Sunday, 8 April 2012

Wet Plate Collidion


The wet plate process was introduced in 1851 and by 1860 was the photographer’s chosen process all around the world. The craze continued until about 1880 when the dry plate process came to be. The process is named Wet Plate because it must be coated, exposed and developed all within 15 minutes so the plate will not dry. As the plate dries it loses sensitivity and will not produce an image. Therefore it is necessary to have a portable darkroom or a darkroom close by to where you are shooting.
The Ambrotype (1852-1865) is produced on glass and was commonly backed with a black paint or black piece of material to create a positive image. The Ambrotype can also be used to create negatives.

Ingredients List                                                                                  Equipment:
                                                                                                          -Modified film holders

Silver bath:
-Ferrous sulfate 4g                                                              -Ferrous Sulfate 3g
-Distilled water 100ml                                                         -Distilled water 100ml
-Pure alcohol 6ml                                                                                -Pure Alcohol 6ml
Under RED light:
Step 4: Place collodion coated plate into silver bath. The plate must be placed into the bath in a moderately fast, yet smooth motion. If you stop or hesitate at any point you will create a ling in your emulsion.
Step 5: Remove plate from the silver bath. Wipe the backside of the plate to remove wet silver nitrate. Be careful not to touch the surface of the plate.
Step 6: Place in dark slide.  
The plate is now ready to use in camera!!

Hint: If the plate is left longer then 12mins after being in the silver bath, it will most likely begin to dry and therefore not develop properly. Keep exposure within a 12min time limit.
Wash: 20mins, tray of water, change a few times within this time.
step 1: heat plate on a hot plate or over a flame until the plate is just hot enough that you can no longer hold

step 1: heat plate on a hot plate or over a flame until the plate is just hot enough that you can no longer hold 

-Plain UPS Collidion                                                                            -Sliver Bath       

-Potassium Bromide                                                                           -4x5 Camera & cable release

-Potassium Iodide                                                                               -Lights & studio set up

-Silver Nitrate                                                                                       -Hair Dryer

-White vinegar                                                                                      -Hot Plate
-Ferrous sulfate                                                                                    -Trays
-Distilled water                                                                                     -Red light
-Pure alcohol                                                                                       

-Sodium Thiosulfate

-Distilled water

-Gum sandarac

-Pure lavender oil                                                                                 Equipment for mixing chemicals

-Denaturalised alcohol 100%                                                            -Clear glass and amber bottles,

-Distilled water                                                                                     -Gloves, paper towels, cotton buds, glass beakers and

-Baby oil & Windex                                                                            rods for mixing, scales, hydrometre



Old Reliable
(This recipe is from John Coffers book and is just a rough guide to the recipe if you are interested in what is in the collodion. If you plan to mix the solution yourself I would advice buying Johns book or getting a more detailed recipe. Ellie Young mixed this solution for us.)

Collodion is very flammable! Keep away from any open flame or spark.
Never put Collodion down the sink- it will block it.
Always store in glass bottles- or it will eat away at the container.
Always make sure the lid is tight on the bottle or the collodion will harden (trust me, I know from experience!)

-Cadmium Bromide 1.5gm
-3ml distilled water
-Potassium Iodide 2gm
-190 Grain Proof Alcohol 100ml
-Collodion UPS 120ml
-Ether 50ml

Mix cadmium bromide and distilled water in a glass beaker. Dissolve Potassium Iodide into solution. Add alcohol and stir. This is Bromo-Iodized Alcohol solution

Add ether to collodion in a glass jar. Add above solution. Leave to rest for a few days before use.

Silver Nitrite will blind you if you get it in your eye. Wear safety glasses when working with it! If you do get it in your eye wash it out with water and seek medical attention. (If you get it on your skin it will stain brown and wont wash off for a week or so-a little bit wont hurt)

4x5 plate silver dipping bath (9%)  

-distilled water 400ml
-silver nitrate 36g

Mix the silver nitrate in the distilled water until dissolved. Iodize the bath by either: mix in a pinch of potassium iodide (the bath can be used right away) or place a plate coated with collodion in the bath overnight. Remove in the morning and the bath is Iodized and ready to be used.

Maintenance for the Silver Bath:

Caring for the silver bath is important!
-Before you use the silver bath you must measure the amount of silver in the water with a hydrometer, record the reading (0.06 is about right) because when the silver gets low your images will became faint.
To fix this top up your bath with 28% silver solution

Silver ‘top up’ solution (28%)

-distilled water 50ml
-silver nitrate 14g

Mix the silver nitrate in the distilled water until dissolved. The silver is now ready to use.

-If there is anything floating in the silver bath you can filter it using coffee filters from the supermarket or folding paper towel into a cone shape and passing it though the centre.

-If the silver bath is old and your image is fogging you can ‘sun’ the silver bath by put the silver solution in a brown or amber bottle then place it in the sun for a day. This will remove any ether or alcohol from the silver solution, filter the solution then the solution is ready to use again.   


For positives the developer is more concentrated with Ferrous Sulfate (with less acid in it); for negatives the developer has less Ferrous Sulfate and more acid in it.

Positives:                                                                               Negatives:

-White vinegar 6ml                                                             -White Vinegar 8ml

Mix the ferrous sulfate in the distilled water until dissolved, Add vinegar, Add alcohol and then stir for a min. The developer is now ready to use. The developer only last for month and turn yellow over time. 

Fixer:  (20% sodium thiosulfate solution)

-Sodium thiosulfate 100g
-Distilled or tap water 500ml

Mix the Sodium thiosulfate in the distilled or tap water until dissolved.
Now it is ready to use.

Fix only last for about 15-20 plates


-Gum sandarac 38g
-Pure lavender oil 22ml
-Denaturalised alcohol 100% 220ml
-Distilled water 2ml

Add gum to alcohol in a secure jar. Shake the jar over on and off for a period of a few days, until the gum has completely dissolved. Add lavender oil and distilled water and mix. Filter and it is ready to use.


Preparing the plate:

Your camera should be set up and ready to capture an image before the plate is prepared.

Cut the glass 9.5cm x 12.5cm (to fit in a modified 4x5 film holder)

Step 1: Wash glass in hot soapy water then wash in hot water until there is no soap left on glass. Dry the plate.

Step 2: Polish the plate to remove any water marks (using a small amount of alcohol on a paper towel).

Step 3: Coat plate with collodion:

Holding the plate in one hand (there are a variety of different techniques to do this, you just have to find the most comfortable for yourself), use the other hand to pour collodion onto the plate.

TIP: Pour onto the 1/3 of the plate closest to you, aiming to fill up this whole area with solution. Carefully tilt the plate from left to right to cover the bottom ½ of the plate. Them tilt to the top right corner and finally to the top left where the excess collodion is poured back into the bottle. All this must be done within approx 30sec otherwise the solution will start to dry.

NOTE: this is a very difficult part of the process to get a handle on. Practice with baby oil. Its better to pour on more than less collodion, as if the plate dose not get covered you cannot pour on more! If a hole forms in the coating you cannot flow the collodion back over its self to cover it. You just have to live with it.

NOTE: At any time throughout this process (when the plate is wet) you can simply wipe off what you have done and start again.

Plate stays in bath for 3mins (when creating negatives, it is said that if the plate is left in for longer a denser negative is created). 


Exposure time can range from 1sec to 5mins depending on the source light:

Always remember that this process is sensitive to UV and blue light- so some of the best days to shoot outside can be the most cloudy and overcast. This also makes the exposure extremely hard to judge. Some people start by doing a test strip plate, starting the exposure time from 30sec up to 3 mins, to find out where the UV is on that particular day. Yet, also remember that the UV changes rapidly throughout the day! Generally at 10/11am the UV is hight, lunch it reaches its highest point and then towards 3/4pm the UV has drops and it is best to give up for the day.

In the studio/ inside you can use a fluro, or floodlight (with a halogen globe). Each light has a different amount of UV that you will have to discover yourself by doing a few test exposures, but once you know the optimum exposure time, it shouldn’t change (some lights may give off more UV as they get hotter).

Under RED light 

Develop: 15- 20sec
There are two ways to develop the plate.

For beginners:
Place a small amount of developer in tray (enough to just coat plate), place plate into tray making sure plate is quickly and evenly covered in developer. Continue agitating bath for 15-20secs. Pull plate out and place in wash.

Once developer is used once, pour out HALF of the solution in tray and replace this half with new developer. So the tray is ready for the next plate (having half old and half new developer). This is said to produce more contrast in plates.

Free-hand pour:
In this method, hold the plate in your hand and pour on developer in a similar way to pouring the collodion. It is important to keep as much solution on the plate as possible in the 15seconds of development- and the solution must always be moving around the surface of the plate. After 15sec, quickly drain off the developer and put into the wash tray.

Note: if the plate is developed for over 20sec the plate will fog.


1st wash: 90secs in a tray of tap water, change water 2-3 times within this 90secs

Normal light

2nd wash: 90sec in a tray of tap water, change 2-3 times


Fix: 3-5mins, agitate throughout this time.

Final Wash:


Leave plate on an angle to drip dry, or dry using a hair dryer- hold it 30cm away from back of plate, making sure heat is evenly distributed.

Clearing plate (optional):
Clearing the image removes the loose silver on the surface of the tintype and clears the black creating higher contrast in the image.


step 2:then pour the varnish of the plate like you would the collidoin. To get a good coating, hold varnish on plate and count to 10, then pour excess off into a separate bottle. (keep this excess varnish, filter and it is ready to be used again.)
step 3:heat again to cure the varnish, keeping the edge where the varnish was poured off on an angle, to prevent excess varnish from flowing back over the plate.
Varnish is cured when you can touch the surface and it is not sticky.

Note: If the varnish come out dull and flat then the varnish has been coated too thin or the varnish itself has too much alcohol in it.  This was referred to as a ‘dead plate’ in the 19th Century. Fix this by adding more water to the varnish or if it is a coating problem, coat the plate a second time, pouring from the opposite end to which the first pour was done.

Note: Varnish will not be completely dry for at least a day, even though it appears to be after step 3. Make sure not to stack the pates on top of each other during this time, but place some paper between layers, or better yet, don’t put anything on top until the varnish is completely dry.


Chemicals & Equiptment:
ACE Chemicals:
119A Mooringe Ave
Camden Park SA

Gold Street Studios
Ellie Young
700 James Land
Trentham East Victoria

(Ellie is a lovely and extremely knowledgeable woman. I attended her Tintype workshop last year and had such a blast. Her studio is amazing. Her husband also makes pretty much all the accessories you need for the Wet plate process (this is where the silver bath has come from) and they are not too expensive either! Ellie can also supply the majority of the chemicals for the process.)

John Coffer
1236 Dombroski Rd
Dundee, NY 14837
(John is the king of wet plate. He runs workshops on his farm in NY (where he lives like he is from the 18th Century) and has (hand)written an amazing book about the process and everything you could ever need to know (and a little bit more!). Ellie Young’s workshops are based off John Coffers book. )

TINTYPE: Plate prep

Cut the tin 9.5cm x 12.5cm (to fit in a 4x5 film holder)

Step 1: Peal protective plastic coating from tin.

Step 2: If there is any visible dust, blow it off surface of tin.


O’Brien Engineering:
NSW company. Order online.


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