Greyscale Elevation ?

[midwestcoast 10]

Hi guys,

..so I've tried my hand at making my first few maps using the tutorials on here. The difference is that I've been importing the greyscale images into terraformer and saving them that way. I don't adjust the greyscale to make sure its above sea-level, I just use the raise terrain feature once I'm in terraformer. I've basically been able to troubleshoot things myself up until this point, heres my problem:

Elevation !? How do I make maps with high mountains and deep valleys ? The greyscale feels maxed out, the tops of my mountains are white as possible yet the elevation in-game doesn't even break into the snowzone of my terrain mod like loads of regions I've downloaded have.

Is there a way to do this without using greyscale ? Am I supposed to use the compress feature in terraformer (stretching the elevation instead of compressing it) ? I've tried that with mixed success, sometimes it looks decent but usually it makes the terrain lumpy.

Thanks for any help you can offer,

mwc

EDIT:

So I tried using the scale feature when I imported the image, and that worked wonderfully to raise the elevation in the mountains. My issue now is smoothness. The DEM data I used was 1/3 arc. When I saved the image as a GeoTiff in Microdem I had it fully zoomed in and when I resized it in photoshop the pixels went down, not up, so there shouldnt be any problems with upsizing.

^^ This is a zoom on one of the valleys, with should be relatively smooth and flat, if you look closely you can see how its not a gradual change. ^^

^^ Here's what my region looked like even after smoothing it twice. In steeper areas its meh..ok...but the valleys aren't smooth, they step up and smoothing it just makes the steps rounded instead of creating a gradual slope. I'm not sure where I'm going wrong, I don't know how I can get any smoother of an image file to work with ? Any ideas would be appreciated, I'm probably just missing something obvious.

Thanks, mwc.

  Edited February 15, 2012 by midwestcoast  

[Izidor44 112]

Hi midwestcoast,

You make me remember my first experimentations...

Please first have a look at :

New in mapmaking

Greyscale chart

Mapping experimentations

Your method using Terraformer sounds well, but I think your smoothness problem comes from your original picture definition. I think you use 8 bit images, where you have "only" 256 grey level. This stepping effect is due to the fact that the game allows an elevation value for each gray value of your image. But these values may not be consecutives.

The best way is to use Photoshop, which handle 16 bit definition standard for your images. Now, you can have more than 6500 meters of spanning, rather than 700 meters or so in 8 bit.

Hope this is helpfull

Izi

[midwestcoast 10]

Thanks a ton. I'll have to do some more experimenting. You're right about the images being 8-bit. I have been using photoshop, the problem is that they are already 8-bit when I get them into photoshop so I need to figure out how to save them in Microdem as 16-bit. At this point as soon as I convert the image to greyscale in Microdem I can see the stepping effect will happen. They were 1/3 arc maps, so I don't feel like it's the DEM quality, but maybe I'll have to try a different area and see if the same thing happens.

What format do you suggest downloading the DEM data in, saving it in, and then saving it in photoshop in ?

I've been downloading them as GeoTiff as I don't know what the other formats are. I was saving them as GeoTiffs and then saving them as a JPEG in photoshop, but changing to 16bit wont let me save as a .jpg, when I saved as a .bmp the region was super messed up.

Thanks again, mwc

  Edited February 15, 2012 by midwestcoast  

[midwestcoast 10]

UPDATE

I had some success. After messing around I got a region that wasn't toooo steppy. After a bit of smoothing it turned out quite nicely. Can't wait to try another.

[Izidor44 112]

That looks pretty well, nice one

Keep practicing and experimenting, knowing that 8 bit definition will create this stepping effect as soon as your elevation delta will be a bit high.

Hips,

Izi

[Izidor44 112]

What format do you suggest downloading the DEM data in, saving it in, and then saving it in photoshop in ?

I've been downloading them as GeoTiff as I don't know what the other formats are. I was saving them as GeoTiffs and then saving them as a JPEG in photoshop, but changing to 16bit wont let me save as a .jpg, when I saved as a .bmp the region was super messed up.

You're lucky if you already have Photoshop. Forget the JPEG format, which compresses you image and deteriorates the quality (files in jpeg are for Internet : small and fast, but ugly in details).

Convert your GeoTiff file into .png file (16 bit of course), and you'll be OK I think.

[midwestcoast 10]

What format do you suggest downloading the DEM data in, saving it in, and then saving it in photoshop in ?

I've been downloading them as GeoTiff as I don't know what the other formats are. I was saving them as GeoTiffs and then saving them as a JPEG in photoshop, but changing to 16bit wont let me save as a .jpg, when I saved as a .bmp the region was super messed up.

You're lucky if you already have Photoshop. Forget the JPEG format, which compresses you image and deteriorates the quality (files in jpeg are for Internet : small and fast, but ugly in details).

Convert your GeoTiff file into .png file (16 bit of course), and you'll be OK I think.

Right, my problem I think is that the damage is done before I even get into photoshop. If I convert to a 16 bit png, when I import to terraformer the elevation change is massive, once I compress it, it stills looks as steppy as if I used an 8 bit image. I think my problem is saving the GeoTiff in high enough quality in the first place, I can't figure anyway to do that though.

[Izidor44 112]

Hi Midwestcoast,

I've seen your recent productions, which looks quite interesting. Two questions :

- do you succeed in upgrading at a 16 bit level of definition ?

- do you plan to release map which include shoreline/river ?

Cheers,

Izi

[midwestcoast 10]

Hi Midwestcoast,

I've seen your recent productions, which looks quite interesting. Two questions :

- do you succeed in upgrading at a 16 bit level of definition ?

- do you plan to release map which include shoreline/river ?

Cheers,

Izi

I really haven't had much luck using 16 bit. When I convert to 16 bit in photoshop the image looks the exact same, with the exact same steps instead of a smooth gradient. So when I import to terraformer, 16 bit just makes the mountains HUGE, like giant spires, and once I compress them it basically looks the same as the 8 bit image. I'm not really sure what else I can do, the problem is definitely that the greyscale image I save from MicroDEM or Dem3 is already steppy and I can't 'upgrade' it after its already saved like that.

I've just been very thorough with the smoothing tool in terraformer, which works but tends to kill any smaller features at low elevation and is a bit impractical on large maps.

As far as coastlines are concerned, I've messed around with some, it shouldn't be an issue. I imagine a river might be a little more work.

[Izidor44 112]

I'm not really sure what else I can do, the problem is definitely that the greyscale image I save from MicroDEM or Dem3 is already steppy and I can't 'upgrade' it after its already saved like that.

What is your "source" file and where does it come from ? If you use 3dem, it should be possible to save your map in geotiff, then open it in PS and save it as a 16 bit PNG file...

I think you should forget MicroDem as it doesn't handle this standard.

Hips !

Izi

[midwestcoast 10]

I'm not really sure what else I can do, the problem is definitely that the greyscale image I save from MicroDEM or Dem3 is already steppy and I can't 'upgrade' it after its already saved like that.

What is your "source" file and where does it come from ? If you use 3dem, it should be possible to save your map in geotiff, then open it in PS and save it as a 16 bit PNG file...

I think you should forget MicroDem as it doesn't handle this standard.

Hips !

Izi

BREAKTHROUGH ! Well sort of.

It's definitely the DEM data itself that is causing the stepping, this wasn't obvious in MicroDEM but in 3dem at full scale, before its even converted to greyscale, it's clear as day.

So...can I ask where you get your DEM data from ?

I've been downloading from USGS Seamless Data Warehouse, mostly 1/3 arc. http://seamless.usgs.gov/website/seamless/viewer.htm I thought this was what most people are using but I suppose not ? Unless I'm somehow mangling the data between downloading and opening...

  Edited February 22, 2012 by midwestcoast  

[Izidor44 112]

So...can I ask where you get your DEM data from ?

Hi Midwestcoast,

Try this link : Earth Explorer

You need to register before downloading, and it's free.

Izi