Planetary Imaging Today. Bryan Cogdell, Celestron LLC

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1 Planetary Imaging Today Bryan Cogdell, Celestron LLC

2 Overview Equipment Software Speckle Imaging Imaging Site and Conditions USB, FireWire, GigE Capture Exposure, Frame Rate, and Total Integration Time Pixel Size, Chip Size, and True Resolution Processing Archiving

3 Equipment - Telescope Aperture and focal length rule. Scope type? One with good aperture and focal length! Catadioptric scopes like SCTs are ideal for this. Telescope thermal currents are sometimes mistaken for local seeing: Allow the telescope to properly cool down. A C14 can take 1-2 hours, depending on storage temperature delta. C8 C11 C14

4 Equipment Telescope Collimation Collimate the telescope with the camera installed! This accounts for any mechanical differences between slip-fit connections like eyepieces and solid threaded connections that you are hopefully using with your camera. Collimate high in the sky, at least 70º above the horizon. Adjust telescope collimation so that defocused star looks perfectly concentric Anticipate the star moving out of the FOV.

5 Equipment - Camera High-speed camera speed and sensitivity are important Skyris USB 3.0 cameras, the first USB 3 astronomy cameras High speed webcam style cameras Digital cameras in video mode One-Shot Color Cameras: Very quick, convenient, and less expensive. A good choice for animation sequences, such as Jupiter rotation with Galilean satellites. Monochrome Cameras: Better sensitivity, more detail & color fidelity More expensive and requires a filter wheel + RGB filters

6 Equipment Mount and Accessories German Equatorial is highly preferred. Altitude-Azimuth mounts are acceptable but must deliver sub arc-minute drift over the course of 60 or more seconds. Though tracking is not as critical as deep sky imaging, high resolution planetary imaging is still requires accurate tracking in such a small FOV. Manually operated or motorized 1.25 filter wheel for monochrome cameras 1.25 RGB Filters A flip mirror is a convenient accessory. Motorized focuser Vibration suppression pads

7 Software Capture Software FireCapture Camera-included IC Capture, PlanCap, etc. Lucam Stacking Software Registax AutoStakkert Winjupos

8 Speckle Imaging (Lucky Imaging) Filters out the poor images from varying seeing. Leverages modern PCs, faster processors, and better software. Some programs not only select the sharpest images, but segments of that image as seeing fluctuates (AutoStakkert). You might call it software AO.

9 Imaging Site and Conditions It s all about SEEING CONDITIONS! Stay away from heat sources, rooftops, concrete, etc. A big percentage of local seeing is within just a few feet in altitude. Solar system objects are dynamic and ever-changing. Don t think of them as static objects. Plan for occultations, transits, conjunctions, anything that might be of interest. Use online ephemerids or WinJupos to plan your imaging session. Consider making animations of your event.

10 USB, FireWire, and Gigabit Ethernet USB is the most convenient option for consumers and does not require external power All PCs made today are equipped with USB 3.0. USB bus powers the device, no external power needed. FireWire is faster than USB 2.0, but slower than USB 3.0, and is a waning standard that Apple is moving away from. GigE Vision is primarily for machine vision applications, and not as practical for the consumer. It also requires external power.

11 Exposure Time Faster is better. Use the fastest possible exposure. Camera sensitivity and noise are the limiting factors. Atmospheric seeing can behave like motion blur. Just like daytime photography, faster shutters eliminate motion blur. Mia Long

12 Frame Rate Faster is better. Digital cameras of all types are getting faster. Images are stacked to increase the signal to noise Max integration time with planetary imaging is limited, so frame rate becomes critical. Deep sky imaging has an indefinite frame limit, since objects like galaxies are effectively static

13 Total Integration Time More is better HOWEVER, this time is limited due to planet s rotation! Total time varies depending on telescope resolution Jupiter: seconds Saturn: seconds Mars: seconds Time can be extended with image derotation, but individual movie files should stay in this range.

14 Pixel Size, Chip Size, and True Resolution With the exception of the Moon and Sun, Solar System objects are very small and only require a sensor big enough to cover a small field of view. Camera resolution is not the total number of pixels. Instead, resolution is the angular distance per pixel, also referred to as sampling.

15 Pixel Size, Chip Size, and True Resolution 5.6µm pixels 1/4 Format 4.4µm pixels 1/3 Format 3.75µm pixels 1/2 Format

16 APS-C Format

17 Capture Review Use fastest possible exposure time. Use highest possible frame rate. High gain is OK, even if noise is present. Limit the total integration time depending on the object you are imaging. Good collimation, scope cool down, and focus are critical! Time stamp all AVIs and stacked images. This is needed for derotation later.

18 Processing - Stacking AutoStakkert best implements speckle imaging. Resample 1.5x drizzle to increase image size. Export as 16 bit TIFF or PNG

19 Processing - Wavelets RegiStax does best with sharpening in wavelets. Set Initial Layer value to 2 Don t get carried away with the wavelets! It cannot overcome poor data.

20 Processing - Derotation WinJupos removes planetary rotation effects over time, allowing us to integrate more time capturing the planets! All data must be time stamped.

21 Why Skyris is the Best Planetary Imaging Camera Proven technology with Sony CCD sensors. Developed by industry-leaders: The Imaging Source and Celestron. The world s top planetary imagers including Christopher Go, Robert Reeves, and Thierry Legault beta-tested with great success and provided testimonials. Skyris speed and sensitivity capture more frames in less time, resulting in better images! Wes Higgins, Skyris 274M

22 New Astronomy Cameras from Celestron and The Imaging Source: Skyris USB 3.0 Skyris 618C and 618M Skyris 445C and 445M Skyris 274C and 274M Sony EXview HAD CCD ICX618AQA (Color) ICX618ALA (Monochrome) Sony EXview HAD CCD ICX445AQA (Color) ICX445ALA (Monochrome) Sony Super HAD CCD ICX274AQ (Color) ICX274AL (Monochrome) 640 x 480 (0.3 megapixels) 1280 x 960 (1.2 megapixels) 1600 x 1200 (1.9 megapixels) 5.60µm x 5.60µm pixel size Sensor Format Size Type 1/4 3.75µm x 3.75µm pixel size Sensor Format Size Type 1/3 4.40µm x 4.40µm pixel size Sensor Format Size Type 1/ frames per second 30 frames per second 20 frames per second

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24 Skyris 618M

25 Skyris 445C

26 Wes Higgins Skyris 274M

27 Skyris 618C Lance Lucero