Re: Sony A100 to A700
- From: Chris Malcolm <cam@xxxxxxxxxxxxxxxxx>
- Date: 1 Jun 2008 08:08:20 GMT
Alfred Molon <alfred_molon@xxxxxxxxx> wrote:
In article <6a9v4rF36336nU1@xxxxxxxxxxxxxxxxxx>, Chris Malcolm says...
The second point is that it is easier and cheaper to design high
resolution lenses if you can get the back of the lens closer to the
sensor than the mirror allows. The only reason we still need the
mirror is to get the optical viewfinder, and the only reason we need
the optical viewfinder is because EVF isn't yet as good as a good
optical viewfinder. But like sensor resolution, that too is simply a
matter of waiting for the technology to get there at an affordable
price. Just as with the sensor resolution improvement, there's no
inherent physical barrier to making EVFs as good as optical
viewfinders, it's just a case of waiting for the well-established
technological development bandwagon to to get there. The only question
is how long we'll have to wait. We need higher resolution small
internal LCDs, and faster processors capable of translating the larger
amount of sensor "pixels" into the larger display at a fast enough
speed.
I'm being told that to have a fast phase detection focusing system
(typical of DSLRs) you need a mirror. Without mirror, as people here
say, you can only have a contrast detection AF.
Interesting point. If the extra speed of phase detection is simply due
to its knowing in which direction to move to improve the focus, then
there are a number of smart things you could do to contrast detection
to improve its speed which at the moment nobody has bothered to do.
Then there's the point that the mirror doesn't have to be an angled
plane. It could be a lot of slats like a venetian blind. Nasty slat
alignment problems, but that wouldn't matter for the purposes of a
phase detection focusing system.
In other words while you do need a DSLR-type mirror for fast focus
with today's technology, I'm not convinced clever engineers won't be
able to think up another way of getting fast focus.
--
Chris Malcolm cam@xxxxxxxxxxxxxxxxxxxx DoD #205
IPAB, Informatics, JCMB, King's Buildings, Edinburgh, EH9 3JZ, UK
[http://www.dai.ed.ac.uk/homes/cam/]
.
- Follow-Ups:
- Re: Sony A100 to A700
- From: David J Taylor
- Re: Sony A100 to A700
- Prev by Date: Re: Image Storage Device Recommendations
- Next by Date: Re: Image Storage Device Recommendations
- Previous by thread: Re: Sony A100 to A700
- Next by thread: Re: Sony A100 to A700
- Index(es):
Relevant Pages
|
Loading
