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Contents

Home page

revised 2024 Mar 1

Photography


Photography - creative & technical

revised 2019 Feb 7

A question of distance

revised 2010 May 16

Camera techniques

revised 2016 Feb 14

Digital image structure

revised 2007 Oct 18

A few of my pictures

new 2023 Oct 7

Standard image file formats

revised 2011 Nov 16

Pinhole photography

revised 2017 Jan 5

Orienteering, JavaScript and Video games


Orienteering, JavaScript and Video games

revised 2023 Dec 2

The Forest - orienteering simulation

revised 2024 Feb 24

The Forest - history

revised 2024 Jan 1

How to make limitless terrain for games in real time

revised 2024 Jan 25

The Forest - three.js/WebGL versions

revised 2024 Jan 1

The Forest - program design

revised 2021 Dec 24

Real orienteering: my O-maps

revised 2023 Dec 13

Astrophotography


Star photography - trails or no trails

revised 2016 Feb 2

Astrophotography with a simple compact camera

revised 2011 Mar 25

Camera following the stars - stacking

revised 2014 Jul 4

Photography through the telescope

revised 2011 Mar 26

Exposure settings for astrophotography

revised 2012 Aug 1

Dark, flat & bias frames - why I don't use them

revised 2015 Oct 26

Photographing the moon

revised 2015 Oct 26

Finding the target

revised 2012 Dec 9

Astrophotographic observations


My latest & best astrophotographs

revised 2019 Mar 30

Astroscapes

revised 2015 Apr 13

The Milky Way

revised 2015 Oct 28

Constellations

revised 2015 Nov 5

Deep sky: star clusters, nebulae & galaxies

revised 2015 Nov 5

Hydrogen alpha & OIII - by DSLR from suburbia

new 2019 Mar 30

Novae & supernovae

revised 2014 Jan 3

Solar System: Sun, Moon, planets, comets, etc

revised 2017 Apr 17

Geocentric or heliocentric?

new 2016 Dec 28

Some mysteries

new 2009 Dec 11

My telescope & camera


Telescope & observatory

revised 2012 Apr 17

Hints & tips for using a SkyWatcher telescope

revised 2011 Mar 22

Go to or not go to

new 2014 Jul 4

Resolution, field of view, etc

revised 2011 Mar 31

My usual astrophotographic process

revised 2015 Oct 26

Using GRIP


Introduction to GRIP

revised 2012 Mar 15

Download & install GRIP

revised 2018 Mar 3

What's new in GRIP

revised 2018 Mar 3

GRIP's main menu

revised 2009 Dec 2

Plotting realistic star charts

revised 2009 Dec 9

The batch menu

revised 2012 Mar 12

Processing steps for astrophotographs

revised 2014 Dec 17

Table of open images

revised 2009 Aug 20

The combination menu

revised 2009 Aug 20

Menus available on each image window

revised 2009 Oct 13

The image menu

revised 2009 Aug 20

The blob menu

revised 2010 Jan 15

The measurement menu

revised 2009 Aug 20

The geometry menu

revised 2009 Aug 20

The levels menu

revised 2009 Nov 19

The convolutions menu

revised 2009 Jul 27

The image help menu


The measurement table menus


Troubleshooting GRIP

revised 2015 Nov 6

How to...


Subtracting one photo from another

revised 2020 Aug 16

How to open RAW images in GRIP

revised 2007 Apr 10

How to recombine colour channels with GRIP

new 2007 Apr 9

How to measure the diameter of a pinhole

revised 2017 Jan 5

How to estimate unknown magnitudes of stars

revised 2010 Feb 15

Background correction


Panoramas & overlapping photos


Plotting positions of solar system objects

new 2008 Jan 3

Programming with GRIP


Download source code and API

revised 2015 Nov 3

What is Java?

revised 2011 Dec 14

Images in Java

revised 2012 Apr 17

ImFrame class structure

revised 2012 Apr 17

Pixel interpolation

revised 2012 Apr 17

Reading & writing images in Java

revised 2012 Apr 17

TIFF: little- or big-endian?

revised 2011 Nov 23

Image metadata

revised 2012 Apr 17

Blob detection and measurement

new 2011 Nov 23

Minimal GRIP application

revised 2012 Apr 20

Dark-adapted software

revised 2015 May 5

Programming angles

revised 2015 Apr 5

Odds & ends


Dark Skies

new 2017 Sep 23

In the Flower Garden

revised 2017 Sep 23

Elba, July 1988

new 2019 Jul 9

Why learn to program?

new 2015 Feb 3

The Mandelbrot curve

revised 2015 Sep 15

How these pages were made

revised 2010 Feb 27

Some links

revised 2023 Dec 13

How time travel paradoxes are really avoided

new 2017 Aug 23

Joyce Loebl Magiscan image analyser

revised 2019 Nov 7