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Old 17-03-2017, 10:08 AM
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sjastro
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Drizzle vs Normal Integration at shorter exposures

Given the blooming issues the test was repeated using 30 X 2 sec sub-exposures.
This gave a pixel count of around 37,000 on the C emission line, well within the saturation limit.

The drizzle combined spectra being closer to the X-axis indicates dithering has reduced the background noise as expected.
On the negative side drizzling does introduce a small amount of noise which might explain the smaller peak heights in the drizzle combined image.

This is supported by SNR calculations.
The main C emission peak in the drizzle combined spectra has a maximum SNR of 195, in the normally combined spectra the maximum SNR is 228.

The conclusion is that there are no earth shattering improvements in using drizzle combined undersampled images.

Steven
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