1. Cooled astro-CMOS vs DSLR
A cooled CMOS astro camera gives regulated cooling (repeatable darks, far less thermal noise) and
no IR-cut filter blocking hydrogen-alpha — the standard for deep sky. A DSLR/mirrorless you may
already own is a fine, cheaper start, especially modded, but expect more thermal noise from the
uncooled sensor, especially on warm nights.
2. Mono vs one-shot color (OSC)
- OSC is simpler — one camera, color in every frame, less time per target.
- Mono + filters collects more light per pixel and shines for narrowband, at the cost of more
gear and acquisition time.
This is its own decision with real trade-offs — see
mono vs one-shot color before committing.
3. Pixel size vs your scope (sampling)
Match pixel size to your focal length so you're not badly over- or under-sampled. As a rough guide,
aim for an image scale around 1–2 arcsec/pixel for typical seeing; compute it from your camera's
pixel size and scope focal length rather than guessing.
4. Practical specs to compare
- Sensor size (fits your scope's image circle?).
- Read noise & full-well (low read noise favors many shorter subs).
- Cooling delta and power needs.
- Bit depth (12–16-bit ADC).
5. Budget tiers (confirm current models)
- Entry: a used/modded DSLR you already have, or a small cooled OSC.
- Mid: a cooled OSC sized to your scope; or step to mono + filters if narrowband is the goal.
---
How sensors capture light: how camera sensors work. Match the camera to optics in