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get_noise1.pro


CCD (Charge Coupled Device) detectors are very important in the field of Astronomy and Electronic Imaging. The CCD alleviates the most difficult astronomical imaging problem of small, faint objects. It is important for general scientific work such as variable star monitoring and position determination.

The CCD based system has several advantages over film:
+ greater speed
+ quantitative accuracy
+ ability to increase contrast and subtract sky background with a few keystrokes
+ the ability to co-add multiple images without tedious dark room operations
+ wider spectral range
+ instant examination of the images at the telescope for quality.

Observations for June 10, 2003

Observer: Alla Shumko
Carsten Denker
Weather: Sunny, calm, warm
Seeing: 2 (chromospheric network, limb base visible)

Optical Setup for the 26-inch Reflector Telescope

West Center East
Filter Ha/Scanning Zeiss
Camera None None OSL
FOV None
Feature Active Region NOAA
Position W-E N-S



26-inch Reflector
20:58:00 Speckle observations
2nd setup 5.6/210 mm Componon-s 986 mm, 6302 A / 3 A IF filter 520 mm, Dalsa Dalstar 1M15 148 mm, FOV: 80 x 80, 6 ms, about 4000 counts, defocussed images by moving Componon-S lens 7 cm down the bench and added NG12 1 mm and NG11 1 mm
Target Active Region NOAA 10375 (695W 99N), 20 sequences, 1 minute cadence, best 100 images out of 200 images





This illustrations indicates how (raw data minus dark) divided by (flat field minus dark) equals flat field corrected data.
In the raw data, there is a gradient were the bottom of the picture seems to be darker compared to the upper part. With the corrected image, it can be seen that it is evened out.


This illustrations indicates how (one defocused flat field image minus dark) divided by (the average of 100 defocused flat field image minus dark) results in noise.
In the raw data, there is a gradient were the bottom of the picture seems to be darker compared to the upper part. With the corrected image, it can be seen that it is evened out.










Here are some examples of images taken at Big Bear Solar Observatory (BBSO) located in Big Bear Lake, California.



BBSO full disk H-alpha image


This image was recorded at 15:58:09 (UT) on June 23, 2003.


BBSO contrast enhanced full disk CaK-line image


This image was recorded at 16:14:15 (UT) on June 23, 2003.


Noise Power Spectra

The objective is to calculate the signal power to noise power ratio in order to detect structures of noise.