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Old November 5th 14, 11:15 AM posted to rec.photo.digital.slr-systems
Floyd L. Davidson
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Posts: 5,138
Default AA filter vs. OLPF filter

nospam wrote:
In article , Floyd L. Davidson
wrote:

I'm confused by something. Many new cameras today advertise no
anti-aliasing filter (AA) or optical low-pass filter (OLPF). But are
they the same thing?? I came across one article that seems to say no,
saying (IIRC) the Nikon D810 has neither. However, I wonder if some
articles that say a certain camera doesn't have one or the other are
maybe using the terms interchangeably. Is it possible if a camera does
not have an AA filter it still has the OLPF, or vice versa? What's the
scoop?

two names for the same thing.

note that the d800 had an anti-alias filter for one direction and what
nikon called an un-alias filter so that the optical path was the same,
letting nikon produce the d800 and d800e without major differences.

make that the d800e with the un-alias filter. the d800 had an
anti-alias filter for both directions.


"Un-alias" filter?


yes. in the d800e, the second filter reverses the effect of the
anti-alias filter, thus its name.


It's name is not, and never has been, "un-alias" anything.

Nothing in any of your cites suggests that is correct
terminology, and it isn't. It does suggest a total lack
of understanding about what the filter does. It is an
*anti* aliasing filter because it helps to stop
aliasing. There is no filter that *un*-aliases
anything.

--
Floyd L. Davidson http://www.apaflo.com/
Ukpeagvik (Barrow, Alaska)