Is the AA filter on the endangered list too?

In rec.photo.digital RichA wrote:

Seems like lighter and lighter AA filters are appearing in certain
cameras. The Leica has none. Could it be that this second-last
barrier to resolution (the Bayer filter being the last) isn't long for
the world?

Leica's absence of an A filter isn't new. Where are the lighter and
lighter ones appearing? And given that every camera maker is producing
cameras with larger and larger pixel counts at least every other year,
why is the AA filter a barrier to resolution?

--
Chris Malcolm

RichA wrote in news:af3ea6dd-b7e2-430e-bd14-
:

On Mar 27, 5:38*am, Chris Malcolm wrote:

And given that every camera maker is producing
cameras with larger and larger pixel counts at least every other year,
why is the AA filter a barrier to resolution?

When 24 megapixels with, is like 16 megapixels without.

No. 24 "with" has more resolution, but lower *contrast* near the nyquist.
16 "without" is more aliased. Apples and oranges; no simple monolithic
metric.

"John Sheehy" wrote:
RichA wrote:

On Mar 27, 5:38 am, Chris Malcolm wrote:

And given that every camera maker is producing
cameras with larger and larger pixel counts at least every other year,
why is the AA filter a barrier to resolution?

When 24 megapixels with, is like 16 megapixels without.

No. 24 "with" has more resolution, but lower *contrast* near the nyquist.
16 "without" is more aliased. Apples and oranges; no simple monolithic
metric.

If you actually look at some test charts, and use the (rather reasonable)
metric that "to resolve" must mean _to resolve accurately_, then what you
see is that 16MP without an AA filter has less resolution than 16MP with an
AA filter. (For the obvious reason that aliasing artifacts obscure actual
detail.)

--
David J. Littleboy
Tokyo, Japan