fumed silica

[jp]

Anyone else pre-coating with it? I tried some I got on ebay or amazon, brushed it on dry and found it made the paper (arches platine) quite repellent:

https://plus.google.com/u/0/photos/110213069218089191660/albums/6105867633971856305/6105867634227897650?pid=6105867634227897650&oid=110213069218089191660

I suppose buying the stuff B&S sells would be easiest but that takes the mad scientist fun part out of it. If other people are have good results, I may add that to the order next I order with B&S.

[Andrew O'Neill]

I tried… and I tried… and after several sheets of paper and sensitizer, I gave up. Yes, there was a dramatic increase in dmax, but it was hit and miss as far as streaking went. I much prefer acidifying paper in sulfamic acid. Now I have a ton of fumed silica in my darkroom. Maybe I'll make some milkshakes with it...

[Jim C.]

I assume you're pre coating photographic paper with fumed silica ? What's the coating for ?
Just curious because I use it a lot as a thickener for silicones and urethane rubbers and as a matting agent for some paints.

[jp]

It's been used by some to increase blacks for alt process printing (probably by increasing surface area for coating). It's foam brushed onto dry Arches Platine paper in my case.
https://www.bostick-sullivan.com/cart/product.php?productid=1254&cat=0&page=1

[John Bowen]

See Richard Boutwell's Blog post, dated March 2012. May shed some light
http://www.richardboutwell.com/blog/