[quote name='Lomskij' timestamp='1285229109' post='3140']
You mean entry level segment will suffer? :-) As at the moment it rather seems that Nikon and Canon are battling exclusively in the mid-segment (550D/60D/7D and Nikon equiv.) and it's really difficult to believe that EVILs could make an impact there.
On the other hand, I really do not understand Sony's stance here. To me all their product lines are massively overlapping: oversaturated entry segment (2xx/3xx/4xx/5xx), NEX and new SLT's. While the mid segment (where A700 used to be) leaves a yawning gap. Or maybe I'm missing something here.
[/quote]
Actually, many compact shooters used to switch from P&S to small dslr. What seems to eb happenign now is that compact shooters who are looking for a good compact camera, and those that used to seek out entry-level (and mid-level if you like) dslrs, now jump straight to EV-cameras. Many find dslrs too big...
As to Sony: it is all about shelf-space. They have/had the same tactics with their dslrs. For every Nikon or Canon body you see 6 slightly different Sony dslrs, where often even the retailer can't really adequately explain the difference. However, the consumer sees an enormous choice from Sony, and only very little from e.g. Nikon and Canon - that is what it is all about, exposure IOW <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/biggrin.gif' class='bbc_emoticon' alt='  ' />.
Kind regards, Wim
Gear: Canon EOS R with 3 primes and 2 zooms, 4 EF-R adapters, Canon EOS 5 (analog), 9 Canon EF primes, a lone Canon EF zoom, 2 extenders, 2 converters, tubes; Olympus OM-D 1 Mk II & Pen F with 12 primes, 6 zooms, and 3 Metabones EF-MFT adapters ....
[quote name='Brightcolours' timestamp='1285230519' post='3144']
On the other hand, Pentax has never actually been much bigger. And yet it was viable for them to survive. But they do need some better products (like the K5), they need to stop making cameras that only compete with cameras in their own range (to me the K-m, K-x and K-r do not make sense, there should only be one in that segment). What Pentax really could use is a full frame DSLR with K5 characteristics. And then some new primes that do not just focus on compactness, but also in versatility (see Canon's f1.2-1.4-2 range) to cater for a more diverse client circle.
[/quote]
Agreed, AFAIAC, they started going downhill when they left the professional 35 mm slr market 15 to 20 years ago and tried to do commodity goods for the consumer market.
[quote name='inaki' timestamp='1285243138' post='3156']
I don´t think Pentax needs that, to be honest. What they need is to adjust prices and gain visibility, in any case.[/quote]
Visibility is created by having a professional line, that is what many companies seem to forget. It si amonst others about consumer pride: "hey, they do a Formula 1 model, so they must be good" kinda thing.
Quote:To be honest, the best lens map of them all is the Olympus lens range, which is quite well stepped. Nikon-Canon lens map is such a mess and there is so much overlapping that they seem to be a cellphone carrier price plan.
And that is so not good.
I don't understand your comment here. Canon has a very extensive range of lenses, in 4 different categories, which makes ti possible for everybody to choose their poison for the budget they have. Nikon is similar, not entirely there yet at the same level as Canon, but getting closer, and both have possibly a few lenses missing from their range anyway when it comes to very, very specific needs.
Olympus started all over again, as they had to. However, they seem to be abolishing their dslr adventure now, certainly when it comes to lenses. And they still have a limited range, both in their range as well as their market segments.
Kind regards, Wim
Gear: Canon EOS R with 3 primes and 2 zooms, 4 EF-R adapters, Canon EOS 5 (analog), 9 Canon EF primes, a lone Canon EF zoom, 2 extenders, 2 converters, tubes; Olympus OM-D 1 Mk II & Pen F with 12 primes, 6 zooms, and 3 Metabones EF-MFT adapters ....
[quote name='wim' timestamp='1285250841' post='3163']
I don't understand your last statement. As long as the interface to the lens works the same way, I don't see why contrast detection algorithms require different electro-mechanics in a lens. Phase based systems work on predictions, and in difficult situations on a loop-through; a fast contrast AF system will also have to work on predictions and/or ;loop-through, so I do not see how this will affect the electro-mechanics: it is just an interface, at least from an AF POV, to tell the lens where to move to.
If anything, it should be rather simple to create a backward compatible mount, especially for EF and EF-S lenes for Canon, and AFS lenses for Nikon. They would only have to create the appropriate adapter from new mount to old mount, which essentially should just be an extension tube with contacts.
Kind regards, Wim
[/quote]
If it was that simple Sony wouldn't have struggled with their Alpha-mount adapter.
Even the four-thirds gang has issues here.
That said - I don't understand the problem either.
[quote name='Klaus' timestamp='1285251861' post='3168']
If it was that simple Sony wouldn't have struggled with their Alpha-mount adapter.
Even the four-thirds gang has issues here.
That said - I don't understand the problem either.
[/quote]
I guess it might be a matter of the NHI-syndrome (Not Invented Here), as in the different groups developed their own interfaces, with different signals and signal types. I don't think that would be an issue with Nikon or Canon with a long-established methodology, though.
Of course, within a group of companies it gets even trickier, because even the slightest misunderstandings regarding interface protocols may have rather desastrous results, and although camera and optics companies may have worked together on mechanical interfaces in the past, an electric/electronic interface is something completely new to them when it comes to co-operation <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/biggrin.gif' class='bbc_emoticon' alt=' ' />.
Kind regards, Wim
Gear: Canon EOS R with 3 primes and 2 zooms, 4 EF-R adapters, Canon EOS 5 (analog), 9 Canon EF primes, a lone Canon EF zoom, 2 extenders, 2 converters, tubes; Olympus OM-D 1 Mk II & Pen F with 12 primes, 6 zooms, and 3 Metabones EF-MFT adapters ....
[quote name='wim' timestamp='1285250841' post='3163']
I don't understand your last statement. As long as the interface to the lens works the same way, I don't see why contrast detection algorithms require different electro-mechanics in a lens. Phase based systems work on predictions, and in difficult situations on a loop-through; a fast contrast AF system will also have to work on predictions and/or ;loop-through, so I do not see how this will affect the electro-mechanics: it is just an interface, at least from an AF POV, to tell the lens where to move to.
If anything, it should be rather simple to create a backward compatible mount, especially for EF and EF-S lenes for Canon, and AFS lenses for Nikon. They would only have to create the appropriate adapter from new mount to old mount, which essentially should just be an extension tube with contacts.
Kind regards, Wim
[/quote]
It is just a fact, that lenses and their motors/electronics/software are geared towards responding to commands from the PD-AF systems. They can make "steps" which are geared towards being able to see phase difference as quick as possible. And they can respond to "move x amount" and to "move to there".
Contrast AF works different, it just needs a lens to move relatively slowly until it sees contrast going worse again. Then it knows it reached focus.
To achieve this with the PD AF lenses is difficult, the implementations of how the motor is being commanded is just so very different. That is why with ALL manufacturers, we see comparatively slow AF, we see the lenses take actual small steps towards focus and beyond and back. While the manufacturers with the same image processors achieve contrast AF fast and fine with their compact digitals.
Nikon, Canon, Pentax, Olympus, all show slow AF in contrast AF with PD-AF lenses.
Sony does not offer contrast AF, with live view via the main sensor they chose to only offer MF (A5X0 series).
The Sony NEX series does not AF at all with the Sony PD-AF lenses, even when they are SAM or SSM lenses.
Olympus with micro 4/3rds only offers fast contrast AF with the new micro 4/3rds lenses, the older PD-AF lenses either do not AF at all, or offer a slower contrast AF performance.
It is just that way, Wim... lenses designed to respond to a PD-AF protocol (or in-body motors/AF electronics (Pentax, Sony, Nikon) do not offer the right set of commands to allow for fast contrast AF.
I think it would be possible to design a Nikon in-body lens motor+AF electronics that would be both able to drive the AF optimized for contrast AF and for PD-AF (with lenses that use the internal motor).
[quote name='Brightcolours' timestamp='1285254090' post='3171']
It is just a fact, that lenses and their motors/electronics/software are geared towards responding to commands from the PD-AF systems. They can make "steps" which are geared towards being able to see phase difference as quick as possible. And they can respond to "move x amount" and to "move to there".
Contrast AF works different, it just needs a lens to move relatively slowly until it sees contrast going worse again. Then it knows it reached focus.
To achieve this with the PD AF lenses is difficult, the implementations of how the motor is being commanded is just so very different. That is why with ALL manufacturers, we see comparatively slow AF, we see the lenses take actual small steps towards focus and beyond and back. While the manufacturers with the same image processors achieve contrast AF fast and fine with their compact digitals.
Nikon, Canon, Pentax, Olympus, all show slow AF in contrast AF with PD-AF lenses.
Sony does not offer contrast AF, with live view via the main sensor they chose to only offer MF (A5X0 series).
The Sony NEX series does not AF at all with the Sony PD-AF lenses, even when they are SAM or SSM lenses.
Olympus with micro 4/3rds only offers fast contrast AF with the new micro 4/3rds lenses, the older PD-AF lenses either do not AF at all, or offer a slower contrast AF performance.
It is just that way, Wim... lenses designed to respond to a PD-AF protocol (or in-body motors/AF electronics (Pentax, Sony, Nikon) do not offer the right set of commands to allow for fast contrast AF.
I think it would be possible to design a Nikon in-body lens motor+AF electronics that would be both able to drive the AF optimized for contrast AF and for PD-AF (with lenses that use the internal motor).
[/quote]
Thank you for that extensive explanation, Brightcolours.
I do think however that in the case of Canon the slow C-AF is mainly due to the fact that Canon cameras just aren't optimized to do this type of sensor-based AF yet. If I see how the 85L II focuses f.e., I think it should be very feasible to use the same mechanism for C-AF without a problem, and faster with any other USM lens, provided the camera has a good C-AF system which can operate, ideally, independent from the way the sensor normally works.
Kind regards, Wim
Gear: Canon EOS R with 3 primes and 2 zooms, 4 EF-R adapters, Canon EOS 5 (analog), 9 Canon EF primes, a lone Canon EF zoom, 2 extenders, 2 converters, tubes; Olympus OM-D 1 Mk II & Pen F with 12 primes, 6 zooms, and 3 Metabones EF-MFT adapters ....
[quote name='wim' timestamp='1285256661' post='3174']
Thank you for that extensive explanation, Brightcolours.
I do think however that in the case of Canon the slow C-AF is mainly due to the fact that Canon cameras just aren't optimized to do this type of sensor-based AF yet. If I see how the 85L II focuses f.e., I think it should be very feasible to use the same mechanism for C-AF without a problem, and faster with any other USM lens, provided the camera has a good C-AF system which can operate, ideally, independent from the way the sensor normally works.
Kind regards, Wim
[/quote]
If you look at for instance a G10/11/12... they use exactly the same imaging/computing core, which also manages the contrast AF from the imaging sensor (Digic). So it is not that... Canon has contrast detect AF from the imaging sensor + Digic computer covered well.
[quote name='Brightcolours' timestamp='1285257154' post='3176']
If you look at for instance a G10/11/12... they use exactly the same imaging/computing core, which also manages the contrast AF from the imaging sensor (Digic). So it is not that... Canon has contrast detect AF from the imaging sensor + Digic computer covered well.
[/quote]
Yes, I realize that. I just wonder in how far the APS-C, APS-H, and FF sensors and circuitry are really prepared for this. There are a few Canon "compacts" which use USM, so therefore it should really be possible <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/biggrin.gif' class='bbc_emoticon' alt='  ' />.
Kind regards, Wim
Gear: Canon EOS R with 3 primes and 2 zooms, 4 EF-R adapters, Canon EOS 5 (analog), 9 Canon EF primes, a lone Canon EF zoom, 2 extenders, 2 converters, tubes; Olympus OM-D 1 Mk II & Pen F with 12 primes, 6 zooms, and 3 Metabones EF-MFT adapters ....
[quote name='wim' timestamp='1285257896' post='3177']
Yes, I realize that. I just wonder in how far the APS-C, APS-H, and FF sensors and circuitry are really prepared for this. There are a few Canon "compacts" which use USM, so therefore it should really be possible <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/biggrin.gif' class='bbc_emoticon' alt=' ' />.
Kind regards, Wim
[/quote]
All the sensors now can deliver 30fps... so they should be up to the task. It is not the USM that makes the fast contrast AF possible, but the implementation of motor electronics commands. The lens motor type is not important, really. <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/blink.gif' class='bbc_emoticon' alt=' ' />
So... three things possible:
New mount with contrast detect AF only lenses, old lenses (with mount adapter) offer slower AF.
New lens "models" which offer both the PD-AF command set and the contrast AF command set, old lenses offer slower AF with contrast AF.
PD-AF done on sensor level, no need for contrast AF and old lenses (with mount adapter) offer fast PD-AF still.
[quote name='Brightcolours' timestamp='1285259412' post='3178']
All the sensors now can deliver 30fps... so they should be up to the task. It is not the USM that makes the fast contrast AF possible, but the implementation of motor electronics commands. The lens motor type is not important, really. <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/blink.gif' class='bbc_emoticon' alt=' ' />
So... three things possible:
New mount with contrast detect AF only lenses, old lenses (with mount adapter) offer slower AF.
New lens "models" which offer both the PD-AF command set and the contrast AF command set, old lenses offer slower AF with contrast AF.
PD-AF done on sensor level, no need for contrast AF and old lenses (with mount adapter) offer fast PD-AF still.
[/quote]
I'm in the camp that at least with USM lenses, it shouldn't be the limitation of the lens.
Two things to remember: Compact cameras have smaller sensors, larger DOF, they do not need to focus as precisely as APS-C or FF, which need to be resolved much finer.
Second possibility: CCD versus CMOS, and their implementations.
With compact cameras they may actually only read subsets of the whole sensor for analysis (selected regions, or binned images - since DOF is sufficient)
With CMOS sensors, it seems until recently one had to read each whole image into the processor and analyse of course a whole series - processor and memory demanding. Now, there is the movie mode, reading only samples of the chip - 30fps. Alas, it's resolution limited, so probably not 100% suitable for fast lenses with tiny DOF.
Another issue is finding the initial right focus range. With compacts, due to high DOF, contrast detect has something to work with from the start usually. With many dSLR lenses (e.g. tele), a contrast detect may just see mush at the beginning and going through the whole focus range is much longer, due to the finer resolution needed because of the smaller DOF the lenses have to handle- if the AF knew that it could jump in larger steps, it would go faster of course.
In any case, it seems the difference is not that much nowadays. THe EF-S 60mm USM macro seems to focus quite fast on a 550D - not really that much worse than P&S, once it's in a range where the contrast detect has something to work with.
I think the trick will be to have a little lever with a phase detect system pop-in from the side to give initial fast focus.
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