Mercator projections, a comparison

Introduction While writing the previous post on Rijksdriehoeksmeting and OziExplorer, we came upon two map…

OziExplorer and Rijksdriehoeksmeting

Introduction OziExplorer is my favorite tool for working with topographical maps. Even in this era…

Serving your own PDOK maps

I am fascinated by navigation and maps. When I visit a new location one of…

White balance underwater

A well known phenomenon to divers is the fact that water absorbs light, the red…

OziExplorer maps from GeoTIFF

Introduction I still find Oziexplorer an excellent and versatile program for navigation, despite of the…

Window of opportunity

When taking wide angle photos underwater we observe a remarkable effect: if we look up…

Natural light photography underwater

Flash, Forrest, flash! Many starting photographers conclude there is not much light underwater and start…

Open Sesamy: Port-knocking using just one port

Port knocking is a mechanism to provide additional security to firewalling. Port knocking is normally used in firewalls.…

Photography articles in Dutch – 2008

These articles I wrote for the scuba diving club: Deel 1: Camera keuze Deel 2:…