pfile
m42 (great orion nebula) and ngc1977 (running man nebula) - 7h20m
7h20m on m42.
astromod canon 50d @ ISO800.
astronomik CLS clip-in filter
canon 200L f/2.8 + 2xTC @ f/8
main stack: 55x8 minutes exposure (7h20m)
shorter exposures for trapesium recovery: 10x15s, 10x30s, 10x60s
mount: orion skyview pro modded for GPUSB
autoguiding with PhD + meade DSI/celestron 50mm finderscope
calibrated, debayered (superpixel), registered and stacked with PixInsight 1.6.9
processing in PixInsight 1.6.9
final color tweaks in Lightroom 3
PI processing:
- reregistered integrated stacks
- HDRComposition
- dynamic background extraction
- created starmask from stretched and clipped Luminance + morphological dilation + atrous blur
- slight morphological selection (erosion) on stars (thru starmask)
- masked stretch (120 iterations to background = 0.120)
- histogram transformation
- HDRWavelet transformation
- histogram transformation
- extracted large scale features with atrous wavelets
- created small scale features with pixelmath (= original - large scale, rescaling on)
- histogram/curves on large scale features
- histogram and sharpening (atrous wavelets) on small scale features (thru star mask)
- new image = original + large scale + small scale with pixelmath (rescaling on)
- histogram tweak
- ACDNR
- created mask from luminance to protect background and stars
- atrous wavelet sharpening/noise reduction; bias ~0.3-0.4 on scales 1-4 (through mask)
- one more star reduction, first on smaller stars (original star mask) and then on larger stars (new star mask for only large stars)
- curves, ColorSaturation curves
- Bison Brewery IPA
Lightroom 3 processing:
- Split toning (highlights) to purple
- blue, red and orange saturation shift
- just a tiny bit of luminance noise reduction
- crop
notes: i found that with this combination of lens and teleconverter that there is significant coma and chromatic aberration. i'm not sure if it counts as CA but the R,G,B channels in each image are not aligned with each other in the original CR2s. in other words even in the center of the frame the centroids of the stars in each channel were a few pixels off from one another. i had to extract each channel of all of the 4 exposure lengths and re-register them against the green channel of the main stack in order to get everything aligned nicely.
m42 (great orion nebula) and ngc1977 (running man nebula) - 7h20m
7h20m on m42.
astromod canon 50d @ ISO800.
astronomik CLS clip-in filter
canon 200L f/2.8 + 2xTC @ f/8
main stack: 55x8 minutes exposure (7h20m)
shorter exposures for trapesium recovery: 10x15s, 10x30s, 10x60s
mount: orion skyview pro modded for GPUSB
autoguiding with PhD + meade DSI/celestron 50mm finderscope
calibrated, debayered (superpixel), registered and stacked with PixInsight 1.6.9
processing in PixInsight 1.6.9
final color tweaks in Lightroom 3
PI processing:
- reregistered integrated stacks
- HDRComposition
- dynamic background extraction
- created starmask from stretched and clipped Luminance + morphological dilation + atrous blur
- slight morphological selection (erosion) on stars (thru starmask)
- masked stretch (120 iterations to background = 0.120)
- histogram transformation
- HDRWavelet transformation
- histogram transformation
- extracted large scale features with atrous wavelets
- created small scale features with pixelmath (= original - large scale, rescaling on)
- histogram/curves on large scale features
- histogram and sharpening (atrous wavelets) on small scale features (thru star mask)
- new image = original + large scale + small scale with pixelmath (rescaling on)
- histogram tweak
- ACDNR
- created mask from luminance to protect background and stars
- atrous wavelet sharpening/noise reduction; bias ~0.3-0.4 on scales 1-4 (through mask)
- one more star reduction, first on smaller stars (original star mask) and then on larger stars (new star mask for only large stars)
- curves, ColorSaturation curves
- Bison Brewery IPA
Lightroom 3 processing:
- Split toning (highlights) to purple
- blue, red and orange saturation shift
- just a tiny bit of luminance noise reduction
- crop
notes: i found that with this combination of lens and teleconverter that there is significant coma and chromatic aberration. i'm not sure if it counts as CA but the R,G,B channels in each image are not aligned with each other in the original CR2s. in other words even in the center of the frame the centroids of the stars in each channel were a few pixels off from one another. i had to extract each channel of all of the 4 exposure lengths and re-register them against the green channel of the main stack in order to get everything aligned nicely.