How to rotate an image without shrinking

[WS007]

I want to rotate an image, but do not want it to shrink when the border exceeds the frame. I want it to do with perfect circular images, obtained with a circular fisheye lens. Therefore the missing area outside the circular image does not matter...

[RomasBudras]

Probably you can use "Scale" and "Rotate" sliders (scale with negative values) in the "Transform" panel.

[WS007]

Thank you Budras, this works. Now I can rotate the circular image and it does not change the size ("Trans Rotate")...

But here comes the next question: The background outside the entire frame image is now white, but I want it black. How do I change the color of the background (area outside of the image) to black?

Thanks, Wolfgang

[WS007]

Here is an example - The image before rotation (the horizon is not horizontal) and after rotation (the horizin is horizontal, but the area from outside the photo is whilte):

[Conrad_C]

I don’t think Lightroom Classic has any way of affecting the white area outside the image, it isn’t an editable area. If you apply any tool such as a brush or mask, the effect stops at the end of the image. In other words, from the point of view of Lightroom Classic, there is nothing out there, nothing to edit. Lightroom Classic does not have a way to add to the image area and does not have layers like Photoshop, so there is no way to add something behind the image.

You can do it in Photoshop in 10 seconds. Send the photo from Lightroom Classic to Photoshop (Photo > Edit  In > Edit In Adobe Photoshop). In Photoshop, choose Layer > New Fill Layer > Solid Color, and set it to the color you want (black). In the Layers panel, drag the solid color fill layer down so that it’s behind the image.

When you save this new Photoshop document, it’s saved to the same folder that the base image came from, and also added to the Lightroom Classic catalog it was sent from.

[WS007]

Thank you Conrad for this precise information!

Wolfgang

[RomasBudras · Accepted solution]

LRC does not have a way to specify fill color for out of bounds area.
Besides other tools like Photoshop (as Conrad C suggested), workaround purely in LR would be to reimport the output image  (at max quality, likely TIFF) and then using masking functions change the white color to black (any tool - inverted curves, or exposure + black level to -max).