straightening multiple images

I believe Transform > Auto with Constrain Crop uses the same algorithm as Crop > Auto and should give the same results. An advantage to using Transform > Auto is it avoids the need to use Auto Sync, which is dangerous.

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If your batch of images all have an obvious straight line, (eg. straight horizon, or even verticals), then you could try [Auto].

1. Select the multiple photos in the Develop module Filmstrip

2. Switch on [AutoSync]

3. Open the Crop Tool  [R]

4. Click [Auto]

5. Switch OFF [AutoSync]

You would still need a visual scan of the photos to check if 'Auto' did the job correctly!

It worked for me with five ocean views that were crooked camera scans.

Clicking Auto in Develop's Transform panel will attempt to automatically align the photo to be "upright".  Sometimes it works well, sometimes not.

You can copy the Transform > Auto setting from the current photo to a batch of currently selected photos using Settings > Copy/Paste Settings or Sync. Make sure you check just the Upright Mode checkbox and nothing else.

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