Image Processing: Image Processing: Critical to Hubble Critical to Hubble

DiscoveriesDiscoveries

Presented byPresented by

Chris Lavin and Lucas DivineChris Lavin and Lucas Divine

The Hubble Space Telescope The Hubble Space Telescope (HST)(HST) HST program run by Space HST program run by Space

Telescope Science Institute Telescope Science Institute for NASAfor NASA

Quick Facts:Quick Facts: Deployed 1990Deployed 1990 Orbits Earth in 87 minutesOrbits Earth in 87 minutes 24.5 Thousand Pounds24.5 Thousand Pounds 10 times better than 10 times better than

Telescopes on EarthTelescopes on Earth

Employs 6 primary Employs 6 primary instruments for instruments for astronomical image astronomical image acquisition acquisition

Hubble InstrumentsHubble Instruments ObservatoryObservatory - Handles calibration and cross-instrument - Handles calibration and cross-instrument

issuesissues

Advanced Camera for SurveysAdvanced Camera for Surveys – Long distance – Long distance observationobservation

Fine Guidance SensorsFine Guidance Sensors – High speed measurements and – High speed measurements and pointing of the telescopepointing of the telescope

Near Infrared Camera and Multi Object SpectrometerNear Infrared Camera and Multi Object Spectrometer – – Specializes in near-infrared wavelengthsSpecializes in near-infrared wavelengths

Space Telescope Imaging SpectrographSpace Telescope Imaging Spectrograph – Breaks images – Breaks images up into component colors like a prismup into component colors like a prism

Wide Field Planetary Camera 2 Wide Field Planetary Camera 2 – The ‘Workhorse’ – The ‘Workhorse’ CameraCamera

Raw Data from HubbleRaw Data from Hubble

Hardware and software calibration in Hardware and software calibration in the On The Fly Reprocessing System the On The Fly Reprocessing System (OTFR)(OTFR)

Raw Data held in the Hubble Archive Raw Data held in the Hubble Archive for researchers and scientistsfor researchers and scientists

Stored in a compressed format and Stored in a compressed format and reprocessed when accessedreprocessed when accessed

Image Processing Image Processing TechniquesTechniques

SmoothingSmoothing: Noise reduction through : Noise reduction through filtering in astronomical images is very filtering in astronomical images is very important for specific information retrieval important for specific information retrieval

Image RestorationImage Restoration: : Almost all Hubble images have had some Almost all Hubble images have had some

unpredictable effects influence themunpredictable effects influence them Image restoration uses frequency domain Image restoration uses frequency domain

filters to remove the effects of these influencesfilters to remove the effects of these influences

Image Processing Image Processing Techniques 2Techniques 2

BrightnessBrightness: Showing the correct brightness : Showing the correct brightness (luminance) in an image is highly (luminance) in an image is highly important because distances are important because distances are calculated many times based on itcalculated many times based on it

ContrastContrast: Balancing of light and darks for : Balancing of light and darks for strengthening of details, also helps make strengthening of details, also helps make the image better looking to the human eyethe image better looking to the human eye

Image Processing Image Processing Techniques 3Techniques 3

Edge DetectionEdge Detection: To extract areas of : To extract areas of fine detail, Edge Detection is often fine detail, Edge Detection is often used. Many different filters and used. Many different filters and programs are used.programs are used.

SubtractionSubtraction: To detect movement in : To detect movement in time lapsed images, Subtraction is time lapsed images, Subtraction is used to see just the changes.used to see just the changes.

Building a Complete ImageBuilding a Complete Image

HST actually takes four HST actually takes four imagesimages

One magnified.One magnified. To combineTo combine

Scale MagnifiedScale Magnified Find overlap in each Find overlap in each

imageimage mergemerge

Adding ColorAdding Color

The often beautiful images that we The often beautiful images that we see on the news from the Hubble see on the news from the Hubble don't start out with all of those don't start out with all of those amazing colors. The Hubble actually amazing colors. The Hubble actually only takes gray scale images, so only takes gray scale images, so typically the images that the public is typically the images that the public is presented with are created from presented with are created from several pictures.several pictures.

Single Image ColoringSingle Image Coloring Color can be added to an intensity image Color can be added to an intensity image

by simply picking a color for each gray by simply picking a color for each gray scale value.scale value.

The following was created using Matlab.The following was created using Matlab.

Natural ColorNatural Color The HST can take three intensity images The HST can take three intensity images

using a Red Filter, a Green Filter, and a using a Red Filter, a Green Filter, and a Blue FilterBlue Filter

The three images are then used in an The three images are then used in an RGB ImageRGB Image

Representative ColorRepresentative Color The HST can take three intensity images The HST can take three intensity images

using a in the infrared spectrumusing a in the infrared spectrum The three images are then used in an The three images are then used in an

RGB ImageRGB Image

Infrared Image of Saturn

Natural Color Image of Saturn

Enhanced ColorEnhanced Color

Particular areas of Particular areas of color are takencolor are taken

Each Color Each Color represents an represents an atomatom R = Singly-ionized R = Singly-ionized

sulfur atoms sulfur atoms G = Hydrogen G = Hydrogen B = Doubly- ionized B = Doubly- ionized

oxygen atoms oxygen atoms

ConclusionConclusion

Image processing techniques that are Image processing techniques that are developed for the Hubble generally get developed for the Hubble generally get applied in other disciplines as wellapplied in other disciplines as well

Image processing is critical to Hubble Image processing is critical to Hubble discoveries because it allows for the key discoveries because it allows for the key information extraction within the image information extraction within the image