August 21, 2013

Issues with Moire on the Blackmagic Cinema Camera? Mosaic Engineering Has a Solution

The Blackmagic Cinema Camera is even more of a bargain now that BM has reduced the price by $1,000. 10-bit ProRes/DNxHD and RAW recording for just $2K is quite a deal all things considered, but there is still the nagging issue of occasional moire since the BMCC lacks an Optical Low Pass Filter/Anti-Aliasing Filter, or OLPF/AA filter. A company well-known for producing those exact filters for Canon DSLRs, Mosaic Engineering, is making progress on a special OLPF filter designed specifically for the Blackmagic Cinema Camera.

Thanks to Kraig for the heads up on this one. You've got to either download it or watch on a full 1080 screen, as there is some aliasing inherent in downscaling the image to fit your screen:

Here is their Vimeo description:

This is a brief demonstration of our initial tests of the first revision of our new optical anti-aliasing filter for the Blackmagic Cinema Camera (mosaicengineering.com).

This source material for this video was recorded in the BMCC's ProRes 4:2:2 "video" mode, and as such the footage is a little noisy. We'll be rendering this again shortly with "film" mode source material, which we believe should improve the noise and dynamic range.

Because this initial anti-aliasing filter is a spatial low-pass filter (or what's sometimes called an Optical Low-Pass Filter or OLPF), a small amount of high-resolution image detail is attenuated by it.*** Therefore, in the middle segment of the posted video, we've applied a small amount of postproduction sharpening, to try to match the subjective sharpness of the original unfiltered material. For reference and comparison, we've also included a sample of the original, unsharpened, AA-filtered source material.

It's unclear when we might actually see this filter for sale, but the results of this first version are definitely promising. I honestly didn't notice the aliasing/moire when I was using the BMCC, but it is there in certain instances. This filter should remove the most distracting rainbow patterns from the image, and bring the focus back on your subject where it belongs. There is always a trade-off between removing moire and keeping enough fine detail, but thankfully the very sharp image from the BMCC should lend itself well to using a filter like this.

BMCC users, what do you think? If it ends up costing somewhere in the $300-$400 range, will you add this to your kit?

Link: Mosaic Engineering

Your Comment

19 Comments

It may be worth considering that this filter might affect the reliability of witness marks on cinema lenses because it changes the path of the light. I'm pretty sure that's the case with the one for the 5Dmk2. Does anyone know differently?

August 21, 2013

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David

I wouldn't pay more than $50 for this filter as I rarely have such issues with my BMCC. If you avoid using super sharp modern glass, you'll find few such issues with the BMCC. In any case, I find that carefully filtering out various noise channels via Neatvideo eliminates the rare bit of moire that is bothersome.

August 21, 2013

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darnell

Moire almost killed a key shot of mine with the BMCC: http://i.imgur.com/U9htb0h.jpg (from http://vimeo.com/shivimpanim/in-the-hands-of-heaven)

This image is after all the compositing and grading etc. which hid it better, but when I saw the original it was seriously distracting and worried me.

A solution is definitely welcome, though I wouldn't rely on it... much better to solve it from an art/wardrobe perspective if possible. I shouldn't have allowed the vest with the small lines.

August 22, 2013

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Of the three videos I've seen of distracting moire on the BMCC, all were of clothes, and not necessarily fine patterns: one was of a solid-coloured hi-tech synthetic mountaineering jacket.

August 22, 2013

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Taylor

Interesting... this vest was also synthetic I think... it did have fine lines, but maybe that was only part of the problem... could different material types actually play a part in it besides size of design patterns?? That would be really useful info and news to me...

Though the opening shot also has a bit of it going on too with organic wood beams- not as bad, but see: http://i.imgur.com/Dgrtr1M.jpg

August 22, 2013

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David, what you're seeing is not moire, it's the reflection of the bracelets blinking on the fabric. Moire is typically caused by interlacing in NTSC or when compressed to a small video format. If you had moire problems, then you would see it on the basket or other "lines/patterns" in the video. Look back at the footage and how the "moire" compares to the lights.

August 22, 2013

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John

Hey John, thanks for watching the video and giving the issue some thought. Unfortunately, it is in fact an aliasing+moire artifact. Here is a better-chosen frame to illustrate the problem: http://i.imgur.com/BfSJq4L.jpg

Notice the lines if not sold on the rainbow (though both are aliasing issues... I wish the LED's had that kind of throw under the hot lights!)

Not saying the BMCC is better or worse than any other camera in this area, but it does have the problem at times and a device like the one mentioned in this article would be helpful, for sure.

August 22, 2013

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My personal opinion is moire only seems to bother we camera guys. I see it all the time on tv or whatever, and have yet to witness anyone complain about it. It's like ever since getting into video production I've become aware of the technical aspect of movies and had to sort of retrain myself to get lost in the story.

August 22, 2013

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Robert

Yep! Shame we're all camera guys ;)

August 22, 2013

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Kraig.

only as long as the client doesn't complain ;)

August 22, 2013

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hansd

I have yet to see anything significant in the footage I've shot, but it's nice to know there's options. Not too concerned about it, though.

August 22, 2013

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I see aliasing all the time on Black Magic, its ruined a few shots. I'll gladly take it for $400-500.

August 22, 2013

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ryan

Looking at the video I think it definitely makes a difference. In reality an OLPF filter is something that is generally expected as a necessity for video. Only recently have manufacturers been making the choice to exclude them and even now those manufacturers are a minority. Some manufacturers even go as far as to push the boundaries of the OLPF and make it a great feature. Take for instance RED making their OLPF an IR filter as well.

The sharpness of the BMCC is excellent and I think the video shows that in can be nearly all brought back. I think it will be interesting to see how this develops for sure but looking at the rainbow patterns on the bricks, I definitely expect to be getting one of these when it is released. I also would be looking forward to seeing how it will look with the upcoming firmware update containing the new debayering algorithm.

August 23, 2013

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99% of audience don't care about things like moire and anti-aliasing. if a picture has a great story, hardly anyone cares. you are being tricked by marketers in the never ending hamster wheel upgrade cycle.

August 23, 2013

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ishoot720p

ONE HUNDRED percent correct. Not even distributors care when you show them to sell.

August 25, 2013

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B S Kumar

I shot short film recently where we cut some footage from 7D and one particular shirt had mire and aliasing in every shot on 7D no matter how I shot it where BMCC had none.

BMCC in my opinion has no major issue with it.

August 26, 2013

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Darko

If you are shooting a 1 point perspective steadishot tracking shot with geometric lines, you WILL notice crooked aliasing with most cameras. This filter fixes alot of it.

October 26, 2013

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ThaiMan

its definitely needed for the pocket cam. and welcome.

January 2, 2014

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Gearie Bowman

Any news on this filter and when it'll be available? It's not aaabsolutely needed in my case but I'd like to have it for certain occasions.

January 22, 2014

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