Quote:
Originally Posted by troypiggo
I never once questioned the technique or theory. And my original question wasn't meant to imply that I did or didn't like the image. I was simply trying to understand why go to these lengths of getting extra resolution when there's more fundamental things (mainly noise and clipping as I agree that white balance is subjective and personal taste) that could be corrected in the image at normal resolution. Get that right first, then start worrying about resolution.
Again, just trying to understand the "why."
I shouldn't be surprised. I asked Bert here in another thread a while ago about why he was choosing to use his NII filter instead of Ha while he was still testing and trying to get flat fields. My reasoning for the question was innocent, just trying to understand.
His response was that many object like the Helix nebula emit strong NII, and that Ha filters wider than 3nm also pick up the NII spectrum. Correct statement, and I already knew that. But it didn't answer my question, and he wasn't imaging Helix, he was imaging Eta Carinae nebula or something that was strong Ha not NII.
I'm wondering if he was using Ha instead of NII he'd be getting stronger signal/noise and he wouldn't have to stretch so much.
Again. I'm no expert. That's why I'm asking the questions. To understand, not antagonise.
|
Troy I am truly sorry for seeming to be impatient or abrupt. I must read genuine questions more carefully before responding.
Most emission objects are about 50:50 NII:HA. NII emission needs close hot blue stars. I am hoping that by making images in HA and NII I can find some differences.
Leakage due to angular spectral shifts is a very valid question. This can only be resolved by taking many images with the object/s in question at both the centre of the field and the edge at both NII and HA.
Bert