Difference between revisions of "AXIOM Beta"

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===AXIOM Beta PCB Stack Concept===
===AXIOM Beta PCB Stack Concept===
Version 1:
[[File:PCB-Illustration-01.jpg | 700px]]
Seen from the back side:
[[File:Beta_pre03_1024x640.png | 700px]]
Version 2:
[[File:Pcbstack02-V3.jpg | 700px]]

Version 3:
Version 3:
Line 201: Line 189:

[[File:PCB_Stack_Dimensions_01.jpg | 700px]]

===Image Sensor Frontend===
===Image Sensor Frontend===

Revision as of 11:27, 12 July 2015

1 Printed Circuit Boards

Validation Guide:

PCB Component Footprint Validation Procedure


Beta Main Board

Beta Power Board

Beta CMV12K THT Sensor Board

Beta CMV12K ZIF Sensor Board

Beta Interface Dummy Board

The Beta uses a Microzed:


2 AXIOM Beta Topics

2.1 Active Battery Mount

20140930134156-BETA Zeiss Battery2.jpg

Battery mount for NP-F970/F750/F550 batteries to power the AXIOM Beta. Includes power usage and capacity monitoring to estimate remaining charge and time remaining.

More Thoughts on Power.

2.1.1 InfoLithium Protocol

Proprietary protocol from Sony that exchanges metadata between batteries and devices. Expected data inside the protocol includes: charge cycles, battery ID, remaining total capacity, remaining current capacity, etc. Only official Sony batteries incorporate this protocol, cheap replacement parts don't and some Pro Sony cameras refuse operation with batteries without InfoLithium communication. Decrypting this protocol could give us more insight into the battery but is not essential as we can measure the discharge curve and estimate remaining capacity rather accurately that way. Hacking References



2.2 Dictator Remote Controller




2.3 Image Processing Pipeline

Draft pipeline taken from AXIOM Alpha for now.

Image Acquisition Pipeline:


HDMI Image Processing Pipeline:


2.3.1 Image Processing Nodes Debayering

A planned feature is to generate this FPGA code block with "dynamic reconfiguration" meaning that the actual debayering algorithm can be replaced at any time by loading a new FPGA binary block at run-time. This tries to simplify creating custom debayering algorithms with a script like programming language that can be translated to FPGA code and loaded into the FPGA dynamically for testing. Image Overlays

Full HD framebuffer that can be altered from the Linux userspace and is automatically "mixed" with the real time video from the image sensor. (https://www.apertus.org/pong-project on the AXIOM Alpha was implemented exactly with this method)

We still need to decide if a color palette here is sufficient or how many colors we would need. 32 bit image with Alpha channel might be an unnecessary overkill here.

This feature could also be used to draw live histograms/scopes. Peaking

Peaking marks high image frequency areas with colored dot overlays. These marked areas are typically the ones "in-focus" currently so this is a handy tool to see where the focus lies with screens that have lower resolution than the camera is capturing.

Handy Custom Parameters:

  • color
  • frequency threshold

Potential Problems:

  • there are sharper and softer lenses so the threshold depends on the glass currently used. For a sharp lens the peaking could show areas as "in-focus" if they actually aren't and for softer lenses the peaking might never show up at all because the threshold is never reached Image Blow Up / Zoom

Digital zoom into the center area of the image to check focus.

As extra feature this zoomed area could be moved around the full sensor area.


This feature is also related to the "Look Around" where the viewfinder sees a larger image area than is being output to the clean-feed.

This re-sampling method to scale up/down an image in real-time can be of rather low quality (nearest neighbor/bilinear/etc.) as it is only for preview purposes. Matrix and LUTs

3x3 / 4x4 Matrix

AXIOM Alpha uses one LUT per color channel.

Maybe a 3D LUT (17×17×17) is possible at a later point: http://en.wikipedia.org/wiki/3D_lookup_table

2.4 Lens Mounts

Picture of a Nikon F bayonet mount.
Mount Nikon F Canon EF Micro Four Thirds
Type Bayonet
Compatible Lenses Nikkor FX Nikkor DX EF EF-S (optionally)
Image Circle Size Full Frame
ø 43.3 mm
ø 28.4 mm
Full Frame
ø 43.3 mm
Canon APS-C
ø 27.3 mm
"Half Frame"
ø 21.6 mm
Throat 44 mm 54 mm ~38 mm
Flange focal distance 46.5 mm 44 mm 19.25 mm
Axiom Beta
Sensor Compatibility
Four Thirds
Four Thirds

More Details: Lens Mounts

2.4.1 Passive EF Mount

2.4.2 Passive Nikon F-Mount

Measured Bayonet Thickness: 1.3mm

2.4.3 Passive Micro Four Thirds Mount

2.4.4 Active Canon EF Mount

2.5 4K RAW PC recording option


2.6 Enclosure Design


Body Design Options


Switchable ND Filters not planned currently

Common and widely available peltier elements are 40x40mm (move it closer to fan?)

2.7 Electronics

2.7.1 AXIOM Beta PCB Stack Concept

Version 3:


PCB Stack Concept V03 02.jpg

Version 4:


All dimensions are still not final! Work in progress...

File:PCB Stack Concept V03 02.pdf

PCB Stack Dimensions 01.jpg

2.7.2 Image Sensor Frontend

It is planned to incorporate a glass filter slot between lens mount and lens base for placing an IR-cut-off filter or OLPF with IR-cut-off coating in the light path.

for Truesense KAC12040

Dimensions (inches if not stated otherwise):

Kac12040SensorFrontEndDimensions01.jpg Image Sensors

Graphic that compares the different Sensor Sizes and Lens Image Circles of the Axiom Beta
Axiom Beta Model 16mm Four Thirds Super35
Brand CMOSIS ON Semionductor
(prev. Truesense/Kodak)
Model CMV2000 KAC12040 CMV12000
Shutter Type Pipelined Global Shutter Global & Rolling Shutter Pipelined Global Shutter
Color filter Array Bayer (Color model)
None (B/W model)
IR filter no
Anti-Aliasing Filter (OLPF) no
Size 10.6 mm × 5.94 mm
ø 12.1 mm
18.8 mm × 14.1 mm
ø 23.5 mm
22.5 mm × 16.9 mm
ø 28.2 mm
Crop Factor Full Frame ∕ 3.56
16mm Film ∕ 1.05
Full Frame ∕ 1.84
Four Thirds ∕ 0.96
Full Frame ∕ 1.54
Super35 ∕ 1.10
Aspect Ratio 16:9 4:3 4:3
Pixel Resolution (h × v) 1920 × 1080 4000 × 3000 4096 × 3072
Pixel Size 5.5 µm 4.7 µm 5.5 µm
Dynamic Range 10 stops
15 stops (HDR mode)
9.3 stops (Gobal Shutter)
12 stops (Rolling Shutter)
10 stops
15 stops (HDR mode)
Sensitivity 200 ISO ~ 400 - 1250 ISO
Max Frame Rate @ Bit Depth 340 fps @ 10 bit
70 fps @ 12 bit
110 fps @ 8 bit
70 fps @ 10 bit
30 fps @ 12 bit
10 fps @ 14 bit
300 fps @ 10 bit
180 fps @ 12 bit
More info

2.7.3 Shields

The Axiom has 2 medium speed IO interfaces to be used with "shields".

  • One 200Mbit/s shield interface
  • One 1Gbit/s shield interface
  • Not hot pluggable Triple HDMI Output Shield


Each port can deliver an independent 1080p60 4:4:4 stream with a different set of image processing nodes applied. Typically there will be one complete image processing pipeline and the three HDMI ports will output the real time image data from specific points in that processing pipeline. Dual Micro SD Shield

This module adds two micro SD card slots to the AXIOM Beta. The active slot can be switched via the card driver and both cards share a 50MByte/s interface to the Zynq.

The bandwidth is not sufficient for video recording but more than enough for storing full resolution 4K raw still images.

The external slots can not be used for initial booting of the camera.

I2.png I.png
PCB Top PCB Bottom

2.7.4 Modules

There are also 2 high speed IO interfaces where "modules" can be hot plugged

  • 6.2Gbit/s each:
    • 6 ✕ 950Mbit/s
    • 500MBit/s GPIO
  • Two modules can be combined in one 12.4 Gbit/s double height module
  • Hot pluggable
  • PCIe connector (not using PCIe signaling)