens line is quite extensive so one can't say Pentax is better than Mamiya in lens selection.
I have one additional comment on the depth of focus scales on Pentax 645 lenses. IMHO, Pentax uses a rather generous calculation on how much depth of field you have for a given aperture. For example, on the 45mm lens, the depth of field at F/22 is from 4 feet to infinity. IMHO, 6 feet to infinity gives better foreground to background sharpness, especially if you do enlargements.
<p>
The P645 is, IMHO, a rugged camera built more for field use than for studio use. I've *ahem* had my camera fall down with my tripod several feet landing on some rocks, in the middle of an autumn rainstorm. I wiped down the camera with a clean cloth since it had mud and water on the pentaprism and left side. Fortunately, no water seeped between the lens mount and body. The camera landed on its pentaprism so the lens was spared, but there are scrapes on top.
Functionally, I've had absolutely no problems at all since that heart-skipping morning last year.
<p>
Both Metz and of course Pentax flashes work with the P645 TTL
flash mode. Rumor has it that Metz exaggerates its guide numbers more than Pentax, but this is just a rumor.
<p>
Basically, the biggest limitation in my photography has been myself; the Pentax 645 is more than adequate for a creative person who does landscape and nature photography. However, the Mamiya 645 may be a better studio camera, and many fine nature photographers also use it.
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G.