Can I crop a layer without cropping the whole document?

[AntiqueFlaneur]

I've got an image in Affinity photo that has to be 1280 x 720.

There's a background layer that's black, a text layer, and an image/foreground layer. 

I need to crop the image/foreground layer to eliminate about a third of the image. When I use the crop tool with the correct layer highlighted and the other layers turned off (unchecked) to do this, it cuts out the desired part of the image, but in doing so it reduces the dimensions as a whole, thus making it unusable. 

How can I just crop one layer without affecting the image as a whole?

[Alfred]

14 minutes ago, AntiqueFlaneur said:

How can I just crop one layer without affecting the image as a whole?

Create a rectangle of the appropriate size and position it as required. Go to the Layers panel, drag the rectangle layer and drop it onto the thumbnail of the layer you want to crop.

[AntiqueFlaneur]

If I've tried to do as you suggest.This seems to blocked the image entirely, like the first screenshot below. 

If I place the rectangle layer directly below the image's layer, it blocks the part of the image that I want to preserve, but shows the rest. As in the second screenshot below. 

What am I missing?

[Pšenda]

33 minutes ago, AntiqueFlaneur said:

What am I missing?

See Clipping:

https://affinity.help/photo/en-US.lproj/pages/LayerOperations/clipping.html

[Alfred]

34 minutes ago, AntiqueFlaneur said:

What am I missing?

It looks as though you’re trying to use a rectangular selection instead of a rectangle. Expand the Shape Tools flyout (showing the Ellipse Tool in your screenshots) and choose the Rectangle Tool, and then draw a rectangle over the part of the ‘Foreground’ Pixel layer that you want to crop. In the Layers panel, drag the rectangle layer and drop it on the thumbnail of the picture layer as I described earlier.

[AntiqueFlaneur]

7 minutes ago, Alfred said:

It looks as though you’re trying to use a rectangular selection instead of a rectangle. Expand the Shape Tools flyout (showing the Ellipse Tool in your screenshots) and choose the Rectangle Tool, and then draw a rectangle over the part of the ‘Foreground’ Pixel layer that you want to crop. In the Layers panel, drag the rectangle layer and drop it on the thumbnail of the picture layer as I described earlier.

Totally missed that distinction! The rectangle tool did work. Thanks so much for your help~ 

[carl123]

11 hours ago, AntiqueFlaneur said:

How can I just crop one layer without affecting the image as a whole?

I think you also have Publisher?

If so, then choose File > Edit in Publisher and the crop tool there will work on a single layer

When done, just choose File > Edit in Photo to go back to APhoto