Collotype vs Photogravure
コロタイプ / フォトグラヴュール
Collotype comes from Planographic Printing and Photogravure from Intaglio Printing. They are reached for with some of the same intent, which is where they get confused.
Collotype
A photomechanical process that prints ink from a photographically prepared gelatin surface. Fine, irregular reticulation carries detail and smooth-looking tones rather than a regular halftone screen. It has reproduced photographs and artworks; it is unrelated to the collaged matrix of a collagraph.
Photogravure
A photomechanical intaglio method that transfers a photographic image to a plate and prints it in ink. Fine detail and apparently continuous tones acquire the character of paper and ink. It is distinct from a silver photograph, planographic collotype and the industrial context of rotary gravure.
| Collotype | Photogravure | |
|---|---|---|
| Era | 19th century–present | 19th century–present |
| Family | Planographic Printing | Intaglio Printing |
| Kind | Technique | Technique |
| Cues | Detailed images derived from photographs or originals / Apparently continuous tonal changes / Fine irregular reticulation under magnification / Tone without a regular dot screen | Photographically derived detail / Rich printing-ink blacks / Fine grain carrying tonal changes / Plate image in relation to paper |
| Best used for | Exhibitions and teaching that compare Collotype with neighbouring print techniques · Publications studying lines, tones and paper through documented works | Exhibitions and teaching that compare Photogravure with neighbouring print techniques · Publications studying lines, tones and paper through documented works |
| Type | Keep lettering in the work separate from added labels; place medium, artist and date outside the image. | Keep lettering in the work separate from added labels; place medium, artist and date outside the image. |
| Composition | Pair details with the whole image and distinguish the microscopic pattern from overall tone. | Compare blacks, midtones and highlights so that dark areas retain useful detail. |
| Material | Check the collection medium record and the paper and ink; do not infer materials from screen colour alone. | Check the collection medium record and the paper and ink; do not infer materials from screen colour alone. |
| Caution | A screen image may conceal the diagnostic pattern. Use the collection's medium record, and distinguish collotype from collagraph. | A sepia palette or plate border alone proves nothing. Check the recorded printing process and distinguish later reproductions. |