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07-10-2012, 05:24 PM   #3061
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QuoteOriginally posted by NickLarsson Quote
Neophyte question : is a lens as thin as the DA40 XS would be possible on other mounts ?
Lenses with focal lengths close to the flange focal length (actually slightly shorter as the back of the lens extends inside the mount) can be made very small, because they don't need retrofocus groups (for shorter focal lengths) or telephoto extension (for longer focal lengths). 40mm happens to fit right in this sweet spot for the K-mount (having a not particularly fast aperture doesn't hurt either).

So yes, in theory they can make lenses as small, but the focal length for the theoretical minimum size lens will vary between mounts. Notice all the pancake lenses for mirrorless cameras have short focal lengths clustered near their flange focal lengths.

Of course you also have to consider whatever complicated designs are needed for various focal length/aperture/sensor size combinations.


Last edited by Cannikin; 07-10-2012 at 06:05 PM.
07-10-2012, 06:22 PM   #3062
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QuoteOriginally posted by Cannikin Quote
So yes, in theory they can make lenses as small, but the focal length for the theoretical minimum size lens will vary between mounts.
Nikon could probably do it. Canon's new 40mm "pancake" is considerably thicker, probably because all Canon AF lenses need to have a built-in focusing motor.

Of course, neither of these would be stabilized.
07-10-2012, 06:25 PM   #3063
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QuoteOriginally posted by Cannikin Quote
Lenses with focal lengths close to the flange focal length (actually slightly shorter as the back of the lens extends inside the mount) can be made very small, because they don't need retrofocus groups (for shorter focal lengths) or telephoto extension (for longer focal lengths). 40mm happens to fit right in this sweet spot for the K-mount (having a not particularly fast aperture doesn't hurt either).

So yes, in theory they can make lenses as small, but the focal length for the theoretical minimum size lens will vary between mounts. Notice all the pancake lenses for mirrorless cameras have short focal lengths clustered near their flange focal lengths.

Of course you also have to consider whatever complicated designs are needed for various focal length/aperture/sensor size combinations.
It's clear, thanks
07-11-2012, 06:18 AM   #3064
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QuoteOriginally posted by ElJamoquio Quote
Those lenses on a FF camera would be about 1.8. The front element is about the same size as one that's 1.8.

You should use the canon 0.95 or Leica 0.95 (don't remember the exact numbers) and start from there. You're talking serious cash, several thousand is about right.
the Leaica 50 0.95 has a retail of $10000, and a 1 year wait list. Because of this copies on the used market regularly go for $14000. Insane huh. The Canon was also a rangefinder lens, using the ridiculously rare S mount, though most about now have been converted to M mount. Freakin huge lens too. these are all at least 37 years old (the & series RF was dropped in 75) they go from $1600-$4000 depending on condition and your luck on ebay

07-12-2012, 08:51 AM   #3065
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OK, not long ago I was strongly rejecting the possibility of an M-mount DSLR, as this rangefinder mount does not leave the required mirror clearance (why would it? It's a rangefinder...)
And few minutes ago I was reading this:
Fujifilm gives more details of X-system lenses and accessories: Digital Photography Review
"The adapter includes a dual-function gauge so that you can check that the lens doesn't protrude too far into the body[...]". So even a MILC can have such troubles with M-mount lenses.
07-12-2012, 09:53 AM   #3066
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QuoteOriginally posted by Kunzite Quote
OK, not long ago I was strongly rejecting the possibility of an M-mount DSLR, as this rangefinder mount does not leave the required mirror clearance (why would it? It's a rangefinder...)
And few minutes ago I was reading this:
Fujifilm gives more details of X-system lenses and accessories: Digital Photography Review
"The adapter includes a dual-function gauge so that you can check that the lens doesn't protrude too far into the body[...]". So even a MILC can have such troubles with M-mount lenses.
the m mountor also includes a guage. it's for the lenses like the Jupiter 12 35mm which have large protruding rear elements (the Jupiter 12 does fit (just) on an M mountor which makes me want one (somewhat). If they had a FF mountor I would jump on it. On film the Jupiter 12 is my favourite RF lens
07-12-2012, 11:28 AM   #3067
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QuoteOriginally posted by Kunzite Quote
OK, not long ago I was strongly rejecting the possibility of an M-mount DSLR, as this rangefinder mount does not leave the required mirror clearance (why would it? It's a rangefinder...)
And few minutes ago I was reading this:
Fujifilm gives more details of X-system lenses and accessories: Digital Photography Review
"The adapter includes a dual-function gauge so that you can check that the lens doesn't protrude too far into the body[...]". So even a MILC can have such troubles with M-mount lenses.
Well that is the punishment for starting with something new and then try to attrackt users with an adapter I guess.

It would be smart to start with a M-mount updated with contacts that just fits all M-lenses to start with.
07-12-2012, 11:47 AM   #3068
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QuoteOriginally posted by RonHendriks1966 Quote
Well that is the punishment for starting with something new and then try to attrackt users with an adapter I guess.

It would be smart to start with a M-mount updated with contacts that just fits all M-lenses to start with.
the big issue is actually with the older LTM lenses vis the m adater for them. The designs like the jupiter 12 are copies of the CZ Biogon 35mm from pre WW2 and have a huge protruding rear element (there are other RF lenses with this type of design as well.)
you can't actually use the Jupiter 12 on an M9 which is native M mount apparently. it works ok on the film cameras. and the GXR M Mountor

Edit a picture may help



07-12-2012, 02:00 PM   #3069
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QuoteOriginally posted by Kunzite Quote
Nope, I'm not. And I never said the 645D is competing directly against FF, don't make things up. What I claimed is that medium format is their pro solution (or at least as pro as it gets) - and that's a fact.
But you gave that answer to the question, what could pentax do when they want to compete directly with FF of canon and nikon.
You indeed said that the 645D was Pentax pro solution, but since you gave that answer to that question it's very natural to draw the assumption you meant it qould go up against the FF of nikon and canon.
07-12-2012, 02:03 PM   #3070
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QuoteOriginally posted by ElJamoquio Quote
Those lenses on a FF camera would be about 1.8. The front element is about the same size as one that's 1.8.

You should use the canon 0.95 or Leica 0.95 (don't remember the exact numbers) and start from there. You're talking serious cash, several thousand is about right.
mhmm indeed but the fact is that we don't have anything that comes close to that...
07-12-2012, 02:05 PM   #3071
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QuoteOriginally posted by ElJamoquio Quote
Those lenses on a FF camera would be about 1.8. The front element is about the same size as one that's 1.8.

You should use the canon 0.95 or Leica 0.95 (don't remember the exact numbers) and start from there. You're talking serious cash, several thousand is about right.
If i look at Carl Zeiss something that comes very close to Voigtlander for example the CZ 85mm and compare it to canon nikons 85mm i don't see the differnce that much.
07-12-2012, 02:48 PM   #3072
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QuoteOriginally posted by Anvh Quote
But you gave that answer to the question, what could pentax do when they want to compete directly with FF of canon and nikon.
You indeed said that the 645D was Pentax pro solution, but since you gave that answer to that question it's very natural to draw the assumption you meant it qould go up against the FF of nikon and canon.
You really have to work on accuracy.
What you actually said:
QuoteOriginally posted by Anvh Quote
Okay answer me this, if pentax won't make a FF camera but they do want to compete in the professional market how are they going to do that?
This is actually what started it all, lets see if you can up with an answer.
How I answered:
QuoteOriginally posted by Kunzite Quote
Medium format; that's their professional system.
Which, FYI, is a valid answer - the professional market not being limited to the small format - and exactly the path Pentax is following.
07-12-2012, 03:53 PM   #3073
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But dont you think that 645D vs 4D etc. is not a valid comparison, because it addresses different target groups? Dont you think that "competing" in the "Pro segment" might include this (sports, action, lifestyle) shooting ? Havent seen a paparazo with a Hassi etc.
07-12-2012, 04:26 PM   #3074
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QuoteOriginally posted by Anvh Quote
If i look at Carl Zeiss something that comes very close to Voigtlander for example the CZ 85mm and compare it to canon nikons 85mm i don't see the differnce that much.
Is English your primary language? I don't understand what you're trying to convey to me.
07-12-2012, 07:30 PM   #3075
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QuoteOriginally posted by Mehlsack Quote
Havent seen a paparazo with a Hassi etc.
Maybe because they don't need it. Perhaps Pentax, with their 645D system, really does not want to be in the same "pro" field that Canon and Nikon dominate - like you said, sports/action/lifestyle, which some can actually be fulfilled by a good APS-C system.

From this point of view I understand Pentax's stand on providing gear for pro's. It's the gearhead in me that wants that Pentax 35mm to come out. =))
Though well, if chips do get cheaper in the future we will see one from Pentax. but maybe not this year.
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