ISO Advice from Jerry Lodriguss

From A Guide to Astrophotography with DSLR Cameras

Recommended ISOs with the latest generation of low-noise cameras

If above 60F (15.5C) then use ISO 1600

If between 40F to 60F (4.4C to 15.5C) then use ISO 800

If below 40F (4.4C) then use ISO 400

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