Noisy EX3 shots

[Doug Jensen]

There are ways of recording 35mbps 422 with external recorders. But that was not my point anyway. My point is that the 35Mpbs bit rate is NOT what it is important for better picture quality -- what is important is the 422 color resolution. If the 50Mpbs comes along with it, fine, but that is not the important part of the codec.

Why don't you do this: Get a NanoFlash and record XDCAM 4:2:0 at 35Mpbs and 100 Mbps and see if you see an ounce of difference in noise between them. If not, then clearly the bit rate is not the important ingredient of the codec's recipe. I know, because I have actually done the test.

Like I said, it is the 422 vs. 420 that is important, and if that is what you meant to say in your first post then you should have chosen your words more carefully to be more accurate in what you were trying to say.

If you don't understand that, then I give up. In fact, I give up anyway because I have better things to do that argue about dumb stuff like this. You are more than welcome to have the last word and refute everything I have said. Knock yourself out.

[Jacques Mersereau]

Easy Brothers :-D

Unless I have this wrong,

4:2:0 = noisy blacks at whatever bit rate (because of the hideous noise in the blue channel?)

4:2:2 at 50mbps (or higher) make the blacks look much better - probably because the blue channel is much less noisy.

EX3 is a great camera for what it does, but there are things that are not quite up to snuff.
The sensor is noisy (when compared to say the F3)
Many times I have noticed that there must be IR contamination, because on certain fabrics- say black pants, they look brown/maroon.
(and no, I don't want to have to use an IR filter and lose a stop or two)
The zoom on the stock lens does not do a super slow crawl without hiccups when using external zoom controller.

As always, YMMV.

[Doug Jensen]

Jacques, I am in complete agreement on everything in your post.

[Alister Chapman]

Bit rate does effect noise with high compression codecs as the lower the bit rate the more quantisation noise and macro blocking you get. With the same codec and higher bit rates there is less compression noise, typically seen as mosquito noise. Macro blocking and quantisation noise often manifests itself as banding across near even surfaces or the sky etc.
The 422 recordings of the PMW-200 need more data than the 420 recordings, so much of the data difference between 35Mb/s and 50Mb/s goes purely on the extra data, but finer sampling of the chroma will result in less coarse noise which tends to be less noticeable or objectionable than coarser noise.

If the bit rate wasn't important then we would all be shooting 25Mb/s 422, but the bit rate does matter with a higher bit rate generally resulting in fewer artefacts including quantisation noise.

I did many tests with the Convergent Design NanoFlash when that came out comparing different bit rates and there was a useful noise improvement when going from 50Mb/s to 100Mb/s. The viewer would may not always see this difference, but if you want to grade your material then the reduced quantisation noise means less likelihood of seeing any banding in your footage and the ability to grade the material with less degradation. Compression noise is a bigger cause of banding in footage than "only" 8 bit encoding.

[Garrett Low]

Alister, thanks for that explanation. I have experienced exactly what you have said in your post. which is why my usual recordings on my EX3 are done at 100 Mb/s on my nanoFlash when using Long-GOP (of course I also record to the internal cards). There is a notice a difference when comparing the internal 35 Mb/s to the nanoFlash recordings at 100 Mb/s. I can't understand how people don't see it. It might have something to do with the circuitry of the nanoFlash vs. the EX3's but there is a difference.

[Jacques Mersereau]

Friends don't let friends try to CC 35mbps.