The Moon boasts an unexpected variety of landscapes - including volcanic features, sinuous valleys and ghost craters - which are readily visible from Earth. This practical guide explains and demonstrates how you can capture impressive images of our nearest neighbour in space using a variety of different techniques. As the first guide to be dedicated to modern lunar imaging, this volume offers an in-depth and illustrated approach to common optics, the essentials of digital images, imaging devices, and image processing software. Even in light-polluted areas, the countless features and finest details of the Moon can be captured by following the instructions in this comprehensive and accessible guide. Covering equipment ranging from smartphones and DSLRs to specialist planetary cameras, whether you are a novice without a telescope, an amateur developing your skills in imaging, or an experienced astrophotographer, you will benefit from the hints, insights and expertise within.

Preface page xiii

1 Introducing lunar imaging 1

1.1 Seven ways to shoot the Moon 1

      1.1.1 Beginners’ equipment 3

      1.1.2 Intermediate equipment 5

      1.1.3 Advanced equipment 8

1.2 The Moon’s changing appearance 11

      1.2.1 Monthly cycles and proper motion 11

      1.2.2 Apparent diameter variation 12

      1.2.3 Visibility of lunar features with respect to phase 12

      1.2.4 Seasonal cycle and altitude variation 13

      1.2.5 Near-side visibility and librations 14

      1.2.6 Colongitude 16

2 Choosing your imaging equipment 17

2.1 Shared, fundamental characteristics 17

2.2 Optical flaws 17

2.3 Resolving power 19

2.4 Photolenses and zooms 20

2.5 Refractors for beginners 23

2.6 Advanced refractors 24

2.7 Reflectors and catadioptric telescopes 26

2.8 Mounts, tripods, lunar tracking, and exposure limit 30

      2.8.1 Lunar imaging with a tripod; motion blurring 30

      2.8.2 Photo and video tripods 33

      2.8.3 The Dobsonian mount 34

      2.8.4 The German-type mount 36

      2.8.5 Alt–az and equatorial fork mounts 37

      2.8.6 Power supply 39

2.9 Image sensors 40

      2.9.1 What are CMOS and CCD sensors? 40

      2.9.2 Readout modes 46

      2.9.3 Sensor cooling for short exposures? 47

      2.9.4 Global vs. rolling shutters 48

      2.9.5 Converter resolution 49

      2.9.6 High-dynamic-range (HDR) sensors 50

      2.9.7 Color sensors vs. monochrome sensors 51

      2.9.8 Sensor format, number of pixels, and resolution 53

      2.9.9 Sensor efficiency 54

      2.9.10 The frame-rate dilemma with a planetary camera 58

      2.9.11 Electric disturbances, computer performance 59

2.10 Image and video formats 62

      2.10.1 JPEG compressed images 62

      2.10.2 TIFF uncompressed images 63

      2.10.3 FITS astronomical-format images 63

      2.10.4 Raw formats (NEF, CR2, MTS ...) 64

      2.10.5 Video formats for webcams 64

      2.10.6 DSLR video modes 65

      2.10.7 SER astronomical video format 66

      2.10.8 EXIF data 66

2.11 Camcorders 67

2.12 Webcams 69

2.13 Analog-output video cameras and electronic eyepieces 72

2.14 Digital still cameras 75

      2.14.1 Compact and bridge cameras 75

      2.14.2 Hybrid and DSLR cameras 77

      2.14.3 Dimension of the Moon with compact and DSLR cameras 79

      2.14.4 High dynamic range (HDR) by bracketing 80

      2.14.5 Choosing the sensitivity and exposure 81

      2.14.6 Setting the image type 82

      2.14.7 Focusing with the viewfinder or with LiveView 84

      2.14.8 Flipping the mirror in advance 85

2.15 Planetary and industrial cameras for the Moon 85

      2.15.1 Planetary cameras 85

      2.15.2 Industrial cameras 88

      2.15.3 Camera-to-computer interfaces 90

3 Adapting your imaging device to the instrument 91

3.1 Digiscopy 91

      3.1.1 Plan B: digiscopy (or afocal projection) 91

      3.1.2 Digiscopy with camcorder, bridge camera, or compact camera 91

      3.1.3 Digiscopy with a smartphone 94

3.2 Prime-focus imaging 94

      3.2.1 Some possible back-focus concerns and solutions 94

      3.2.2 Adapting a DSLR to prime focus 96

      3.2.3 Adapting a webcam to prime focus 96

      3.2.4 Adapting a video camera to prime focus 97

      3.2.5 Adapting a planetary camera to prime focus 98

3.3 Imaging with high magnification 99

      3.3.1 Variable- or constant-ratio magnification with Barlow lens 100

      3.3.2 Variable-ratio magnification with eyepiece projection 101

      3.3.3 Webcam with Barlow lens or eyepiece projection 104

      3.3.4 DSLR with Barlow lens or eyepiece projection 104

      3.3.5 Planetary camera with Barlow lens or eyepiece projection 104

      3.3.6 Assembling the imaging train, focusing, and shooting 105

3.4 Image-field flaws 108

      3.4.1 Field curvature, coma, and astigmatism 108

      3.4.2 Vignetting 111

      3.4.3 Tilt 112

      3.4.4 Dust 113

      3.4.5 Dithering, drizzling, and ... much too perfect lunar tracking! 115

      3.4.6 Distortion 117

4 Tuning your telescope for lunar imaging 119

4.1 Marrying filters, sensors, and telescopes 119

4.2 Fixing chromatism of an achromatic refractor 119

4.3 Red and near-infrared filters 121

4.4 How sensors match filters – or not! 121

4.5 Tuning the eyepiece holder 124

4.6 Tuning a reflector for lunar imaging 127

      4.6.1 Baffling 127

      4.6.2 Painting and flocking 128

      4.6.3 Mirror stress, astigmatism, and offset of a Newtonian telescope 131

      4.6.4 Spider vanes, secondary-mirror diameter 133

      4.6.5 Re-polishing or replacing the mirror 136

      4.6.6 Getting rid of the secondary mirror? 137

4.7 Preparing a telescope for lunar imaging 139

4.8 Polar alignment (for lunar imaging) 140

4.9 Balancing the telescope 141

4.10 Reducing vibrations of a Newtonian telescope 142

4.11 Managing turbulence and cooling 144

4.12 Video-assisted collimation 147

      4.12.1 Preparing the collimation 149

      4.12.2 Collimating a Newtonian telescope 149

      4.12.3 Collimating a Schmidt–Cassegrain telescope 152

4.13 Mechanical and optical bending 152

4.14 Avoiding and eliminating dew 154

5 Wide-field lunar imaging 156

5.1 The Moon in a landscape 156

5.2 Lunar halo 157

5.3 Earthshine 162

      5.3.1 Earthshine without a telescope 162

      5.3.2 Earthshine with a telescope 166

5.4 Moon, stars, and planets 167

      5.4.1 Moon, stars, and planets without a telescope 167

      5.4.2 Moon, stars, and planets with a telescope 170

5.5 Lunar eclipses 170

      5.5.1 Umbra and penumbra 170

      5.5.2 Brightness variation during a lunar eclipse 171

      5.5.3 Lunar eclipse with a webcam and short-focus optics 172

      5.5.4 Lunar eclipse with a still camera and short-focus photolens 173

      5.5.5 Lunar eclipse with a telescope and a DSLR 175

      5.5.6 Maximal exposure, field width, and focal length 176

      5.5.7 Lunar-eclipse movie 177

      5.5.8 Lunar-eclipse schedule: 2016–2030 184

      5.5.9 Occultations 186

      5.5.10 Video time insertion 188

6 High-resolution lunar imaging 190

6.1 Sampling: finding the right magnification 190

      6.1.1 General formula 192

      6.1.2 Accurate formula 192

      6.1.3 Adjusting the sampling and the F/D ratio 193

6.2 Colored and dichroic filters 194

6.3 The atmospheric-dispersion corrector (ADC) 195

7 Essential image processing 198

7.1 Monitor calibration 198

7.2 Processing flowcharts 199

7.3 Stacking 200

7.4 Some traps to avoid in lunar image processing 205

7.5 Sharpness 206

      7.5.1 Acutance and unsharp mask 206

      7.5.2 Multiple-resolution unsharp mask 208

      7.5.3 Wavelets 208

      7.5.4 Convolution and deconvolution 210

7.6 Contrast and inflexion points 211

7.7 Noise reduction ... and how to avoid noise 214

      7.7.1 Avoiding noise during acquisition 214

      7.7.2 Negative wavelets 217

      7.7.3 Other noise-killer and image-restoration algorithms 217

      7.7.4 Threshold unsharp mask 218

8 Advanced image processing 219

8.1 Balancing the terminator gradient 219

8.2 Local contrast with diffuse selection 219

8.3 Multiple-layer processing 222

8.4 Unveiling ray systems 223

8.5 Enhancing the contrast of pyroclastics 225

8.6 Emphasizing wrinkle ridges, domes, and ghost craters 225

8.7 Detecting and fixing rebounds 227

8.8 The colored Moon 229

8.9 Inverting the image 233

8.10 Making a giant image: the mosaic 234

8.11 HDR images with software or manual combination 235

8.12 Tone mapping 238

9 Making 3D lunar images 241

9.1 Three-dimensional anaglyph 241

9.2 Spherical projection with Photoshop® 244

9.3 Albedo-based 3D 245

9.4 Casting a photograph onto LOLA’s DEM 246

9.5 Creating a modern Wright globe 248

      9.5.1 With a videoprojector 248

      9.5.2 With WinJupOs 249

      9.5.3 With Celestia 250

      9.5.4 Spherical rectification 252

10 Measuring and identifying lunar features 253

10.1 Horizontal resolution 253

10.2 Vertical resolution 253

10.3 Identification 255

11 Photogenic features of the Moon 257

11.1 Categories of lunar features 257

11.2 Maria 257

11.3 Mountains 260

11.4 Cast shadows 264

11.5 Highlands 266

11.6 Sunrise and sunset in craters 268

11.7 Phase effects 269

11.8 Grabens, linear rilles, rifts 271

11.9 Valleys 273

11.10 Secondary craters, chain craters 274

11.11 Pyroclastics 277

11.12 Magcon 279

11.13 Domes, ghost craters, and ridges 280

11.14 Libration 282

11.15 Monitoring transient lunar phenomena (TLP) 283

12 Naming, archiving, printing, and sharing lunar images 287

12.1 Selenographic, cartesian, and xi–eta coordinates 287

12.2 Image-file naming 290

12.3 Archive management 292

      12.3.1 CD, DVD, Blu-ray 292

      12.3.2 USB keys, USB disks 293

      12.3.3 Cloud storage 294

12.4 Offset printing and pre-processing 294

12.5 Preparing images for the Web 296

12.6 Matching printing formats and sensor formats 297

12.7 Papers and inks 299

Appendix 1. Maps of the Moon, the Lunar 100, and other targets 301

Map of the Moon 301

Lunar 100 301

Lunar-mission landing sites 307

Appendix 2. Webpages, books, and freeware for the Moon 309

Professional lunar images 309

Some amateur lunar images 310

Some personal pages about industrial/planetary cameras 310

Organizations for lunar imaging and observation 310

Select bibliography 311

Processing and image-acquisition freeware for lunar images 312

Other technical and specific graphical freeware 314

Appendix 3. Figure data 315

Index 321

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