Moire Issues

[David Fairbanks]

Has anyone heard if Red has mentioned moire. It's been a issue on electronic cameras since day one as far as I know. I'm sure they will have the absolute best processing to eliminate it.

Having shot with digital stills for years, I know that the higher the resolution of the sensor, the more susceptible you are to moire in fabrics like suit jackets and the like. Smaller images from large sensors can give you moire when the actual full size image doesn't have a problem. It's even worse when the small image doesn't show anything and the full size image is covered in it.

In stills the best way to elevate it is to change focal length slightly and reshoot the shot. This wont be practical in most situations with Red.

[Brook Willard]

Hmm... perhaps there will be an optical low-pass filter over the sensor? I suppose there would be downsides...

[David Fairbanks]

Low pass... I don't see that would do anything. But I also haven't messed with low pass filters (or high pass for that matter).

[Finner]

I don't understand moire. Is that a different word for alising?

[David Fairbanks]

Moire is interference patterns.
The texture in cloth for instance will render in odd patterns when it is captured by a patterened sensor.

[Brook Willard]

An OLPF effectively blurs the image just a TINY little bit to avoid moiré. Again, it's good and bad.

[David Fairbanks]

If it's over the sensor, we wouldn't have the option of removing it. But if it's not a noticable amount of softening, it probably wouldn't matter.

Surely my D2X doesn't have it, it loves to moire.

[Brook Willard]

It's about 1-2 pixels of blur generally... I guess we'll find out.

[Anders Holck]

Every Bayer based sensor should have a OLPF that matches the sensors resolution.
Current pro DSLR's seem to have a filter that is tuned for a sharper image and will still show a little moiré in worst case situations.
The RED camera will have one as well. I believe some of the first shots previewed was without any filter, but the recent ones were with it fitted.

[Brook Willard]

Was that ever mentioned? I don't recall reading that anywhere.