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02-28-2016, 08:52 AM   #16
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QuoteOriginally posted by i83N Quote
”Floating Mirror Structure
In order to accommodate the 35mm full-frame image sensor and cover the light flux of the large viewfinder with a nearly 100-percent field of view, it was necessary to increase the size of the main mirror and mirror box. To minimize the size of the mirror box, PENTAX has developed a new mechanism that retracts the main mirror as it swings upwards.”

Interesting innovation. Hope it won’t provide extra shaking and mirror slap.
Pentax did the same thing with the LX mirror assembly. The LX was the only 35mm film era Pentax that did not suffer mirror slap to some degree.

Last edited by Wheatfield; 03-16-2016 at 08:42 PM.
02-28-2016, 05:22 PM   #17
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Why,oh god, Why didn't they use it on the Pentax 67...
02-29-2016, 08:11 PM   #18
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Sure enough, the LX has a full-size mirror, where the MX does not. The LX must slide the mirror up like the K-1 mirror to clear the lenses, but the K-1 has to do it more severely due to the Pentax-DA lenses.

I checked this by putting a 300mm lens on both the LX and MX, and stopping down to f/32. On the LX, there's no cropping of the image at the top of the finder. On the MX, there is. (But not as severe as the same would be on my Topcon Super-D, which has severe mirror crop.)
03-16-2016, 08:41 PM   #19
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QuoteOriginally posted by Digitalis Quote
Why,oh god, Why didn't they use it on the Pentax 67...
Didn't need it. The 67 mirror was actually very smooth.

03-16-2016, 09:37 PM   #20
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Early on somebody (several) complained that the K-1 doesn't have enough invention in it.

I for one am very appreciative of the innovation the K-1 does contain. The fact that Pentax Ricoh was persistent at making it a small package (relative to the FF DSLR competition) and has continued to innovate their technology such as 5-axis SR and motion compensation for pixel shift… means that I will feel compelled to purchase one when I am able. (Perhaps the real invention was the unforeseen concept that they could introduce it at the price they are.)
03-16-2016, 09:43 PM   #21
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QuoteOriginally posted by One3rdEV Quote
Early on somebody (several) complained that the K-1 doesn't have enough invention in it.
I don't know, I do remember seeing people complain it was "just another DSLR" with nothing new, but the more we see the more 'innovative" this camera gets. Sure the focus by mind control feature did not make it into the final firmware but the list of 'new' or 'improved' items is quite extensive. I might hazard saying it has the most innovation of any Pentax camera since digital.
03-17-2016, 03:33 AM   #22
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QuoteOriginally posted by Digitalis Quote
Incorrect - while it is true that the flange is unchanged: the mirror for a full format camera is much bigger than the mirror used in APS-C camera bodies. Certain lenses like the 40mm f/2.8 XS, DA21 or the DA15 have rear elements that protrude further than FA lenses do into the mirror box. The larger mirror, if it remained on its typical arc of movement would in all probability strike the rear element or the surrounding area of certain DA lenses when they are focused at infinity. So Pentax sought to modify the arc of the mirror so DA lenses could be used - it is an elegant solution.

The other upshot of this is that some of the energy from the mirrors upward momentum will be redirected and damped through its movement arc - reducing the effects of mirror slap.
To my knowledge no current DA lens violates the K mount specification to protrude deeper than it should ... excluding that prototype they showed with k-01 but did not release and maybe the XS (I've never seen one, maybe it protrudes deeper than the 40 ltd) since these two were meant for mirrorless.

SMC-M 20mm for example protrudes little more than the 15 and 21 ltd lenses. I think the rear baffle on 20-40 ltd is the one that protrudes most of all DA lenses but it still clears the mirror on my ME Super

Some DA lenses are listed as incompatible with the 1.4x TC, but it does not mean they are incompatible with the K mount - most of the wide legacy FA lenses are also listed as incompatible with the TC.

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