The Rig Builder is an interactive tool for testing real-world astronomy and astrophotography setups. Pick your telescope, imaging camera, mount, power supply, and (optionally) guiding gear from Equipment Cards, and the Rig Builder will calculate payload headroom, pixel scale and estimate power draw, battery run-time, and more. A live deep sky field-of-view (FOV) simulator powered by Aladin Lite, or solar system object images from NASA, show how your framing will look on the sky for deep-sky and solar-system targets.

Quick Start

1) Choose a Rig Mode: Imaging, Visual, or Smart Telescope.
2) Select gear for each slot: Telescope / Optics, Imaging Camera, Mount, Power Supply, and optionally a Guide System.
3) Set your Seeing (Poor / Average / Good) and Use Case (for example, deep-sky targets or the Moon).
4) If you use one, enter a Reducer / Barlow multiplier (e.g. 0.85 or 2.0).
5) If your camera supports it, choose a Binning mode (e.g. 1×1, 2×2).
6) For cooled cameras, toggle the Cooler and set the percentage power via the slider.
7) The summary updates instantly, and the Sky viewer shows your FOV. Use the rotation and zoom controls to fine-tune framing on your chosen target.

Modes

• Imaging — For astrophotography. Shows a red FOV box for the main camera. You can also show a yellow FOV box for the guide system. Supports reducer/barlow multipliers, binning, and cooler % (if used). Power usage and run-time are based on your full imaging rig.
• Visual — For eyepiece observing. Shows a true-field circle (TFOV) for your eyepiece instead of camera boxes. TFOV is calculated from the eyepiece’s field stop when available, or from apparent field of view and magnification as a fallback.
• Smart Telescope — For all-in-one scopes with built-in profiles (for example, “Wide” and “Tele”). Shows a single red FOV box based on the selected profile. The guide FOV is disabled in this mode. Where provided, a manufacturer run-time note is displayed in the summary alongside the usual rig information.

Plain-English Quick Guide

• Field of View (FOV) — Think of this as the size of the “window” your camera sees. Shorter focal length or a larger sensor gives a wider view; longer focal length or a smaller sensor gives a narrower, more zoomed-in view.
• True Field of View (TFOV, Visual) — The size of the patch of sky you see through an eyepiece. Bigger field stops or lower magnification give a wider circle; high magnification gives a small circle.
• Pixel Scale — How much sky each camera pixel covers (arcseconds per pixel). Smaller numbers mean finer detail, but they demand steadier skies and better tracking. The Rig Builder compares your pixel scale to your chosen seeing/use case and labels it under-sampled, well-matched, or over-sampled.
• Binning — Groups camera pixels together. This makes each “super-pixel” larger, which increases the pixel scale (less detail per pixel) but boosts sensitivity and reduces file size. Good for faint targets or rough framing.
• Guide Scale — The pixel scale of your guiding camera. Very small guide scale can “chase the seeing”; very large guide scale can miss tiny drifts. The tool flags combinations that are extreme either way.
• Guide Ratio — Imaging focal length divided by guide focal length (with OAG, the guide side uses the main scope). A moderate ratio is usually easiest to guide well; very high ratios can reveal flexure or tracking issues more harshly.
• Payload vs Capacity — Your total gear weight versus the mount’s rated capacity. Staying comfortably under the limit helps stability, guiding performance, and wind resistance.
• Power & Run-time — Total power draw (watts) from the mount, cameras, cooler, and accessories versus your battery capacity (watt-hours). More watts = shorter run-time. Mains power is effectively unlimited.

Slots & Controls

• Telescope / Optics — Sets focal length and aperture, which drive pixel scale, FOV, and (in Visual mode) magnification. In Imaging mode you can apply a reducer/barlow multiplier to change the effective focal length.
• Imaging Camera — Sensor size and pixel size determine pixel scale and FOV. If binning is supported, selecting a bin mode adjusts the effective pixel size and recalculates the scale.
• Mount — Adds payload capacity and typical power usage (tracking vs slewing). The summary compares your rig’s total weight to this capacity and flags if you’re nearing or over the limit.
• Power Supply — Battery or mains. For batteries, the capacity (watt-hours) is used to estimate run-time based on your current power draw. For mains power, run-time is effectively unlimited.
• Guide System (Imaging mode) — Either a separate guide scope + guide camera, or OAG (off-axis guiding). When enabled, a yellow guide FOV can be shown. Guide scale and guide ratio are calculated from this slot.
• Seeing & Use Case — Tell the tool roughly how steady the sky is and what kind of target you’re planning for (for example, deep-sky nebulae or the Moon). This is used to judge whether your pixel scale and focal length are a good match.
• Binning — When available, changes effective pixel size (e.g. 2×2 doubles pixel size) and updates pixel scale accordingly. Higher binning trades resolution for sensitivity.
• Rotation — Rotates the FOV overlays to match how you intend to orient the camera on the night, so you can plan framing and composition in advance.

FOV Simulator

The viewer overlays your framing on a live sky background. In Imaging and Smart modes you’ll see a red rectangle for the main camera. In Imaging mode you can also enable a yellow rectangle for the guide system. In Visual mode you’ll see a circle for the eyepiece’s true field.

Deep-sky targets are shown on a background sky image; solar-system targets (such as the Moon and planets) are drawn with the correct apparent size so you can see how big they will appear in your chosen setup. Use the checkboxes for the “Imaging Camera” or “Guide Camera” to show or hide overlays (Smart mode offers only the main red box; Visual offers only the TFOV circle).

What the Summary Shows

• Payload vs Capacity — Adds up the weight of your telescope, imaging camera and, if selected, guide scope/camera, then compares it to your mount’s quoted capacity. You’ll see a status such as Within safe limits, Nearing capacity, or Overloaded.
• Pixel Scale — Your sampling in arcseconds per pixel. The summary indicates whether you’re roughly under-sampled, well-matched, or over-sampled for your chosen seeing and use case.
• Guide Scale & Ratio (Imaging mode) — Shows guide sampling and the ratio between imaging and guide focal lengths (OAG and duo cameras use the main telescope focal length). Helpful for spotting combinations that are likely to chase seeing or be too insensitive to small drifts.
• Power Breakdown — Estimated watts for each part of the rig (mount tracking, imaging camera base draw, cooler %, guide camera, and other contributors where available). The cooler slider shows a range for min–max power and a “current” value for your chosen setting.
• Estimated Run-time — If a battery is selected, run-time (hours) is calculated from capacity (Wh) and your present draw (W). Mains power is treated as effectively unlimited. In Smart mode, a manufacturer run-time (when available) may also be displayed.

How the Calculations Work

Pixel Scale (arcsec/pixel)
206.265 × (pixel size in µm) ÷ (effective focal length in mm)
Effective pixel size changes with binning (e.g. 2×2 doubles pixel size).
Effective focal length = native focal length × reducer/barlow multiplier (Imaging mode).

Imaging Field of View
Horizontal ≈ 57.3 × (sensor width in mm) ÷ (effective focal length in mm)
Vertical ≈ 57.3 × (sensor height in mm) ÷ (effective focal length in mm)
The red box size on screen is these angles mapped to the current zoom level in the viewer.

Visual True Field (TFOV)
Preferred: (eyepiece field stop ÷ effective telescope focal length) × (180/π)
Fallback: apparent field of view ÷ magnification
Displayed as a circle in the viewer.

Guide Scale
Same formula as pixel scale, using the guide system’s pixel size and focal length.
With OAG/duo cameras, guide focal length = main telescope focal length; with a separate guide scope, it’s the guide scope focal length.

Guide Ratio
Imaging focal length ÷ guide focal length (imaging side includes any reducer/barlow).
Used to flag good matches versus combinations that are prone to flexure or chasing seeing.

Power & Run-time
Total watts ≈ sum of: mount (tracking), imaging camera base draw, cooler %, guide camera, and other rig loads where available.
Run-time (hours) ≈ battery watt-hours ÷ current total watts (mains = effectively unlimited).

Why It Matters

These aren’t just numbers — they help you spot issues before you spend money or head out under clear skies: is the mount overloaded, are you sampling sensibly for tonight’s seeing, is the guide setup effective, and will your battery last long enough for the session you’re planning?

By combining verified Equipment Card data with practical rules of thumb, the Rig Builder gives you both the raw figures and the context needed to make confident choices about your next rig or upgrade.