Linear image

Crop tool

Removes the ragged stacking edges; can also rotate or flip.

How to use it

The COSMO window, recorded while the settings are moved.
  1. Open Tools and click the tool: it is added after the selected step.
  2. Move its settings: the image follows as you move them (Live preview).
  3. Press Apply to keep the result. Before / after compares at any time.

Drag the frame or its corners on the image.

Settings

Aspect ratio
Free, Original, 1:1, 4:3, 3:2, 16:9 and their portrait forms.
Trim edges
2, 5, 10 or 15 %: removes that much on each side.
Orientation
Quarter turns, half turn, horizontal and vertical flip.
Whole frame
Puts the frame back on the whole image.

When to use it

First, before anything else: the ragged edges left by stacking mislead every tool that follows.

Image

Works on a linear or a stretched image.

Example

cropped whole stack whole stackcropped
M 42 stack: the ragged edges left by stacking are removed. Image taken with a Seestar S50 Pro.