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    Default Height map elevation variance

    Hello. I'm currently working on my first project (a map of Middle-Earth) using the "difference-clouds height map"method. My project is pretty big (60*90 cm @ 300 ppi) and while I have an overall satisfactory result for my heightmap (having painted in lower areas, plains etc) I have a problem with the main mountain ranges. I tried darkening the overall heightmap and going a lot lighter on those mountain ranges (the only places I went up to full white) but still when I render it with lighting, they not so luch pop out as huge, massive chains of mountains, but more like broad areas of very rugged land, not a lot higher than the surrounding lands.
    I'd upload a picture but I'm writing from my cellphone right now, I hope you understand what I mean.
    Is there any way to make mountains at that scope pop out more, am I doing something wrong or is the problem inherent to the method I use?

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    Software Dev/Rep Redrobes's Avatar
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    Just out of interest and since I am one of the members, are you aware of the MEDem project ?

    http://www.cartographersguild.com/ge...roject-11.html

    Middle-Earth DEM Project in Outerra - YouTube
    Last edited by Redrobes; 09-06-2013 at 08:49 AM.

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    Default Re: Height map elevation variance

    Quote Originally Posted by Redrobes View Post
    Just out of interest and since I am one of the members, are you aware of the MEDem project ?

    http://www.cartographersguild.com/ge...roject-11.html

    Middle-Earth DEM Project in Outerra - YouTube
    I was vaguely aware of such a project but I have to admit I haven't taken the time to explore it yet. I'm making my map mainly for personal pleasure. I'm working with the Wynn-Fonstad Atlas for Reference, mainly.
    As I said, getting the mountain ranges right is my main problem so far...

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    Guild Master Gracious Donor Midgardsormr's Avatar
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    If your peaks are set at 1, or nearly so, what is the value of a pixel representing a lowland area? The relationship between value and elevation in a heightmap is linear, so if you want your highest peaks to be 20,000 feet (255), and the Shire at maybe 3,000 feet, then the value of a pixel in the Shire is only ~38. In floating point space (running from 0 - 1), it's only .066.

    What bit depth are you working at? 8-bit gives you only 256 values, which is really not enough to describe the difference between mountain peak and lowlands, at least not if you want a decent amount of detail in the lows. Unfortunately, Photoshop disables a lot of tools in 32-bit mode, so it isn't easy to use.

    Something you might try is to run the Lighting Effects on the mountains and lowlands separately. Set up a layer where 0 is around 4,000 feet or so and use your entire range to just put detail in the mountains. Then you can use the full range to get plenty of detail in your lowlands, too, and from there it becomes a matter of finding a way to blend the two layers together.
    Bryan Ray, visual effects artist
    http://www.bryanray.name

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    Default Re: Height map elevation variance

    Quote Originally Posted by Midgardsormr View Post

    Something you might try is to run the Lighting Effects on the mountains and lowlands separately. Set up a layer where 0 is around 4,000 feet or so and use your entire range to just put detail in the mountains. Then you can use the full range to get plenty of detail in your lowlands, too, and from there it becomes a matter of finding a way to blend the two layers together.
    Oh never thought of that. I'll see if I can figure something out along those lines...


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    Default Re: Height map elevation variance

    Quote Originally Posted by Olvyr View Post
    I'd upload a picture but I'm writing from my cellphone right now, I hope you understand what I mean.

    Sent from my GT-N7000 using Tapatalk 4

    Here's what I got so far (just for demonstration purposes)
    before any attempts of improvement.




    Sent from my GT-N7000 using Tapatalk 4

  7. #7
    Guild Master Gracious Donor Midgardsormr's Avatar
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    You may wish to use the directional light instead of a spotlight in order to keep even lighting across the entire map.
    Bryan Ray, visual effects artist
    http://www.bryanray.name

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    Guild Adept Gracious Donor lostatsea's Avatar
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    Not knowing the exact values you are working with. One thing you can try is to decrease the overall brightness to 60 to 70 % using adjustment ( brightness contrast) then use Adjustment (Levels); Push the White slider over to the left till it touches the edge. This will Force the contrast in the "HIGH" end of the bump. If you go with Midgardsormr suggestion of doing the areas separately then to blend set the mountains above the low lands and use levels to push the blacks up to turn all the darker greys to black ( may need to adjust the grey slider to preserve your "HIGH Areas" then set the Blend Mode to Screen to blend the dark areas of the Top Mountain layer into the Mid range of the Lowlands level below ! Directional is the way to go for more realistic Shadows. I learned that late last month !
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    For my personal experience in working in similar (though not identical) ways, I would concur with Midgardsormr in that you should use two (or more) layers to do the elevation. Multiplying the layers is the only way I found to be able to get both details and stand-out peaks.

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    Default Re: Height map elevation variance

    Quote Originally Posted by feanaaro View Post
    For my personal experience in working in similar (though not identical) ways, I would concur with Midgardsormr in that you should use two (or more) layers to do the elevation. Multiplying the layers is the only way I found to be able to get both details and stand-out peaks.
    Thank you all so far for your comments. I'll try this once I have a couple of hours to do so undisturbed...

    Sent from my GT-N7000 using Tapatalk 4

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