Telescope Collimation Lab

Keep the photo.
Measure the centers.

A star-test record with the image, marked geometry and before/after context kept together.

US$4.99 once. No subscription, ads or in-app purchases. Regional prices vary.

View on the App Store

Preview of the prepared 1.1 update. The App Store shows the currently released version.

Actual iPad app showing a manually marked synthetic ring photo beside its measured image-plane offset
Source and geometry side by side. The optional ring study is synthetic, not an observed star or an optical simulation.

Mark

Import a still PNG or JPEG. Place the reference ring center, inner-feature center and ring edge. Fine-adjust with X/Y values, one-pixel nudges and undo.

Compare

Choose two rounds and compare their marked centering percentages. Keep focus, orientation, image scale and the chosen ring consistent.

Keep

Retain original photo bytes and checksums. Export annotated PNGs, a complete-round PDF, CSV, restorable JSON and a source-bearing ZIP.

Real manual point-placement editor with ring-center, inner-center and ring-edge controls
Explicit placement. No automatic ring detection or invented default measurement.
Real iOS preview of the exported centering PDF
A real PDF record, with geometry and source evidence for each round.

Compare a record, without inventing a pass.

Image direction is clockwise from right, with positive Y down. A smaller marked offset alone does not establish collimation. This app does not calculate physical screw turns, certify optics or replace your telescope maker’s procedure.

Actual iPad comparison of two explicitly synthetic photo measurements
The optional teaching study demonstrates a change in manual image-plane geometry.

Support

Read the format and recovery guide, or email maga40@naver.com.

Stored on your device

No account, analytics, tracking or developer upload. You choose imports and sharing. Device and cloud-provider backups follow your system settings.

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