View Full Version : Emulating the GIMP 'Spread' Filter in Photoshop

02-08-2008, 02:13 PM
Although, on the whole, I prefer Adobe Photoshop to the GIMP(should, given the cost-differential), there are a few functions in GIMP that seem to be missing in Photoshop. This is the first in a series of short essays on methods I have found to work around some of these seeming deficiencies in PS. Although they are a bit more complicated than their GIMP equivalents, it shouldn't be too much trouble to store them as actions. Let's start the show...

1) Start by creating a new document. In order to save myself a bit of sanity, I'm going to create mine in greyscale with a black background.

2)On top of your background, create a new layer with a dissolve blend mode and an opacity of 100%(Actually you can vary the opacity if you wish). Fill this layer with white. Now, ain't that purty(?)... No, not so much, yet.

3)Now, create a layer mask on that top layer. Make sure you have the mask selected, and invert it to black.

4)Paint, in white, on your layer mask. That's the spermlike image below. I accidentally used a slightly soft brush, so it's already a little ragged.

5)Now, use Gaussian Blur on your sperm mask. Blur it to the desired spread width. I used a fairly large 27.5-pixel blur for this one. I have an image of the blurred mask below as well as the final spread image that results from using that mask as a dissolve.

6a)Once you have this method down, you can record it as an Action. I'll name mine, "Spread." I'll use that term in future tutorials to refer to this method for simplicity.

optional step)For additional interest, you can copy the mask into the image part of the dissolve layer. This can be useful for some methods I might describe later. If you like, you can save this as a, "Blurred Spread," action. Again, I'll be using, "Blurred Spread," as a shorthand in future tutorials. Assuming I don't forget.

note)I still haven't saved these as Actions. Me mal...

02-08-2008, 02:36 PM
It looks like Filter>Brush Strokes>Spatter... with the minimum smoothness of '1' will do pretty much the same thing.

Okay, now that you have an image, spread by whatever means. Here's a little bonus thing you can do.

1)Use Gaussian blur on a really small radius. I used 1.1 pixels below.

2)Use that lovely spatter filter with a moderate Spray Radius and Smoothness, I used 12 and 8 below.

This makes the effect more clumpy. In the future, I'll show you how this, "Clumping," method can be useful.

Thank you for your attention. Hopefully, this will prove useful to you.

02-08-2008, 04:47 PM
Thsi si great, Colin! Thank you so, so much! I can see many, many uses for this technique (and thanks too for reminding me about Actions--I always forget about those and so end up doing the same danged things over and over again!

...This is the first in a series of short essays on methods I have found to work around some of these seeming deficiencies in PS...

Be still my heart!! Seriously? First in a series?? Oh man--that makes my day!!

02-12-2008, 09:15 AM
Here's a PS brush that can do that in one shot:

Tweak the settings as needed to get the shape control you want. Currently I have flow and size hooked to pen pressure.

02-12-2008, 11:43 AM
Yeah, as it turns out I probably came out with the hardest way to do it. Thanks for the brush, mate. The spatter filter(with smoothing 1) would still be the way to go for text or existing shapes.