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View Full Version : How Do I Make Close Up Maps From An Area Map



Thesslian
01-25-2012, 10:39 AM
That is probably phrased pretty badly. Here is what I am thinking. If I make a map of say, I chain of islands and then want to make more detailed maps of each island in the chain, is there a good way to get the shape of each island and enlarge it without losing all of the image quality? I was trying to figure out how to do it with the paths, but that way seems to either be sloppy if I try to make a path a selection or tedious by having to manually click around the landmass a thousand times. I also have no idea how to scale a path or import it into a new file. I'm sure one of you wizards knows how to do this, or if the process should be done the other way around by making the detailed maps then shrinking them down and merging them together.

Langy
01-25-2012, 12:03 PM
One way to go about it is to go the other way around - make the detailed maps first, then the overview map (your last suggestion). Unfortunately, I know of no easy way to expand a map and keep that level of detail, unless it's a vector map, in which case it's trivial (vectors being resolution-independent).

ScotlandTom
01-25-2012, 12:19 PM
I was actually planning on doing this exact thing with the world map I'm working with, Thesslian. I've got a world map and now I've got to go in and create the regional maps, but I'd like to use the world map as a base. Sadly, because I didn't draw the world map in a program like Illustrator I know that when I enlarge a portion of the world map I'll be faced with a lot of blurry pixellation that I'll have to correct. My plan was to simply used the enlarged image from the world map as a base and flat out re-draw all the contours at the new resolution. No matter what approach I take I imagine it will be quite tedious, and I'm not sure there's any way to avoid that.

jfrazierjr
01-25-2012, 12:49 PM
Well... not sure if this is what you mean or not, but in GIMP, I would first and foremost make sure your landmass shapes had their own layer, ie, just the outlines(even if you don't "paint" the outlines on the finished map). Do a selection OUTSIDE the lines inside area, invert the selection, and make that a path. Now that you have the path, go to the paths "tab" and export. In your new image (which is best to be a multiple of the existing one... at least to start) on the paths tab, import and set to scale to fit image(which is why we want the new image a multiple of the previous one), then path to selection and stroke the selection. Now you have enlarged your original and maintained shapes. Note that very small things in the original might be missed by the selection process, so you may have to play with it some to get the selection "just right"

razcor
01-25-2012, 01:10 PM
If I understand the problem, what I would do, using photshop is:

- select the shape of, for example, the island you wish to enlarge;

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- select it and copy it to a new layer;

- use free transform (CTRL - T), say to 500% on both axis, this enlarge your isle;

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- select the shape, fill in white, select inverse fill in black

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- create a new layer, filter -> clouds -> render clouds (make sure foreground color is black and background is white hitting D);

- create new fill layer - threshold, adjust until you have something like this (on the cloud filtered layer adjust the opacity too see the shape of the island);

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- on the cloud filtered layer paint in black or white whith a soft, low opacity;

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- on the cloud filtered layer copy merged and then paste on another layer (or another file)


hope that answers your question...

Thesslian
01-25-2012, 05:36 PM
Ok, thanks for all the help. I think I have figured out how to do it. Here is the process I used. I took a map I had made using the Saderan tutorial that one of the land layer masks on it and used that to make a selection of all the land. Then I used quick mask to get rid of all the islands I didn't want. I made a new layer and filled the selection of the island I wanted with white. Then I made a new document with the proportions I wanted. I went back the the original map, clicked duplicate layer and changed the document to the new map I wanted to make. Then I used free transform to increase the size of the island about 950% since 1000% wouldn't fit. The edges look a bit blurry after this so I apply a smart sharpen filter at 500% and about 12 px. It gives a good result.

Hai-Etlik
01-25-2012, 11:40 PM
One way to go about it is to go the other way around - make the detailed maps first, then the overview map (your last suggestion). Unfortunately, I know of no easy way to expand a map and keep that level of detail, unless it's a vector map, in which case it's trivial (vectors being resolution-independent).

Vector graphics can't make detail appear by magic. A zoomed in vector map isn't going to display any detail that wasn't in the original. It's just that it won't have any aliasing from resampling as you would when scaling a raster image. Inkscape does have a handy tool called "fractalize" that can add some fractal noise to a path though.

RobA
01-26-2012, 12:01 AM
With the risk of seeming old here is my quick tut from 2008 very similar to razcor's suggestion http://www.cartographersguild.com/showthread.php?1397-Award-Winner-Technique-for-adding-coastal-detail-as-you-zoom-in.

-RobA>