Here is 160 minutes of Jupiter's rotation as the Great Red Spot emerges. Look closely to see the differential rotational speeds of the gas bands.
For this image, I captured (via FireCapture) 90 seconds of 480p video (5 ms exposure, gain 325, minimum 10k frames per capture) once every 5 minutes from 2:55 am (just before the Great Red Spot just entered view) to 5:30 am. All using an 8" EdgeHD and a Televue PowerMate 2.5x, at an effective focal length around 4350 mm (last time I estimated).
Focus was a little better than last time I attempted this (enough to see some details in the gas band and to faintly notice the GRS in live views), and so I worked to ease off on sharpening to get more nuanced detail. For each frame, I processed:
Autostakkert! 3- Image stabilization: planet with dynamic background
- Stack best 50%, AP size = 24
- Double stack reference, RGB align, sharpened (blend RAW for 50%)
- 3x drizzle
Registax- RGB auto balance (1024 processing box centered around Jupiter)
- (linear, no linked wavelets) Wavelet sharpen on the "conv" output from Autostakkert
- Layer 1: Denoise 1.0, Sharpen 0.45, at 100
- Layer 2: Denoise 1.0, Sharpen 0.45, at 100
- Layer 3: Denoise 0.0, Sharpen 0.45, at 100
- Layer 4: Denoise 0.0, Sharpen 0.45, at 100
- Layer 5: Denoise 0.0, Sharpen 0.45, at 100
- Layer 6: Denoise 0.0, Sharpen 0.45, at 100
Photoshop - Levels from 0 to 229, gamma 0.95
- Curves: linear contrast
- Vibrance and Saturation at 20
- Topaz denoise using the Low Light (default settings)
- Unsharp mask 150%, radius 2.5 pixels.
Estimated effective focal length: - Jupiter's diameter on Sep 3: 44.26"
- Jupiter's diameter on raw image: 320 px
- Camera pixel pitch: 2.9 micron
- Jupiter's diameter on raw image: 928 micron = 0.928 mm
- Equation: focal length = (206265 * image_length_mm ) / object_angular_size_arcsec
- So, (206265 * 0.928) / 44.26 ~ 4325 mm
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