Summary of meeting at the UKATC on 21/11/2000

Attendees

• David Atkinson.
• Vik Dhillon.
• Tully Peacocke.
• Mark Stevenson.

Optics

• Vik went through the requirements for the optics of ULTRACAM in order to confirm with Tully that the design met the requirements. Tully confirmed that the optics will provide:
  • a field of view of 5 arcminutes on a side (not diameter) on the WHT;
  • a pixel scale of 0.3 arcseconds (approximately);
  • image quality of two pixels or better;
  • a design which allows for an exchangable collimator. Tully emphasised, however, that the whole collimator (and not just the front element) will have to be exchanged for use on a telescope other than the WHT. This even applies to telescopes with the same focal length, because they may have different primary and secondary mirror types and hence different aberrations (the collimator takes these aberrations out).
  As for throughput, Tully stated that this depends on the coatings we can afford and the thicknesses of the lenses that the manufacturers specify, so it can't be predicted all that accurately at the moment. We will have a better idea of this when we have spoken to the manufacturers and received a quote.
• Vik described how he and Mark had looked into dichroic coatings briefly before the meeting and confirmed that the dichroics required in ULTRACAM definitely are feasible (in that there are a number of companies within the UK who can supply the coatings we require). Tully recommended that we find a substrate manufacturer for the dichroics first (or possibly include the provision of this with the other optics?) and then send the substrate to a specialist company for coating (such as Technical Optics on the Isle of Man - they did the ISIS dichroics). Tully will provide a list of companies.
  
  .....the rest of the minutes need to be typed up still.....

vsd, 07-february-2001