2021 Live Demo Pt/Pd 1.11.21

Bostick & Sullivan Darkroom Night

Platinum & Palladium Printing Demo & Discussion

Sponsored by Hahnemuhle


watch here: https://youtu.be/Mlg0CL0704g

and here: https://www.facebook.com/BostickSullivan/videos/405225274071113



Supply list:

Pictorico Premium Inkjet Media

Bostick & Sullivan Platinum & Palladium Kit for Digital Negatives

Tween-20 10% Solution

Synthetic Sable Brush

Puddle Pusher Glass Coating Rod*

Hahnemuhle Platinum Rag Paper

Disposable Salsa Cups or Shot Glass For Mixing Emulsion

Distilled Water For Wetting Brush



Equipment list:

Bostick & Sullivan Contact Printing Frame

Edwards Engineering UV Light Box

Nuarc 26-1KS Vacuum Frame & Plate Burner*

Paterson Developing Trays


Negative Preparation:

6x9 inch (15x23 cm) image @360 dpi resolution minimum

Pictorico Premium Inkjet Media 8.5 x 11 inch

Epson P-800 printer with Epson Ultrachrome HD inks

Adobe Photoshop

Bostick & Sullivan correction curve


Our negatives were created using a high quality digital file and printed using an Epson P-800 printer. The image was edited in Photoshop and then resized to fit the output media. A correction curve was applied to calibrate the negative’s density and contrast to match the sensitivity of the Platinum/Palladium emulsion.


Bostick & Sullivan PDF and Video tutorials for making inkjet negatives are available at:


Coating Paper:

We are coating Hahnemuhle Platinum Rag 11x15 inch paper with a 2 inch Langnickel synthetic sable hair brush. We mark the paper with a pencil to act as a guide for spreading and concentrating the emulsion in the image area.


Drops Chemical

14 Ferric Oxalate #1

11 Palladium #3

4 Sodium Platinum Na2 5%

1 Tween-20 10%


Spread the emulsion on the paper using the tip of the brush. Using a wet brush will keep the expensive emulsion on the paper instead of soaking into the brush. Allow the coated paper to air dry for 30 minutes before exposing.

Exposing The Image:

Place the negative against the coated paper, emulsion to emulsion, and place it in the split-back contact printing frame. Insert the print frame into the Edwards Engineering UV exposure box and expose for 6-8 minutes.


We are using a saturated solution of Potassium Oxalate as our developer. 


Potassium Oxalate produces a subtle warm tone Platinum/Palladium print. The developer is undiluted, and does not become exhausted from continued use. Development is almost instantaneous, but we recommend leaving the print in the developer for 2 minutes to allow it to penetrate the fibers of the paper completely.

Clearing Bath:

Once developed, the image is permanent and needs no fixer. However, a clearing bath to remove the yellow stain left in the image highlights is needed. We use a mild solution of Sodium metabisulfite and EDTA to dissolve the stain, and change this solution when it becomes red from dissolved iron. Two successive clearing baths may be needed for some papers.


To make a clearing bath mix:


30 grams EDTA Tetra Sodium

30 grams Sodium Metabisulfite

1 liter tap water


Drain excess developer from the print. Next, soak print in the clearing bath solution for 6 to 8 minutes. Agitate clearing bath once per minute.  After this time, the yellow stain should be removed from the paper completely.

Archival wash and drying:

After the clearing bath, wash the print for a minimum of 30 minutes with a constant stream of cold water.


After washing, set the prints on screens to dry. Flatten dried prints in a dry mount press set to 225F for 2 minutes. Mount on archival matt board.