Can't get the Colour Replacement Brush tool to work

[BatteriesInc]

I have a simple JPG generated by some software, and I'd like to replace one colour (straight black or white) with another, or make it transparent.  So far, any attempt to use the colour replacement brush tool have not given any result, and my search on the forum found its use to be an as yet unanswered question.

 

I was hoping this brush would act as pick-and-replace tool (if pixel is <colour set> then replace with the colour set as front) but evidently I have this wrong.

 

As I have both AD and AP, here are my questions:

 

- which is the best to use?

- what is the exact process to replace a specific colour x with a colour y? (layer select, any settings that can mess it up, which brush to choose, how to choose the colour to change and set the colour it will be replaced with).

- just in case I come across this later, is there also a way I can control the *range* of colours accepted for replacement (the cat example isn't universally the same orange).

 

I'm clearly missing something simple, but I can't seem to identify what.

[Lee D]

Hi BatteriesInc,

 

Using the Colour Replacement Brush Tool in Affinity Photo, you first need to select the colour you wish to change to on the Colour Panel. I'd stick with one of the Basic brushes, you'll have options to adjust on the Context Toolbar like Width, Opacity etc, you can also adjust the Tolerance level. Remember this process will replace the targeted colours hue with the replacement colours hue while retaining lightness.

[BatteriesInc]

Thanks Lee, I literally just discovered a different route to Rome - as I needed the background transparent, the power of the erase tool came to the rescue instead.

 

However, I will preserve your answer (or rather mark it) because I do indeed want this to work :).

 

Thank you for helping!

 

Cheers.

[R C-R]

Remember this process will replace the targeted colours hue with the replacement colours hue while retaining lightness.

I mentioned this once before but since this is what it does, for clarity why isn't it called the Hue Replacement Brush???

[pixel-girl]

Yesterday I played a little bit with AP and has a "Close Encounters of the Third Kind" with the Colour Replacement Brush! :blink: :blink: :blink: :blink: ... :lol:

It was mysterious! It was perhaps a little creepy, but it was definitely neither intuitive nor WYSIWYG!

 

.......

 

After this "epic encounter" I find here the answers and, among other reasons, this topic.

A screen-shot "replacement-cause.jpg" is not more necessary, but what in the future can I do with such a tool?

 

When I cannot see what I do, I can only play and for example try to recolour the eyes of my cat on all pictures and hope ... ( whatever...) But I cannot work with it.

 

@ R C-R: Let's call it "Hue Replacement Brush", but  for what purpose we have this tool?

[R C-R]

@ R C-R: Let's call it "Hue Replacement Brush", but  for what purpose we have this tool?

So far, the only use I have found for it is, ironically enough, to remove the color (hue!!!) from some scans I made of an antique wall plaque in areas that I wanted to be greyscale, like where in the original scan black text had a lot of color noise. To do that, I set the foreground color to pure white, ramped up the tolerance to very high levels, & enabled "Sample continuously."

 

But there was nothing intuitive about it. The Color Replacement Brush Tool Affinity Photo help topic is not very helpful in this respect. The explanation for the brush's effect is:

The pixels affected by the Color Replacement Brush are determined by the following:

• The color of the pixel under the tool when you click on your page.

• Whether the pixels are within the same selection area.

• The pixels are included in the painted stroke.

• The tool's Tolerance settings (see below).

 

Not very clear, at least to me. For instance, what is the difference between the selection area & the painted stroke?

 

And of course, it says "The Color Replacement Brush Tool works by replacing the color of pixels on the current layer with the Foreground color selected on the Color panel" but in fact it only replaces the hue value.

[pixel-girl]

So far, the only use I have found for it is, ironically enough, to remove the color (hue!!!) from some scans

 

Exactly my kind of humour.

 

Affinity Photo help topic is not very helpful in this respect. The explanation for the brush's effect is:

[ ... ]

Not very clear, at least to me. For instance, what is the difference between the selection area & the painted stroke?

 

And of course, it says "The Color Replacement Brush Tool works by replacing the color of pixels on the current layer with the Foreground color selected on the Color panel" but in fact it only replaces the hue value.

 

 

One thing I can say: The German translation of AP help topics is, incl. error in reasoning, perfect!

In German version we have an "of course"² because it says:

"The Color Replacement Brush Tool works by replacing the color ..."

(Yes. It's really bold!)

 

:D

 

I cannot believe that's a feature. It must be a bug!

[R C-R]

I believe it is "by design" rather than a bug. In my old topic I asked about a video tutorial demonstrating how it works & Leigh was kind enough to post a link to a movie showing that. MEB also referred to it in a recent post as "a Colour (hue) Replacement Brush Tool" so the name aside it seems to be working as intended.

 

The way I (now) understand it, it works this way so it can be used to change the hue while leaving the texture untouched, like in the video.

 

Regardless, while that will be useful for some things I would love to see a new tool or a different mode for this one that replaced color instead of just hue values so it also removed the texture, with similar tolerance & other options. I have quite a few old scans, video captures, & other files that have a lot of color noise that I would like to remove, in part to make them much more compressible & thus smaller when exported to formats that support pixel compression. The Median Brush Tool is the closest thing I have found for doing that but it still does not completely remove the noise like a true color replacement brush would do.

[JodiSte]

For me this colour replacement brush is not working at all.

I do as described, select a colour first (white)

Then select the colour replacement brush

Then move over a black area, nothing.

If I move over an orange area the tool turn grey and when clicking makes the orange area grey.

 

I have not selected grey and I need the black area to turn white.

 

This is not user friendly behaviour of an app.

 

What do I do wrong?

 

Please provide videos! We live in the 21st century, please

[R C-R]

Hi JodiSte & welcome to the forums.

 

As I mentioned above Leigh provided a video showing the colour replacement brush in use. It does not replace color, just hue.

 

To replace the color, use a regular brush set to the desired color, if needed along with the selection brush or one of the other selection tools to confine the change to a selected area.

[toltec]

I rather like the colour replacement brush but if the "colour" you want to change lacks "colour" it is useless. i.e. black, white or grey.

[BSAS]

On 5/31/2017 at 10:16 AM, toltec said:

I rather like the colour replacement brush but if the "colour" you want to change lacks "colour" it is useless. i.e. black, white or grey.

 

So this is wasted an hour or two trying to do a simple task! Should have just used Photoshop - really going off Affinity!!

[4CardsMan]

How do you select the color that you want to replace?  (the target color?)  I have viewed three tutorials and none of them show you how.

[MM95]

In-fact, I don't really know what the colour replacement is doing. But its not replacing colour thats for sure!

I have a colour, lets say a simple blue. I want this to be red. So my intuition is to use the colour picker to pickup the colour I want to replace (Blue), then switch to foreground and select the colour red from the picker. I then select colour replacement tool, tap the blue areas that need to be red and it just draws red over the blue, but if I go outside the blue and go over green or a transparent background, it continues drawing red. - This is not a colour replacement.

In a more demanding exercise, I have something that is gradient blue that I want white. Colour fill to white does 90% of whats needed, but it leaves coloured dots around the outline of my shape. If I was using Photoshop or Paint Shop Pro, I would just colour pick the gradients then use the colour replacement tool with a white and brush over my image, only the colour that I colour picked changes to white. I then repeat the process with the other dots of gradient I have.

Can we see this feature being improved? This isn't a new tool, I was using this back in the day when JASC made Paint Shop Pro v7 (back in 1990 I believe!) I have invested in Affinity Photo and would like to see this tool do what it should.

 

[walt.farrell]

1 hour ago, MM95 said:

In-fact, I don't really know what the colour replacement is doing. But its not replacing colour thats for sure!

It is replacing Hue, while keeping Saturation and Lightness the same, as described in the Help.

https://affinity.help/photo/en-US.lproj/pages/Painting/replaceClrs.html

[Komatös]

@MM95

Use the HSL adjustemnt layer to replace. 

[FoxyCornelieus]

I believe the tool would have to work the way that it does (adjusting hue only) in order for it to be useful for recoloring a photo. But I also feel the help files are not very clear about this point and that @R C-R's solution about fully replacing the color using a regular brush and the Flood Selection Tool to replace the full color with an exactly matching color should be mentioned in the Help. It also should be mentioned that it is not required to first select the color to replace (i.e. it is based on your first click).

In short, good tool, could be better explained.