Gum Bichromate Print Question - Is this Solarisation?

[ehsankiani]

Hello.
I have just started with gum bichromate printing a month ago and learning my way. Wanted to ask about the issue in this image. I printed a negative on paper and waxed it to make prints. I used a 1:1 gum / potassium bichromate solution with added black poster colour. Different papers. Is the effect on the right side of the face due to Solarisation. I used a 4.5 minute exposure here. Posting the negative along with it too. Previous print did not have this effect.
Thank you for your feedback.

 

[ehsankiani]

Here is the previous print from the same negative. Same chemistry only that the brand of gum arabic and the paper was different.

 

[Andrew O'Neill]

I can only see what appears to be brushing issues... Are you smoothing it out with a hake brush?

 

[koraks]

Looks like part of the mid tones lifted off the paper. I'm no gum expert, but I understand that paper surface and sizing play a significant role here. Calvin Grier refers to "surface energy", but that turns out to be a rather involved and expansive topic. Basically it's about how well an emulsion will stick to a paper, and several factors influence this.

 

[Andrew O'Neill]

What koraks said. And... It's always best to strive for an even, thin coating.

 

[Herzeleid]

Use less pigment. Try to determine the ideal pigment load for particular amount of gum arabic. Ideal load will be different for each type of pigment.

Thayer Gum Tonal Inversion

 

[Dwayne Martin]

So many things can go wrong with gum. Could it be the wash is taking off too much pigment? I have had results similar to that when my washing was too aggressive. In my case now I let most of the development happen in the trays then I give it the most gentle wash passible to take the last bit of loose pigment off. If i don't do that then I get excessive pigment stains that are basically runs as it hangs to dry. All that said Ive seen plenty of videos where people basically spray the print with a hose and it seems to work out fine for them.

In my darkroom if my exposure time s in the ball park I can get a print developed in two trays in 30 minutes or so.

 

[ehsankiani]

Thank you so so much for all the replies. All of you are actually right. I learnt that I was washing too aggressively, pigment was a bit too much for that batch and I was washing with hot water. I am now using normal temperature water and gentle agitation. Does great.
As I said, this is just my first month into this technique and learning my way through. I am glad I stumbled across this forum. Long way to go for me so expect more queries and questions from the other side of the globe
Ehsan