You only need to read these instructions if you have our BASLER CMOS camera.
If you have the high resolution CCD option, you need these instructions instead.
If you have the Macro camera, you need these instructions instead.
If you have the 1CCD Laue camera, you need these instructions instead.
If you have the 2CCD Laue camera, you need these instructions instead.
If you have a standard video camera, you need these instructions instead.
These instructions are for Windows-10; for other versions they may be slightly different.

The BASLER Ace CMOS Camera

NeutronOptics x-ray or neutron cameras can be supplied with an optional BASLER Ace IMX249 CMOS Camera when high frame rates are required (up to 41 fps). The normal maximum exposure of the IMX249 camera is 10 seconds; dark current noise is higher for CMOS cameras, limiting them to shorter exposures, but these times can be increased using SharpCap (below).

The IMX249 is a slower frame-rate version of the IMX174, currently the best Sony CMOS detector for low-light imaging. It is a relatively large sensor, with big pixels favouring light capture, with high Quantum Efficiency (QE) The USB3 camera is powered by a USB cable up to 25m long, and the GigE version by a powered GigE cable. Note the optional cooling fins added to the camera to limit temperature (and dark current) by air cooling, and the carbon fibre window for the x-ray version.

  • Sensor Type: Sony Pregius CMOS IMX249
  • Image size: Diagonal 13 mm (Type 1/1.2")
  • Resolution: 1920 x 1200
  • Pixel Size: 5.86 x 5.86 µm
  • High sensitivity: (QE~80% at 500-600nm)
  • High dark current: (~1 e/s @ 45C)
  • Full well capacity: >30,000 e- (high dynamic range)
  • ADC: 12 bit grey scale, stretched to 16-bit
  • Gain: 0 dB to 29.9 dB
  • Readout Noise: ~7 e- (low readout noise in mode_7)
  • Readout Time: ~0.025s (up to 41 fps full frame rates)*
  • Interface: USB 3.1 High Speed with 5-15m USB cables
                     or PoE GigE ethernet for long distances
  • Power: power over USB (or Ethernet)
  • Maximum Exposure Length: 4s USB3, 32s GigE
  • SDK: BASLER Pylon C++ SDK
* Very high frame rates (41 fps) are only possible with short USB3 cables (5m).
But rates of 9 fps can be obtained even with 10+ metre amplified USB2 extension cables.

Install Pylon6.1.1 with the Basler Camera Driver

  • Download the pylon 6.1.1 Camera Software Suite for Windows (or other systems).
    Click on the installer and choose the "Developer" option then "USB" and/or "GigE".
    More recent versions than 6.1.1 are not compatible with the SharpCap viewer.
  • Installing the Pylon Viewer also installs camera drivers for USB and/or GigE cameras

BASLER Pylon Viewer for Camera Control

The Pylon Viewer was designed for high frame rate and video capture in daylight and contains additional features you won't need for slower x-ray or neutron imaging. The camera will be automatically recognised when plugged in (Pylon is designed to control multiple cameras simultaneously). A window will open displaying windows for devices and features; more windows are available under the "Window" menu. Double-click on the camera in the "Devices" window and set its properties in the "Features" window. Click on the video (fourth) icon in the header to start a stream of images. (Click the image to enlarge it).

Prefer the "Features-Basic" window (below), which contains all that you will need except possibly "Binning". In particular you can change the region of interest "Width" and "Height", the pixel format (Mono12 packed is best or Mono8 for maximum frame rate), and most importantly the "Exposure Time" (in mcroseconds). Using "Gain" will increase image brightness, but reduce" signal/noise ratio. The icons along the top of the Pylon window represent "On", "Save", Image", "Video" "Stop", "Pause" "Record", "Magnify", "De-magnify" etc. The Cross arrows display the full image, and the remaining icons add a crosshair or target, display the intensity histogram etc. Hover over the icons for details. These actions are also available from the menu. (Click the images to enlarge them).

The sample image is of a 50 micron grid from our macro camera. Of the other features, you can only apply “binning” to increase intensity at the expense of resolution if you have a GigE camera, but you can do binning off-line in imageJ. Binning of 2x2 is recommended with this high resolution detector. You might want to invert the axes for a "Mirror Image".

You can create your own "Features" list by editing the "Features-All" window. Probably you will want to add "binning" to the "Features-Basic" list. Note that Exposures are limited to 1000000 micro-seconds (10s) by Pylon, but can go to 5 minutes using SharpCap, and noise, including amplifier glow, is still reasonably low after ImageJ filtering.

Alternative SharpCap Viewer

Instead of Pylon, you can also use SharpCap4, which was designed for low-light imaging by amateur astronomers, with more complete controls, including many you will not need for x-ray or neutron imaging. Prefer the 32-bit version for compatibility, and please observe the licencing agreement if you install it. You must first install and run Pylon6.1.1 (above) to install the drivers and eventually set binning with the GigE camera. The camera will be automatically recognised if it is plugged in, and you just need to choose it from the “Cameras” menu. A window will open with the image and camera controls on the right. You can arrange the order of controls by dragging the 3-line icon. An exhaustive SharpCap User Manual is available, but the instructions below may be sufficient to start with. (Click the image to enlarge it).

In the "Camera Controls", choose 12-bit and you set the Exposure (toggle LX mode for long exposures), set a high Gain to increase efficiency (at the expense of noise). In the "Capture Format", select TIFF or FITS and Mono16. In menu "File/Settings" turn off "Auto Output Format" and set the "Default Zoom" to fill your screen. The top rightmost icon allows you to use Edge Detection and other focussing aids. You can drag the vertical line in the "Display Histogram" to stretch the intensity display to emphasise the lower intensities (and see the noise). Tip: set a "Default Profile" and the camera will be opened with those settings when SharpCap starts.

Stacking short exposures in SharpCap 3.2 and 4.0

An interesting feature of SharpCap is real-time stacking of a series of short exposures. This allows you to judge when you have sufficient intensity (and to overcome the maximum exposure limit of the camera). Click on the "Live Stack" icon above the image display to open this stacking window. You can drag this window so that it does not cover the image. Switch off "Align Frames" which refers to alignment based on stars. Most of the controls to the right are also for astronomers; only the live histogram is useful, but normally you might save the summed stack as a 32-bit image and filter noise from it with imageJ.

You can also use imageJ to stack a series of short exposures, which allows filtering of noise from the individual images before averaging. For very short exposures this may be better than averaging first and then filtering. Use the SharpCap menu Capture/Start_Capture then enter the number of images to be saved. After capturing those images, use the ImageJ menu File/Import/Image_Sequence, open the first image, and then OK to import all images in that directory into a displayed stack. Use Image/Adjust/Brightness-Contrast to examine the noise, and apply Process/Noise/De-speckle to all images. You may need to De-speckle twice. Finally sum or average the stack using Image/Stacks/Z-Projection.

For long stacked exposures you may see a diffuse background patch due to amplifier glow.
Depending on the speed of your computer, frames may be dropped for frame rates >8 fps.

FireCapture Imaging Software

FireCapture is another image capture application developed for amature astronomy that you might also use for neutron and x-ray imaging with our cameras.

Hints on getting Optimal Images

  • The center of the image may not correspond to the centre of the window
    because the CCD chip is not centred to better than 0.5mm in its housing
  • The exposure time depends of course on the intensity of your beam
  • Exposure time and frame rate can be controlled separately for short exposures
  • Use "Process/Noise/De-speckle" in ImageJ to remove noisy pixels from saved files
A PDF version of these instructions is available.