How would you do a weather map?

[Dragonspit Ben]

Hello everyone!

How would you guys use GIMP to make a weather map with radar, like this one?:

https://blogger.googleusercontent.com/im...em_bow.png



Specifically, how would you get that pixelated look for the storm system? I don't want it to look too smooth or clean.

Thank you everyone!

[rich2005]

(03-18-2025, 06:01 PM)Dragonspit Ben Wrote: Hello everyone!

How would you guys use GIMP to make a weather map with radar.....snip.....

Specifically, how would you get that pixelated look for the storm system? I don't want it to look too smooth or clean.

Obviously a lot of work involved, with overlays etc, however the effect is called dithering, usually associated with an indexed mode image.

You might get an individual layer dithered like this
(1) In a transparent layer, paint in your coloured shape.
(2) Give it a blur Filters -> Blur -> Gaussian blur
(3) I can not find the Dither in the menu structure   but it is there. Use the Gimp search - the /(?) key - and enter dither as the search reference. Click on the entry to start the Dither filter. 
EDIT: Dither is down near the bottom of the Colors Menu
(4) Reduce the Alpha levels right down to zero and experiment with the Dithering method options.
----
New layer, new colour, repeat procedure.

   

[Tas_mania]

To me the question is like 'how do I reproduce a complex x-ray image of a persons spinal column'?  Or maybe a cat scan of their brain?

Usually weather bureaus are government departments that are actually funded and owned by you the taxpayer.

I like doing screen grabs of extreme weather events and I do collect them.

   

I just take a screengrab of a radar weather image with a completely clear conscience.

[Dragonspit Ben]

(03-19-2025, 06:36 AM)Tas_mania Wrote: To me the question is like 'how do I reproduce a complex x-ray image of a persons spinal column'?  Or maybe a cat scan of their brain?

Usually weather bureaus are government departments that are actually funded and owned by you the taxpayer.

I like doing screen grabs of extreme weather events and I do collect them.



I just take a screengrab of a radar weather image with a completely clear conscience.

I agree completely but I need something original and specific. It's for a frame in a comic book, the newscaster is standing in front of a weathermap describing specific weather conditions.

But yeah the image is exactly the pixelated look I'm looking for LOL

[Tas_mania]

I made one with ChatGPT as an experiment  

   

I needed to log-in to make images. Looks like your radar image needs to be for one city? The AI images are good quality and need to be pixellated.

[Dragonspit Ben]

(03-18-2025, 07:07 PM)rich2005 Wrote:

(03-18-2025, 06:01 PM)Dragonspit Ben Wrote: Hello everyone!

How would you guys use GIMP to make a weather map with radar.....snip.....

Specifically, how would you get that pixelated look for the storm system? I don't want it to look too smooth or clean.

Obviously a lot of work involved, with overlays etc, however the effect is called dithering, usually associated with an indexed mode image.

You might get an individual layer dithered like this
(1) In a transparent layer, paint in your coloured shape.
(2) Give it a blur Filters -> Blur -> Gaussian blur
(3) I can not find the Dither in the menu structure   but it is there. Use the Gimp search - the /(?) key - and enter dither as the search reference. Click on the entry to start the Dither filter. 
EDIT: Dither is down near the bottom of the Colors Menu
(4) Reduce the Alpha levels right down to zero and experiment with the Dithering method options.
----
New layer, new colour, repeat procedure.

I keep trying this but it doesn't work for some reason. Am I missing something?

[Dragonspit Ben]

BUMP!

---

Anybody here???

[rich2005]

Nope - everybody gone home.

This a very quick test using painted in layers - a fuzzy brush to give some edge fade. Then dithered.

   

...but to get anything half decent, it is going to be a lot of detail work. You might have a look around for a "scatter" type brush rather than using the Dither filter.

[rich2005]

Maybe try this, a Gimp brush dither.gih (gimp image hose - an animated brush) this is just pixel dots scattered around and it might get you your "distressed" edges.

Use the pencil tool to keep the hard  edges. Unzip the attached, put dither.gih in your brushes folder, Refresh brushes or restart Gimp.

Another quick example.   https://i.imgur.com/c5M46Hy.mp4

[Tas_mania]

I got a radar image, free selected the cloud on it and used Filters > Blur > Pixelize.

Use low values for 'block width' or too blocky.