This ones a mix of black and white Daler Rowney watercolour paints which I got from Poundland ( £1 for the pair ) I added a little of the white to the black and thinned it with water and a good slosh of flow improver , all mixed in an empty bottle . Ive used the UMP washes in the past but found they can be a bit hard to get right - either wiping straight out of the panel lines or sometimes staining the paint and not coming off . The watercolours are very forgiving , if you cock it up you can just wipe it clean and start again , no staining . I let it dry overnight then start rubbing with a dry cotton bud , only dampening it if the wash doesnt come off first time.
The other one I use sometimes is Modellers oil wash , from John in the
Scale Model Shop , very nice to use and cleans up easily with a bit of odourless thinners .
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