1,900 bytes added,
05:55, 11 March 2019
Combined Sprat/SHOC is way to go.
Working out from Nasmyth:
* "Inside" Nasymyth is autoguider. This can patrol half of the field of view, and will hopefully have a focus mechanism.
* Nasmyth mounting:
** James to provide details of this mounting as used on Wide Field Camera on opposite port.
** 1/4 of the field of view will be for a High Resolution Spectrograph (HRS) fibre feed
** 1/4 of the field of view with be for SPRAT/SHOC
** A cable wrap (copy of that on opposite port) will be provided. James to provide details.
** There is possibility of pneumatic supply
* Deployable calibration mirror (to feed flat/arc)
* Deployable slit
* Field Lens
* Collimator Lens
* FILTER SLIDES (3). Hopefully <50mm thickness. To house maybe 5 filters each. Note one filter will need to be order blocker (4000-8000 Angstroms) for SPRAT. James to design to fit to an interface in SPRAT.
* Grism Assembly
* Camera Lens and CCD.
General Design Points
* Filter slides need to be in collimated beam to avoid focus shifts
* Try and minimise cables on/off mount. So mount control computer with instrument. Note SHOC software requires GPS feed (serial; currently using serial to USB, Amanda to check latest GPS hardware).
* USB for camera rather than PCI Card
* Use existing SHOC CCD readout (via andor SDK)
* Use existing Apache Thrift infrastructure
* LJMU responsible for all mechanism control, including filter slides
* Use wiki to keep one version of documentation/files etc.
Actions:
* IAS: Check/modify optical design to make space for filter slides
* James: Provide details of mounting plate/wider field camera (STEP File); provide information on cable wrap being used on other port
* Carel: Provide details of SHOC software to Chris Mottram so he can try and built a local copy at LJMU
* Amanda: Look at trade off between deep depletion (higher red QE, higher dark current) and standard EMCCD