Uploaded 12-Jan-10
Taken 12-Jan-09
Visitors 479

9 of 15 photos
Photo Info

Dimensions366 x 336
Original file size60 KB
Image typeJPEG
Color spacesRGB
Date taken12-Jan-09 14:18
Date modified12-Jan-09 14:18
Shooting Conditions

Camera modelNIKON D40X
Focal length18 mm
Focal length (35mm)27 mm
Max lens aperturef/3.5
Exposure1/60 at f/3.5
FlashFired, auto mode, return light detected
Exposure bias0 EV
Exposure modeAuto
Exposure prog.Unknown
ISO speedISO 200
Metering modePattern
Digital zoom1x
Light Box

Light Box

This is a light box used for taking "flats". It provides an even, white illumination through the use of ultra-bright LES lights inside and sign-makers plastic to diffuse the light. It is made of simple foam board. With the telescope pointed at the light box, I take a series of exposures (5 seconds or so). These exposures are then used during image calibration to flatten out uneven field illumination (vignetting) and to cancel out dust motes that may be in the optical train.