William Overington

I do not see anything in the file that looks like a sun or has r=224, g=224, b=0 color values. There is a sort of spiral curve shape in the top group, but it is easily selected so its bounding box shows, & its colors are r=255, g=0, b=211 so it is unclear what sun shape you mean.  It might help if you labeled everything in the layers panel & re-uploaded the file.
There also seems to be a superfluous double group for the tree(?).

It could be used as a demonstration model with a torch.
William
 

Yes it would, William. But the angle of the gnomon and the position of the hours will depend on your latitude and the direction the wall is facing. This one is about 53 degrees north and facing a little off south.) There are websites that can give you the information and some will explain how to work it out yourself.

I found a pic of a wall-mounted sundial at Norbury Manor in Derbyshire in my old photos. (It's a National Trust property, and open to visitors from time to time.) It was erected as a memorial to (I think) the former owner, who died in 1987. I've changed all the inscriptions in the foolish hope of looking clever.

 
The base colour is 45/38/71 in HSL . . .

and I found a grungy texture in my collection (this is a reduced copy) . . .

and after some playing about, I found an opacity or 25% and a blend mode Colour Burn gave me a pleasing marble-like effect.
For the incised text, I darkened the fill slightly and applied an Inner Bevel/Emboss FX using the first (triangular) profile, inverted. I adjusted the radius till the bevels met in the middle, making the letters look as though they'd been carved.

Thank you, Dan.
William
 

Thanks for providing that for me!
I'd personally recommend using Affinity Photo for this, as it contains more image manipulation and selection tools than Affinity Designer, making background removal easier in Photo.
These are the steps I've taken with your image:
File > Open and select the Image Ensure the Layer is selected in the Layers Studio and is a '(Pixel)' layer.
If this is not a (Pixel) layer, right-click the layer and select Rasterise. Select the Selection Brush Tool from the left hand toolbar On the Context Toolbar, enable Snap to edges and Soft edges Using the tool, 'Paint' over the subject to create your selection. You can increase/decrease the brush size for finer areas, or use the ALT key to 'subtract' from your created selection area. Once happy with the 'marching ants' selection around the subject, select Refine on the Context Toolbar Using the Refine brush, paint along the edge of your selection where required, this will attempt to refine the selection further, based on the edgesin the image. Once complete, select Apply in the Refine dialog. You should now have a refined 'marching ants' selection around the subject. With this active, use Edit > Cut or CTRL + X. Now, use Edit > Paste or CTRL + V to paste this to a new layer. Navigate to Select > Deselect to remove this 'marching ants' section In the Layers Studio, delete the original 'Background' layer. You should now find the subject remains, with a transparent background around her. Using File > Export, export this to PNG using the PNG preset. This will save the transparency in the PNG file.
You can now use this image in other documents, introducing it to the canvas with File > Place, and you should find only the subject can be seen, with transparent areas around her. I've attached a quick screen recording showing this workflow below, alongside a copy of the .afphoto file saved with 'History', allowing you to Undo through the steps I took in the file.
2024-01-24 17-57-57.mp4  
lady_000.afphoto
I hope this helps get you up and running with your composite design 

Here is a designer V1 document Lady.afdesign with your photo placed and rotated to prove a point. 
If you export the selection unrotated the JPG has no transparency so will not show any transparency in the exported file.
I have rotated it and exported the Selection Only, as a PNG and you will see the preview for the PNG shows transparency where you would expect even though this file has not got a transparent background. The exported result is Lady.png (attached)
I then imported that exported file Lady.png into Lady.afdesign to prove it worked.

 
Lady.afdesign

well it will export as PNG, but nothing in that is transparent so RGB 24 bit and RGBA 32 bit will look identical. What do you expect to be transparent?

Yes, Affinity V1 and V2 apps are exactly the same in this regard - provided the file being exported contains any transparency, the PNG will be exported as 32bit automatically.
Are you able to provide a copy of this picture, or your Affinity document so we can advise further?
There are many different ways to remove a background, so it's easiest if we can see where you are currently, and if you can provide a rough idea of what you may be hoping to achieve? 

In Designer (1/2) you can go to Document Setup and on the Colour tab set Transparent background. I think that makes exported PNGs have a transparent background to achieve what you want.
Other than exporting "Selection Only" there is no easy way to export a document that does not have an obvious transparent background as RGBA , as the "paper" (or artboard) is drawn to the file first for Export -> "Selection Area" and also for Export -> "Whole Document"

When exporting to PNG from Affinity, the file will be automatically created as a 24bit PNG, if no transparency is present.
If you want to export from Affinity to a 32bit PNG, simply add any transparency to your document and this will be automatically created as a 32bit PNG.
Unfortunately there's no dedicated option to export a 32bit PNG file without transparency from Affinity at this time.
This has been recently raised and discussed further here -
I hope this helps  

As long as you mean 32-bit rather than 24-bit, yes, the Affinity applications can do that.

Hi @William Overington,
I can confirm that 24 bit PNG files with transparency aren't possible to create in Affinity, and I believe this is also true in most other applications.
A 24bit PNG image supports 3 colour channels, consisting of 8bits each - Red, Green & Blue (R,G,B).
The 4th channel that a PNG can support is the Alpha channel (A), which is required for exporting a PNG with transparency present. This creates a 32bit PNG image with R,G,B,A channels.
Therefore to create a 24bit PNG image with transparency present, you would have only 2 colour channels maximum in the file, ie R,G,A or G,B,A etc.
I hope this clears things up!

https://en.wikipedia.org/wiki/Color_depth

No, you could have left them in situ so that they would be available for lining up the new versions correctly via snapping, after which you could have deleted them (or merely hidden them).

For the same result with less work, break and adjust the first ellipse and then create duplicates from there.

You could use the ‘reduction linocut’ process to create a multi-layer print, but that would be a tedious and unforgiving method!

I used Affinity Designer.
I used the Transform panel to accurately place the wheels, setting the numbers to be centred on the centre spot of the lower edge of the bounding box, so that the wheels each sat on the (unshown) rails.
I made the body of the locomotive by starting with an ellipse, converting to curves, then I used the node tool to delete the lower centre point, then I made the two end points to become sharp corners. Then I added a point to make the back of the tender. I lined everything up using numbers entered into the Transform panel.
I made the smoke from ellipses, gradually making them bigger and longer to try to show that the locomotive is running at speed and that the smoke dissipates, then using various levels of opacity to indicate the dissipation of the smoke.
I realize that doing the smoke that way could not, as far as I know, be done with a real linocut, so I am thinking of trying to have another version where the smoke dissipation is done with white swirls that gradually have thinner white lines farther apart.
I made the wheels first, then lowered the body of the locomotive all in one piece onto them after designing it further up the canvas. I grouped it all, then I added the black rectangle and moved it to the back then I coloured the locomotive and its smoke white.
As I drew the picture I saved what I had done in case I made a mistake and had to go back.
William
 

I used the mechanical pencil H4 from the Pencil brushes with a high width. If I want some parts thinner, I used the eraser also set on mechanical pencil so that the outer line of the branch is not strait. 

At first I make a sketch with a basic brush, than I paint the bird, with a lot off layers so if I’m not content I can delete just that layer or use a different color to see what is best. For details I make a new group and again a lot of layers. I use a lot of different brushes. For finetuning I use the smudge brush. The background is always the last layer I make. During the painting my background is only one color. And no, I don’t use gradient. 
 

The beauty of having layers is that you can choose the order in which you do these things! You could draw the bird first and then add the background layer, or you could start with the background and add the blue tit on top (and then, if desired, go back to the background layer and make it completely different).

With Affinity Photo V2 on iPad Pro and Pencil.

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("using" in that sentence means adding to or changing in a significant or non-obvious, novel or interesting way that others may appreciate) 
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