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Re: [APML] Redo- Sagittarius - M8 to M17
Hi Alan!
This topic has become quite funny ;-)
>I was simply stating my observations. The first two links you provide
>are examples of what I was talking about. These are very 'grainy'. And
>the colors are not right.
Seeing that you are destroying my images, I'll have to fight for them <vbg>
Just joking.
About your first statement, the grainy look. They are everything but grainy :-) I have done several procedures, including SCNR, SGBNR, wavelets and deconvolution. I am sure that there is no noise at all, so there is no real grain in there. In fact, I fear that maybe I lost some high frecuency details.
As Vicent said, this grainy look comes from the miriad of stars in the field. They are very deep pics, at least for the equipment, and for the wield field nature of the image you'll have to consider the high density of stellar object. Also this look may be enhanced with my wavelet processing, with included some increased contrast in low-medium scale features.
Now, the colors... I admit that I went too far with saturation in those pics, but I assure you that the color balance is very accurate, at least with large scale objects. I used Provia 400F, not E200, so the blues are by far better recorded. That is also the reason why the Milky Way looks so bright and blue.
>Not all of them. As I stated, most of the images posted in the last
>several months do look funny. That statement means that most of the
>images posted here, which had major processing in PI LE, have a funny.
Well, I guess that you are thinking mainly in images from Vicent, Carlos S. and me. We have been experimenting with new techniques, specially in the star shaping field. We have not mastered them at all, so we have just partially succedeed in our results showed here. Sometimes the procedure makes the stars look opaque, others grainy, others blured... Is just a matter of fine tunning our abilities and gain more experience. We do believe that stars should not look as flat white discs, but gaussian like functions, with colored haloes. The main problem with my pics, in particular, is that I push them to far in the digital process that I am dealing with nebulosities just above the background "noise", with the consecuence that star haloes that hide themselves in a few dark levels, now are distributed in a wider and brighter range. I had several headaches trying to recover a "normal" aspect to the stars, without a "painted over the image" feeling.
>What I want to know is if anyone else sees this, and can possibly
>explain it. The 2 Orion shots are not soft, they are the opposite.
>Maybe over-sharpened? I can not be the only one who notices. I'm
>basically going on 'gut' reactions from someone whose seen thousands of
>images posted over the years.
Yes, I agree with you. You just have to see those stars before the star shaping procedures. I cannot do magic, yet... ;-)
Next time I process those image I'll add much more frames, and be more conservative in the processing. I consider my work untill now (and a few months more) just as educational experiences, going as far as I can (specially in image deepness). I have learn a lot about image processing, but have not mastered that at all. C'mon, this is a hobby after all, and we practice it becouse is funny. =) And I have a lot of fun processing my images!!!!
Regards,
Carlos Milovic F.
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