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2.5K CinemaScope anamorphic raw on the 5D Mark III


Andrew Reid
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Hi Andrew,

First of all, thanks for keeping up the good work on EOSHD, great stuff, very inspiring.

Secondly, yeah 5D raw, here's looking at you kid. 

And then, I was wondering, for all of us LA7200 users, it would be nice to hear what you have to say about the 5D / LA combo in light of recent developments. I have been using the GH2 since full frame was problematic (vignetting) but does ML raw changes any of this??

Cheers,

Jo

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The LA7200 is lovely but on a full frame sensor it's not best suited...

 

It was designed for the small chip DVX100.

 

It works best at wide focal lengths, deep DOF, F4 to F11.

 

With a full frame sensor, wide focal lengths vignette with the LA7200 as they do any anamorphic adapter so you need to use a longer focal length. The LA7200 doesn't work very well with long focal lengths or the shallow DOF these lenses create.

 

You are better off saving up for an Iscorama or finding one for 70 euros in a second hand store like I did after 4 years of searching :)

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Hey Andrew, I think the aspect ratio is off in your video (the first one). It looks stretched horizontally, but compressing it so that the video frame (excluding black bars) is 16:9 fixes the stretch. As you're shooting in 4:3, you will get 16:9 with an anamorphic lens (which was the original use for the Panasonic anamorphic lens - to make a 4:3 camera record in 16:9). Just thought I'd let you know. :) Stunning footage regardless!

 

Here's what I mean:

 

[URL=http://imageshack.us/photo/my-images/12/80767918.png/]80767918.th.png[/URL]

 

[URL=http://imageshack.us/photo/my-images/809/65037090.png/]65037090.th.png[/URL]

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You only get 16:9 from 4:3 with a 1.33x anamorphic lens.

 

The ones from the film days are 2x anamorphic. Iscorama is a 1.5x stretch.

 

Update: corrected the video, should be 2560x1280 from the 1.5x stretch of the Iscorama.

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Hi Andrew,

Let me say I enjoy reading your blog everyday.

But if you could take an advice, I'd recommend you to double check all the tech info you posted today, because it's full of inaccuracies and technical misleadings.

For example, while a RAW to RGB conversion can actually be done with a 444 color sampling, that does not mean that the actual signal carries full color resolution for each of the channels. Such is the case of a CMOS bayer pattern sensor like the one in the 5D. While RAW recording clearly gets rid of ugly both compression artifacts and in camera video processing that throws away information, as long as it is limited to low resolution such as 1920x1080, it will never achieve a great luma and chroma resolutions, just because of the nature of bayer patter sensors. The only way of solving this is adding more resolution and downsampling in post. SO yeah, the raw can be 1920x1080 but the measured resolution will fall far behind that.

Anyway I didn't want to make a very long post, this is just one of many issues your article has (like calling 3K a digitally resampled anamorphic image).

You could double check your blog entry to avoid having newbies confused. I understand the ML hack is very exciting but facts and numbers still apply.

And I say this owning a 5Dmk3, a F35 and some Iscoramas as you do.  :D

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You only get 16:9 from 4:3 with a 1.33x anamorphic lens.

 

The ones from the film days are 2x anamorphic. Iscorama is a 1.5x stretch.

 

The video isn't off.

 

You're right, it's wider than 16:9, but it isn't as wide as you think, and it's stretched. Funny how your brain compensates if you've been looking at it for a while, though (which is something I've noticed before).

 

Here, look:

 

Top is the original aspect ratio.

 

Bottom has the video frame (including black bars) compressed to 3:2.

 

Blue circle added for easy comparison to the hoops in the background. Speaks for itself. ;) You can't argue that the hoops are at an angle, because they would be taller vertically and they are not. So, the conclusion is that it's stretched ever so slightly, but enough to be the first thing I noticed when I started watching your vid. Shoot a perfect circle head on if you want to see it yourself. Just trying to help.

 

aspectratioa.jpg

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You're right, it's wider than 16:9, but it isn't as wide as you think, and it's stretched. Funny how your brain compensates if you've been looking at it for a while, though (which is something I've noticed before).

 

Here, look:

 

Top is the original aspect ratio.

 

Bottom has the video frame (including black bars) compressed to 3:2.

 

Blue circle added for easy comparison to the hoops in the background. Speaks for itself. ;) You can't argue that the hoops are at an angle, because they would be taller vertically and they are not. So, the conclusion is that it's stretched ever so slightly, but enough to be the first thing I noticed when I started watching your vid. Shoot a perfect circle head on if you want to see it yourself. Just trying to help.

 

aspectratioa.jpg

 

 

Hey Andrew, I think the aspect ratio is off in your video (the first one). It looks stretched horizontally, but compressing it so that the video frame (excluding black bars) is 16:9 fixes the stretch. As you're shooting in 4:3, you will get 16:9 with an anamorphic lens (which was the original use for the Panasonic anamorphic lens - to make a 4:3 camera record in 16:9). Just thought I'd let you know. :) Stunning footage regardless!

 

Here's what I mean:

 

80767918.th.png

 

65037090.th.png

 

 

 

Probably due to the fact that while Iscoramas are rated as x1.5 anamorphic lenses, they're closer to x1.41 compression ratio if you measure them with a perfect circle. At least that's my experience with the ones I've had.

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As you said it youself you can do raw to RGB with 444 color sampling. Sure there's some interpolation but it isn't inaccurate to call it 444.

 

Same as calling the Epic 4K, 4K. It isn't REAL 4K. But it's still 4K. Get what I mean?

 

Also you don't actually know how the sensor is sampling 1080p from the full 6K resolution. It could be oversampling and downsampling from a higher resolution to achieve the 1080p raw for all you know. As you said, the way to get great luma and chroma res is adding more resolution and downsample. The image is so good that could well be happening on the 5D's sensor.

 

If you'd like floating point precision in terms of facts and figures from me, I'd be the first to admit I am not a mathematician but a filmmaker.

 

There's some stuff I'm still working out as I go, we learn every day as filmmakers and my blog is part of me learning as I go, sharing as I go. I think the anamorphic aspect ratio needs to be checked too by peer review, since 1920x820 is 2.39:1 and that is how I derived 3000x1280 - it looks however like the anamorphic isn't quite giving us that wide aspect ratio from 4:3 like I expected. Maybe it should be 2.5K x 1280. All to be tried! Still early days.

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Probably due to the fact that while Iscoramas are rated as x1.5 anamorphic lenses, they're closer to x1.41 compression ratio if you measure them with a perfect circle. At least that's my experience with the ones I've had.

 

I think 2580 x 1280 looks about on the money, which makes sense as 1720 x 1.5 = 2580!

 

5draw-4-3-iscorama-1-5.jpg

 

I got 3000 x 1280 by assuming the Iscorama would give me 2.39:1 from 4:3. Seems it does not.

 

Will have a further look into this and likely re-upload the video tomorrow.

 

Cheers guys.

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As you said it youself you can do raw to RGB with 444 color sampling. Sure there's some interpolation but it isn't inaccurate to call it 444.

 

Lol, it's true you can. But in the same way I can plug my old VHS into a HDCAM SR deck and record at 1080p 444, and while the signal will be actually full HD with full chroma resolution...                     well you get the point right?

 

Chroma sampling and debayering are often mixed and confused. I think it's normal to do so. But it would be great if people get the difference. 

For example, since you're mentioning F35 vs 5D. For each pixel in the final 1080 resolution, the F35 had 6 pixels in the sensor and the camera downsampled them to get that one pixel. That means each pixel has full red, green and blue information. No interpolation. 

Now, compare that with a bayer pattern sensor like the one the 5D uses, where only 25% of the pixels go to red and blue. From 25% to 100% there's a 75% interpolation gap there. Yep, that's a big gap to fill in compared to a F35 right?

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I agree, good to know the info. Thanks Miguel.

 

It is good to bear this in mind with any bayer sensor. Red is interpolating to get 4K resolution, whilst the Sony F65 over-samples from 8K to do true 4K and true 4:4:4 colour.

 

With the anamorphic mistake - totally put my hands up to this one. In my haste to get on with shooting, I assumed I was getting 2.39:1.

 

It is actually 2:1 and the horizontal resolution should be 2560 not 3000. This is quite handy actually as it perfectly matches the native resolution of my Dell display.

 

Here are the other anamorphic resolutions for 4:3 and 3:2...

 

2x anamorphic from 4:3 (1770x1280) = 3540 x 1280 (2.66:1)

2x anamorphic from 3:2 (1920x1280) = 3840 x 1280 (3:1)

 

1.5x anamorphic from 4:3 (1770x1280) = 2580 x 1280 (2:1)

1.5x anamorphic from 3:2 (1920x1280) = 2880 x 1280 (2.35:1)

 

Do those aspect ratios look right? I'm not too sure.

 

I'll re-upload the video and it should look perfect.

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The fact that the mkiii is in the same conversation as the F35 is pretty scary. The F35 is not even raw, lol. And the doesn't handle low light well. And it is huge and unwieldy compared to the mkiiii. And it's old and obsolete. And it probably costs 10k to have it repaired. Give me the mkiii with raw ALL day long if the image is comparable in any way.
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I agree, good to know the info. Thanks Miguel.

 

It is good to bear this in mind with any bayer sensor. Red is interpolating to get 4K resolution, whilst the Sony F65 over-samples from 8K to do true 4K and true 4:4:4 colour.

 

With the anamorphic mistake - totally put my hands up to this one. In my haste to get on with shooting, I assumed I was getting 2.39:1.

 

It is actually 2:1 and the horizontal resolution should be 2560 not 3000. This is quite handy actually as it perfectly matches the native resolution of my Dell display.

 

Here are the other anamorphic resolutions for 4:3 and 3:2...

 

2x anamorphic from 4:3 (1770x1280) = 3540 x 1280 (2.66:1)

2x anamorphic from 3:2 (1920x1280) = 3840 x 1280 (3:1)

 

1.5x anamorphic from 4:3 (1770x1280) = 2580 x 1280 (2:1)

1.5x anamorphic from 3:2 (1920x1280) = 2880 x 1280 (2.35:1)

 

Do those aspect ratios look right? I'm not too sure.

 

I'll re-upload the video and it should look perfect.

 

Glad you got that right. I was thrown a little off of the video because of the stretchiness of the footage and was thinking the numbers along the way, thinking about giving a heads up. The images were still amazing, but I'll have to watch it again once it's on the right aspect ratio!
You should get more recognition around the web. I guess there are a lot of people just watching out for their own garden.

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Footage looked... strange to me, I guess. Color was nice, but it just seemed... I dunno. Fuzzy. Blurry. Can't really put my finger on it. It gave me a headache to watch in full screen. Some kind of distortion to the image when it wasn't focused correctly. Maybe it's just me, though. 

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Hi Andrew,

 

Thanks a lot for this very in-depth post.

 

- Could you please give more details about this?:

 

"There’s no recording limit as the 4GB file size limit of FAT has been broken and the camera uses ExFat formatted cards"

 

Isn't the CF card formatted as FAT32 with a 4GB limit? didn't understand what you mean.

 

- It would be great if you can post a thorough article about current available choices of anamorphic lenses (used and news), AND how to do a good job working with them when also shooting with normal lenses in the same sequence of the film.

 

Thank you very much

 

Regards

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