Drizzling oversampled planetary images

[JamesF]

The issue of drizzle and oversampled images has come up once or twice recently, perhaps mostly in threads discussing Craig Stark's paper explaining how drizzle works.

I've said a few times that I didn't think drizzle worked for oversampled images, or at best became less effective as the sampling rate became better than unity. There's been a nagging issue regarding planetary imaging though. I guess most people imaging the planets are oversampling and potentially oversampling quite heavily. Yet drizzle does appear to drag more detail out of the image. Despite my viewpoint, I certainly wouldn't dream of denying that some of the people posting drizzled images on SGL are producing absolutely outstanding images.

Anyhow, I've just come across this posting by Emil Kraaikamp (author of AS!2). Whilst it appears (by my reading) to back my position it still leaves me pondering on the (fairly obvious) question "Why do people perceive an increase in detail after applying drizzle?". Is it really just a glorified rescale that makes existing detail more discernable to the human eye?

James

[lensman57]

The issue of drizzle and oversampled images has come up once or twice recently, perhaps mostly in threads discussing Craig Stark's paper explaining how drizzle works.

I've said a few times that I didn't think drizzle worked for oversampled images, or at best became less effective as the sampling rate became better than unity. There's been a nagging issue regarding planetary imaging though. I guess most people imaging the planets are oversampling and potentially oversampling quite heavily. Yet drizzle does appear to drag more detail out of the image. Despite my viewpoint, I certainly wouldn't dream of denying that some of the people posting drizzled images on SGL are producing absolutely outstanding images.

Anyhow, I've just come across this posting by Emil Kraaikamp (author of AS!2). Whilst it appears (by my reading) to back my position it still leaves me pondering on the (fairly obvious) question "Why do people perceive an increase in detail after applying drizzle?". Is it really just a glorified rescale that makes existing detail more discernable to the human eye?

James

Hi James,

I asked the same question a while back in one of my posts, trying to learn the ropes as a total novice. I really am interested in this topic and perhaps a word from one of the software engineers could be helpful. I still drizzle in AS!2 but I only see a percieved "increase" in detail if there is very fine detail like a narrow band on a planet present and the capture has just the right amount of S/N ratio. Then again this could just be my imagination .

Regards,

A.G