- About WIYN
- Observing at WIYN
At the Telescope
- Internal Use
ONE DEGREE IMAGER (ODI)
The One Degree Imager (ODI) is the flagship of WIYN's new instrument initiatives. ODI will utilize both WIYN's one degree field of view and excellent image quality. The focal plane of the optical imager will be sampled with 0.1" pixels, or 1 Gigapixels in total. The sharpness of images will be actively improved by correcting images for tip/tilt image motion during the integration corrections will be done over the entire field of view, using a novel detector technology called Orthogonal Transfer Array CCD, making ODI a unique and competitive instrument in the era of wide-field surveys. ODI is funded by the WIYN partners and the National Science Foundation.
pODI (ODI with a partially populated focal plane) is currently in operation at WIYN. Nine OTAs comprise the central observing area, subtending an area of approximately 25 arcminutes on a side. Four outlier OTAs are available for guiding.
Telescope WIYN 3.5m Telescope Port Permanently mounted at f/6.3 Nasmyth port
Field of View 1° x 1° square; 1° diameter circle unvignetted; useful science FOV for partially filled = 24' x 24' Pixel Scale 0.11 arsec/pixel Detectors (partial focal plane) 13 Orthogonal Transfer Array CCDs. Each OTA CCD comprises 64 480x496 pixel cells; pixels are 12μ square Readout Noise 6 - 10e- Gaps between detector cells 3" in x direction
1.2" in y direction
Filling factor of each OTA 93% Filling factor of focal plane 84% (for full focal plane with all operating cells) Partially filled focal plate of ODI with the location of 13 OTAs depicted.
[North is up, East is left]
QE curve of the OTA CCDs
Initial Filter Set g',r',i',z' (full size)
Filters from NOAO CCD Mosaic Imagers (in adapter)
Filters size 42cm, 42cm Number of filter slots 9
Readout Time 30 seconds
File Size (full focal plane) 2GB/image uncompressed
(partial focal plane) 200MB/image uncompressed
File Format Each focal plane readout produces a directory in which data from each OTA is contained in a 64-extension MEF file.
Active image quality improvement On-chip image motion correction (experimental)
Atmospheric dispersion compensator
Guide Modes Static Imaging - no OT shifting; detectors are operated like CCDs
Coherent Guiding - Identical OT shifting of all cells
PIPELINE, PORTAL, AND ARCHIVE
All ODI data will be transferred to the ODI PPA system at Indiana University. It will be pipeline processed to remove instrumental signature, and archived. Raw and reduced data may be downloaded from the archive by PI's and Co-I's during the proprietary period and by anyone after the period ends. Proprietary period 18 months (default)
Last modified: 20-Jul-2015 15:39:55 MST
- Observing at WIYN