These pages are here to provide engineering information about the WYFFOS Long Camera project. This will be the fibre feed multi object spectrograph on the 4.2 Nasmyth platform.

WYFFOS Long Camera general information

The WYFFOS Long Camera is an enhancement on the existing WYFFOS spectrograph. The two advantages of having a larger chip in WYFFOS is that more of the slit area can be imaged (and so more fibres can be used) and more wavelength coverage at high dispersion can be obtain.

The old spectrograph with a focal length of 132mm and with a CCD (1024x1024 24µm pixels) was used together with AF2 and INTEGRAL. The imaged slit size is with the fibres giving an F/8.2 beam was 150mm.

The new extended WYFFOS Long Camera will have a focal length of 293mm and uses a Lincon Lab CCD (4096x4096 15µm pixels). With this the slit size that can be imaged is 168mm.

  WYFFOS

WYFFOS Long Camera
    Design Used (when commissioning)
Focal Length 132mm 293mm 293mm
Slit Size 150mm 168mm 150mm
Image area 24.5mm 58.6 x 57mm 55mm
Detector TEK 6 1Kx1K  24µm (24.5mm) MIT/LL 4Kx4K 15µm (61.4mm) EEV10a 2Kx4K 13.5µm (27.6x55.2mm)
Camera F# 1.05 132/(150-24.5) calculated 2.71 2.71
Vignetting 10% 28%  
       

WYFFOS Long Camera has not been commissioned yet but is planned to be end of 2004A.

Design

The new Long Camera part is made by ASTRON in the Netherlands. Documents can be found in the T&I group area or are on a backup CD with  the instrument manager.

The long camera for WYFFOS is based on the 239 mm BIGCAM3B. To fit the image of the slit assembly on a 4kx4k Lincoln Labs CCD chip (pixel size 15µm, 61.44x61.44 mm), the focal length of the camera had to be increased to 293 mm. The ZEMAX file of Richard Bingham's design was copied and served as a starting point for the design. The optical and mechanical layout from slit assembly to relay mirror in the ZEMAX prescription file of Richard Bingham was considered to be representative for the current WYFFOS instrument.