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  • Hey all, just changed over the backend after 15 years I figured time to give it a bit of an update, its probably gonna be a bit weird for most of you and i am sure there is a few bugs to work out but it should kinda work the same as before... hopefully :)

Got 6K ? ( link to my LA vista shoot test )

I just noticed the RED education 101 email today, topics covered are: Resolution, aliasing, OLPF, and bayer sensors.

It's a good read for those who need more information on what's going on inside the camera to make images.
 
shot in India. Happy with detail !

shot in India. Happy with detail !

Update: I just returned from 3 weeks shooting in India.

All my footage will be processed for actual 4K results.

Link to 6K still from motion shot with Scarlet using 4K mode, Canon 17-55 2.8 , this shot at f5.1 and 21mm :

http://www.mediafire.com/?8hfytb52qjjgofb ( load into an image viewer to see the detail, as you have to zoom in to see it. )

I can't believe I'm shooting motion pictures at this level of detail. Should look nice on a 84" UHD monitor.
 
Justin Batchelor said:
That's pretty radical detail on a wide. More.....?
Click to expand...

I'm preparing for the edit now, and will post more stills in the future.
I think most Red shooters are delivering 1080p and really don't care about this much detail now anyhow.
After the UHD TV sets are more common, this might change however. This is when 4K evolves from a promise to something you can enjoy in motion at home, if you really did capture 4K resolution on the 4K camera you used.
 
I don't understand the aliasing - it looks more like scan-lines; I know you mentioned it in the past, and I know the OLPF reduces aliasing (I thought it was by "softening/blurring" the image), but I don't understand why it shows up like overlapped scanlines and/or motion artifacts? Should it not just be a square pixel?

The other thing I don't understand is how not having the OLPF is cause for more processing requirements (the secret sauce you're applying.) What does it look like directly out of the sensor and why does that look less perfect then, say, the BMCC which has no OLPF and looks pretty much fine (slightly more susceptible to texture moire, but its uncompressed 2.5k it's sharper than Scarlet 4k at 6:1)?
 
When you shoot with no OLPF problems occur when the sensor pixels occasionally line up with something in the scene that almost matches the bright-dark-bright-dark pattern of a scene pattern, say a grill on a car or a distant fence or a brick wall in perspective. Because the red and blue sensor sites have significant gaps between them the camera has no idea what's really going on as the pattern slowly moves across the sensor.
This can cause color strobing where the debayer mistakes are happening.

A more extreme example: imagine a chess board. Now a sheet of black cardboard with some small holes punched in it in a square grid with the same spacing as the chess board. Lay the cardboard on the chess board.
This is like the sensor 'seeing' the chess board with the holes being pixels. So you can slide around the punched cardboard on the chess board making the holes show all black or all white, meaning a picture resulting in a perfectly white flat image or a flat black picture, or strange combinations that are equally false representations of the real checkered pattern underneath.
So the camera sensor can be tricked by this type of thing.
It turns out that this usually is not happening in real natural scenes and only happens when your focus is really good.
The Black Magic camera does exhibit the issue. Line skipping DSLR's even more as they tend to skip lines of the sensor to allow the video frame rates.
So when I review my shots each night, I actually am happy when I see these aliasing image faults on small details in the image, as it means I hit focus properly on the take.
My post processing harvests these aliased images and produces more detail than possible if the image was blurred at the sensor by the 'blunt instrument' called the OLPF.
This is how I can get a 6K image from a 4K shoot.
Now I don't really want a 6K image, but it lets me shoot 3K high frame rates and still get a REAL 4K, which is a bonus for me.
Plus I'm able to resolve a full 4K for display on a UHD TV set. Regular RED footage, even from a current Epic shooting 5K has a hard time getting a sharp picture on a UHD TV set.
The sharpest demo footages at CES running in the booths of various manufacturors was not sourced from RED cameras. The stuff running at the Toshiba booth on the REDRAY looked rather soft as well.
These UHD TV sets are the litmus test for 4K. Having 11,520 pixels across on UHD TV sets shows no mercy for soft images.
RED has the Dragon sensor which has a much lighter OLPF on it. RED says sometimes they have no idea what they are doing sometimes. They are learning. This is good.
The lighter OLPF on Dragon and the follow along 're engineered' demosaic that it now requires will certainly make a REAL 4K image that will look amazing on the UHD TV sets.
Focus assist will be a challenge I hope they tackle as well. But for current cameras I fear that they are out of 'cycles' to use more advanced focus processing strategies.

I am so amazed with the footage I just shot in India with a rig that fit in my backpack at under 30 lbs total weight.
The 65mm camera body used in shooting 'Samsara' weighed 40lbs without lens or magazine! I'm getting images that will look just as sharp on a UHD TV, which is totally amazing.



Mike P. said:
I don't understand the aliasing - it looks more like scan-lines; I know you mentioned it in the past, and I know the OLPF reduces aliasing (I thought it was by "softening/blurring" the image), but I don't understand why it shows up like overlapped scanlines and/or motion artifacts? Should it not just be a square pixel?

The other thing I don't understand is how not having the OLPF is cause for more processing requirements (the secret sauce you're applying.) What does it look like directly out of the sensor and why does that look less perfect then, say, the BMCC which has no OLPF and looks pretty much fine (slightly more susceptible to texture moire, but its uncompressed 2.5k it's sharper than Scarlet 4k at 6:1)?
Click to expand...
 
Thanks Les. I understand why it causes moire, but I didn't understand why it was manifesting across an entire scan line equally (I didn't consider the bayer pattern's..uhh...pattern).

And, yes, I fully expect 4k displays to make 4k red footage look noticeably weaker as it's sans a downscale (it should still look leagues beyond C300 upscaled to 4k though). An UHDtv has 3840 red, green, and blues dots, which form a "single" pixel, whereas Scarlet's 4k is 3840 (okay, 4096) total, which is converted to RGB dots (apparently at 80% resolving power)... A few years back I remember all the "pundits" saying that 3CCD 1080p cameras could be considered "6k" CMOS because they are three 1920x1080 arrays (one for red, one for blue, one for green)... It'd be ironic if we actually see the corner-cutting of CMOS manifested as a noticeable lack of sharpness with the release of 4k displays. Actually, I was under the impression that it's partly why RED added 4.5k to R1; so that it resolved an actual 4k amount of res (I hoped they would give that kind of 4.5k love to Scarlet, but it looks like they're understandably leap-frogging to Dragon). To be fair, everyone is using CMOS now, but they could be using trickery/magic (in their OLPF) to make their footage that much crisper when it's 1:1.

It'd be interesting if Dragon's "lighter" OLPF can be used on MX with positive results (where did you read about Dragon's OLPF? I haven't seen any mention of it). I presumed they tailored the current OLPF for MX, but I'm not sure if it makes a difference when shooting at 5k on Epic or 4k cropped on Scarlet/Epic. Something tells me it would. What bothers me is that post sharpening adds artifacts before it can make MX footage at 2k as sharp as 1080p footage out of, say, an XH-A1 or even large (but non-4k) sensor cameras like an AF100 (I can't think of any reason/cause other than the OLPF, REDcode compression, or the actual sensor... or a combination.) I expect, and you seem to be implying, that it'll be the same at full/4k resolution on UHD screens.

I'd like to take raw frames from an Alexa (upscaled to 4k), Epic (downscaled to 4k), and Scarlet, all with the same lens, and see how different they are when viewing 1:1... Something tells me the results won't be drastically different (but technically they should be).
 
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Wow, that is the most detailed still I've ever seen on Reduser—it also has a natural fidelity I like. I hope the new dragon sensor's OLPF is as good as the method you're using.
Les, care to share any footage when you're done? This is simply amazing—great job!

Les Dittert said:
Update: I just returned from 3 weeks shooting in India.

All my footage will be processed for actual 4K results.

Link to 6K still from motion shot with Scarlet using 4K mode, Canon 17-55 2.8 , this shot at f5.1 and 21mm :

http://www.mediafire.com/?8hfytb52qjjgofb ( load into an image viewer to see the detail, as you have to zoom in to see it. )

I can't believe I'm shooting motion pictures at this level of detail. Should look nice on a 84" UHD monitor.
Click to expand...
 
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Thanks Elan,
The editing is under way. I shot about 1TB on the trip. The result will be a non narrative piece between 5 and 10 min.
I purchased a 4k monitor which is now affordable so I can see the footage the way it should be, all at the same time!



Elan Gunos said:
Wow, that is the most detailed still I've ever seen on Reduser—it also has a natural fidelity I like. I hope the new dragon sensor's OLPF is as good as the method you're using.
Les, care to share any footage when you're done? This is simply amazing—great job!
Click to expand...
 
Les I cant wait to see your frames ;)
 
That's great—thanks!

Les Dittert said:
Thanks Elan,
The editing is under way. I shot about 1TB on the trip. The result will be a non narrative piece between 5 and 10 min.
I purchased a 4k monitor which is now affordable so I can see the footage the way it should be, all at the same time!
Click to expand...
 
Jonathan Cape said:
That is a great way to create high res, it's a shame there isn't a display / array of displays to showcase that kind of resolution, but that would be incredible to create a gallery / event that did that. Of course there's always print, but in video that would be incredible... I wonder if the RED team has though of projection stitching for their RED laser projector... 24K projector anyone? (we just need a big wall)...
Click to expand...

We did a 20k 360 98fps for Bank of america, did not see the installations myself but apparently they showed almost 1/4 of the canvas at the time and pan tilt and so on was gesture driven... It's amazing what it takes to get people into greater dept nowadays :)
 
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