Spray Finishes

A good teaching video on spraying finishing varnish on artwork. It's by Golden but should work for any spray finish.
It seems spraying scratchboard is the bane of any artist, even with some jokingly saying to do it while taking Valium. There seem to be many opinions on which sprays are the best, but standard advice is:
spray on warm, dry days
spray in a dust free area
don't mix brands or types of spray - it can cause cloudiness and even cracking
Edited:  I just bought and used Lascaux UV Protect Semi-Matte finish and I will keep buying it for now. It sprayed well, gives just a very soft sheen to the artwork, deepened the blacks nicely, and didn't show dust much at all. It is quite expensive compared to most other brands and it really has a strong toxic smell - use a respirator!
Edited again: I finally got a great finish on one - I put the board at the 45 degree angle recommended then sprayed with 5 very light coats with about 15 minutes between each. No orange peel, no dust spots, no gloppy stuff.

Scratch Bags

 I took a break one day to make some small bags to put scratchboards in. I kept just setting the finished work on a table in my studio and, while it was fun to see it out, it was also putting them at high risk for damage. I need to get some framed but haven't done it yet.
So these bags are made from grey felt and fancied up with quilting cotton I already had on hand. The ones in the top picture are all 5x7 and the ones in the bottom picture are around 10 - 12 inches. I like the grey ones to slide into a larger bag. The ones totally covered in cotton are a little more protection with the extra layer of fabric.
These are just a simple foldover bag - no hardware or buttons. The top piece folds completely over the bag giving one more layer of fabric over the scratchboard if you put it in the way the top photo shows.
I may put a few of these on Etsy. Anyone out there interested?

Just Playing Process

 In the original photo the girls were playing with face paint for the first time. I started with the intention of adding it, but once I got into the details of the faces I liked it too much without the paint.
The paint did make it much more difficult to see the shadows and details in some areas of their faces.
For the start of it I just very loosely added Ampersand black ink with a brush, let it dry, then started scratching out details bit by bit. This was after enlarging the photo to full size and tracing it onto the Claybord. I don't try to draw images onto the boards any more. I know how to draw, but would rather spend my time doing the scratching.
In this last one I was reinking to make the cheek shadows darker and being frustrated by the blotchy texture after I had it so smooth. I almost went to buy an airbrush, but decided to give it one more try. Using the scalpel and a VERY light touch I was able to smooth the skin, keep the darks, and not buy the airbrush. I used very soft short lines and stippling.

Scanning and Processing Black Scratchboard

The mottling in the first and second images is from the matte varnish that is sprayed on.
Adjusting the blacks helps remove most of that and  careful dust removal using the cloning tool can take out the rest.

Getting a good scanned image can take a lot of practice and experimentation. I'm still learning, but this is what I'm doing so far especially in achieving the rich blacks of scratchboard.
When I scan I use an Epson Perfection 600 scanner which will do prints and also negatives and transparencies. I always hit the reset button to take off any scanner adjustments to sharpness, color, or levels and do those myself later using a photo editing program (Photoshop Elements 11 which came with the scanner).

When I open the raw scanned image in Photoshop I first adjust the levels with the original artwork right beside me to compare. I try to get the blacks as dark as I can without losing any of the lighter values in the image. I do the same to the white levels - get them white without losing any of the subtle grey values near them. If it is a black and white image I also strip out the colors using the desaturate feature.

Then I start going over the blacks especially doing dust removal with the cloning tool. It takes a fair amount of time to do this right. I zoom in quite a bit on the image to be sure to get it all. I get a bit obsessive in this stage to get as much as I can. At this stage I could also remove any smudges in the dark areas and also transfer lines that still may be there.

Once I have the image the way I want it I may sharpen it a bit - but not too much or the subtle areas will be lost. I also add a layer and tint it to 5-7% transparency with an olive color to bring back the warmer tones in of the scratchboard.

If I want to print the image I usually have to run a few test prints and make a few more adjustments to get the print matching the artwork - again with the original artwork right beside me.
That is my process at this time. It works pretty well for me so far. I got a lot of tips from the wetcanvas scratchboard  forum, and especially Cathy Sheeter who is one of the moderators for the forum.