Canon 5D Mark IV

Started by SiSS, August 11, 2016, 11:11:29 PM

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a1ex

Sneak preview of what's inside a dual pixel RAW:



Middle: main image data; Laurent calls it "unsliced"; probably (a+b)
Right: what Laurent calls "unslicedB"
Left: "unsliced" - "unslicedB"

https://twitter.com/autoexec_bin/status/772943052797276160
https://twitter.com/hirax/status/772784433761951744

Noise levels in optical black area: 3.55 for main, 3.47 for B, 3.49 for difference. White level 16383, black level 2048, useful range 14335 DN.

Image B has 1 stop of extra highlight detail, compared to main. DR (simplified): log2(14335 / 3.54) = 12 stops in main image, 13 stops if you take the highlights from B.

edit: some rough notes: 5d4-dual-pixel.html

dfort

Well this is interesting. I worked on 3D productions and that does look very much like left eye/right eye images. Don't know what to make of the third eye!

Shooting 3D with a single lens and sensor was being developed by Lytro. Their first product's claim to fame was that you could adjust the focus in post. However they never caught on and the company no longer manufactures consumer products, though Lytro is still developing some interesting VR technology.

Wonder if there's a 3D option coming for the 5D4.


chris_overseas

Dual Pixel RAW is certainly looking intriguing. I'm curious to know if the hardware can control the ISO of the A and B pixels separately, opening up the possibility of an improved type of dual ISO. [Edit: I guess this is unlikely, given dual ISO works by alternating ISO every second row rather than by column]

There's a few new pieces of info about the 5D4 in general in this interview:

http://www.birdsasart-blog.com/2016/09/03/canon-5d-mark-iv-eos-1dx-mark-ii-and-5ds-r-top-canon-tech-rep-rudy-winston-answers-my-questions-and-yours/

Interesting to see that using UHS-II SD cards might give worse performance than UHS-I.
EOS R5 1.1.0 | Canon 16-35mm f4.0L | Tamron SP 24-70mm f/2.8 Di VC USD G2 | Canon 70-200mm f2.8L IS II | Canon 100-400mm f4.5-5.6L II | Canon 800mm f5.6L | Canon 100mm f2.8L macro | Sigma 14mm f/1.8 DG HSM Art | Yongnuo YN600EX-RT II

Walter Schulz

Quote from: chris_overseas on September 06, 2016, 08:17:56 AM
Interesting to see that using UHS-II SD cards might give worse performance than UHS-I.

That's quite old news. You can find some of the cards affected in http://www.cameramemoryspeed.com/reviews/card-readers/transcend-usb-3-0-card-reader-rdf5/
All the cards marked UHS-II and running below 70 MByte/s writing should not be used in Canon cams with fast UHS-I slots:
- Lexar Professional 1000x microSD UHS-II 32GB (64 GB and up are performing better)
- Delkin 1900x UHS-II 32GB
- SanDisk Extreme Pro 280MB/s UHS-II 32GB (all of them AFAIK, but new Extreme Pro generation (275 MB/s) not affected)
- Panasonic MicroP2 UHS-II 32GB
and maybe others.

squig

I'm getting the impression from the cinema5D article and video that 1080p is downsampled not pixel binned.

eduperez

Quote from: dfort on September 06, 2016, 02:38:17 AM
Well this is interesting. I worked on 3D productions and that does look very much like left eye/right eye images. Don't know what to make of the third eye!
Wonder if there's a 3D option coming for the 5D4.

Well, it is a left/right eye image, only that the distance between the eyes is in the order of magnitude of the diameter of the front lens, so I would not expect much 3D effect from this; here you have a quick anaglyph conversion from the image posted above (red filter on left eye, blue filter on right eye):



The "third eye" in that example is created during the RAW conversion by merging the images from both eyes; as far as I know, it should not be relevant to 3D.

EDIT: Another interesting facts about this technology:
* Both images will be automatically aligned on the focusing distance: objects closer to the camera than the focusing plane will appear to come out of the monitor, and objects further away than the focusing pane will appear to be inside the monitor; the focusing plane will always match the surface of the monitor.
* The amount of 3D effect will depend on the aperture used to take the image: the larger the aperture, the larger the effect; in images taken using the hyperfocal technique, there will be no 3D effect at all.



Levas

I downloaded some canon 5d4 raw files from that swedish site, curious about how much focus shift can be done.
Downloaded the newest Digital Photo Professional 4 (version 4.4.30.2) from the canon website.
But it can't open/recognize the 5d4 files...

Does anybody know where can I download the actual DPP4 version which can open the CR2's from the 5d4 ?



Levas

By the way, Interesting stuff, that extra stop in the highlights  :D
According to that ND patent, it's a ND filter in the microlens which can be switched on and off...so it's not done on CMOS level, like dual iso.
I guess this means it's fixed at only one stop of difference, between the two images.

a1ex

Here, it looks like Canon simply adds the signals from both subpixels and clips the result. The patent makes it possible to push it even further, but I doubt this one is used here.

The extra highlights in the second image will effectively give a true ISO 50. The Swedish sample is at ISO 400, but the comments at http://www.rawdigger.com/howtouse/Canon-dual-pixel-technology confirm my hypothesis.

However, it's not clear to me whether selecting ISO 50 in Canon menu actually brings that extra highlight detail in the main raw image. The comments on the RawDigger website seem to suggest this is not the case, but I'm not 100% sure.

Simonwb

Well, my 5D4 has arrived but I won't get time to play with it until this weekend.  I could try to shoot some comparison footage - would you like to see any formats in particular?
5D3.123 | 5D4 | C100ii | 16-35 f4 | 24-105 f4ii | 70-200 f2.8ii | 50 f1.2 | 100 f2.8 | Samyang 16, 24, 35, 50, 85, 135

ph2007

https://www.youtube.com/watch?v=W0S8shTk94E
looks like the dual pixel not as what we expected nothing come close to lytro :(

a1ex

Quote from: Simonwb on September 08, 2016, 06:42:40 PM
Well, my 5D4 has arrived but I won't get time to play with it until this weekend.  I could try to shoot some comparison footage - would you like to see any formats in particular?

Yes, please.

Our friends from darktable are also looking for samples to add support for 5D4 in their next version, so I'm including their requirements as well.

To check white levels (for darktable):
  - take a picture at every single ISO, in both dual pixel and regular (full-sized) raw mode.
  - every picture should have some overexposed highlights.

To check crop area (for darktable):
  - a fully clipped sample at ISO 100, 30s, fully open aperture. Both dual and regular.

For color profiling:
  - preferred (for darktable): https://encrypted.pcode.nl/blog/2010/06/28/darktable-camera-color-profiling/
  - easier (good enough for me): a static colorful scene, taken with both 5D4 and another full-frame Canon camera. Same settings, same lens, same framing. Both sunlight and tungsten light (doesn't have to be the same scene). Regular raw only, ISO 100.

For checking the dynamic range and SNR curve:
  - prepare a HDR static scene (a desk lamp pointed towards the camera, and some black items near it, something like this).
  - if you are in PAL land, and your light source flickers, use a shutter speed of 1/50, 1/25 and so on.
  - defocus the lens
  - for every ISO:
      - choose a shutter speed and aperture that gives some clipped highlights and some deep shadows in the same picture
      - take two pictures using the built-in intervalometer (no motion between them)
      - take a bracketed set of images, centered at the settings used for the previous step (5 x 1 EV should be fine).
  - dual raw only.

For playing with the dual pixel refocusing tricks:
  - a resolution chart or some fine print, taken with perfect focus, front focus (various degrees) and back focus (various degrees).
  - any other test pictures you consider relevant for this feature, focus-bracketed in the same way.
  - repeat at various apertures and focus distances (not extensive coverage, just some random configurations of your choice)
  - ISO 100, dual raw only, with as little camera motion as possible.

For playing with super-resolution tricks (you know, getting a 60-megapixel picture):
  - with a zoom lens, take pictures of something with fine details (resolution chart, fine print, textures that give heavy aliasing, whatever) at a few focal lengths, with slightly bracketed focus, at the aperture setting where your lens is the sharpest.
  - ISO 100, dual raw only, with as little camera motion as possible.

You don't have to do all of these at once; it will probably take more than one weekend to capture everything I've asked for. And it will probably take me months to analyze all that :D

For me, individual files on a FTP server would work best, but archives (separate for each subtask) should work as well. I prefer simple links (accessible from a text-based browser) and files named properly (so I can recognize what they are before downloading).

Thanks, hope my request is not too overwhelming. Of course, other 5D4 owners are welcome to help.

rawvideo

Quote from: Simonwb on September 08, 2016, 06:42:40 PM
Well, my 5D4 has arrived but I won't get time to play with it until this weekend.  I could try to shoot some comparison footage - would you like to see any formats in particular?

I would very much like a night scene of a street or something similar, mostly dark with a few bright lights (streetlamps), high ISO, maybe the highest the 5DIII does with auto iso and then 2 raws with the same image and lens from the 5DIII and 5DIV. No longtime exposures, just fast enough to be handheld. :) To see if there is any improvement for my lowlight theater photography (besides the now actually and finally visible focus points).

MitchLally

I got my Mark IV yesterday. Doing a bunch of tests and I dared try to record 4K 24p to my Sandisk 95mb/s SD card. It recorded an uninterrupted 16 minute file (63GB single file) to the card.

I guess this is good news for the SD slot speed?

Walter Schulz

Thanks! Seems to be legit to say Canon has implemented fastest UHS-I mode (UHS104/SDR104: 99.18 MiByte/s) in 5D4, too.

Simonwb

@a1ex @rawvideo

Will do, I'll let you know how I get on.
5D3.123 | 5D4 | C100ii | 16-35 f4 | 24-105 f4ii | 70-200 f2.8ii | 50 f1.2 | 100 f2.8 | Samyang 16, 24, 35, 50, 85, 135

chris_overseas

EOS R5 1.1.0 | Canon 16-35mm f4.0L | Tamron SP 24-70mm f/2.8 Di VC USD G2 | Canon 70-200mm f2.8L IS II | Canon 100-400mm f4.5-5.6L II | Canon 800mm f5.6L | Canon 100mm f2.8L macro | Sigma 14mm f/1.8 DG HSM Art | Yongnuo YN600EX-RT II

budafilms

Sorry if the girl is the girlfriend or wife of someone here,  but, I think I will found her and make lot of videos ;)

(5d IV video)

https://www.youtube.com/watch?v=T5rn1ZnnSTY

Other girl to find:

https://www.youtube.com/watch?v=VHpfUcN0hLY

Vote: girl 1 or girl 2

:)

rawvideo

That 4k Video looks like upscaled 1080p. :D I've seen crisper 4k content, but maybe the small depth of field makes it look softer than usual..

a1ex

Depth map (two algorithms):




First algorithm (online demo):
http://demo.ipol.im/demo/78/archive/?key=F9DAF4DB86A22329D968CC5ADF813934

Second algorithm is from OpenCV 3.x (tutorial):


import numpy as np
import cv2

# read input images
imgL = cv2.imread('A.jpg',0)
imgR = cv2.imread('B.jpg',0)

# compute the depth map
stereo = cv2.StereoSGBM_create(minDisparity=-8, numDisparities=16, blockSize=15)
disparity = stereo.compute(imgL,imgR) + 128

# convert to 8-bit (required by medianBlur)
disparity = np.clip(disparity, 0, 255)
disparity = disparity.astype(np.uint8)

# clean up the depth map a bit
disparity = cv2.medianBlur(disparity, 15)

# adjust levels to increase contrast (hardcoded)
disparity = np.clip((disparity.astype(np.int32) - 80) * 4, 0, 255);

# save the depth map image
cv2.imwrite("dmap.jpg", disparity)


Can you get better results?

chris_overseas

Looks like stereoscopic images are possible, with quite good results: https://www.dpreview.com/forums/post/58326573
EOS R5 1.1.0 | Canon 16-35mm f4.0L | Tamron SP 24-70mm f/2.8 Di VC USD G2 | Canon 70-200mm f2.8L IS II | Canon 100-400mm f4.5-5.6L II | Canon 800mm f5.6L | Canon 100mm f2.8L macro | Sigma 14mm f/1.8 DG HSM Art | Yongnuo YN600EX-RT II

dragit

Hi everyone, long time reader, first time poster...

Just wondering what people think the likelihood is of frame rates higher than 50/60 are at 1080 in the future with ML?

I can live with quality of the H264 codec and haven't got time for the current RAW workflow, but would love the ability to shoot 100/120FPS like the 1DX ii 1080.

cheers

Greg

Who said that ML will support 5D4?

1Dx II has a faster sensor. If you compare full-res FPS, 5D4 should 80-90 FPS.