View Full Version : Coastline Question

01-24-2011, 09:39 PM
There was a way in photoshop, using something to do with posterize to get those lovely jaggy coastlines... but I totally forget how to do it.

Does anyone know what I am talking about?


01-24-2011, 10:20 PM
Not sure about a method using posterize, but Ascension has a quite workable method at the beginning of his Atlas-style tutorial. Basically it's a noise layer with a hard-mix layer on top that you paint onto with a soft low-opacity brush, if I remember correctly.

01-24-2011, 10:21 PM
Yeah that technique doesn't work as well for what I am looking for... for the life of me I can't remember how to do the one. It might have been a trick that Coyotemax showed me... damn I miss him :(

01-24-2011, 10:23 PM
Ahh ... well if you feel like slumming around in Gimp, OldGuy's coast method is fantastic for the really jaggy coastlines.

01-24-2011, 10:31 PM
I can't recall the posterize filter in any of the tuts off the top of my head...not to say that it isn't there just that I don't recall. The only tut that I haven't done is the Jezelf tut so maybe it's there.

01-24-2011, 10:35 PM
Well for example, your one of using the Colour Range, I must be doing something wrong, since I have white land, black sea, I tried it as seperate layers, nothing and then as a merged layer and again nothing.

I remember CM showing me a trick using Posterize, but like I say, can't remember it at all. :(

01-25-2011, 12:20 AM
Try one of Jezelf's Tutorials, I believe I remember seeing him use his Alpha layer (with Rivers) and did a posterize to blur it way out and to get definition to the rivers...

Here (http://www.cartographersguild.com/showthread.php?2557-Award-Winner-Making-maps-in-Photoshop)

This might help out but I can't recall any other tutorials using the filter but Jezelf... "4 ways to give your map a relief using height maps - using Wilbur for one of them."

But that might be Poster Edges... eh I can't remember

01-25-2011, 11:08 PM
Alas that wasn't it either.

Le sigh... this is going to task me until I figure it out.


01-26-2011, 05:06 AM
Eh.. I remember only vaguely. It was probably based on ths: http://psd.tutsplus.com/tutorials/tutorials-effects/how-to-create-an-old-world-map-in-photoshop/

01-27-2011, 08:13 AM
Nope that's not it either.


All I can remember was that it was the way to jaggy up the coasts real good! I mean small round islands would turn into jaggy pseudo rectangles with way more points, etc...

Nothing I try is working... the whole Color Select/Fuzziness thing doesn't do anything, so I must be doing that wrong.

You had shown me a way to use posterize to do it, but the above tutorial isn't helping either.

This is so bloody frustrating.


01-27-2011, 08:42 AM
Oldguys tutorial (already mentioned by Gidde, but it works just as well in photoshop - in fact I think the tutorial is written for PS) is the quickest and most controllable method I've yet seen to fractalise a coastline.

If you want to use the posterise command, try this: Draw a blobby coastline, use a grunge brush (set to black) and grunge up the edges. Posterise and drag the slider all the way to the left to a value of 2 levels (black and white).

01-27-2011, 02:46 PM
Ravells, That looks pretty darn simple and effective. Thanks!

01-27-2011, 07:56 PM
Well Threshold can do the same thing really, if you are just doing black and white, and with threshold you can adjust how much you want to be white and black for the most part...

01-27-2011, 09:59 PM
Okay by total accident, while looking for ways to do it, I had a flash of memory.

With the Black and White on one layer (water black, land white) Filter -> Pixelate -> Crystalize

I can't remember the numbers but I think you do it three times, one at 10, one at 5 and one at 3... or one at 13, one at 6 and one at 4.

After that Posterize (4) I think.

Then delete the black, clean up your coasts for phantom inlets and such and Bob's Your Uncle!

Okay, thanks for putting up with that trip through my insanity :)

01-28-2011, 03:33 AM
Glad you got there in the end!

01-28-2011, 08:15 AM
The pixellate-crystallize thing can be done with any numbers you want as many times as you want. I just started doing it at 10, 5, and 3 as an example...sometimes I do it at 25, 12, 6, and 3 when I really want to break things up. I don't use the posterize afterward, though - I use noise-median to smooth some pointy bits down a little bit.