Why use a 135format lens mount?

Loyalty Indeed. I bought a Pentax DSLR because my old lenses would fit it, and I was always happy with my Pentax 35mm bodies.

I think we have a confusion between a mount and Camera design here, as a Mount is just that, a mount. What you do with it is the difference.
Plus, lens design is also a factor, as is the market.

What we have to remember is that in the early years Digital was extremely expensive, and an unknown concept. So to tempt the early takers of Digital, which would have been Pro's, the easiest way would have been to keep the same mount for their lenses, rather than attempt to bring in a whole new system which could potentially bomb (remember APS SLR's? - you get the idea)
In the meantime Film was still selling strongly and great numbers of enthusiasts would have had a range of lenses that cost a not in inconsiderable amount to them (ie us!) To totally change systems would have been not viable. Yes I know Canon totally change their system in the eighties, but that was a gamble which might not have worked, but of course they were lucky!
This was not helped by the length these "old" mounts had been around. We all know about the K-mount, but you also had the Minolta Alpha mount which is from the seventies, and Nikons F-mount dates back to 1959!
So, taking this into account it would have been suicide for any of the makes not to adopt their current mounts (Olympus excepted, but I will get to that)
It was only until about 2002/03 that digital took off with the consumer, with the first sub £1000 DSLR's hitting the market and with it the bonus of using their existing lenses.
Now, of course at the time, a great number of "consumer" lenses were fine with film, but started to fall short - IQ wise - with digital, but even this only started when the pixel number went up to 10mp+
Olympus, of course saw this coming and knew that a great many lenses out there were not designed for digital, due to the way the light hit the lens, so bit the bullet, trashed the OM mount and created what we call 4/3rds. This at the time was a brave move, but a logical one, and by making it "open source" with the hope that other brands would join in (only Panasonic and Leica did though)
However, time is great when it comes to advancement, and other manufactures started to design and make lenses which, although could still be used with film, were optimised for digital. Things like aspherical lenses started to appear.
This, along with advances with sensors (not good for old lenses), is where we are at now.

Only recently have we seen a new range of mounts suddenly appear, but this is due to the new breed of mirrorless cameras. You can understand though why these new cameras don't use existing mounts, as can you imagine if Sony kept the Alpha mount for the NEX camera, some dopey so and so would put a full alpha mount lens (or attempt to) on the body, and damage the sensor. But the manufactures are canny, and will sell an adapter so you can use your legacy lenses (with limitations)

So there you go, my view on why we still have the mounts we have.

I meant DSLRs designed to have a smaller registration distance, but I didn't mean micro4/3rds so I made up a new word...

Iain thank you for the history lesson.

I've already said my thing and there is little to discuss about more.

Ah okay perfect, I thought you meant mirrorless so good that I asked

It would indeed be a fun idea but complicated, just an extention tube/adapter would be better I think since that would make the camera smaller and lighter.

You're welcome mate

The puzzling one is that Minolta invested a good deal of money in their APS SLR, and produced a surprisingly complete set of lenses to go with it. They won't, however, work on the Sony cropped sensor bodies. Given that the sensor is the same size as an APS frame why on earth didn't they consider this? It'd give them a chance to force people to buy a whole new set of lenses when they went from cropped to full frame!

I will admit to a sneaking urge to buy a Vectis S1, if I ever see a stupidly cheap example. I can see them turning collectible like older cameras which used now-unavailable film formats, especially given the low sales figures (APS being principally aimed at point and shoot users and in any case hitting the market just as digital was gaining ground).

Just a little correction - aspherical lenses have been around for much longer than that. For instance: http://www.bdimitrov.de/kmp/lenses/primes/ultra-wide/K15f3.5-i.html

Dan

Indeed Matt, I must say the camera's looks interesting and also really small.
Would have loved t see that Minolta would have embraced the mount for their digital cameras but sadly they didn't.

Considering that the number of DSLR users who never change their lens at all its remarkable that so many manufacturers have even bothered to develop new mounts. Clearly its far more about marketing than actual sales...

average consumer :

- "oooh, I'll buy this shiny camera in the shop because the man says then I will be able to take the best pictures, and I can change the lenses at a later stage, isn't that a great idea"
- pause of 5 years
- still just got the kit lens on the front - not even a hood
- takes more photos on their iPhone than the DSLR


Any camera manufacturer who can see more than 6 months into the future will be looking at why an iPhone4 (etc) costs more than an entry-level DSLR (and is bigger and heavier than than a P&S) and why more pictures were taken at Glastonbury on them than all other types of cameras combined (arbitrary statement based on the facebook posts I've seen - and that includes a lot of people paid to be there taking pictures of their work not just punters!). Would you then spend any time developing a new, entry-level, lens mount system designed for the long-term?

4/3'rds - developed as a "digital only" mount is already dead for DSLR's, it may come back for Video in the next year (to compete with RED & 5D's etc) but is unlikely to succeed long-term.

I stand corrected, however it was only Aspherical combined with Extra lower dispertion lenses that came to the fore, along with computerisation of said lenses that I should have said, rather than just saying aspherical

I think this may be as much due to technology bringing the price of design of this sort of lens down to a more 'consumer' level (the 31mm Limited is an AL ED lens, designed for film), but it certainly pushed the process along once people could easily inspect their images for distortion and CA at such high magnifications.

Dan

Exactly Daniel, time will produce better product, and of course prices will come down due to these advances. Its not just the fact that people could inspect items at high magnification, it is the fact that they could in the first place.
Any product that has been designed in the first place, will eventually come down to a level that most people could own one, be it a car, a television, a microwave oven, or an AL ED lens. They did'nt arrive overnight, but when they did first appear, the mere "ordinary" person did not, or could not obtain them in the first place.

Yes the AL ED was around, but not on consumer lenses. Now AL and ED is commonplace.

For that matter why brother develop new lenses then?
That's far harder then changing a register of a mount

No one is talking about that I believe and actually I was talking about the opposite then entry-level.

The k-mount is great for 135 format but less so great on APS-C.
They used that register distance for the mount because it comes close to 50mm which is regard as "normal" on 135 format and you got 50mm f/1.2 and f/1.4 lenses for that, great super but with APS-C 35mm is closer to normal so if they bring the register closer to that you can get very fast lenses at that range for a good price. For example if they use 36mm that's 1cm shorter then the K-Mount they could make 35mm f/0.9 lenses.
Also it easier to design other faster lenses as well.
That's all needed to compensate for the lost off DOF you get when using smaller format.

Funny enough Olympus had more than twice the market share in 2008 than Pentax

Ah I see what you are getting at now - the shorter distance gives you faster lenses. I couldn't see what great advantage shaving a few mm off a 50-135 would be! I still think it would be better to design better glass (especially more F2.8, no more F4 please...) in the first place than chasing ultra-low F-stops.

Or even better, go FF then you can gather even more light in the first place... (runs, hides...:lol. More seriously, things like an electronic shutter & fully EVIL would allow you to significantly reduce the registration distance, but this is still a few years away - in the past, camera developments started at the top end and later trickled-down, but unusually this is something that's coming-up in the opposite direction, due to both technology and sales (when 35mm DSLR's were developed most profitable cameras were bought by Pros, the mass market wasn't important - now its the other way round)

Didn't do them any good in the DSLR market, did it? They did realise that chasing the "indistinguisable identikit black DSLR" market is fruitless, and brought out the E-P range - with possibly the best looking bodies anyone has come up with in maybe 30 years! Pitty the camera doesn't live up to the looks, but on the bright side its existance did (somewhat indirectly) lead me to DSLR's and Pentax.


There's a lot of good things said in this thread which doesn't directly tackle your question, but does show why a new mount is a Bad Idea (tm) especially when you look at the failures of the past.


Anyway, we should know at/by Photokina what Pentax is up to - the only thing that is definate is that at least 1/3 of Pentax users will very vocally hate whichever direction they go (stay where they are, go FF, EVIL, m4/3, etc etc...)