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I have an image with a picture and a caption. I'd like to rotate the entire image so that the caption is perfectly horizontal. Is there a way to do this other than by eye?

First I pull down a couple of horizontal guidelines.  Then I use layer - transform -arbitrary rotation and then click and drag the layer to the angle that matches the guideline.

(08-11-2022, 03:04 AM)devinl Wrote: [ -> ]I have an image with a picture and a caption. I'd like to rotate the entire image so that the caption is perfectly horizontal. Is there a way to do this other than by eye?

This is done with.... the Measure tool ()(*).

Use the tool to measure the angle of the baseline of the text. For accuracy, you do a first pass where you roughly position the two ends, and then zoom on each end to adjust it (if you click close enough to the end points, you can move them without restarting a new measure). Use the base of the characters with "legs" (m, x, w, k here) and avoid those with rounded bottoms that usually extend slightly beyond the baseline.


Once this is done hit the Straighten button in the measure tool options. This will rotate the layer so that whatever you measured becomes exactly horizontal.

Note that if you are working on photos you can have more problems than just rotations (perspective due to camera misalignment, etc...).


(*) Technically you can also do it with the Rotate tool () used in "corrective" mode, bu the Measure tool is more practical.

ninja'd by ofnuts while making screenshots, however
First of all, if the caption is embedded in the image, that is, image+text = single layer Whatever you use rotates the whole image. 

1. Using the measure tool. Draw in along the text. Click the straighten button. It is fairly smart, the drawn in line vertical for buildings etc.

[attachment=8483]

2. The rotate tool in Corrective Mode. Set some guides from the tool options. Click in the image, drag-rotate the guides to match the caption. Apply.

[attachment=8484]

Super excellent techniques - thank you!