Sony A100 to A700

[A complimentary Cc of this posting was sent to
frederick
<lost.RemoveThis@sea.com>], who wrote in article <1212482281.344227@ftpsrv1>:
> > Now we know that it is not a myph. Visual comparison of Foveon images
> > and Bayer images gives an advantage of about 2x in pixel count.
> > (Myself, I was expecting something about 1.5x...)

> I don't know what you are arguing about.
> 4.69 x 2 = <10mp

I don't know what you are arguing about. As dpreview images show,
there are some situations where 4.69x3 sensor gives better "visual
impression of resolution" (sorry, can't find a better term) than 10mp
Bayer sensor. *This* is what surprised me.

> IIRC DPreview already said the ("3.4mp x 3") SD10 was similar to 6mp
> dslrs in resolution - so nothing new here.

Can't agree here - I do not remember anything about sd10 which would
suggest getting close a factor of to 2x. 6/3.4 = 1.76 which is
similar to what one would expect from inspection of images shot with
Bayer sensors (see threads about "dead pixels" in relation to MTF).

> "So what we'd really like to see is a sensor that combines the Foveon's
> per pixel resolution with the output size of a modern DSLR.

Do not think so. What "we'd really like to see" is a
separation-in-silicon sensor with pixel count about 40MP per square
inch, and capacitance/area and read noise similar to current Canon
sensors. *This* would start to utilize the potential of the best
lenses...

Hope this helps,
Ilya
 >> Stay informed about: Sony A100 to A700 

In article <g38osm$23l3$1@agate.berkeley.edu>, Ilya Zakharevich
<nospam-abuse.TakeThisOut@ilyaz.org> wrote:

> > > Now we know that it is not a myph. Visual comparison of Foveon images
> > > and Bayer images gives an advantage of about 2x in pixel count.
> > > (Myself, I was expecting something about 1.5x...)
>
> > I don't know what you are arguing about.
> > 4.69 x 2 = <10mp
>
> I don't know what you are arguing about. As dpreview images show,
> there are some situations where 4.69x3 sensor gives better "visual
> impression of resolution" (sorry, can't find a better term) than 10mp
> Bayer sensor. *This* is what surprised me.

the 'visual impression' is nothing more than alias artifacts and a lot
of sharpening in raw processing. some people like the look and others
don't. in any event, it's not true resolution.
 >> Stay informed about: Sony A100 to A700 

[A complimentary Cc of this posting was sent to
nospam
<nospam RemoveThis @nospam.invalid>], who wrote in article <170620081321232208%nospam@nospam.invalid>:
> > > I don't know what you are arguing about.
> > > 4.69 x 2 = <10mp

> > I don't know what you are arguing about. As dpreview images show,
> > there are some situations where 4.69x3 sensor gives better "visual
> > impression of resolution" (sorry, can't find a better term) than 10mp
> > Bayer sensor. *This* is what surprised me.

> the 'visual impression' is nothing more than alias artifacts and a lot
> of sharpening in raw processing.

??? There is no sharpening involved. Moreover, as resolution chart
shots show, there is no significant aliasing either.

> some people like the look and others don't. in any event, it's not
> true resolution.

Can't agree less. "True" resolution is what I can or can't see.

Any other "objective" metrics are just, in some sense, a window
dressing: trying to capture this - elusive - "visual impression of
resolution" via some "scientific metric". People who look at images of
resolution chart with Bayer sensors understand quickly how these data
correlate with "visual sharpness" of images.

It turns out that the (B&W) resolution charts do not fully correlate
with "visual impression of resolution" if one compares them between x3
and Bayer sensors. (AFAIU, the "color resolution charts" of dpreview
is an attempt to introduce an objective metric which reflects better
the way our visual system works.)

Yours,
Ilya
 >> Stay informed about: Sony A100 to A700 

In article <g38t8a$24uo$1@agate.berkeley.edu>, Ilya Zakharevich
<nospam-abuse.RemoveThis@ilyaz.org> wrote:

> > > I don't know what you are arguing about. As dpreview images show,
> > > there are some situations where 4.69x3 sensor gives better "visual
> > > impression of resolution" (sorry, can't find a better term) than 10mp
> > > Bayer sensor. *This* is what surprised me.
>
> > the 'visual impression' is nothing more than alias artifacts and a lot
> > of sharpening in raw processing.
>
> ??? There is no sharpening involved.

absolutely there is. there's sharpening of the bottom layer (sometimes
referred to as the red layer) due to diffusion in the chip, plus a
heavy dose of sharpening in the raw processor itself. sigma photo pro,
when set to '0' actually applies quite a bit of unsharp mask.

> Moreover, as resolution chart
> shots show, there is no significant aliasing either.

quite the opposite. there's a lot of very visible aliasing. just look
at dpreview's resolution charts. it's also noticeable in many images.

> > some people like the look and others don't. in any event, it's not
> > true resolution.
>
> Can't agree less. "True" resolution is what I can or can't see.

people see what they want to see. true resolution is what can be
objectively measured.

> Any other "objective" metrics are just, in some sense, a window
> dressing: trying to capture this - elusive - "visual impression of
> resolution" via some "scientific metric". People who look at images of
> resolution chart with Bayer sensors understand quickly how these data
> correlate with "visual sharpness" of images.
>
> It turns out that the (B&W) resolution charts do not fully correlate
> with "visual impression of resolution" if one compares them between x3
> and Bayer sensors. (AFAIU, the "color resolution charts" of dpreview
> is an attempt to introduce an objective metric which reflects better
> the way our visual system works.)

nonsense. b/w resolution charts measure luminance resolution which is
what matters to human vision. colour resolution charts exploit a known
weakness of bayer and make foveon look better than it really is (which
is why foveon fans insist on colour res charts).

colour res charts have little to do with real world scenes or human
vision. simple test - compare two of the same resolution charts, one
b/w and one in colour (ideally complementary colours with constant
luminance) and note the difference. you'll be able to resolve the b/w
chart a whole lot better.
 >> Stay informed about: Sony A100 to A700 

[A complimentary Cc of this posting was sent to
Ron and Gail Smith
<ron_smith RemoveThis @clear.net.nz>], who wrote in article <4849fd47$1@clear.net.nz>:
> Hey, a lot of good info'
> But still undecided

I forgot another point where people report that a100 is "just a toy",
and a700 flies: flash exposure. There is something very fishy with
the algorithm of a100 (*very* unreliable). a700 is reported to
perform very reasonably.

Hope this helps,
Ilya
 >> Stay informed about: Sony A100 to A700 

Great and Thanks

Ron
"Ilya Zakharevich" <nospam-abuse DeleteThis @ilyaz.org> wrote in message
news:200806171750.m5HHo26U021548@powdermilk.math.berkeley.edu...
> [A complimentary Cc of this posting was sent to
> Ron and Gail Smith
> <ron_smith DeleteThis @clear.net.nz>], who wrote in article <4849fd47$1@clear.net.nz>:
>> Hey, a lot of good info'
>> But still undecided
>
> I forgot another point where people report that a100 is "just a toy",
> and a700 flies: flash exposure. There is something very fishy with
> the algorithm of a100 (*very* unreliable). a700 is reported to
> perform very reasonably.
>
> Hope this helps,
> Ilya
>
 >> Stay informed about: Sony A100 to A700 

nospam <nospam RemoveThis @nospam.invalid> wrote in news:170620081406183919%
nospam RemoveThis @nospam.invalid:

> nonsense. b/w resolution charts measure luminance resolution which is
> what matters to human vision. colour resolution charts exploit a known
> weakness of bayer and make foveon look better than it really is (which
> is why foveon fans insist on colour res charts).

Blue vs green, which is Foveon's weakest area, is omitted.

--
John Sheehy
 >> Stay informed about: Sony A100 to A700 

Ilya Zakharevich <nospam-abuse.DeleteThis@ilyaz.org> wrote in news:g38t8a$24uo$1
@agate.berkeley.edu:

> Can't agree less. "True" resolution is what I can or can't see.

It doesn't matter if it has any direct relationship to what was suppposed
to be recorded?

Does a dull print viewed through shattered glass have more resolution?

--
John Sheehy
 >> Stay informed about: Sony A100 to A700 

Fred McKenzie wrote:

> I believe the same is true of other APC-sensor DSLRs on the market.
> Most are on a par with the Sony. No one is so much better that a change
> from any other is justified. (Contrary to opinions expressed by certain
> other-brand bigots!)

Depends on the lens availability. Apparently the Nikon 18-200 VR lens
did cause changes from other brands, as did the Canon 10-22 wide angle lens.

A lot of people look at the big picture, not just at the body but at
what lenses are available and at what price.
 >> Stay informed about: Sony A100 to A700