M45 Pleiades in Taurus - with Canon 20Da and 135mm Canon L-series telephoto at f/2.8 for stack of 4 x 6 minute exposures at ISO 400 (2 images c-added, 2 images averaged) - taken from home under ideal conditions Sept 30 2008. Field of view across short dimension of frame equals that of typical binoculars. Faint nebula above M45 is IC 353.
M45 with 200mm lens at f/4 for stack of two 4-minute exposures at ISO400. Canon 20Da camera. October 21, 2006
The Pleiades in Taurus, and the California Nebula, NGC 1499, in Perseus. The small blue reflection nebula at centre right is IC 348. This is a stack of 5 x 6 minute exposures with the 135mm Canon L-Series lens at f/2.8 and Canon 5D MkII at ISO 800. From home on a clear winter's night. Original exposures were technically overexposed but processed up well with huge increases in contrast introduced at every stage, from RAW to layered Photoshop, to final flattened TIFF. Several masks employed to equallize (flatten) the brightness gradients across the image from radial lens vignetting, linear edge camera lens box shadowing, and linear sky gradients. But having originals that were overexposed provided lots of signal, despite having only 5 exposures median combined, allowing the very faint nebulas to be brought out without significant noise. Having a cold (-5°C) camera helped too.
