Different appearance of brushes when used in different pictures.

[eliza89681725]

When I create a new brush using the Mixer Brush Tool, the colours are faithful, as long as I use that brush in the same image from which it was created. When I use the new brush in any other image, the colours become muddy. Attached is a screenshot of PS with three partial images (to make uploading quicker) vertically arranged. The original, on the right, from which I created the brush, shows the new brush stamped right beside it, displaying the same colours. Using that brush, in the two images on the left produces dead-looking colours.

All three are RGB, 8 bits. I made no changes in Brush Settings and I have restarted Photoshop. Can someone please explain how to fix this.

[Kevin Stohlmeyer]

@eliza89681725 Am I looking at this correctly that your brush is the Monarch wing itself? Depending on your settings in the options bar for the Mixer Brush, your load rate or wetness settings could be causing this and mixing to give you the muted results. The purpose of the Mixer Brush is to blend colors together simulating wet or dry media. It's not meant to give you exact copies like a standard brush. 

[D Fosse]

Brushes just go by numbers, which will produce different colors depending on color space. This is pretty much consistent with sRGB <> ProPhoto.

What color space was the brush created in, and what color space is the brush used in?

[c.pfaffenbichler]

Along @D Fosse ’s post please set the Status Bar to »Document Profile« and post screenshots with the pertinent Panels (Toolbar, Layers, Options Bar, …) visible? 

[eliza89681725]

Thank you all for your replies. All images were created in the same colour space. Load/wetness were the same. However, I cannot duplicate the problem today (project scrapped), but I will attempt to do so later.
Re: It's not meant to give you exact copies like a standard brush. 
I don’t understand as I have long used the Mixer Brush Tool to create Tool Presets to make brushes for exactly that. Perhaps I am using the wrong terminology. More confused.
Sample of brush created with Mixer Brush, attached.

[Anshul_Saini]

Hi @eliza89681725! Thanks for the update.  Yes, please do let us know if this happens again. If possible, try to make a quick screen recording when it does, that’ll help us & experts on this post understand the exact steps and settings being used so we can narrow down whether this is expected behavior or a potential bug. It’ll make it easier to troubleshoot.

Looking forward to your next update!

Best,
Anshul Saini