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11-20-2014, 11:47 AM   #16
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QuoteOriginally posted by FantasticMrFox Quote
And how exactly would an adapter work to turn MF lenses into AF lenses? Genuine question.
Art of magic.. haha.. that is mmmm impossible simply because MF lenses doesnt have any motor inside so there is no way to move that rings unless using the hand...

I still think that Februarty at CP+ will be Pentax last time to catch up with FF camera.. Sony is just kicking hard the a great $1600 price, Canikons are already working on their next models so.. what is Pentax waiting?? the next planet alignment?? FF IBIS is possieble as Sony just did.. SO.. what is the excuse??

11-20-2014, 11:54 AM   #17
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QuoteOriginally posted by kooks Quote
Art of magic.. haha.. that is mmmm impossible simply because MF lenses doesnt have any motor inside so there is no way to move that rings unless using the hand...
It has been suggested by others in this thread, that's why I was asking - I find it pretty unlikely too

QuoteQuote:
I still think that Februarty at CP+ will be Pentax last time to catch up with FF camera.. Sony is just kicking hard the a great $1600 price, Canikons are already working on their next models so.. what is Pentax waiting?? the next planet alignment?? FF IBIS is possieble as Sony just did.. SO.. what is the excuse??
According to another thread on PF from today someone has got an 'official' confirmation by a Ricoh representative at a French fair that Pentax will release FF in 2015
11-20-2014, 11:55 AM   #18
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QuoteOriginally posted by FantasticMrFox Quote
And how exactly would an adapter work to turn MF lenses into AF lenses? Genuine question.
The only way would be to change the Z axis. Sony had a patent for moving the sensor to focus any lens by moving the sensor rather than changing the focus on the lens. Pentax had a TC that turned manual lenses into AF. I assume they did the same thing, but they must have altered the position of the optical element in the TC. I've never seen one in action. An adapter, with no glass, would have to alter the length of the tube to achieve the same function(seems unlikely).

Last edited by kenafein; 11-20-2014 at 12:05 PM.
11-20-2014, 12:08 PM   #19
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I could care less about AF with a MF lens as long as the MILC camera had both SR and EV focus peaking (like the new Sony clearly does). That would be more than enough for me. Not thinking of switching, but it would be nice to get a better platform for legacy glass -- without a split-focus, OVF's in the digital age are hopeless for most people for manual focusing.

M

11-20-2014, 12:24 PM   #20
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One idea with AF with MF lenses is that instead of the lens moving forward and backward to focus, the sensor would move instead. Not sure how well this works and what IQ impact this might have, especially with internal focus lenses. Or if the adapter uses glass elements it might be possible to do something. But this is one of those clever ideas that I doubt would ever be realized. Too much work for something that isn't directly profitable.
11-20-2014, 05:14 PM   #21
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QuoteOriginally posted by MJSfoto1956 Quote
Agreed. That is a bargain. CaNikon should be concerned.
Indeed! If not for the EVF and lack of weather seals, I may well have bought a A7 over my K-3. The EVF, however, gave me a headache after only about 15 seconds of use.


Steve

---------- Post added 11-20-14 at 04:17 PM ----------

QuoteOriginally posted by FantasticMrFox Quote
And how exactly would an adapter work to turn MF lenses into AF lenses? Genuine question.
IIRC, there is a Pentax TC that does just that. AF drive and focus helicoid are built into the TC.


Steve

---------- Post added 11-20-14 at 04:23 PM ----------

QuoteOriginally posted by MJSfoto1956 Quote
without a split-focus, OVF's in the digital age are hopeless for most people for manual focusing.
This is so true, but is hardly a characteristic of digital cameras. The problem has been with us since the first PDAF systems on 35mm film cameras. We have dim finders with poor focus sensitivity because of the half-silvered mirror of the AF system. A manual focus dSLR could have a viewfinder comparable to best film cameras of thirty years ago.


Steve
11-20-2014, 05:42 PM   #22
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QuoteOriginally posted by MJSfoto1956 Quote
...and wouldn't it be sweet if that adapter ALSO gave you tilt and shift? (that would be killer)

M
It appears that the sensor can already offer that possibility.

Pentax cameras have limited shift capabilities due to Sensor Shift, but this Sony can also correct for tilt. I don't see why that can't be utilized to manually offer a limited tilt lens feature.
11-20-2014, 06:15 PM   #23
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QuoteOriginally posted by bossa Quote
It appears that the sensor can already offer that possibility.
Having used large format cameras for years, I can assure you that the limited shift available in the Pentax sensor (I have used it btw) is simply not enough. The kinds of movements needed are way beyond what is possible with just sensor movements.

M

11-20-2014, 09:55 PM   #24
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QuoteOriginally posted by MJSfoto1956 Quote
Having used large format cameras for years, I can assure you that the limited shift available in the Pentax sensor (I have used it btw) is simply not enough. The kinds of movements needed are way beyond what is possible with just sensor movements.

M
Hence my usage of the word limited.

I use a Nikon PC-E 24mm on my D810 but it's not really the best optically. Any way of squeezing a little more out a a great prime would be welcome.
11-20-2014, 10:38 PM   #25
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QuoteOriginally posted by bossa Quote
It appears that the sensor can already offer that possibility.

Pentax cameras have limited shift capabilities due to Sensor Shift, but this Sony can also correct for tilt. I don't see why that can't be utilized to manually offer a limited tilt lens feature.
With a FF sensor in the E-mount the sensor can't move much before vignetting starts to be a problem.
All IBIS system correct for tilt by moving sensor up/down and left right, The extra 2 axis of the 5-axis stabilisation do is correcting x- and y-movement of the camera.
11-20-2014, 10:39 PM   #26
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The reasons to not jump to the Sony FF mirrorless are shrinking. I'm liking the concept, my FF lenses are too, but I'll hold out just a bit longer to see what Pentax is planning. My guess is that the value won't beat this $1600 gem.
11-20-2014, 10:43 PM   #27
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I wonder how low the prices of used A7's will drop.... hmmmm
11-21-2014, 01:38 PM   #28
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QuoteOriginally posted by jeffshaddix Quote
The reasons to not jump to the Sony FF mirrorless are shrinking.
Try and compare. The A7 cameras are nice, but the form factor and EVF may take some getting used to. BTW, any word on whether they managed to muffle that shutter? The A7r I demo'ed was even louder than my K10D.


Steve
11-21-2014, 01:40 PM   #29
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QuoteOriginally posted by jeffshaddix Quote
The reasons to not jump to the Sony FF mirrorless are shrinking. I'm liking the concept, my FF lenses are too, but I'll hold out just a bit longer to see what Pentax is planning. My guess is that the value won't beat this $1600 gem.
That still native AF lenses echosystem for me:
- No good cheap lenses
- No fast zoom and a few primes
- No real tele.

I don't want an adapter and I'am not that much after playing with manual lenses.
11-21-2014, 03:06 PM   #30
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the a7r has a minimum .163 second shutter delay, and it's noisy... i'd guess that this a7 camera will have an electronic shutter?
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