An excerpt from Jill Enfield’s book Photo-Imaging (unfortunately out of print!) complete with how-to and formulas on how to size papers.
Sizing paper is a matter of choice. Some sources say that you must size before printing, others recommend it for some papers and fabrics only. Different sizings can affect not only the color of a final print but how smooth or sharp the image looks as well. I recommend it on everything but paper for most processes, however, for paper uses, I only size paper when I am gum printing or combination printing (using 2 processes together).
I have listed below many different types of subbing and sizing solutions. There are others that are specifically for Liquid Emulsions. Before making a final decision, try a print with and another one without sizing.
When using fabrics or canvas, always wash out the manufacturer’s sizing by soaking the paper in hot water before printing or you will get uneven absorption and cause problems with your alignment of the negatives as you put one exposure on top of the other.
Preparing and cleaning glass before subbing and printing
- Using powdered laundry or dishwasher detergent make a strong solution in hot water.
- Scrub the glass and rinse until the solution does not bead up on the glass any longer.
- Now it is ready to be subbed.
I use Bon Ami – a non- abrasive cleanser.
If you don’t have running water you can use All Purpose Whiting. Mix up a solution and store in a container that you can take with you. Use it as a buffer on glass in the field.
For Polaroid Transfers
For more intense colors and blacks:
- 1 envelope of Knox unflavored gelatin to 2 cups of distilled boiling water. Mix well.
- Add Kodak Photo-flo, about 3 drops
- All to cool to 1000 – 1300F before use.
- Place in a tray slightly larger than your paper
- Put you paper in the solution for 1 minute
- Remove the paper and place face down onto the flat surface you are using.
- Squeegee until moist and uniform. DO NOT ALLOW TO DRY.
The gelatin gets thicker as it cools. Try to keep it warm while using and only use 1 piece of paper at a time as needed.
You can use: Gloss Polyurethane spray as a sizing:
- Several light coats on metal, ceramic, plexi or glass.
- Do not use the matte or semigloss because of the wax in their formulas.
#1. Gelatin sizing with hardner (1 step)
From the Silver Gelatin book by Martin Reed & Sarah Jones:
Make a 2% Chrome alum solution:
- Hot distilled Water 500 ml
- Chrome Alum 10 grams
Mix until well dissolved
Then in another container:
- Hot distilled water: 750ml
- Gelatin: 7 grams
- 2% Chrome alum solution: 20ml
- Distilled water to make: 1 liter (total)
You can re-warm for a few days and then you will notice a strong smell.
#2. Arrowroot starch
Photographer’s Formulary usually includes a package of arrowroot starch as their sizing method: (this has a slight unpleasant odor as you make the mixture). Use within 24 hours!
- Place the starch in a 1-liter pan so that you can heat it up safely.
- Add about 20 ml of hot water stirring until the mixture is a thick cream. Be sure that no lumps remain.
- Add 1 liter of hot water with constant stirring.
- Boil the mixture for 5 minutes, then let it cool to room temperature.
- Skim off any scum so that you can. Pour only the clear solution into a storage container.
To apply this to paper or fabric:
- Brush the solution onto the support, first horizontally, then vertically until the paper is wet.
- Take a clean, dry brush and work the surface until it loses its gloss.
- Allow the support to dry before applying a chemical to it.
#3. Knox Gelatin: bought in grocery stores:
For liquid emulsion:
- Put 7 grams (1 package) of unflavored food gelatin in a pot
- Add 1 cup (250cc) of cool water
- Let it stand for 15 minutes so that the gelatin can swell
- Stirring constantly, heat the mixture until the gelatin is dissolved (1400 to 1600F)
- Cool the solution until lukewarm then pour over cleaned glass
- you can re-warm for a few days and then you will notice a strong smell.
Gelatin sizing with hardening: (2 step process)
GELATIN: Mix as stated above
HARDNER:
You can use chrome alum, glyoxal, or formalin (formaldehyde). These are listed in order of toxicity.
- After the paper or other surface has been coated with gelatin and dried, coat the surface with the hardener.
- REPEAT 3 TIMES!!!! Coating first with gelatin, then with hardner, drying in between.
Mixing instructions for the hardner:
Chrome Alum
As stated above (but do not mix in with gelatin – keep separate!)
Formalin
37% solution of formaldehyde is diluted with water and 15% methyl alcohol is used as an antiseptic, disenfectant, preserver of specimens. This keeps forever.
Add 25ml of formalin to 1,000ml of distilled water which makes a 3% formalin hardening solution.
Glyoxal
- 15ml of prepared 40% glyoxal solution to every 1,000 ml of distilled water.
- add 1/2 teaspoon of baking soda per liter of solution.
This only keeps for a few days.
Do this step outside or with a mask on.

Photo Imaging – A Complete Visual Guide to Alternative Techniques and Processes
A definite resource for mastering alternative photo-imaging techniques. Out of print.
For those unfamiliar with the Fahrenheit scale and our body temperatures or the boiling point of water, the temperature range listed in the sizing-or-subbing article is off by a factor of ten, I would suggest. I’m using other materials, so have not checked this. Double check the preferred range with other sources, and I think you’ll find that dividing the temps given by ten would help.
Yes, second the temperature is over the top!
For #3, 1400 degrees seems a little hot dontcha think.