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03-10-2010, 03:26 AM   #526
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Yeah, yeah, I know, I know, fearview. You're right. But, jeez, I really hope he gets shut down, if only for karmic reasons.

QuoteOriginally posted by falconeye Quote
From the DC Watch JP article...
http://dc.watch.impress.co.jp/img/dcw/docs/353/556/21.jpg

Wasn't this the Pentax patent we once found? To make the view finder smaller by putting a lens between focus screen and prism?

If so, this could mean that Pentax OVF can be build smaller than from the competition. It certainly is a lot smaller than Hasselblad VF
Danke! I was hoping you come along and explain how the trapezoidal prism works...if you could elaborate on how it's different to a normal pentaprism, if there is any difference, that'd be great. Does the trapezoid flip the image the same amount of times as a normal prism?

I posted the dimensions of the 645D and the Canon 1D MK IV a few pages back. About the only area where the 645D is noticeable bigger is (of course) the length, due to the larger mirror box. And it's only 200grams or so heavier, with battery and cards.

03-10-2010, 03:27 AM   #527
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QuoteOriginally posted by fearview Quote
ouww..lithos..chill out..

but im agree.. this time he is really..really..


-- cant find any words in english
Why anybody are carring of what he says ? Looking at his gallery brings out the ugly thruth : he's not a good protographer.

The only 2 blogs / website I respect on hardware matters are The Online Photographer and The Luminous Landscape. They are made by real pros who make a living of their photographic activity, and they are absolutly not brand biased (or state it when they have some specific attachment)
03-10-2010, 03:38 AM   #528
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QuoteOriginally posted by ghelary Quote
Why anybody are carring of what he says ? Looking at his gallery brings out the ugly thruth : he's not a good protographer.

The only 2 blogs / website I respect on hardware matters are The Online Photographer and The Luminous Landscape. They are made by real pros who make a living of their photographic activity, and they are absolutly not brand biased (or state it when they have some specific attachment)
BTW: The Online Photographer: Vapor No More! The Pentax 645D Debuts in Japan
03-10-2010, 03:38 AM   #529
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????.com-???????-PENTAX???????? 645D ?????????????

Those lens prices are pretty reasonable, IMHO. Even a system with several lenses competes in the same price league as the Nikon D3x.

03-10-2010, 03:47 AM   #530
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QuoteOriginally posted by fearview Quote
ouww..lithos..chill out..

but im agree.. this time he is really..really..


-- cant find any words in english
Say it in Indonesian, then! Susilo's down here at the moment, I'll get him to translate . You're right, though.

Fred Miranda Forumites seem to like, though.

Unlike Kenny boy, they like how it's the only MF camera with multi-AF, doesn't require a separate back to purchase, is more portable than your average MF cam, and has a higher-res LCD than any other DMF. And it's probably cheaper than a D3X.
03-10-2010, 03:58 AM   #531
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QuoteOriginally posted by the swede Quote
I hope he gets mail bombed after this! Is that a grown adult man???
He acts like an angry teenager

Meanwhile he is being angry and childish about this, the pros (from every brand) are giving thumbs up to Pentax.

I feel sorry for Ken....it must be hard to be that way. Poor guy.
This. Ken Rockwell's mindless babbling and whining really made me question his age. He should be castrated as soon as possible...he is polluting the gene pool.
03-10-2010, 04:20 AM   #532
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I guess, the most interesting comparison will be

Pentax 645D vs. Leica S2.

Both use the same Kodak Truesense 6m image sensor of about the same size without an AA filter and both cameras are weather-sealed. I thought I may collect some comparative data:

  • Spec: Pentax / Leica:
    .
  • Sensor size: 33x44mm / 30x45mm
  • Sensor technology: Kodak True sense 6 m with no Aa filter (both)
  • MP: 40.0 / 37.5
  • Sensor diagonal: 55mm / 54mm
  • Mount: Pentax 645 / Leica Pro
  • Mount's specified image circle: 70mm (for 41.5x56mm) / 54mm
    (this means that Leica camera and lenses can be made more compact or higher resolution but cannot grow to full MF)
  • Weather seals: "AW" (All Weather) / Sustains 30 minutes of 18 m/s heavy rain
    (I see the German love for precise statements is still alive )
  • Build: Magnesium alloy
  • Weight incl. battery: 1480g / 1410g
  • Size: 156 x 117 x 119 mm / 160 x 120 x 80 mm
  • Size with lens: 187 mm (with DFA 55/2.8) / 173 mm (with Summarit-S 70/2.5)
  • Focal plane shutter: 1/4000s both
  • Focal plane sync time: 1/125s both
  • Leaf shutter sync time: - / 1/500s with selected "CS" lenses
  • Virtual viewfinder size: 0.70x / 0.83x
    (I didn't find the focal length Leica based their 0.86x magnification claim upon; just assuming 63mm or 1.16x the diagonal)
  • Frame rate: 1.1 fps / 1.5 fps
  • Back LCD: 3" 921k / 3" 460k
  • Other: Ease of use of K-7 (hyperprogram etc.) except LV, video, SR / The red dot

Last edited by falconeye; 03-10-2010 at 05:18 AM.
03-10-2010, 04:20 AM   #533
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QuoteOriginally posted by ghelary Quote
The only 2 blogs / website I respect on hardware matters are The Online Photographer and The Luminous Landscape. They are made by real pros who make a living of their photographic activity, and they are absolutly not brand biased (or state it when they have some specific attachment)
Michael Reichman is often referred to as a big Leica (and Canon) fan. With his "K-7 Hands On" non-review (a frighteningly bad hands-on test, written up as a pretty useless opinion piece) he definitely aspired to Ken Rockwell levels of bandwidth waste.

There are some very interesting articles on LL, though. I just don't trust it anymore after M. Reichman insisted he was right despite a lot of criticism towards his "K7 Hands On".

03-10-2010, 04:25 AM   #534
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QuoteOriginally posted by falconeye Quote
  • Frame rate: 1.1 fps / 1.5 fps
I see, the Leica is the clear choice for sports photographers then.

EDIT: Removed my comment regarding SR. Clearly Falk meant the "except" to cover everything that followed it, not just "LV".
03-10-2010, 05:09 AM   #535
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Thanks Falconeye for this quick comparison. I would add the existence of leaf shutter variants to each lens to Leica S2's credit: they are very useful for high speed flash synch (studio photography).

Last edited by Mistral75; 03-10-2010 at 05:43 AM.
03-10-2010, 05:09 AM   #536
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QuoteOriginally posted by lithos Quote
I was hoping you come along and explain how the trapezoidal prism works...if you could elaborate on how it's different to a normal pentaprism, if there is any difference, that'd be great. Does the trapezoid flip the image the same amount of times as a normal prism?
Well, I don't know actually.
Forced to think about it, my wild guess would be that it works a little different from a traditional roof pentaprism with 3 reflections. Looks like it has the same 3 reflections but no roof. I.e., the left/right flip would have to come from the optical system in the ocular and that the prism itself wouldn't actually invert the image orientation.

Also, unlike a pentaprism, the image seems to be focussed (more) before entering the prism, so that it gets smaller along its path and the prism surfaces can be made smaller for 2nd and 3rd reflection surfaces. And magnified by the optical system in the ocular upon exit of the prism.

I searched and found a patent from 1978 hold by "Asahi Kogaku Kogyo Kabushiki" (is this Pentax?) which describes the principle:
Patent US4171888
Seems like Pentax did their homework some 32 years ago

Some difference to the patent: The mirror doesn't seem to be 45 exactly (more like 40). There is a noticeable tilt in the entire optical viewfinder system from mirror to prism exit. I would say that this is a sophisticated piece of engineering.

However, the 645N is even 6mm flatter and needs a larger mirror. Therefore, I guess that this isn't new technology for Pentax at all. The viewfinder in the 645N is described as "Keppler telescope finder", a variant described in the above patent as well. This variant was shown in the patent with mirrors but I believe, the 645N finder has a prism as well.

Last edited by falconeye; 03-10-2010 at 05:28 AM.
03-10-2010, 05:10 AM   #537
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QuoteOriginally posted by ogl Quote
And as I understand you can see this in VF too.

You can probably get that display on the back LCD, but in the viewfinder you will only see the "normal" green bars. Well, that is my guess anyway.
03-10-2010, 05:15 AM   #538
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QuoteOriginally posted by Mistral75 Quote
I would add the existence of leaf shutter variants to each lens to Leica S2's credit
It was mentioned under Shutter. I reformatted to make it more visible now.
03-10-2010, 05:18 AM   #539
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QuoteOriginally posted by lithos Quote
The more I think about it, the 645D is pure Pentax
I agree. This is exactly the camera Pentax could make with their existing strengths.... and it is the camera they finally did have the will to make.

QuoteOriginally posted by lithos Quote
The 645D will probably have best-in-class AF - WE'RE ALL DOOMED! THE END TIMES ARE UPON US!
Auto-focus worked just fine on the film 645 models, so I see no reason to expect any differently here.

QuoteOriginally posted by Fl_Gulfer Quote
No SR system?
This camera will be on a tripod more times than not. It is not designed for low light slow shutter hand-held work. Besides, the larger weight and bulk work to stabilise shots. I have only a little experience with the 645N but I was surprised at how steady I could hold the camera and how sharp the images were.

SR would be nice, however, from a marketing point of view and for those few times when it helps. But the smaller the camera, the more important it is.
03-10-2010, 05:19 AM   #540
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QuoteOriginally posted by Boucicaut Quote
This. Ken Rockwell's mindless babbling and whining really made me question his age. He should be castrated as soon as possible...he is polluting the gene pool.
I was waiting for someone like Ken to start bitching about how user-friendly the camera is - about how genius is insulted by things like Program modes, or Multi-AF points, or, heaven forbid! multipattern metering.

I could understand if the camera cost more than the equivalent Hassy, or even Mamiya. But it's significantly less than both. Much less. But expect more bitching about how it's over-engineered for an MF camera.

And, like Kenny, I'm sure this bitching will come from those who spend time extolling the virtues of all the features and technology on the Nikon or Canon single-digit cameras.

I mean, it's still 40 AF points behind the D3, and 34 behind the Canon 1D Mk IV. If it really means that much to people.
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