INT Wide Field Camera

Device Identification

Mosaic name                              INT WFC

Year of manufacture                  1998

Serial numbers                           CCD1  A5506-4,   CCD2  A5383-17-7,   CCD3  A5530-3,   CCD4  A5382-1-7

First Light on La Palma       April 1998

Description                                 The INT Wide Field camera is a 4 Chip Mosaic of thinned AR coated EEV 4K x 2K devices.

                                                    Now running with ULTRADAS, these figures are correct as I write 3rd Nov.1999 but are likely to improve.

Operational Characteristics

Only one readout speed at present. Readout time 37s + processing 11s + writing to disk 8s = total 56s
 

CCD
Noise(e)
Gain(e/ADU)
Bias
1
7.8
2.8
1527
2
9.2
2.8
1590
3
7.7
2.4
1623
4
7.8
2.8
1644

Physical Characteristics

Pixel Scale                                                            0.333 arcsec/pixel

Field of view                                                         34 x 34 arcmin

Pixel Size                                                              13.5 microns x 13.5 microns

X size of digitised area in pixels (each ccd)          2148

Y size of digitised area in pixels (each ccd)          4128

X size of useful imaging area ( each ccd )             2048

Y size of useful imaging area ( each ccd )             4100

X start of useful imaging area ( each ccd )            50

Y start of useful imaging area ( each ccd )            0

LN2 capacity of cryostat                                                6 litres

Cryostat window thickness and distance of chips from window.

Details of gaps between image areas of mosaic elements.

Operational Parameters

Operating temperature                                                 -153K

Preferred amplifier - all CCDs have 2 working amplifiers, however, CCD1 shows very poor HCTE when using right hand amp. so all 4 EEVs are read out using the left hand amp. (28/4/98)

Anti-blooming - this is available and removes or reduces the effects of saturated stars blooming up and down a column, it can only be en/disabled by the duty engineer. ( block 18 of ram-disk )

Measured Characteristics

Quantum Efficiency ( @-120C )
 
 

Wavelength
380nm
400nm
650nm
950nm
CCD1
67
80
75
13
CCD2
72
87
79
15
CCD3
62
80
80
14
CCD4
61
78
86
16


Full QE curve for EEV4280 in tabulated measured at ATC March 99
 

Dark Current

Measured in electrons per pixel per hour
 
 

CCD1 
CCD2 
CCD3 
CCD4 
-110 Centigrade 
3.8 
3.3 
2.9 
2 
-120 Centigrade 
0.5 
0.7 
0.3 
0.5 
Fringing                                5% in 'I' , 20% in 'Z'

Full Well Bloom Limit                  200000e

Chip flatness and Co-planarity

Individual EEV CCDs have a convex bow of between 6 and 10 microns. The mosaic co-planarity is within +/-20um. It is recommended that when focusing the camera, stellar images should be optimally focused at the three points :


Pretty Pictures

M101M13M8M81

M42 the prettiest of all. Courtesy of Nik Syzmanek.
 

This page last updated : 28th February2000
awr@ing.iac.es