Webcam Imaging Webcam Imaging Choosing Your Webcam Other Equipment
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Overview Principles of webcam imaging Webcam Imaging Choosing your webcam Other equipment Part 1 Software Equipment Principles Choosing your webcam Poor man’s adaptive optics Good light sensitivity (<1 lux ) Freeze the seeing by capturing very short exposures Fast frame capture rate Capture large number of frames Good dynamic range Discard distorted frames Ideally CCD chip, not CMOS Stack frames to create an ‘average’ image Low/no image compression Image processing to sharpen image Bright objects – Planets, Moon, Sun, Fast connection Spacecraft Mono Chips Colour Chips Mono Chips Greater sensitivity > lower gain and/or Can be used on all subjects greater magnification Higher resolution than the equivalent Lower resolution than the colour chip equivalent mono chip All that is needed for most lunar imaging No colour filters and shorter Luminance layer with RGB from colour webcam processing webcam For full colour need to buy set of colour Low Hassle filters + wheel/slider (£200+) RGB AVI takes 3+ x longer to capture and 4+ x longer to process 1 Chip sizes Frame rate and compression – USB 1.1 640 x 480 (webcams), 1024 x 768, 1280 Low frame rate > low compression + low gain, but x 960 or 1616 x 1232 seeing not frozen + long capture times High frame rate > high compression + high gain, Small chips have faster frame rates and but seeing frozen + short capture times higher sensitivity (due to larger pixels) Larger chips cover larger area of sky, but slower frame rates + lower sensitivity Planets – Large chip size not important as optics/seeing limit resolution more often than chip size Moon/Sun – Larger chip = fewer captures to cover a large area Frame rate and compression – USB 2/ Firewire/GigE USB 2/USB3/Firewire/GigE = no compression Firewire - need for extra cables of laptops CamerasCameras GigE – Works over network cabling Larger chips > more data to send > lower frame rates 640 x 480 = max. 60 fps 1024 x 768 = max. 30 fps 1280 x 960 = max. 15 fps Microsoft Cinema HD LifeCam Meade Lunar and Planetary Imager (LPI ) Xbox Live Vision Bundle = cam + adaptor + software CMOS Chip - 640 x 480 colour 640 x 380 CMOS chip Max 30 fps (USB 2.0) £30 ( discontinued ) Requires destructive modifications Remove 4 x LEDs + glue on adaptor EBay - £2.99 2 Philips Toucam QHY5v or t Philips Toucam Pro II/SPC 900NC a.k.a. Orion Starshoot Planetary Imager Sony ICX098BQ colour chip Mono/colour CMOS Chip (v) - 752 x 480 Chip - 640 x 480 colour Mono CMOS Chip - 2048 x 1536 Max 10 fps (USB 1.1) Max 55 fps (752 x 480) Discontinued USB 2 £50 -£80 (+£60 for optional B&W £185 - £195 modification) Screw -in adaptor (£10 -£20) Celestron Neximage Atik Celestron Neximage (discontinued ) = Toucam Atik 1- HS2 webcam Cam + adaptor + software (outdated) Chip - 640 x 480 Celestron Neximage 5 Monochrome, air cooled, long exposure, 2592 x 1944 colour CMOS chip RAW mode 50 fps (640 x480 mode) Max 60 fps (320 x 240 mode) USB 1.1 £299 USB 1.1 Discontinued Imaging Source Lumenera DMK (mono) or DBK (colour) series Lumenera SkyNyx (colour or mono) Models based on ICX098BQ and ICX618ALA series imaging chips Chip - 659 x 494 to 1616 x 1216 Max 60 fps (659 x 494 models) Chip - 640 x 480 to 1280 x 960 Max 60 fps (640 x 480 models) USB 2 USB 2 or Firewire or GigE models 12 bit images £275 to £480 $1000 to $2700 Avoid DFK variant with (+ duty and VAT) built -in IR cut filter Chip now a bit out of date 3 Point Grey Flea 3 Basler Ace/Scout Sony ICX618ALA chip Sony ICX618ALA chip Sony ICX618ALA chip Chip - 640 x 480 Chip - 640 x 480 to 2080 x 1552 Max 120 fps Max 150 fps (640 x 480 models) GigE Vision USB 3.0, Firewire (800) standard or 12 bit images GigE Vision £520 16 bit images 16 bit images Problem with circular artefacts £540 to £1,600 and noise caused by overheating Atik Titan QHY IMG0H Sony ICX618ALA chip Sony ICX242 chip 640 x 480 – colour or mono versions Mono - 659 x 494 14 bit/8 bit output USB 2.0 Max. 50/30 fps Max 15 fps £379 16 bit images Includes Guide port and active cooling £465 – multi -purpose camera Includes Guide port and active cooling – multi -purpose camera Toucam – modifications TweakingTweaking youryour PhilipsPhilips Factory Settings Optimised non RAW WebcamWebcam RAW mode B/W Chip 4 Toucam firmware upgrades Toucam RAW mode Astrobond – WcRmac software RAW mode outputs data in black and white Optimised colour mode Software converts this into colour data RAW mode Most capture programs only display ‘live’ RAW image in b&w Programs such as Sharpcap and QCFocus will display live RAW image in low - resolution colour Need to debayer AVI before processing (option built in to Registax software) More difficult to judge focus and exposure in RAW mode Factory Settings RAW mode Optimised non RAW Toucam – Mono chip Toucam - LX modification Replace Sony ICX098BQ colour chip with Normal Toucam Pro limited to no more Sony ICX098BL than 1/5 th sec exposure £60 for B&W modification Add components and re -wire inside to allow for long exposures Good for up to 30 secs , longer with air cooling Uses separate Parallel port wire for LX control Parallel port to USB converter Connecting your webcam Barlows and Focal Reducers Remove lens Connect between webcam and Screw in adaptor telescope Fit any filters/barlow lenses 2 x Barlows essential for planets Put it in eyepiece socket on telescope Up to 4 x Barlows can be useful Focal Reducers useful for whole Sun or Moon 5 Filters (colour camera) Filters (mono camera) Beating the seeing – filters for IR cut filter – improves sharpness imaging of Moon and ‘Luminance’ and colour balance imaging of planets • Poor seeing > IR pass filter • Moderate seeing > red + IR cut • Good seeing > green + IR cut UV pass filter (or #47 violet) for imaging Venus Green + IR cut for imaging the Sun RGB filters = colour + IR cut Filters wheel or slider Computer USB lead between computer and webcam – >5 m = active lead Imaging session can take up over 4GB of Hard disk space Lots of hard disk space Plenty of memory and fast hard disc Image Capture Software Proprietary software with Camera Sharpcap (free) WXAstrocapture (free) Cratelets (free) K3CCDTools 3 (free demo) WcCtrl (free) FireCapture (for mono high speed video) Al’s reticle (free) 6.