From: David J Taylor on
"Alfred Molon" <alfred_molon(a)yahoo.com> wrote in message
news:MPG.2665d090fe2ae3a398c30a(a)news.supernews.com...
[]
> The fixed R&D cost is spread over a large number of items, but the
> manufacturing cost is the same and only shrinks a little bit with
> increasing volumes.
>
> The advantage of in-camera stabilisation is that it's available with all
> lenses, also with very old ones. No need to replace all lenses with
> stabilised ones.
>
> In any case, there is nothing which prevents Nikon or Canon to add IS in
> their bodies. They probably would be able to do so, if they wanted. But
> they perhaps it would get more tough to sell IS lenses to people who
> don't have them yet.
> --
>
> Alfred Molon

... and the disadvantages are that the image in the viewfinder, and on the
exposure and focus sensors aren't stabilised. It seems to me that Nikon
and Canon want to make the best image quality and stabilisation system
available, by using in-lens IS. Of course, better quality will cost more,
but in the case of IS/VR lenses, not a lot more. And likely those newer
lenses will produce better images than the older ones....

David

From: Bruce on
On Tue, 25 May 2010 13:10:33 +0200, Alfred Molon
<alfred_molon(a)yahoo.com> wrote:

>In article <5kjkv51udne8hg9ggllarporrnnb6p2hm7(a)4ax.com>, Bruce says...
>> I wonder why Sony abandoned the in-camera anti-shake of the Alpha
>> system, instead using an in-lens anti-shake system for NEX?
>
>Obviously not enough space in that tiny body for an in-camera anti-shake
>system. Seems like Sony cut the corners too much here.


Or perhaps Sony finally realised that their in-camera system doesn't
work at all well.

From: Bruce on
On Tue, 25 May 2010 13:48:53 +0100, "David J Taylor"
<david-taylor(a)blueyonder.co.uk.invalid> wrote:
>
>It seems to me that Nikon
>and Canon want to make the best image quality and stabilisation system
>available, by using in-lens IS. Of course, better quality will cost more,
>but in the case of IS/VR lenses, not a lot more. And likely those newer
>lenses will produce better images than the older ones....


When IS lenses were first introduced, soon to be followed by VR, there
was great scepticism, particularly among those who tested lenses, that
they would be optically sound.

The reasoning was that one of the most important factors in getting
the best out of a lens design is that the optical centres of all the
elements must coincide along the optical axis of the lens. This is a
non-trivial issue because manual centering can be time consuming and
therefore expensive.

So the logic was that an optical anti-shake system (IS or VR) must
result in inferior lens performance because it introduced a deliberate
decentering of the optical axis.

In practice, however, this was not seen to the case, and IS and VR
lenses produce sensibly similar optical quality to their non-IS and
non-VR predecessors. But it did perhaps lead some manufacturers to
prefer in-body anti-shake systems to in-lens systems (or was it really
because Canon and Nikon had the patents sewn up?).

Of course, experience has shown that in-lens systems are much more
capable, both in terms of the significantly slower shutter speeds that
they allow, and in their much greater consistency and reliability from
one shot to another.

For that reason, it is highly amusing to watch those who were formerly
such passionate advocates of in-body systems (because that is all
their chosen system offered) admitting that they were wrong, and that
their previous postings asserting superiority of in-body systems were
actually a pack of lies. ;-)

From: Alfred Molon on
In article <htgh07$jn5$1(a)news.eternal-september.org>, David J Taylor
says...
> .. and the disadvantages are that the image in the viewfinder, and on the
> exposure and focus sensors aren't stabilised.

At least the exposure sensor does not need stabilised images.

I would also guess that also the focus sensor does not, otherwise the AF
would fail when the subject is moving, and cameras seem to be able to
focus on moving subjects.
--

Alfred Molon
------------------------------
Olympus E-series DSLRs and micro 4/3 forum at
http://tech.groups.yahoo.com/group/MyOlympus/
http://myolympus.org/ photo sharing site
From: David J Taylor on
> At least the exposure sensor does not need stabilised images.

Spot metering?

> I would also guess that also the focus sensor does not, otherwise the AF
> would fail when the subject is moving, and cameras seem to be able to
> focus on moving subjects.
> --
>
> Alfred Molon

Spot focus?

David