10 kg rating and 12 kg payload
10 − 12 = −2 kg, or −20%. The declared payload exceeds the entered rating by 2 kg; adding a disclaimer does not make this a supported load.
Load this example in the calculatorMount payload comparison calculator
Compare a declared carried mass with the manufacturer rating for the exact mount configuration and identify an excess explicitly.
The interactive calculator loads in your browser. Without JavaScript, the method and worked examples below remain available.
What this calculation tells you
A mount rating is meaningful only with its stated configuration and payload definition. Enter a total you have independently added or weighed; this page does not inventory the telescope, camera, dovetail, guider and accessories for you.
Inputs and workflow
- Find the manufacturer rating for the operating mode and counterweight configuration you will use.
- Add the items carried by the mount according to that rating’s definition, keeping kilograms consistent.
- Compare the signed mass difference. A negative result exceeds the entered rating; a positive result is arithmetic headroom, not safety approval.
Formula and units
Headroom (kg) = entered rating − declared payload. Numeric headroom (%) = 100 × (rating − payload) / rating.
Worked examples
10 kg rating and 8 kg payload
10 − 8 = +2 kg, or +20%. This is only a comparison with the entered rating. It does not predict tracking precision or certify the assembly.
Load this example in the calculatorLimits before using the result
No universal 50% imaging rule is used. Balance, lever arm, wind, attachment security and tracking requirements matter beyond a mass total.
Manufacturer limits can change with operating configuration. Do not automatically include or exclude counterweights without checking the applicable definition. No brand-specific limit is prevalidated by a synthetic example.
Sources and method notes
- Sky-Watcher: WAVE150i configurations
Manufacturer ratings differ with counterweight configuration, illustrating why the entered limit must be configuration-specific.
Calculation notes maintained by AstroGearFit. Updated September 7, 2026. Examples are numerical demonstrations, not hands-on equipment tests. The method notes are currently in English; the existing interface language selector remains available.
Choose a calculation
Five focused checks with reproducible examples and explicit limits. These tools do not certify a complete equipment combination.
- Back-focus spacing calculator
Calculate whether your imaging train is too short, matched numerically, or too long for the specified sensor distance.
- Telescope field-of-view calculator
Estimate rectangular camera field width and height from sensor dimensions and effective focal length.
- Pixel-scale calculator
Convert camera pixel pitch and telescope effective focal length to angular image scale in arcseconds per pixel.
- Seeing and pixel-sampling calculator
Express an entered seeing FWHM in pixels using your camera pitch and effective focal length, without an automatic good/bad verdict.
- Mount payload comparison calculator
Compare a declared carried mass with the manufacturer rating for the exact mount configuration and identify an excess explicitly.
Filter sizing is paused. Whole-system compatibility needs verified interfaces, optical specifications and configuration-specific evidence.