Let's refocus
My first goal is to guarantee I can get good images of the aurora.
I am getting distracted by how to get good images of star fields with the Nikon.
SO - Focus!
What I want is either/and 1) good still photos 2) good time lapse 3) good movies.
None of these require stacking. (except maybe good still photos) However, I would prefer my stills not be so long as to destroy the linear detail in the auraorae.
So - I need to concentrate and practice getting good still night photos. Then work on time lapse and movies.
points along this path:
1) determine good exposure values for various times. Check these for image quality. I will have to vary the ISO, and there will be a point at which they become too noisy.
2) learn to do the focusing in the dark without fail.
3)test the various exposure values, put out comparison images for criticism.
after this
Move on to time lapse. Learn how to change into a movie that doesn't go so fast
And then to movies.
Now that we are focused, let's record what I have learned today
De-bayering:
My chip has a bayer filter, raster filter, over the chip. It produces a RAW image with green, red, and blue pixels. There are twice as many green as red and blue pixels.
De-bayering takes this image, which when magnified has a checkerboard look, and changes it into pixels with RGB content.
Perhaps I can see this if I change it to TIFF!
When I open a .NEF in PS - I do not see the rectangular pattern. Hmm.
When I open a .NEF in Nebulosity, I DO see the rectangular pattern and it is in B/W
If I then "De-mosaic" the imaging in Neb, I lose the pattern, and it becomes color.
However, it is too green. (expected). There is a control for how the colors are done, a 3X3 matrix.
This three by three matrix has nothing to do with the Bayer grid, it describes input color (columns) and output colors (rows). Hard to know how to do this properly.
Later - try it in PixInsight
AHH! when I covert to TIFF in PS - and then re-open in Nebulosity, the Bayer pattern is gone.
My first goal is to guarantee I can get good images of the aurora.
I am getting distracted by how to get good images of star fields with the Nikon.
SO - Focus!
What I want is either/and 1) good still photos 2) good time lapse 3) good movies.
None of these require stacking. (except maybe good still photos) However, I would prefer my stills not be so long as to destroy the linear detail in the auraorae.
So - I need to concentrate and practice getting good still night photos. Then work on time lapse and movies.
points along this path:
1) determine good exposure values for various times. Check these for image quality. I will have to vary the ISO, and there will be a point at which they become too noisy.
2) learn to do the focusing in the dark without fail.
3)test the various exposure values, put out comparison images for criticism.
after this
Move on to time lapse. Learn how to change into a movie that doesn't go so fast
And then to movies.
Now that we are focused, let's record what I have learned today
De-bayering:
My chip has a bayer filter, raster filter, over the chip. It produces a RAW image with green, red, and blue pixels. There are twice as many green as red and blue pixels.
De-bayering takes this image, which when magnified has a checkerboard look, and changes it into pixels with RGB content.
Perhaps I can see this if I change it to TIFF!
When I open a .NEF in PS - I do not see the rectangular pattern. Hmm.
When I open a .NEF in Nebulosity, I DO see the rectangular pattern and it is in B/W
If I then "De-mosaic" the imaging in Neb, I lose the pattern, and it becomes color.
However, it is too green. (expected). There is a control for how the colors are done, a 3X3 matrix.
This three by three matrix has nothing to do with the Bayer grid, it describes input color (columns) and output colors (rows). Hard to know how to do this properly.
Later - try it in PixInsight
AHH! when I covert to TIFF in PS - and then re-open in Nebulosity, the Bayer pattern is gone.
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