Alternative process
AdvancedAquaprint
The precision of photography, the luminosity of watercolour
Aquaprint — our name for gum print — uses a pre-sensitized VP gum into which you incorporate your powder pigments. After sizing with transparent gesso, application by brush and foam roller, Luminograph exposure, the N°06 developer followed by hot water clearing reveals your image. Three variants: Color (CMYK four-colour), Sanguine (raw sienna) and Monochrome (deep black).
The pictorialist heritage
This process allows the artist to physically intervene on the image during development. Using powder pigments, one creates images that are as much drawings as photographs. Early 20th-century pictorialists made it their technique of choice. The VP kit eliminates all the complex chemistry of the old process: the gum is already pre-sensitized.
Materials
640 gsm watercolour paper · Transparent gesso · VP Gum (pre-sensitized) · VP Developer N°06 · Powder pigments · Foam roller
Three variants
100% non-toxic
All our chemistry is reformulated by Vision Picturale to be safe for home use. No toxic products whatsoever.
In 4 steps
Make an Aquaprint in 4 steps
Prepare
Scald the 640 gsm sheet, then apply 4 coats of transparent gesso (sizing).
Calibrate
Melt the VP gum in a bain-marie, mix in your powder pigment, apply by brush then roll with a foam roller.
Expose
Expose with the Luminograph (2 to 5 min depending on pigment — negative).
Reveal
Develop 10 s in diluted N°06 bath, then clear in hot water (40°C) — the image appears before your eyes.
Historic bridge
Aquaprint vs historic gum bichromate: what we changed
Gum bichromate — also called gum print or gumprint — has been the pictorialist process par excellence since 1894. But its original formula relies on potassium or ammonium bichromate: a chromium VI salt classified as a proven carcinogen (CMR 1A), banned for non-professional use in France since 2018. Impossible to practice in a kitchen.
Aquaprint preserves the entire visual grammar of gum bichromate: brush application, layered passes, physical intervention with a roller, hot water clearing that reveals the image. The gesture is identical. The rendering — translucent pigment layers on cotton paper — is indistinguishable from the original to the naked eye.
What we changed: the sensitization chemistry. VP gum is pre-sensitized with a non-chromium system we developed over three years. No bichromate, no chromium salt handling, no mandatory PPE. The N°06 developer replaces the bichromic acid baths of the historic process.
Concrete consequence: a beginner can start an Aquaprint on the kitchen table, without gloves, without a mask, with children in the room. That is exactly what pictorialists' gum bichromate did not allow — and it is what finally makes this process transmissible.
Frequently asked questions
Everything about this process
What is Aquaprint?
Aquaprint is the non-toxic reformulated version of gum bichromate, a pictorialist process developed in the early 20th century by Robert Demachy and Constant Puyo, then members of the Photo-Club de Paris. Historic gum bichromate sensitized a mixture of gum arabic and pigment with potassium dichromate, a salt classified as carcinogenic and mutagenic under the European CLP regulation. Aquaprint Vision Picturale completely removes the dichromate in favor of VP N°03 Universal Sensitizer, combined with pre-sensitized VP N°04 gum arabic and powder pigments. Development uses diluted VP N°06 developer and clearing in warm water at 40°C. Three variants are available: CMYK four-color in four successive layers, single-pigment Sanguine in Sienna earth, and monochrome carbon black in one to two layers.
Why is Aquaprint non-toxic without dichromate?
Aquaprint Vision Picturale is entirely free of potassium dichromate and ammonium dichromate, the two salts traditionally used in gum printing since 1858 and classified as CMR category 1B by the European Chemicals Agency (ECHA). Sensitization relies on VP N°03 Universal Sensitizer, whose safety data sheet lists no carcinogenic or mutagenic pictograms. Pigments supplied are mineral earths and oxides rated ASTM I lightfast. The VP N°06 developer used in the final bath is non-volatile and biodegradable. The practitioner can concretely prepare layers on a kitchen table, clear in a plastic tray with warm tap water, and dispose of wastewater through standard drains. Nitrile gloves remain recommended when handling powder pigments during initial mixing with VP N°04 gum arabic.
What are the steps of CMYK Aquaprint?
A four-color Aquaprint Vision Picturale print comprises four successive CMYK layers. The practitioner mixes VP N°04 gum arabic pre-sensitized with VP N°03 Universal Sensitizer together with the powder pigment for the relevant layer, applies it with a flat brush onto 640 gsm 100% cotton watercolor paper, and lets it dry thirty minutes in darkness. Exposure under a 365 nm Luminograph A4 unit lasts two to five minutes depending on separation negative density. Development immerses the print in diluted VP N°06 developer, followed by clearing in warm water at 40°C for five to ten minutes: unexposed gum dissolves, hardened pigment remains. After two hours of drying, the next layer is applied. A complete four-layer A4 print requires roughly eight to ten hours spread over two days.
How does Aquaprint differ from Gumoil?
Aquaprint Vision Picturale differs from Gumoil through its use of powder pigments dispersed in VP N°04 gum arabic pre-sensitized with VP N°03, revealed by clearing in warm water at 40°C which dissolves unexposed gum. Gumoil uses the same VP N°04 gum and the same VP N°03 sensitizer, but incorporates ground oil pigments fixed by selective adhesion without aqueous clearing. Aquaprint enables CMYK four-color printing, therefore color images faithful to the negative, which Gumoil does not allow in practice. The practitioner will choose Aquaprint for complex color images or nuanced graphic monochromes, and reserve Gumoil for contrasted graphic subjects where the raw pigment matter prevails over tonal fidelity.
What skill level does Aquaprint require?
Aquaprint Vision Picturale is practiced at two levels depending on the variant. The monochrome carbon black variant in one to two layers of VP N°04 gum sensitized with VP N°03 is accessible from advanced-beginner level, ideally after five to ten successful cyanotype prints. The single-pigment Sanguine variant in Sienna earth follows the same logic, with the warm rendering characteristic of Demachy prints from 1900. The CMYK four-color variant requires confirmed intermediate level: precise registration of the four separation negatives, constant pigment-gum dosing between layers, and exposure time control to within ten seconds. The VP Aquaprint kit remains to this day the only non-toxic four-color gum print kit on the market.
How permanent is an Aquaprint print?
An Aquaprint Vision Picturale print kept in standard conditions resists for several centuries, a permanence comparable to the historic Demachy gum bichromates still visible at the Musée d'Orsay and the Metropolitan Museum of Art in New York. This longevity stems from the mineral pigments used, earths and metallic oxides rated ASTM I lightfast in Winsor & Newton or Sennelier catalogues, and from the inertia of VP N°04 gum arabic once hardened by VP N°03 Universal Sensitizer. The practitioner must nonetheless choose only pigments with maximum light stability rating, avoiding organic lakes and certain aniline reds. The final print supports standard framing behind anti-reflective glass, in an environment with humidity below 60%.
Complete kit
Aquaprint
Aquaprint — our name for gum print — uses a pre-sensitized VP gum into which you incorporate your powder pigments. After sizing with transparent gesso, application by brush and foam roller, Luminograph exposure, the N°06 developer followed by hot water clearing reveals your image. Three variants: Color (CMYK four-colour), Sanguine (raw sienna) and Monochrome (deep black).
An alternative
Want an Aquaprint artwork, not make it yourself?
The artisans of Maison Picturale produce Aquaprint prints on commission — colour (CMYK), sanguine or monochrome — in their Paris atelier. Minimum three passes, 640 gsm cotton paper. Vision Picturale supplies the kit to practice at home; Maison Picturale supplies the finished, signed artwork.
Order an AquaprintMaison Picturale · Paris 20e
