If I understand this correctly and you use 1px size brush, then that is indeed the problem. 1px brush will not have smooth edges, because there is no "room" for anti-aliasing of a brush.
I tend to use at least 3px size brush for lines. However I know that for icons on my maps it is too small. They do not look so good. I suggest using 3-5px sized brush for line work.
If it looks too thick, make the canvas along with the map bigger and then shrink the final image. It will look better.
If you ask about my maps, I do A2 or A3 at 300dpi (I never go higher than 300 dpi). It means that in theory I can print the map in good quality but it will be 3x smaller. In reality in can be printed 2x smaller and it still looks perfect. Digitally those 300dpi does not matter.
If you ask about the digital 3x bigger canvas, I cannot be sure how other do it, but I believe that they just make maps at their screen dpi or just round it too 100dpi (most screens have now 96dpi. Some older have 72dpi if i recall correctly).
So if an artist intents do make 3000 x 2000px digital map as a final product, they will multiply that x3, make canvas 9000 x 4000px at 100dpi. Then draw the map with bigger brushes and when it done shrink it 3x to 3000 x 2000px.
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Thanks a lot for your answer !
As i see now, the problem is that I always start my maps (often A4, 300 dpi) with 4-6 pixel brushes, but as I go along, I add details, or I create thumbnails in which I try to draw cities, for example, and in these thumbnails, I often end up with 1 pixel brushes... Or in the details I want to add to the map: 1 pixel brushes.
I used to think that I was starting off on the wrong foot, with map sizes or resolutions that weren't big enough, but thanks to your answer, I've realised that it's a question of process: I need to define the elements I want to put in my map better from the outset... So, for example, I could draw the thumbnails at a good size, before ending up having to draw inside them with 1 pixel brushes.
I've also understood your explanation for drawing a map with the same resolution as the screen and reducing the size by a factor of three once the drawing's finished. I think I'll try that, at least for one map, to see what it does. In any case, thank you very much for these clarifications, they'll help me get off to a good start!
I would refrain from using 1px brush. Instead use the pressure sensitivity and draw subtle lines using 3px brush or at least 2px.
A good idea is to zoom out canvas while drawing and constantly checking the "end result". That way you can see and experiment, either increase or decrease details.
Or, if you have two monitors, draw in 100% zoom using your main monitor, and put a copy of the image on the second monitor smaller to have a live update of what the image will look like.
I was looking for a good example to show you but i could not find the one i saw few month ago, so have a look at that one by Sheather888 on DeviantArt.
If you click 2x to have the original size you can see the tree trunks have very very crude strokes (the colour, shade and highlight) as well as foliage is just a grungy brush stamped here and there. It does not look good. However, when you zoom it out, everything coalesce nicely into one big forest.
New Horizons
Fantasy maps and illustrations.
All my non-commisioned maps are FREE for personal use. Get them at my home page New Horizons
Get more of my maps by becoming my Patreon.
Support:
Patreon | Tip via PayPal.Me | Buy Me a Coffee