[sjastro]

In the 3C-273 thread there was no difference in the quality of the spectra for drizzle and normally combined sub exposures.
This was due to the telescope/camera set up not resulting in undersampled images and a limited degree of dithering between exposures.

Instead of using my BRC-250 scope, I used a 300mm lens which gave a resolution of 4.7 arcseconds/pixel resulting in undersampled images.
Each exposure of Gamma Velorum (10 X 20 seconds) was dithered using a spiral routine and displacement of 4 pixels.
These exposures were drizzled combined.

As a comparison another set of 10X20 second exposures without dithering were normally combined.

Since the drizzling process resamples the combined image by 2X, the normally combined image was also resampled 2X.

The results speak for themselves.

Steven