Moiré: dealing with it.

Really excellent illustration of the problem.

Aliasing issues are the single most troubling technical difficulty for myself.

The only solution I have been able to find is even more of a deteriorating process, but at least it works in many situations. The Caprock 1.0 for the 5D with increased in-camera sharpening or the Caprock 2.0 for the 7D. And that is only for certain wide-ish lenses. Some people even put black diffusion filters on top...

The real difficulty is determining when the Moiré is happening. No practical solutions on that yet...
 
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Thanks, Barry, and you're welcome. Glad I can help.

One other thing I notice is, moire seems to appear much worse on the camera LCD than it actually is in the full resolution footage. When I viewed my "almost acceptable" range, it appeared to be much worse than how it looks at full size.

I'd imagine on a small monitor the same would be true but to a lesser degree.

So it would seem, this is yet another example of having our cake but merely being able to taste it every now and then too as in the case of 1/3" chip cameras with lens adapters that give the coveted shallow depth of field while also degrading the image quality.

If people want the "look" from an inexpensive DSLR, as mentioned, use of a Caprock filter will similarly cause loss of image quality.

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Wow, I had no idea it was that bad....this alters my thinking a little...

Thanks for putting this out there...
 
monday1313 said:
Wow, I had no idea it was that bad....this alters my thinking a little...

Thanks for putting this out there...
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I've shot around 100 hours of 5D footage and never run into shot-ruining moire like this. This is a very rare example.
 
Drew Ott said:
If you shoot curtains as a profession then, by all means, the 5D is not for you.
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The type of patterns that would cause moire are not rare. They can easily be found in real life, on certain clothings for example. So unless you're doing porn then you stand a pretty good chance of running into this situation at some point and have it ruin your shot. Knowing about it before hand lets you avoid it by changing the choice of wardrobe for example. Nobody is singling out the 5D; it's just one of those undeniable weakness that if you're not aware of, will ruin your shot (just like rolling shutters that every EX1 owner will swear that they've never encounter before).
 
@Chris

Hi when you shot that did you put your camera in nuetral? I mean did you turn the sharpening all the way down, etc etc.

thanks!
 
Yes, the sharpening was down. I doubt it would have made all that much of a difference either way, but I'm going to check it again when I get a chance with various degrees of sharpening.

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in looking at the test i would think this is more a thing with your lens...it must not be as sharp at certain focal distances and then cant resolve the date making it moire like that. wouldnt be a problem with primes or if you stick to the normal focal lengths on your zoom lens.
 
No, it has to do with the way the patterned detail lines up on the sensor. At certain distances it'll fall between the pixels, and at other distances it'll fall directly on the pixels. Chris demonstrated the effect exactly, and there's absolutely nothing wrong with his camera, or lens. ANY DSLR will behave exactly the same way, and that's one thing that makes this moire thing so frustrating -- sometimes it shows up, sometimes it doesn't.
 
monday1313 said:
I mean did you turn the sharpening all the way down, etc etc.
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As Barry has shown with 7D the sharpening happens post the downscale and prior to the encoding so it has no effect on when moire occurs. Probably all current HDSLRs including 5DmkII does the same.

Barry_Green said:
Sharpness makes no difference. It exaggerates the contrast so that you can see black and white as black and white instead of shades of gray, but all the same aliasing is still there.

Here's the 7D with sharpness set to maximum, and with it set to minimum.

7D-720-Min-Max-Trumpets.jpg
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The sharpening setting probably doesn't make a difference, but the contrast setting DOES make a difference. This I have seen in my own work.
 
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