mr_rodge, you can open the window on the C150 but I didn't fancy it yesterday, too cold!
Do you have a DSLR? If so I'd follow these:
- Adjust ISO according to lighting conditions. If it's semi-sunny (as in these shots) then ISO 200 should do. ISO 400 starts to make the images quite grainy, so I avoid this unless it's particularly dark.
- Set manual mode, aperture around f8 gives you a good depth-of-field and shutter speed of around 1/200 should be manageable if you don't zoom in too far. Remember though that 1/200 is still relatively slow, so you need a steady hand otherwise you'll blur it. If you're blurring them still, raise the shutter speed to around 1/320. Don't go too high, as you'll get darker images.
- Don't rest the lense on the window, as it'll vibrate and give you a blurred image. Steady your hand on the window and hold the lense very close but not touching.
- If possible, have someone turn the aircraft so you're looking down at the ground, rather than having to point the lense down which tends to give reflections.
- The window will take out a lot of the sharpness and natural contrast from the image. Simply use photoshop (or another free editing software) to add some sharpening and contrast so that you get proper shadows.
That's about all I can offer in a quick summary!