SPA-3 is a Takahashi FSQ-106EDX4 (106 mm) F3.6 telescope, situated in IC Astronomy Observatory, Spain. It is equipped with a set of Astrodon astrophotography and it is an excellent choice for wide field of view astrophotography of deep sky objects.
- 1.5 credits/min or 90 credits/hr
- Model: Takahashi FSQ-106EDX4
- Aperture: 106 mm
- Focal Length: 382 mm
- F-ratio: 3.6 (with 0.73x focal reducer)
- Mount: Paramount MX+
- Minimum elevation: 30 degrees
- Model: FLI PL16083 (spec sheet)
- Pixel Size: 9 μm
- Pixel Array: 4096 x 4096
- Pixel Resolution: 4.74 arcsec/pixel
- Cooling: -25 degrees in Summer, -30 in Winter
- Field of View: 324 x 324 arcmin (but see Image vignetting)
- Filters (50mm square): Astrodon LRGB 2GEN, Ha (3nm), SII (3nm), OIII (3nm)
- Position angle: [TBC]
- Allowed exposure times (in seconds): 5, 10, 15, 20, 30, 45, 60, 90, 120, 180, 240, 300
- Automated calibration: Yes, the images will be provided fully calibrated in FITS format
- RBI correction enabled: Yes
- Active guiding: Yes, external
- External scope: Takahashi FS-60C
- Guiding camera: Starlight Xpress Ultrastar
- Initial set up, including focusing and target centring: 6 min
- Image overhead (readout, download, plate solution):
- For binning 1: 45 sec
- Change filter: 15 sec
- Refocusing: 6 min
- New sets of calibration frames are acquired every week
- Flat field frames for each filter are acquired using an Alnitak Flip-Flat Flat Fielder
- Darks are acquired for each allowed exposure time
- Site: IC Astronomy
- Location: Oria, Almería, Spain
- Coordinates: 37.4988 N,-2.42178 W (Google maps)
- Elevation: 1250 m
- Average seeing: 1.5'' - 2.5''
- MPC code: [AWAITING] read more
The images obtained with SPA-1 and SPA-3 suffer from vignetting caused by the image circle of the telescope. The diagonal of the CCD chip of 52mm is in fact larger than the projected field of view of the telescope, nominally of 44 mm at 60% illumination.
While some signal is still present at the extreme corners of the image, flat fielding alone is not sufficient to completely eliminate the problem, which should be corrected in post-production.
While we could crop the image for you, we prefer to deliver the image in its full size and leave the decision to you.
Note that we will not issue refunds if the given reason is for this image vignetting.