AF with Atomos Samurai test screen grabs

Just my random thoughts on this test... FWIW ....and I did my own comparison tests when I got my Samurai some time ago.

My tests were done with Default Camera Settings to eliminate variables and discussion about the "variables". (Fixed Control as baseline)

Transcoding one of the codecs in this test adds a variable!

The samples above are screen grabs..not frame grabs. I suggest that frame grabs are closer to original than screen grabs so view with caution especially considering the "blow up" factor. eg. how is the scaling being done to the original footage?

I have never seen banding on my AF102 ....(apart from the time I was setting up a shot with a hot spot in the BG similar to the test with the mannequin . Banding went away when I got control of the exposures thru lighting control).

I have never recorded any banding issues would be another way of saying this ...but my point is...why shoot a test of a problem that does not need to exist and try and see if the problem is "improved" in the comparison?

Well, the problem does exist, and I would say, why not shoot a test at a higher quality capture to see if it's improved? The answer is yes, it was improved, but not that much. There are learning curves to everything, and this is part of the process for me, learning about the camera and it's settings and such.
 
I had a Samurai and used it on my AF101. When I compared on a per pixel level what the difference was it became clear that an external recorder couldn't improve the footage in a noticeable way. Workflow became better but that was about it. IMHO AVCHD on the AF100 is as good as it gets.
 
My tests with the Samurai + AF100 and prores codec were similar. I did however see noticeable improvements in noise smoothing and highlight detail when using the dnxhd codec compared to the same footage in avchd.
 
Well, the problem does exist, and I would say, why not shoot a test at a higher quality capture to see if it's improved? The answer is yes, it was improved, but not that much. There are learning curves to everything, and this is part of the process for me, learning about the camera and it's settings and such.

Correct...The problem definitely exists if one stresses the sensor with over exposure. Capturing the "problem" with a higher quality codec only shows the "problem" at better quality. Its not a fix.

Learning any camera and settings via tests is a commendable and valuable activity to undertake.

My issue with a banding test such as yours is it sets off those that believe the camera has issues. eg endless threads about Highlights / Banding.

It is well proven that those that have learnt to operate the camera properly...do not have these issue. Therefore the "issues" are O.E (and inexperience)
 
Hi, I use the Hyperdeck v2 for prores 422hq capture, I followed a little advice on here and that was to drop coring to -2/-4 and allow a little noise into the image with the cine gamma. As you don't have the ugly compression artefacts to deal with and just noise, in post Neat Video can do a far better job of denoiseing the image. I get zero banding issues this way. Put a little 35mm grain back in and the footage looks really nice.

thanks for the test by the way, I nearly went with the Samurai but it would of ment not getting the Dp4 so went with the Hyperdeck and am very pleased I went with external recording!

Went through the other gamma settings, and I found SD norm has the least amount of banding, and noise was pretty even across all of them. Not too bad on the noise, nothing the client will ever notice.
 
Correct...The problem definitely exists if one stresses the sensor with over exposure. Capturing the "problem" with a higher quality codec only shows the "problem" at better quality. Its not a fix.

Learning any camera and settings via tests is a commendable and valuable activity to undertake.

My issue with a banding test such as yours is it sets off those that believe the camera has issues. eg endless threads about Highlights / Banding.

It is well proven that those that have learnt to operate the camera properly...do not have these issue. Therefore the "issues" are O.E (and inexperience)

Couldn't agree more Shooter. I'm just now starting to get into the settings, and I'm glad I am. I'm also learning more about the camera and how it performs, which is quite well for the price and the features it has.
 
Can I recommend that you test the camera in Default Settings (1-6) at some time early on so as you have a baseline knowledge before you apply Scene recipes.

Starting with presets designed by others... in conditions that you know nothing of... is a way of getting confused real quick!

Testing against the defaults shows one exactly what is happening when a setting is changed.
 
I don't know about anybody else, as mileages may vary. But I definitely see a difference between the internal AVCHD and DNxHD codec recorded with the Hyperdeck Shuttle 2. I don't even need to pixel peep or zoom 400% to see it. First, the colors from the DNxHD footage are visibly richer. Second, noise is much more distributed and smaller instead of macroblocking. Third, it keys better and also grades better. Fourth it's much easier to work with DNxHD in post than AVCHD. These reasons alone are enough for me to use an external recorder.
 
Thanks! Finally someone gets the same positive results with the DNxHD codec, though mine is with the Samurai. I had someone on a different post explain why technically those improvements were highly unlikely.
I just did some color correcting with Colorista 2 and MOJO and those improvements were magnified.
I am going to continue to trust my eyes and leave the technical assessments to others.
 
My experience with the test I did AVCHD (cam ) vs ProRes HQ (samurai ).

I placed one clip on top of the other in 2 Premiere CS6 video layers so I was able to switch between the 2 easily for instant and direct comparison of smae frame.

I was barely able to perceive a visual difference in any of the 3 monitors. Maybe a limitation of the monitors but the primary QC Monitor was a Panasonic HD broadcast monitor and the NLE monitors were fairly high end and calibrated to Bars and Pluge

What was noticeable was a difference in the scopes. ie the data.

That data makes a considerable difference in the post production - CC/ Grade, Compositing etc.

We have tested both codecs but it is difficult to "quantify" in any practical terms apart from its "easier", more "elastic" and "smoother" to work with.

The AVCHD is definitely not a slug to work with..it should be pointed out as well...unless there is ann issue such as under/over exposure.
 
What was noticeable was a difference in the scopes. ie the data.

That data makes a considerable difference in the post production - CC/ Grade, Compositing etc.
To back up what shooter's saying... there are reasons I get a little antsy whenever someone says "I'll just trust my eyes..."
http://web.mit.edu/persci/people/adelson/checkershadow_illusion.html
checkershadow_illusion4med.jpg
 
(for those who haven't seen this before; squares "A" and "B" are EXACTLY the same shade of grey... don't believe me? Sample it in PhotoShop and see).
 
I don't know. But I really never seen a case of 4:1:1 or 4:2:0 looking as good as 4:2:2 color-wise. To me, the color difference is always there, just by looking at it. When I bring it into color grade then things jump even more on your face. Besides, it's not a case of trusting your eyes only. It's the eyes, the numbers, the data.
 
422 is not adding colour information, it is adding colour resolution. I frame codec is nice to work with too.
 
Image Data is very interesting and the time I notice how much the eye can be tricked (by monitors) is when I legalise a shot for broadcast.

Our cameras generally produce an image that is non legal broadcast. Chroma and Luminance.

When soft clipping images to bring Chroma Levels and Luminance into line..it is amazing how much one can clip them and there is no apparent difference visually (in the monitors).

TheWFM and Vectorscopes are showing a massive shift but the images do not change at all.
 
You guys that have af100 and hyperdeck shuttle. What program and computer you use to grade dnxhd files. I ask because on pc (premiere cs5-6)dnxhd is useless for me.Dont record full range and premiere reads it as 0-255 file. Need to use prores to work with my computer.
 
You guys that have af100 and hyperdeck shuttle. What program and computer you use to grade dnxhd files. I ask because on pc (premiere cs5-6)dnxhd is useless for me.Dont record full range and premiere reads it as 0-255 file. Need to use prores to work with my computer.

That's interesting that you say DNxHD is useless on PC because Media Composer runs on PC and DNxHD is tailor made for it. So any of the Avid family editors will work with it. If you want a specialized grading software, best in the business-industry standard DaVinci Resolve works fine with DNxHD.
 
No, you're talking in a way that suggests the colours just pop when captured in 422 over 420 as if there is more colour information being captured or that the scene file we see on screen is somehow skewed to looking different when capture via SDI and looks different to the AVCHD and that's not the case. 422 is double the colour resolution of 420, thats it, hence why it's easier to key but we are gaining next to no extra colour information inside the 8 bit output. Lower compression via prores or dnxhd is reducing/removing compression artefacts and giving us I frame encoding but that's it, it doesn't suddenly bloom with colour.

Coming from a user of the AF100 with external recording via the hyperdeck.

By the way we're still waiting to see some of your work Adam, warts an all :)
 
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Today's mind#uck brought to you by Barry Green...fascinating.
checkershadow_illusion4med.gif
 

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