How to Blend Two Photos Together?

[StevenC2020]

I recently migrated to Affinity from Photoshop and am still learning to translate some of my Photoshop work stream to Affinity. Most things I can Google, but it's hard to find a tutorial for blending two photos into something like the attached image. On Photoshop, I'd just create a layer mask on my selected layer before using its gradient tool to gradually fade one photo into the other. The gradient tool and layer masks on Affinity seem to work differently. Anyone know how to create a similar effect on Affinity?

[smadell]

Put one photo on top of the other in the Layers Panel. Attach a mask to the top layer. With the mask selected, add a White to Black gradient. (see below for results, as well as the Layers panel)

[smadell]

There's actually a more elegant solution, but one that is a bit convoluted. Once again, put your skyline photos one atop the other. Now, instead of creating a mask you'll draw a rectangle (use the Rectangle shape from the Tools panel) on top of the stack. Put a gradient into the middle of that rectangle, with a solid color (I used black) on both the top and bottom nodes. So far, you've got a gradient that goes from black to black, I know. But now, set the Opacity of the top node to 0%. So now you've got a gradient that is solid on the bottom and transparent on the top.

You'll take that rectangle and make it a Child Layer of the Top Skyline. You can drag the rectangle layer just beneath and to the right of the Top Skyline layer, until you see the horizontal blue line beneath the Top Skyline layer. Or, with the Rectangle at the top of the Layer stack, you can choose Move Inside from the Arrange menu.

Once the rectangle is a child of the Top Skyline, set its Blend Mode to Erase. Because it's a child of the Top Skyline, the blend mode will ONLY act on that layer. And the Erase will only erase the part of the Top Skyline layer that contains visible pixels (that is, the bottom portion of the Top Skyline layer).

The nice part about doing it this way is that the Gradient remains editable, and can be repositioned at will at any time.

[StevenC2020]

Thanks! That was really helpful. I tried the more elegant technique, but couldn't figure out how to turn the rectangle into a child layer. Was I supposed to use the rectangular marquee tool for that?

In any case, I used the first technique to create the photo below. I think it's workable, although there's a bit of an unrealistic blue tinge to the clouds in the middle right. This is a different kind of blend than the skylines I posted in the first photo, though, so I guess it's a bound to be a bit messier. It might actually be resolved if I figured out the rectangular tool in the second solution you posed, since that might leave the original layer unaffected and free to extract additional layers from to cover these blemishes. 

[smadell]

This is the "elegant" version. Watch...