Merging Similar Colours

[Caledonian Rhyfelwyr]

I'm using Photoshop to make a heights map.

I've just about got the black outline (R1, G1, B1), and the rest to be pure white. However there are still some greyish squares. Is there any way to get these grey squares to move to either black or white? Preferably whatever is closer to the grey square in terms of colour, since most are either very nearly black or very pale grey.

Thanks for any help.

[B. Ward]

Try Image->Adjustments->Posterize and set the levels to "2"

[Serious J]

The way I do it in PS is to magic wand the bad coloured pixel with a tolerance of 0 (this selects every pixel of that specific colour), then shift + 5 to fill them in. You may need to do this a few times if there are multiple errant pixels with different rgb values.

[Argent Usher]

The way I do it in PS is to magic wand the bad coloured pixel with a tolerance of 0 (this selects every pixel of that specific colour), then shift + 5 to fill them in. You may need to do this a few times if there are multiple errant pixels with different rgb values.

Then should be working the REPLACE COLOR tool even better.
IMAGE-->ADJUSTMENT-->REPLACE COLOR

Use the eyedropper tool on your map and with ADD TO SAMPLE add step by step all color or with the fuzziness you can easily add the "Nearest Neighbor" colors.
Then change the color in the replacement section.

Regards A.U.

[B. Ward]

Yes that is also a very good way. Make sure you have "Image Interpolation" set to "Nearest Neighbor" in edit->preferences->general (ctrl + K) when mapping. This will save you alot of time and headache.