Kallitype

Kallitype

Kallitype is a process for making photographic prints.

Patented in 1889 by W. W. J. Nicol, the Kallitype print is an iron-silver process. A chemical process similar to the Van dyke brown based on the use of a combination of ferric and silver salts. Many developing solutions can be used to give a different image color (brown, sepia, blue, maroon and black). Kallitype images generally have a richer tonal range than the cyanotype. These prints were popular in the 19th century, and then their popularity faded away. Sometimes known as "the poor man's platinum print", when the image is toned in platinum or palladium the result is nearly chemically identical to a true Platinotype. It is believed that many Kallitypes were passed off as true Platinotypes and remain in collections as so. Kallitypes have had a reputation over the years as having poor archival qualities and often fading. When properly cleared, Kallitypes are completely archival and will not fade. Toning with a metal such as gold, platinum, or palladium will give extra image permanence. Ferrous ions embedded in the paper as a result of poor clearing is the cause of the lack of belief in image permanence. This can be easily identified by a yellow stain in the highlights.

Chemistry

While there are many possibly solutions for each step of this process, these are the most commonly used solutions. Each of these has been tested and works well. The sensitizer solutions should not be changed much, but there are many choices in developer as well as clearing solutions.

Sensitizer:

(A) Ferric Oxalate (20% solution - 40g / 200ml H20)

(B) Silver Nitrate (20% solution - 40g / 200ml H20)

Developers: "Listed by tone"

1. Warm Black tones - Ammonium Citrate (15% solution - 150g / 1000ml H20)

2. Black tones - Sodium Acetate (10% solution - 100g / 1000ml H20)

3. Sepia tones - Rochelle salt (5% solution - 50g / 1000ml H20)

4. Blue-black tones - Rochelle salt (9% solution - 90g / 1000ml H20) + 24g Borax

5. Ultra-black tones - Sodium Acetate (40% solution - 400g / 1000ml H20)

Clearing Baths: "Listed by strength"

1. Citric Acid (50g) - 1000ml H20

2. Sodium Sulfite (50g) - 1000ml H20

3. EDTA (30g) - 1000ml H20

4. Heico Perma Wash (4oz) + EDTA (30g) - 1000ml H20

5. EDTA (70g) + Sodium Sulfate (70g) - 1000ml H20

6. Potassium Metabisulfate (50g) + Sodium Sulfate (50g) - 1000ml H20

7. Hydrochloric Acid (5% Solution) "Extreme care must be taken when using Hydrochloric Acid"

Fixer:

Sodium Thiosulfate - 100gSodium Carbonate - 20gSodium Sulfate - 4gWater - 2000ml

Toners

Platinum/Palladium Toner - Platinum or Palladium (5ml) + Citric Acid (5g) - 1000ml H20

Gold Toner - Gold Chloride 5% Solution (5ml) + Citric Acid (5g) - 1000ml H20

Hypo Clear

Sodium Sulfite (1% solution - 10g / 1000ml H20)

Coating

A high quality 100% cotton rag paper is recommended for this process, papers that work well for Platinotype generally work well for this process.All coating must be done under safelight conditions. Gloves are recommended as both sensitizing solutions are quite toxic.

1. Mix equal parts A&B in a shot glass or small graduate. This solution does not keep well and should be used immediately. 3ml will coat a 5x7 image. 2. Use a hake brush or glass coating rod (often referred to as a Puddle Pusher) to apply the emulsion, double coating (letting the first coat dry first) is recommended for a greater dmax. If using a brush the strokes must alternate direct in order to prevent streaking.

3. Let fully dry before exposing, being careful that nothing touches the emulsion while drying.

Exposing

This is a contact printing process and therefor one must have a negative of equal size to print from. A negative of a density range around 1.8 is optimal. This negative can either be made from a large format camera, ortho litho enlargement, or digital negative.

1. The negative is put over the coated and dried paper, then sandwiched between a board and glass to ensure a good contact. Alternatively a contact print frame may be used for ease of this.

2. The image is exposed to UV light in the sun or under a UV box. On a bright sunny day the image may only need to be exposed for a few minutes. Under a UV box the exposures often range anywhere from 5 to 25 minutes.

3. A test strip is advised to figure out the final exposure time with ease.

4. When the shadows of the image are clearly visible and the mid tones look washed out, the exposure should be done. This is called the latent image.

Processing

There are two methods to processing Kallitypes, the multi-tray and single-tray. When using multi-tray, each part of processing chemistry is laid out in a line in different trays. With single-tray, one tray is used and the chemistry is poured over the image and then back into the bottle. If this method is used, it is best to have a distilled water rinse between baths.

1. Developer - Any of the developers listed above will work, it comes down to preference. Developer #1 is the most commonly used. The developer must cover the entire image as quickly as possible. If any part of the image is not covered it will have a permanent mark. It is best to take a dry tray, place the latent image in it, then pour the developer over it. Agitate continuously for a minimum of three minutes, and no longer than eight minutes. A longer development helps removal of the ferrous ions that make the image unstable. Longer development risks staining. A large amount of silver will quickly build up in the developer and it is best to decant your developer every 5-10 prints, depending on the quantity of developer and size of prints. The dark sludge that builds up in the developer will stain your prints.

2. Clearing Bath - The clearing bath must be used until all yellowness has been removed from the print. Generally this will happen in 2-4 minutes. Starting at the lowest strength clearing bath listed, if the stain will not go away, the next strongest clearing bath should be used. When a clearing bath becomes foggy, it is time to replace it.

3. Toning (optional) - Toning alters the image color and increases permanence dramatically. Toners are often very expensive and as little as possible should be used per print. For the solutions given above, this chart will tell you how much to use:

15ml per 4x5
20ml per 5x7
45ml per 8x10
85ml per 11x14
175ml per 16x20

The toner should be poured over the print evenly in a flat bottom tray and agitated heavily until you are content with the image color, then discarded.

4. Fixer - Fix for 3-4 minutes.

5. Hypo - This bath must be made fresh every time you print, agitate continuously, 1 minute.

6. Final water wash. Wash continuously for 20-30 minutes

ources

http://unblinkingeye.com/Articles/Kallitype/K002/k002.html

http://www.alternativephotography.com/process_kallitype.html

http://www.edaites.com/Van_Dyke_Process_1.html


Wikimedia Foundation. 2010.

Игры ⚽ Поможем решить контрольную работу

Look at other dictionaries:

  • kallitype — kal·li·type …   English syllables

  • kallitype — ˈkaləˌtīp noun Etymology: International Scientific Vocabulary kalli (from Greek kalli calli ) + type : a contact printing out photographic process that uses paper sensitized with a ferric salt and silver nitrate and a developer containing borax… …   Useful english dictionary

  • Calitipia — La calitipia o kalitipia (Kallitype en inglés, Callitypie en francés) es un proceso fotográfico antiguo que emplea el oxalato férrico junto al nitrato de plata para sensibilizar el papel proporcionando unas imágenes que toman diferentes… …   Wikipedia Español

  • List of photographic processes — This page list various photographic processes.Color*Chromogenic positive (Ektachrome) **E 4 process **E 6 process *Chromogenic negative **C 41 process **RA 4 process *Dye destruction **Cibachrome **Ilfochrome *Kodachrome **K 12 process **K 14… …   Wikipedia

  • Siderotype — is an iron based photographic print. [http://books.google.com/books?id=J6QRAAAAIAAJ pg=RA2 PA622 dq=Siderotype lr= num=20 client=firefox a] The term was coined by Sir John Frederick William Herschel. [http://books.google.com/books?id=9 sEAAAAQAAJ …   Wikipedia

  • Photographic emulsion — is a layer of light sensitive material coated onto a substrate. In Silver gelatin photography, the emulsion consists of silver halide crystals suspended in gelatin, and the substrate may be glass, plastic film, paper or fabric. In proper chemical …   Wikipedia

  • Opalotype — or opaltype is an early technique of photography. Opalotypes were printed on sheets of opaque, translucent white glass; early opalotypes were sometimes hand tinted with colors to enhance their effect. The effect of opalotype has been compared to… …   Wikipedia

  • Ryan Zoghlin — is an artist and photographer. Biography After gaining a solid technical background in photographic illustration from Rochester Institute of Technology, Ryan explored photography as an art form at School of the Art Institute of Chicago, where he… …   Wikipedia

  • Argyrotype — is an iron based silver printing process that produces brown images on plain paper. It is an alternative process derived from the Argentotype, Kallitype, and Van Dyke processes of the 19th Century, but has greater simplicity, improved image… …   Wikipedia

  • Callitype —  Ne doit pas être confondu avec calotype. Le callitype ou kallitype est un procédé photographique ancien à base d oxalate ferrique donnant des images aux tons sépia. Les images ont généralement une plus grande gamme de tons que les… …   Wikipédia en Français

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”