Proton Calorimetry/Experimental Runs/2018/JanMarPlans: Difference between revisions

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*Think of possible measurements to do energy calibration for the sheets. Simulation shows 15% variation of light emission in first 100mm of scintillator
*Think of possible measurements to do energy calibration for the sheets. Simulation shows 15% variation of light emission in first 100mm of scintillator


=== ISDI sensor: <span style="color:red">'''Simon, Laurent, Anastasia, Derek'''</span> ===
=== ISDI sensor: <span style="color:red">'''Laurent'''</span> ===


Harware we need to buy:
Hardware we need to buy:
* We definitely need:
* We definitely need:
**A camera link cable, MDR male to male. Maximum 10m. Found it on RS components: https://uk.rs-online.com/web/p/parallel-cable-assemblies/3246833/
**A camera link cable, MDR male to male. Maximum 10m. Found it on RS components: https://uk.rs-online.com/web/p/parallel-cable-assemblies/3246833/
**a power supply: MDS-060AAS24 BA
**A power supply: MDS-060AAS24 BA
**A USB to JTAG cable to access the FPGA on the board
**A USB to JTAG cable to access the FPGA on the board


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**frame grabber card "epix" PIXCI(R) E4
**frame grabber card "epix" PIXCI(R) E4
**Aspect software (Yiannis from ISDI will write Simon an email if we have to buy the license of if we can just have it). The aspect software comes with an epix driver. Once we order the software from ISDI it should arrive within 2 working days.
**Aspect software (Yiannis from ISDI will write Simon an email if we have to buy the license of if we can just have it). The aspect software comes with an epix driver. Once we order the software from ISDI it should arrive within 2 working days.
**LabView for the Aspect software. Can be downloaded from ucl software database: http://swdb.ucl.ac.uk/package/view/id/218?filter=labview


==== Progress ====
==== Progress ====
* ISDI sensor brought to UCL
* ISDI sensor with fibre optical plate brought to UCL
* What has been bought/ordered:
* What has been bought/ordered:
**A power supply: MDS-060AAS24 BA — Ordered an equivalent from RS.
**A power supply: MDS-060AAS24 BA — Ordered an equivalent from RS.
Line 397: Line 398:
==== To do ====
==== To do ====
* Decide for one data acquisition option: Pleora converter or frame grabber
* Decide for one data acquisition option: Pleora converter or frame grabber
* Buy all necessary hardware
* Buy all necessary items:
* Build bridge to protect mini wires on sensor
**Pleora option:
* Build something to hold sensor stable on topp of the scintillator stack
***Pleora camera link to USB3 adapter: PN903-0007. Lead time about 4 weeks
* Test sensor with LED
***USB3 cable. max 5m. We already have one, but it would be better to have one with fixation screws. Laurent couldn't find one on the internet yet though.
***MCL cable: male SDR and female MDR connector. max 10m. See here: http://www.epixinc.com/products/cables_cl.htm#cable_length Get it from here: http://www.epixinc.com/epix/ordering.htm (lead time unknown yet but probably similar to frame grabber (2 weeks))
**Frame grabber option:
***Aspect software. Order from Yannis (ISDI). Lead time about 2 days
* Ask Derek to build bridge to protect mini wires on sensor
* Talk to Derek in order to build something to hold sensor stable on top of the scintillator stack
* Mount ISDI sensor on top of scintillator stack. Set up one of the read out options (pleora or frame grabber).
**Pleora: Connect sensor to the power supply. Connect sensor to the pleora cameralink to USB3 converter using the camera link MCL male to male cable and the male SDR to female MDR connector. Connect the pleora converter to the DAQ laptop using a USB cable. Start ebus software from pleora.
**Frame grabber: Connect sensor to the power supply. Connect sensor to the PC with  using the camera link MCL male to male cable. Start aspect software on the PC.
* Test sensor:
**Familiarize with readout system, measure dark noise, check for inactive pixels and columns
**With LED: Test the dynamic range, check if end of fake Bragg peak can be seen, determine of full well mode oder half full well mode is more appropriate, measure gradient if one single sheet is illuminated with LED.

Revision as of 10:53, 19 February 2018

Proton Therapy Range Telescope Plan of Action January–March 2018

Diary

January

  • 22nd–29th Jan: Set up Nikon DSLR camera image acquisition — Laurent.
  • 25th Jan: Painting of scintillator sheets — Anastasia (with Derek).
  • 29th Jan–2nd Feb:
    • Confirm alternative sensor options — Anastasia.
    • Retest painted scintillators to check for light deterioration — Anastasia.
    • Construct light cone for light injection tests — Anastasia. Done.
    • Set up Nikon DSLR camera remote image acquisition — Laurent.
    • Mount Nikon DSLR camera to enclosure breadboard — Laurent.
    • Enclosure assembly begins for both enclosures — Simon.
  • 31st Jan:
    • First draft of paper circulated — Anastasia.
    • Measure scintillator thickness after painting — Dan, Jordan.

February

  • 5th–9th Feb:
    • Set up sensor readout — Anastasia, Laurent.
    • Testing of sensors and camera begins — Anastasia, Laurent.
    • Enclosure assembly complete for both enclosures — Simon (with Derek).
  • 10th Feb: Optimal submission deadline for paper (before Ruben and Anastasia go away) — Anastasia.
  • 12th–16th Feb:
    • Construct mechanical support for sensor, assemble in enclosure — Anastasia, Laurent.
    • Testing of sensors and camera within enclosure begins — Anastasia, Laurent.
  • 14th Feb: Second draft of paper circulated — Anastasia.
  • 19th–23rd Feb: Complete testing of sensors and camera within enclosure at UCL — Anastasia, Laurent.
  • 28th February: Submission deadline for paper — Anastasia.

March

  • 8th–9th March: Birmingham test beam.
  • 21st–24th March: MedAustron test beam.

April

  • 19th April: Clatterbridge test beam.

Tasks

Anastasia

  • 25th Jan: Painting of scintillator sheets (with Derek).
  • 29th Jan–2nd Feb:
    • Confirm alternative sensor options.
    • Retest painted scintillators to check for light deterioration.
    • Construct light cone for light injection tests.
  • 31st Jan:
    • First draft of paper circulated.
    • Measure scintillator thickness after painting (with Dan, Jordan).
  • 5th–9th Feb: Set up sensor readout.
  • 10th Feb: Optimal submission deadline for paper (before Ruben and Anastasia go away).
  • 12th–16th Feb:
    • Construct mechanical support for sensor, assemble in enclosure.
    • Testing of sensors and camera within enclosure begins.
  • 14th Feb: Second draft of paper circulated.
  • 19th–23rd Feb: Complete testing of sensors and camera within enclosure at UCL.
  • 28th Feb: Submission deadline for paper.

Laurent

  • 22nd–29th Jan: Set up Nikon DSLR camera image acquisition.
  • 29th Jan–2nd Feb:
    • Set up Nikon DSLR camera remote image acquisition.
    • Mount Nikon DSLR camera to enclosure breadboard.
  • 5th–9th Feb: Set up sensor readout.
  • 12th–16th Feb:
    • Construct mechanical support for sensor, assemble in enclosure.
    • Testing of sensors and camera within enclosure begins.
  • 19th–23rd Feb: Complete testing of sensors and camera within enclosure at UCL.

Simon

  • Confirm dates of beam tests ASAP.
  • 29th Jan–2nd Feb: Enclosure assembly begins for both enclosures (with Derek).
  • 5th–9th Feb: Enclosure assembly complete for both enclosures (with Derek).

Test Beams

Birmingham: 8–9th March

  • Preliminary beam tests at 28–36 MeV.
  • Check experimental setup, DAQ in test environment.
  • Run with both DSLR and pixel sensor in single enclosure: compare output.
  • Check isolation and crosstalk from both DSLR and sensor.
  • Check light output levels and corresponding exposure times for DSLR and sensor.
  • Preliminary test of radiation hardness: monitor radiation dose to sheets.
  • Run tests with both 3 mm sheets and 2 mm sheets but don’t intermingle (no need):
    • Quick test with best 2 mm sheets (save for Clatterbridge).
    • Longer test with 2.6 mm/3 mm sheets to check variation in light output with radiation dose and light levels from sheets.
  • Possibly observe quenching effects for different intensities:
    • Might see nothing as intensity variation comes from different collimators, so dose doesn’t change, just takes up larger volume.
  • Can we see a Bragg peak? Can Laurent reconstruct it? Observe position in Bragg peak with energy variation.
  • Hardware requirements:
    • Light tight enclosure with base for mounting: Zarges case with Thorlabs breadboard installed.
    • Patch panel for cable I/O: DSLR power and USB; pixel sensor power, USB and cameralink.
    • DSLR and associated cabling and software.
    • Pixel sensor and associated cabling and software.
    • All scintillator sheets with 2 bare sides.
    • Vice for holding scintillator.
    • Laptop running remote desktop for camera/sensor acquisition.
    • Network hub and 15 m cable to connect to laptop.
  • Simon to confirm dates with Tony Price.

MedAustron: 21st–24th March

  • Repeat measurements from Clatterbridge up to 100 MeV.
  • Energy limited by 85 mm vice capacity: can we purchase larger vice beforehand?
  • Vary energy from 100 MeV downwards and reconstruct Bragg peak position: repeat 60 MeV measurement (will be 62 MeV but close…).
  • Calibrate scintillator light output:
    • Use 252 MeV beam with absorber behind scintillator stack.
    • Record light output with beam scanned across multiple positions.
    • Carry out calibration on first night.
  • Monitor radiation damage light output and quenching.
  • Make single module measurements for MedAustron to monitor very low rate extraction: only if more than 1 shift available.
  • Hardware requirements for range calorimeter:
    • Light tight enclosure with base for mounting: smaller Peli case with Thorlabs breadboard installed.
    • Mounting hardware to MedAustron couch.
    • Patch panel for cable I/O: sensor USB, power and cameralink.
    • Pixel sensor and associated cabling and software.
    • All scintillator sheets with 1 bare side.
    • Vice for holding scintillator.
    • Laptop running remote desktop for camera/sensor acquisition.
    • Network hub and 20 m cable to connect to laptop.
    • Absorber behind scintillator stack?
  • Hardware requirements for single module:
    • Light tight enclosure with base for mounting: repurpose Zarges case.
    • Mounting hardware to MedAustron couch.
    • Patch panel for cable I/O: needs signal and BNC HV.
    • LeCroy scope plus Caen digitiser.
    • Caen portable HV.
    • PMT and scintillator for 252 MeV.
    • Long BNC and HV cables in case we want to run with the scope outside the treatment room.
    • Scope running in mode to monitor trigger rate.
  • Simon to confirm dates with Claus Schmitzer.

Clatterbridge: 19th April

  • Beam test at 60MeV clinical energy: target of grant.
  • Primary tests at 60 MeV with variation down using wheel modulator.
  • Reconstruct peak at 60 MeV.
  • Observe changes in Bragg peak depth and whether there is any change in the shape of the peak.
  • Observe variations in light output and peak shape with beam intensity:
    • Use cyclotron source to vary intensity, so changing dose.
    • Monitor radiation hardness and quenching.
  • Make a measurement at 60 MeV at clinical rate with 3 different groups of sheets.
  • Refine acquisition parameters for clinical rate for sensor and DSLR.
  • Hardware requirements: identical setup to Birmingham but longer network cable required.
  • Simon to confirm dates with Andrzej Kacperek.

Task List

Single module paper: Anastasia

  • First full draft circulated by 31st January.
  • Second draft circulated by 14th February (or sooner if main corrections are only wording etc. rather than content and plots).
  • Submit to journal by 28th February.
  • Ideal submission by 10th February (before Ruben goes away).

Sensor selection and readout: Anastasia, Laurent

  • PRIAPUS sensor used for previous tests has several drawbacks:
    • Large enclosure that is mechanically difficult to fix in confined space.
    • Bare sensor that is difficult to couple to.
    • Sensor requires a pair of cameralink cables with bespoke PCI card.
    • Assembly likely too large to ship to MedAustron.
  • ISDI can provide range of commercial sensors:
    • Best options 5 x 10 cm and 15 x 10 cm: the latter probably suits our purposes.
    • Meeting on 25th January with Simon and Laurent at ISDI in Kentish Town: very promising options.
    • ISDI will provide details of all sensor options and readout methods: Laurent will liaise with them and look after sensor assembly, readout, DAQ and cabling.
  • Alternative possibilities still need pursuing:
    • Hamamatsu.
    • Teledyne Dalsa.
    • Varex.
    • Rayence.
    • Anastasia will chase up during week of 29th January.
  • Coupling via Fibre Optic Plate (FOP) to scintillator:
    • ISDI provide FOP already glued to sensor.
    • Unclear whether alternative manufacturers can provide similar.
  • Sensor needs to be read out using laptop connected via remote desktop: Anastasia and Laurent set up sensor readout week of 5th February.
  • Mechanical structure to support sensor within enclosure:
    • Anastasia and Laurent to liaise with Derek.
    • Begin assembly week of 12th February: will depend on arrival of sensor.

Progress

  • Communication with ISDI to purchase sensor.
    • Laurent to go to ISDI on Friday 16th of February for software training and to pick up the sensor
    • Awaiting invoice and information to set ISDI up on the system on Friday the 9th of Februray
  • ISDI provided more details on sensor requirements:

To Do

  • Set up ISDI on the system
  • Maintain contact with Hamamatsu regarding linear image sensors
  • Chase up alternative sensor providers once more time becomes available (unless there are problems with ISDI, in which case urgency needs to be stepped up):
    • Teledyne Dalsa
    • Varex
    • Rayence

Nikon DSLR and readout: Laurent

  • Nikon D70 DSLR borrowed from Adam Gibson in Medical Physics.
  • Camera used as corroborative image with sensor.
  • Mounted in same enclosure viewing scintillator at 90 degrees.
  • Powered by mains with proprietary Nikon connector: battery doesn’t work.
  • Controlled via USB using open source software.
  • Laurent to set up software and acquire images week of 22nd January.
  • Laurent to set up camera for remote acquisition week of 29th January.
  • Camera needs mounting into enclosure to optical breadboard.
  • Laurent to mount camera and check mechanical setup week of 29th January.

Progress

  • 40mm macro lens ordered from WEX Photographic.
  • Battery charger ordered from both WEX and supplied by Adam Gibson...
  • Patch panel connector and USB cables delivered from RS.
  • Rubber grommets available from Derek for feeding DSRL PSU into enclosures.
  • Remote control of camera working fine
  • Remote control of DAQ laptop working fine
  • USB 2&3 cables and patch panel connectors tested: working fine
  • 40mm macro lens tested: image is indeed bigger and covers nearly all of the scintillator stack

Scintillator sheets drilling holes: Anastasia

  • In order to carry out tests at UCL we want to be able to inject light into the scintillator sheets.
  • We want to be able to measure all 30 sheets at once, this could be useful. Therefore:
    • Construct a light cone (like the one used for SuperNEMO in dark cupboard in D27) to distribute one LED to 30 optical fibres so that all sheets can have an LED input.  Should take 2-3 days to construct. Week of 29th January or later, depending on whether we need to. Anastasia (with Derek).  Note: currently we are able to measure two at a time in a “portable” scenario using light cone constructed previously by Derek and myself.
    • OR
    • Use the current light cone in the dark cupboard in D27 for tests at UCL – should take 1 day to set up – Anastasia, week of 5th February.
  • If we want to be able to bring the LED with us for emergency tests at test beams, on the patch panel that will be made up for the flight case remember to include a hole large enough to fit 30 fibres through, with an option of a "shutter" to make the case light tight when not testing with an LED. Remember we already have a light cone we can bring with us so we should put at least one optical fibre connector on the patch panel.
  • Drill holes in 2 mm sheets – I have checked with Derek and this can be done on the thin scintillators, with care.  The drilling must be done before painting, then the hole can be masked off during painting.  Thursday 25th January –Anastasia (with Derek).

Progress

  • All scintillator sheets have been drilled (Derek).
    • Testing of the scintillators has begun (see "Testing at UCL" section for details).
  • The light cone has been constructed with 64 fibres (Derek).
    • Tests have begun using the light cone, which works well but with uneven distribution of light throughout the cone.
  • List completed.

Scintillator sheets painting: Anastasia

  • Three types of paint currently being tested:
    • Chalkboard paint (painted on 08/01/18) – scintillator looks healthy!
    • Halfords Satin Black aerosol paint (painted on 12/01/18) – scintillator looks healthy!
    • Model paint (painted on 12/01/18) – scintillator looks healthy!
  • Halfords satin black spray chosen for scintillators: so far no bad effects seen on the scintillator. An original NUVIA 3mm enhanced scintillator sheet has been tested before and after spraying and everything looks good.
    • Anastasia to test again towards the end of the week of 29th January/beginning of 5th February to make sure light collection hasn’t deteriorated.
  • Painting of new sheets to be started on Monday 29th January – estimate around 1-2 days, depending on fumes in the room etc., to complete: Anastasia (with Derek).
  • Scintillator sheet thickness should be ready to be re-measured by Dan and Jordan on Wednesday 31st January. 


Progress

  • All sheets have been spray painted (Derek).
  • The thickness of all sheets has been measured before and after painting to check for uniformity of thickness from the manufacturing process and the extra thickness added by the paint (Jordan and Dan).
  • "Novus 2 Fine Scratch Remover" polish for scintillator polishing has been purchased.
  • Original spray painted sheet retested 16 days after first tests and there is no light degradation seen.
  • Two painted sides have been repainted (Derek). They are light-tight now.
  • Sheet number and thickness on each of the sides has been marked with white paint marker.

To Do

  • Polish out scratches on the sides of the scintillator that will be read out by sensors.

Detector enclosures and flight cases: Simon

  • Derek has purchased and modified a vice to hold a scintillator stack of up to 85 mm.
  • Four flight cases purchased by Simon.
  • Optical plate for base of both enclosures needs to be ordered.
  • Construct case and mount setup week of 29th January and 5th February – talk about design 
and what needs to be in the case (connector types on patch panels etc.) once sensor is decided.
  • Order patch panel connectors and cut window for beam entrance.
  • Full assembly ready by 9th February. 

  • Simon will liaise with Derek regarding construction of enclosures.

Progress

  • 3 waterproof and wheeled flight cases ordered and delivered from RS:
    • Large Zarges case for single module setup: 800x500x385mm
    • Medium Zarges case for range calorimeter tests: 600x400x386mm
    • Small Peli case for carrying range calorimeter in hand luggage without Nikon DSLR: 230 x 555 x 350mm
    • 4th Peli case ordered for carrying equipment.
  • Zarges cases painted black and ready for patch panel installation (Derek).
  • Thorlabs optical breadboards ordered for each case and cut down to size (Derek).
  • Patch panel connectors for single module case arrived:
    • Huber and Suhner SMA.
    • BNC signal.
    • We already have SHV connector.
  • Peli case prepared for fast treatment plan verification test (Derek):
    • Optical breadboard installed.
    • Patch panel connectors installed: 1xSHV, 1xBNC, 1xSMA.
    • Hole cut for beam access.
  • DSLR camera mount recycled from tripod (thanks Spectrum!) (Derek).
  • DSLR cables for USB patch panel arrived from RS: USB male A to male A and USB male A to male mini B.

To Do

  • Install optical breadboards in flight cases (Derek).
  • Design mounts to allow Zarges cases to mount securely to MedAustron couch (Markus Stock has provided specs).
  • Cut and protect holes for beam entry:
    • Black out holes with paper/card/cloth/LX tape.
    • Protect hole with aluminium plate/flap.
  • Spec connectors for range calorimeter patch panel:
    • Sensor power (4-pin DIN?).
    • Sensor signal (USB2, USB3, Camera Link?).
    • Sensor trigger (SMA?).
    • DSLR power: mains plug (may not be necessary with new battery).
    • DSLR signal: USB2 (will USB3 work?).
  • Order remaining connector cables.
  • Cover for patch panel connectors.
  • Order larger wheels for both Zarges cases.
  • Spec and order DAQ SFF PC.

Testing at UCL: Laurent, Anastasia

  • Anticipate everything to be assembled by 9th February.
  • 10th–18th February Anastasia away: Laurent can start to carry out tests at UCL the week of the 12th February – we can go over how and what before that etc.
  • Continue tests (Anastasia and Laurent) during the week of the 19th February.  Tests to think 
about, with both the acquired sensor and the DSLR camera:
    • Light injection into each scintillator slice with clear record of the test setup (LED voltage and other pulser settings, sensor settings etc.) and the peak and sigma measured for each scintillator sheet.
    • This could be a test to help us see if there is any radiation damage after the stack has been in the test beams: compare values measured before and after test beam for the same settings.
    • 207Bi test if we have time – more details from Ruben.
    • Test of sensor “linearity”:
      • Scan across different LED voltages.
      • Take different frame times.
      • Test dynamic range of sensor.

Progress

  • Tests carried out with 3 mm sheets:
    • Measurements of all scintillator sheets injected with a fibre each and fibres switched around in subsequent measurements in order to confirm non-uniformity is seen due to fibres (and not scintillator)
    • Measurements of each scintillator sheet with the same optical fibre for crosstalk studies
    • Measurements of two fibres into two scintillator sheets for crosstalk studies
    • Measurements with LED settings the same as those used for PRIAPUS tests at UCL
    • Measurements of best settings for camera with PRIAPUS LED settings to not saturate the sensor
    • Measurements to determine dynamic range of sensor/saturation
    • Measurements with LED settings that saturated the PRIAPUS sensor to determine whether we can adjust camera settings to not saturate the camera
    • Measurements with 207Bi source
    • Measurements to determine the lens focus for the middle of the scintillator stack
  • Tests carried out with 2 mm sheets:
    • Measurements of all scintillator sheets injected with a fibre
    • Measurements of each scintillator sheet with the same optical fibre
    • Measurements with different focus: Focusing the front plane and the centre of the scintillator stack

To Do

  • With 2 or 3 mm sheets:
    • 207 Bi tests, including a background run
  • Think of possible measurements to do energy calibration for the sheets. Simulation shows 15% variation of light emission in first 100mm of scintillator

ISDI sensor: Laurent

Hardware we need to buy:

  • If we go for the Pleora camera link to USB3 adapter, we need:
    • Pleora camera link to USB3 adapter: PN903-0007
    • USB3 cable. max 5m. We already have one, but it would be better to have one with fixation screws. Laurent couldn't find one on the internet yet though.
    • MCL cable: male SDR and female MDR connector. max 10m. See here: http://www.epixinc.com/products/cables_cl.htm#cable_length Get it from here: http://www.epixinc.com/epix/ordering.htm (lead time unknown yet but probably same as frame grabber (2 weeks))
    • A computer with a USB3 port in order to get the full frame rate
  • If we go for the frame grabber we need:
    • PC (windows 7 is what ISDI uses) with camera link plug
    • frame grabber card "epix" PIXCI(R) E4
    • Aspect software (Yiannis from ISDI will write Simon an email if we have to buy the license of if we can just have it). The aspect software comes with an epix driver. Once we order the software from ISDI it should arrive within 2 working days.
    • LabView for the Aspect software. Can be downloaded from ucl software database: http://swdb.ucl.ac.uk/package/view/id/218?filter=labview

Progress

  • ISDI sensor with fibre optical plate brought to UCL
  • What has been bought/ordered:
    • A power supply: MDS-060AAS24 BA — Ordered an equivalent from RS.
    • A USB to JTAG cable to access the FPGA on the board — Ordered from RS.
    • frame grabber card "epix" PIXCI® E4 — Ordered the EPIX PIXCI E8: lead time 2 weeks.
    • PC (windows 7 is what ISDI uses) with camera link plug — PC ordered from Scan computing with 7 working day lead time; no native camera link connection: requires PCIe card (see above).
    • A computer with a USB3 port in order to get the full frame rate — We have the DAQ laptop and also the new PC

To do

  • Decide for one data acquisition option: Pleora converter or frame grabber
  • Buy all necessary items:
    • Pleora option:
    • Frame grabber option:
      • Aspect software. Order from Yannis (ISDI). Lead time about 2 days
  • Ask Derek to build bridge to protect mini wires on sensor
  • Talk to Derek in order to build something to hold sensor stable on top of the scintillator stack
  • Mount ISDI sensor on top of scintillator stack. Set up one of the read out options (pleora or frame grabber).
    • Pleora: Connect sensor to the power supply. Connect sensor to the pleora cameralink to USB3 converter using the camera link MCL male to male cable and the male SDR to female MDR connector. Connect the pleora converter to the DAQ laptop using a USB cable. Start ebus software from pleora.
    • Frame grabber: Connect sensor to the power supply. Connect sensor to the PC with using the camera link MCL male to male cable. Start aspect software on the PC.
  • Test sensor:
    • Familiarize with readout system, measure dark noise, check for inactive pixels and columns
    • With LED: Test the dynamic range, check if end of fake Bragg peak can be seen, determine of full well mode oder half full well mode is more appropriate, measure gradient if one single sheet is illuminated with LED.