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Sigurd
03-21-2008, 02:25 AM
I'm trying to tighten up my photoshop maps and I'm running into an unacceptable level of blur.

This is what I mean:

http://wm23.inbox.com/thumbs/1e_9faa8_711d5b4_oJ.jpg.thumb

You'll notice
a) its pretty blurry
b) there is some pixelation where I tried to use the sharpen tool - just not up to the task.


Is this the bane of non vector mapping?

Any good general advice for avoiding blur?


All comment appreciated.


Sigurd

delgondahntelius
03-21-2008, 03:51 AM
is that at 72 dpi? ... that could be one of the problems... the higher the dpi, the better the resolution when you zoom in .... most of your online digital maps should be in the range of 300 dpi...

Midgardsormr
03-22-2008, 01:52 AM
DPI settings should not have any effect until it comes time to print. As long as you're displaying on the screen, the only numbers that matter are the resolution.

What steps did you go through to get your current image? If you began at a low resolution and tried to increase it, that could account for the problem. A raster image cannot be increased in size without losing sharpness.

There are some things you could do to repair the image, but they'll likely involve retracing the coastline. I think what I'd do in your position would be to use that Random Coastlines in Gimp tutorial to generate a new fractally coast.

kalmarjan
03-22-2008, 05:09 AM
DPI settings should not have any effect until it comes time to print. As long as you're displaying on the screen, the only numbers that matter are the resolution.

What steps did you go through to get your current image? If you began at a low resolution and tried to increase it, that could account for the problem. A raster image cannot be increased in size without losing sharpness.

There are some things you could do to repair the image, but they'll likely involve retracing the coastline. I think what I'd do in your position would be to use that Random Coastlines in Gimp tutorial to generate a new fractally coast.

In one respect, you are correct. DPI has no effect on what the OP is trying to do. I think the response was intended to speak about the resolution of the image when the actions we ran. If you have a higher resolution, there will be less chance of blurring.

Sandeman

StillCypher
03-22-2008, 04:00 PM
Starting with a high resolution (300 dpi) helps avoid a lot of problems. In the meantime, there's a trick you can try:

Duplicate your map layer (cuz we never work on the original!)

To the duplicated (top) layer, apply Filter>Unsharp Mask with the following settings:

Amt = 90%
Radius = 6 px
Threshold = 3 levels

Duplicate the layer you were just working on. Set the blending mode to Overlay. Go to Filter>Other>High Pass. Set at 3 pixels. Lower opacity (I set it at 75%). You can also switch the blending mode to either Soft or Hard Light -- whichever gives the best results.

Even so, this particular map looks best when reduced to about 45% of the original size... :(

pyrandon
03-22-2008, 04:22 PM
The process used to create your map could also be a problem. I remember some methods I took had this issue as well; now I rarely use blur filters--and even when I do, only in controlled areas (ex: if you select an area then blue it, only the interior space will blue, not the edges where blurring is the most noticable.)

Perhaps that helps? If you explain how you created the image maybe we can find another manner that does not rely upon blur filters, brushes, and such.