Owl AstroGuides
In-depth articles on capturing and processing deep-sky images, with the reasoning and test data behind the advice.
Longer exposures versus multiple shorter exposures
Many short exposures or fewer long ones? Under light-polluted skies it barely matters; under dark skies longer subs win on SNR. The maths and a dark-site test.
Imaging the Pleiades properly
The Pleiades look easy, but bright stars and faint dust make M45 a dynamic range challenge. Tips for capturing and processing it with colourful, unclipped stars.
What is the best ISO for your DSLR for astrophotography?
ISO doesn't make your sensor more sensitive. How ISO affects read noise and dynamic range, and how to find the best ISO for your own DSLR.
A basic DSLR processing workflow in PixInsight
The four stages of processing DSLR data in PixInsight, from calibration and stacking to the stretch and the final touches, with the settings I start from.
Nikon vs Canon for astrophotography
Canon is the default DSLR for astrophotography, but sensor tests tell a different story. Colour depth, dynamic range and low-light scores compared.