Thunderbolt 3 eGPU @ 5 Gb Max Bandwidth/sec

EDIT: After reaching out to Sonnet Tech, they recommend that this is only a representation issue and that the box is indeed correctly connected at 40 Gb/s.

macOS 10.15.3 - MacBook Pro 16-inch 2019

5 Gb/s but why not 40 Gb/s?

Thunderbolt 3 specs out 40 Gb/s over a USB-C connection, yet under Activity Monitor we only see 5 Gb/s.

System Information

PCIe x16 lanes show up in System Information with the eGPU, which is correct - but through Thunderbolt 3 only x4 lanes are accessible per specification so it’s difficult to know what the true bandwidth is between the computer and the eGPU enclosure.

Sony a7R IV Resolution comparison

Squarespace does not support uploading photos at anything near the 19,008 x 12,672 resolution that the pixel-shifted a7R IV sensor can provide. The comparative illustration below will have to suffice.

note how minuscule Full HD 1080p is

Sony A7R IV

Let’s get some of these specs out the door:

15 Stops Dynamic Range

61 MP (9504 x 6336) - Full Frame - Exmor R CMOS Sensor

240 MP Pixel-Shift Multi Shot

$3500 available July 18, 2019

5.5-stop 5-axis in-body Image Stabilization

BIONZ X Image Processor & Front-End LSI

567-Point Phase-Detection Autofocus

10 FPS still shooting

Dual UHS-II SD card slots

For the record: Hasselblad claims 14 stops of dynamic range from the Medium Format X1D II 50C, so for Sony to state 15 stops from a smaller Full Frame sensor is quite the remark. Or in other words; more pixels shoe horned into a smaller area.

Hasselblad: 50 MP in 44 x 33 mm

Sony: 61 MP in 36 x 24 mm

Not to be overlooked during Sony’s press release: The ECM-B1M digital microphone. Digital microphone? Yes! Meaning instead of an analogue signal processed by the on-board analog preamp (microphone-in), the signal goes straight to the camera CPU for recording to the SD card. One less step in the processing chain + no need to worry about microphone cable manufacturing quality. $350 available July 18 from B&H.

Video

4K UHD 3840x2160p 23.976 / 29.97

100 Mb/s H.264 Slog2/3 and HLG

4K from 20 MP 6K Oversampling crop of Full Frame sensor (same area/resolution as shooting with a6500 APS-C camera)

Read between the lines: The greatest video attraction of the a6500 ($1100) is that it uses the entire APS-C sensor to shoot 4K from Oversampled 20 MP 6K. Now you get that exact same footage while shooting video with the A7R IV since it takes precisely that crop from the middle of the 61 MP sensor. Yes the A7R IV is 3x the price but now you have one camera in the bag that executes both maximum resolution stills and excellent Super 35mm 4K video.

Unfortunately HDMI out is still 8-bit 4:2:2, but oh well life goes on. This is especially unfortunate since HLG is supported in camera yet said format is all but standardized as 10-bit H.265.

Blackmagic RAW 12:1 3840x2160p60

Newly added to the Blackmagic Pocket Cinema Camera 4K: Blackmagic RAW. Demosaicing is done in camera instead of DaVinci Resolve but that’s not to say 12:1 doesn’t take the RADEON Pro 560X to its limit and back. 194˚F is a hot chip.