Optical Systems. Camera

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2 The high-resolution planetary images in this second album were recorded in Prescott Valley, AZ (112º W, 34º 39 N) April 17, 2016 through August 6, A variety of optical systems were used, gradually increasing the effective focal length toward greater image size and scale. Optical Systems! Stellarvue SV x Scopetronix MaxPower (1280mm f/11.2)! Stellarvue SV x Televue PowerMate (1600mm f/14)! Celestron 6 SCT + 1.6x Scopetronix MaxPower (2400mm f/16)! Celestron 6 SCT + 2.0x Televue PowerMate (3000mm f/20)! Celestron EdgeHD x Scopetronix MaxPower (3759mm f/16) All optical systems were mounted on a Software Bisque Paramount MX GoTo equatorial mount controlled with TheSkyX Pro using Apple MacBook Pro computers. Camera! Canon EOS 60Da digital single lens reflex camera The camera has an APS-C 5184 x 3456 pixel imaging chip (17.9 Mpixel). Pixel size is 4.3 µm, yielding a Nyquist optimum of f/16. ISO range is 100 to 6,400. The camera was used in Crop 640x480 video mode that utilized the center 640 x 480 pixel area of the imaging chip at full resolution (much like a webcam). 8-bit MOV format videos were captured at 60 frames per second using Canon EOS Utility software (included with camera) on the same MacBook Pro computers controlling the mount. Videos were up to 5 minutes in duration, yielding up to approximately 18,000 image frames per video. The primary limitation of this camera was the inability to have exposure times longer than 1/60 sec due to the invariant 60 frames per second video capture rate. For bright objects like the Venus, exposure times shorter than 1/60 sec could be used; but for dimmer objects like Saturn, reasonable image brightest could only be obtained by increasing ISO, leading to higher

3 noise in individual frames. Video and Image Processing Astro IIDC As noted above, the Canon 60Da yields MOV format videos; this is an Apple OS video format. Initially these original MOV format videos were processed with Astro IIDC, an Apple OSX native program that can control a variety of video cameras, capture videos, stack video frames and do wavelet processing image enhancement. NOTE: The organization that produced Astro IIDC no longer exists; the program is not available anywhere. Approximately the best 10% of the video frames were selected and stacked. The resulting raw stacked images were saved in 16-bit color TIFF format. These raw images were optimized using wavelet processing to yield a final image that the author deemed pleasing. The final images were saved in 16- bit color TIFF format. Additional image enhancement, optimization and cropping were done with Adobe Photoshop. Although Astro IIDC is a very functional, comprehensive program, it became apparent that there were shortcomings. First, the color of planetary images appeared muted and unsaturated. Second, for video with low contrast features, such as brighter sections of the moon, Astro IIDC could not properly stack the video frames. Registax 6 Registax 6 is a well-regarded program for video frame stacking and wavelet opitimization. A comparison of final images from the same video processed with Astro IIDC and Registax revealed Registax delivered better and more consistent results. Registax is a Windows program; it was run on the MacBook Pro using Parallels Desktop and Windows 7. However, Registax cannot use MOV format videos; it requires AVI format video. A multistep process was required to convert MOV video to a usable AVI video. (see Current Processing Workflow below for complete processing steps)

4 With Registax the best frames (up to 30%) were selected and stacked. The resulting raw image was saved in 16-bit color TIFF format. This raw image was optimized using Registax wavelet processing to yield a final image that the author deemed pleasing. The final images were saved in 16-bit color TIFF format. Additional image enhancement, optimization and cropping were done with Adobe Photoshop. Autostakkert! Autostakkert! is a third video frame stacking program that is commonly used. However, it does not have the wavelet processing feature of Astro IIDC and Registax. A comparison of final images from the same video stacked with Autostakkert and Registax then wavelet optimized in Registax revealed Autostakkert yielded just slightly better images than Registax (in the author s opinion) and has become the default video stacking program. Autostakkert is also a Windows program and was run on the MacBook Pro using Parallels Desktop and Windows 7. Like Registax, Autostakkert cannot use MOV format videos; it requires AVI format video. As with Registax, a multistep process was required to convert MOV video to a usable AVI video. (see Current Processing Workflow below for complete processing steps) Atmospheric Dispersion One bane and complication for high-resolution planetary imaging (and lunar/solar) is atmospheric dispersion, particularly when the objects are lower in the horizon. As shown in the figure below, the atmosphere acts like a prism, separating and creating three RGB images that do not proper overlap. This reduces image resolution and sharpness.

5 For the images in this album, a simple process was used in Adobe Photoshop to overlap the three RGB images. With the color channels activated, the Red channel was nudged up and the Blue channel was nudged down to overlap the Green channel. The Venus images below shows the positive effect of this simple procedure. Current Processing Workflow 1) The MOV videos were converted to intermediate AVI format videos with Quicktime 7 Pro under Mac OSX. These intermediate AVI videos are not readable by Windows, so an additional step was needed. In Windows 7 the intermediate AVI videos were reprocessed and saved with the program VirtualDub, making an AVI format video readable by Windows, Registax and Autostakkert. 2) In Autostakkert the best video frames (up to 30%) were selected and stacked. The resulting raw images were saved in 16-bit color TIFF format. 3) The raw images were corrected for atmospheric dispersion in Adobe

6 Photoshop and, again, saved in 16-bit color TIFF format. 4) The corrected raw images were optimized using Registax wavelet processing to yield final images that the author deemed pleasing. These final images were saved in 16-bit color TIFF format. Any additional image enhancement, optimization and cropping were done with Adobe Photoshop. For This Album To make the images sufficiently large and easily viewable, all images in this album have been up-sampled 1 to 2 (640 x 480 to 1280 x 960) in Adobe Photoshop. An attempt was made to provide all the technical information about every image in the album. Unfortunately, some of that information was not recorded when the images were acquired and was not available. Fortunately, there is enough data to guide and optimize future video capture and processing for both readers and the author.

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10 JUPITER IMAGES Canon EOS 60Da in Crop 640x480 Video Mode Video Length = 4 minutes at 60 fps Optical Systems A: Stellarvue SV x Scopetronix MaxPower (1280mm f/11.2) B: Stellarvue SV x Televue PowerMate (1600mm f/14) C: Celestron C x Scopetronix MaxPower (2400mm f/16) D: Celestron C925 EdgeHD + 1.6x Scopetronix MaxPower (3759mm f/16) Image File Date Optics ISO Exposure Time Stacking Program Stacked 1 MVI1746 4/17/16 A Astro IIDC MVI1951 R 6/2/16 A Registax MVI R 6/7/16 A Registax MVI R 7/5/16 B Registax MVI2313 R 5/2/17 C 800 1/60 sec Registax MVI2790 6/15/17 C 800 1/60 sec Registax MVI2791 6/15/17 C 800 1/60 sec Registax MVI2792 6/15/17 C 800 1/60 sec Registax MVI2793 6/15/17 C 800 1/60 sec Registax MVI2794 6/15/17 C 800 1/60 sec Registax MVI2795 6/15/17 C 800 1/60 sec Registax MVI2796 6/15/17 C 800 1/60 sec Registax MVI2797 6/15/17 C 800 1/60 sec Registax MVI2798 6/15/17 C 800 1/60 sec Registax MVI2904 6/26/17 C 800 1/60 sec Registax MVI2905 6/26/17 C 800 1/60 sec Registax MVI2906 6/26/17 C 800 1/60 sec Registax MVI2907 6/26/17 C 800 1/60 sec Registax MVI2908 6/26/17 C 800 1/60 sec Registax MVI2909 6/26/17 C 800 1/60 sec Registax MVI3420 6/21/18 C 800 1/60 sec Registax MVI /24/18 C 800 1/60 sec Autostakkert MVI /6/18 D 800 1/80 sec Autostakkert 6000

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20 MARS IMAGES Canon EOS 60Da in Crop 640x480 Video Mode Video Length = 5 minutes at 60 fps Optical Systems A: Stellarvue SV x Scopetronix MaxPower (1280mm f/11.2) B: Stellarvue SV x Televue PowerMate (1600mm f/14) C: Celestron C x Scopetronix MaxPower (2400mm f/16) D: Celestron C x Televue PowerMate (3000mm f/20) E: Celestron C925 EdgeHD + 1.6x Scopetronix MaxPower (3759mm f/16) Image File Date Optics ISO Exposure Time Stacking Program Stacked 1 MVI /2/16 A Astro IIDC MVI /7/16 A Astro IIDC MVI /5/16 B Astro IIDC MVI3465 6/29/18 C 400 1/125 sec Autostakkert MVI /4/18 C 400 1/125 sec Autostakkert MVI /22/18 D 800 1/200 sec Autostakkert MVI /6/18 E 400 1/125 sec Autostakkert MVI /5/18 E 200 1/60 sec Autostakkert 6000

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25 SATURN IMAGES Canon EOS 60Da in Crop 640x480 Video Mode 1/60 sec at 60 fps for 5 minutes Optical Systems A: Stellarvue SV x Scopetronix MaxPower (1280mm f/11.2) B: Stellarvue SV x Televue PowerMate (1600mm f/14) C: Celestron C x Scopetronix MaxPower (2400mm f/16) D: Celestron C x Televue PowerMate (3000mm f/20) E: Celestron C925 EdgeHD + 1.6x Scopetronix MaxPower (3759mm f/16) Image File Date Optics ISO Stacking Program Stacked 1 MVI /2/16 A Astro IIDC MVI /2/16 A Astro IIDC MVI /7/16 A Astro IIDC MVI /7/16 A Astro IIDC MVI /7/16 A Astro IIDC MVI /7/16 A Astro IIDC MVI /5/16 B Registax MVI R 6/15/17 C Registax MVI R 8/8/17 C Registax MVI3431 Rs 6/21/18 C Registax MVI3434 Rs 6/21/18 C Registax MVI3455 As 6/29/18 C Autostakkert MVI3462 As 6/29/18 C Autostakkert MVI3474 Asd 7/22/18 D 3200 Autostakkert MVI3501 Asd 8/6/18 E 1600 Autostakkert 6000

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32 VENUS IMAGES Image 1: MVI3489 Image 2: MVI3490 August 6, 2018 Celestron C925 EdgeHD + 1.6x Scopetronix MaxPower (3759mm f/16) Canon EOS 60Da in Crop 640x480 Video Mode 1/125 sec at 60 fps for 5 minutes at ISO frames stacked with Autostakkert

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