C100: "Sizzle" Present In Shots of Balast Or Fine Rock Patterns

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deserttortuga

New member
This is a bit difficult to describe but here goes:

Part of my repertoire is filming railroads. Railroad right-of-ways have deep ballast to keep the track in place. The ballast is composed of rocks the size of walnuts to small apples. When I film at track side, after grading, the ballast looks like it's "sizzling," as if electrical pulses are running through the right-of-way. It's very distracting. Sometimes it is more prevalent in some shots than others. This not only shows up in the railroad shots, but I was out last weekend shooting a creek where the same fine pattern was present on one side of the bank, and had the same effect. Here are the particulars.

1. Filmed on a tripod.
2. Lens was Canon 24-105, with stabilizer off.
3. Focal length typically wide between 24 to 35mm.
4. Canon LogC at ISO 850, Sharpness turned off.
5. Output to a Ninja recorder, ProRes HQ 4:2:2.
6. LUT converted to Wide Dynamic with Colorista's LUT Buddy, graded in Premier Pro CS 6 with color correction from Colorista II.
7. Sent to Encore for conversion to BluRay.

I've tried using Denoiser II, and that didn't seem to work. The problem happens even in WDR, sharpness turned off. The problem is most prevalent with the wider focal lengths of the Canon 24-105. I've had two of these lenses, and the problem persists.

I'm not a professional, so I don't have a professional monitor for which to grade. And frankly, the problem may be the Sony BluRay or the Samsung LED that I'm playing it on.

Sometimes I suspect the problem might be related to the audio, which is completely strange, because when there is a rise in the background dB, the "sizzle shock wave" corresponds to the increase.

Any ideas?

Thanks.
 
Could you post a frame or preferably a clip for us to see? It sounds like moire or aliasing which has to do with fine lines and patterns. Is there camera movement in your shots?
 
deserttortuga said:
7. Sent to Encore for conversion to BluRay.
Click to expand...

What does this mean? Conversion from what, to what? IOW, what resolution and frame rate did you capture, and what resolution and frame rate are you trying to use with blu-ray?

I'm asking because Encore itself is somewhat notorious as being a bad way to convert anything. If you have access to AME, you'll generally get much better conversions. That said, you can setup Encore to use AME for conversions.

More details please.
 
TSDavis said:
Could you post a frame or preferably a clip for us to see? It sounds like moire or aliasing which has to do with fine lines and patterns. Is there camera movement in your shots?
Click to expand...

I'll try to isolate the footage to post on the board. It would have to be H.264 and I'm not sure how this would get done on the this board.

It does sound like moire or aliasing, but there is no movement in the frame, which makes it puzzling. I also thought ProRes HQ at 4:2:2 at 220Mb solved most of those issues.

The C100 camera was returned to Canon about a year ago because of a couple hot-pixels. They repaired it and returned it. But I had noticed the problem before.
 
Bruce Watson said:
What does this mean? Conversion from what, to what? IOW, what resolution and frame rate did you capture, and what resolution and frame rate are you trying to use with blu-ray?

I'm asking because Encore itself is somewhat notorious as being a bad way to convert anything. If you have access to AME, you'll generally get much better conversions. That said, you can setup Encore to use AME for conversions.

More details please.
Click to expand...

The C100 frame rate was 24P at 1/48. The Ninja is recording at 23.98 3:2 drop frame at ProRes HQ 4:2:2 at 220Mbps. The Ninja *.MOV files are transported directly to CS 6, edited with the proper LUT and graded. After this is done, it is transcoded in Encore with the following settings: NTSC H.264, 1920x1280, 24P at 40.0Mbps.

Whether I denoise it, or sharpen it, or use unsharpen mask, the results are, to my poor eyes, about the same. The shoot is in natural light, of course, with about average light to fading light. The creek shot was during an overcast sky, light rain, surrounded by dense green. My memory is a bit fuzzy, but I believe an ND setting was necessary. (BTW, I do a ABB before every shoot, and if time permits, a WB).

I'm not familiar with AME, but since I'm considering moving to Resolve, I will have to check it out. How does on get access to AME?

Thanks
 
AME stands for Adobe Media Encoder. If you have; premiere, after effects, encore, etc, you should have AME installed on your machine already. If by chance you are missing that application look for your install discs or dmgs
 
Question: Were you close enough that the ground you were standing on was vibrating as the train passed?

I used to have a railroad client and shot a lot of freight and I have a theory. It depends on how far you were from the tracks. I bet that either the ballast was jiggling slightly and/or the vibrations were coming up from the ground, through your tripod to the camera and this cause a slight movement, similar to moire, which you term sizzling. I remember the ground shaking. So in effect, I think it is a type of moire.

Also, why 24? Things tend to strobe more at 24 especially horizontal items like a train crossing frame. I'd do 30 plus I'd experiment with higher shutter speeds. I know it's a pain because you can wait hours for a freight but experimentation is the way to go. Slate each one. I'd bet 30P at a higher shutter would capture it.

I've had a "sizzling" artifact when shooting trees and the wind picked up and you saw it in the leaves. So I bet it was a slight movemet of the little ballast rocks. Also, watch out for hoboes.
 
deserttortuga said:
After this is done, it is transcoded in Encore...
Click to expand...

First thing I would do is use some other program (like AME, Adobe Media Encoder) to do your transcode. Encore itself sucks at this. Search for it, you'll find all sorts of sad stories about Encore's transcoding performance, or lack thereof.

Once you've done the transcode, import that into Encore for Encore to use to build your blu-ray. Don't let Encore re-transcode anything.

This alone might solve your problem.
 
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