Wet plate chemistry is not complicated, but is dangerous. I strongly recommend to prepare your own solutions - it's cheaper and you have control over critical part of the process. You should find a good source of raw chemicals. If you want to produce clean plates, the purity of chemicals is an essential condition.  


Be careful when you are working with chemicals and you should use protective gear all the time.

Find a safe storage out of kids reach. 

Some of wet plate chemicals are highly flammable. 

You should use separate bowls, cups, cones, bottles, spoons for every chemistry. Be careful not to cross contaminate your chemistry. Just pure chemicals results in pure plates.










WARNING: Alcohol, collodion and ether are highly flammable. Avoid open fire. To work with these chemicals, you should have a good ventilation in your darkroom


What do you need


Small glass bowl 

Small glass rod

A candle

Bottle for ethanol-ether solution 

Bottle for ethanol

Bottle for collodion

Protective gloves and breath mask

Grain alcohol                 100 ml

Cadmium bromide         1,5 g

Ammonium bromide         1,3 g

Cadmium Iodide             3,4 g

Ammonium Iodide          2,6g

Ethanol  (96-98% alcohol)  20 ml 

Ethanol Ether  1:1          60 ml

Collodion pure         120 ml

Plastic cone for Iodising solution

Bottle for Iodising solution

Plastic cone for final working collodion

Bottle for final working collodion


Lea’s Landscape is not to easiest to prepare, but I like its quality for landscape, still life and even in portrait photography. Preparing working collodion solution is a two step process. At the first step you prepare Iodising solution, just alcohol mixed with salts. You can store it for a very long time. In the second step you mix working collodion. It has to ripe for at least three days before use. The final working solution is deteriorating with time. It is loosing sensitivity and its contrast is increased by loosing details in shadows. I prefer to work with fresh collodion, but I often mix it with a bit of an old batch. More about this later.

I’m storing ether in 1:1 mix solution with alcohol - it should be more stable then pure ether. You can store it outside of your house, It will not freeze. (Diethyl ether freezing point is -116 degrees of Celsius, 96% ethanol freeze around - 100 degrees of Celsius)



1. You have to dissolve salts in distilled water, but you should minimize the amount of water you are using. Fill the glass bowl with 6 ml of distilled water

2. Dissolve in the bowl Cadmium Bromide. Use small glass rod for mixing. If necessary, you can heat a glass bowl over a candle flame

3. Dissolve in the bowl other salts. Ad new salt only after previous one is fully dissolved

4. Set plastic cone on bottle for Iodising solution

5. Fill solution from bowl into cone

6. Fill measure cylinder with 100 ml of ethanol

7. Fill ethanol into cone. Be careful to wash with ethanol all salt solution from the cone into the bottle.



1. Set plastic cone on the final collodion bottle.

2. Fill the bottle with 120 ml of collodion. (I have a special small bottle for pure collodion, with marks for 120 and 240 ml)

3. Fill the bottle with 40 ml of Iodising solution

4. Fill the bottle with 60 ml of ethanol - ether 1:1 solution

5. Fill the bottle with 20 ml of alcohol

6. Tap bottle, mix it and let it stay for a few days.

Fresh working collodion can be milky. It will clear (or rip) in a few hours or days. Fresh collodion is very sensitive and it can produce very flat overexcited images. 


How does it work

Collodion is mix of gun powder, ethanol and ether. Very flammable solution, be careful how you store it and especially when you are traveling with it. 

Collodion is just a base, emulsion, which will create a film layer on plate. Salts in collodion are what is important. Bromides and Iodides from collodion will in Silver bath create light sensitive halids. You can change sensitivity and contrast of working collodion by changing the amount and composition of different salts in Iodising solution. You can lost a high amount of time and other sources that way. I prefer to stick with a standard recipe. Much better way how to deal with the contrast in wet plates is careful manage exposure time.

I have tree bottles of working ripped collodion. Number one is marked new and is filled fit the newest, just ripped batch, usually no older than a week. The second bottle is filled with collodion I’m actually using for plates. The third bottle contains collodion I use to catch collodion from plates when I’m pouring collodion on them, its accumulated “old collodion” 

I often mix into the second bottle fresh collodion from the first bottle and old collodion from the third bottle (not more than 10-15% of old collodion). For regeneration of old collodion you can add into it up to 20% of ethanol-ether 1:1 solution. 

Never fill old collodion, you don’t want to use anymore, in your sink. It can to choke it easily. 

Woking collodion in the second bottle should be always filtered.

You can use denatured alcohol for cleaning collodion bottles or cans - it's much cheaper then clean them with pure alcohol. 




WARNING: Never ever do anything with Silver Nitrate or silver bath without glasses. 

If you are doing wet plate and not use KCN as a fixer, silver bath will be the most dangerous thing in your darkroom. SILVER NITRATE, AgNO3,  is a very aggressive chemical. Be very careful with it. Your eyes should be protected all the time you are working with AgNO3. Silver Nitrate in your eyes can blind you easily. Silver Nitrate will darken every organic material, your clothes will be irreparably destroyed. Dark spots from fingers will diminish in days, take them as the mark of your profession. Consider a safe storage option, especially if you have kids in the house. Be careful with this bastard. 


What do you need


500 ml graduated cylinder

Plastic cap for Silver Nitrate

Plastic cone for Silver Nitrate

Protective nitric gloves and glasses

1 litter of distilled water

90 grams of Silver Nitrate AgNO3



1. Measure in plastic cup 90 g of Silver Nitrate, AgNO3

2. Fill 500 ml cylinder with 500 ml of distilled water

3. Set plastic cone on 1 litter bottle

4. Pour Silver Nitrate from plastic cup into plastic cone

5. Slowly pour water from cylinder into cone.  Take care to wash all Silver Nitrate grains from cone into bottle

6.  Fill cylinder with 500 ml of distilled water and pour it into bottle


How does it work

When the plate with collodion layer is dipped in Silver Nitrate bath, salts from collodion (iodides and bromides) are reacting with silver and creating light sensitive halides. You can check progress of silver bathing by visual inspection. (You have to use safe light) Colour of collodion on the plate is changing from transparent to milky. Plate should be in a silver bath from 3 to 5 minutes. 

Fresh silver bath has to be iodised before use. Just prepare on a glass plate with standard collodion and let in in silver bath for a night (You should use at this stage glass plate, not tintype).  

Be careful not to contaminate your silver bath with tap water. When you are washing your silver bath tank, you should use distilled water for the last rinse. 


Silver bath maintenance

You should check specific gravity of fresh bath with a hydrometer and write it down. You will use it later for silver bath maintenance

Rule number one - filter silver bath after every photo session. 

Silver bath in use will is contained with organic remnants and with ether and alcohol from plates. The solution is sunning. Pour your silver into a bottle with very wide neck. Cover it with any breathable cloth and let it stay in sunlight for a few hours. I prefer to make sun bath as often as possible, at least twice a week

I regularly refill silver bath with a fresh solution. Your silver bath would stay in working condition for very long time. The best sign that silver bath is losing its power are dark dots (black holes) clearly visible in light parts of the plate. 

From time to time you can control specific gravity of your silver bath and add a distilled water, if it is too high or silver nitrate, if it is too low.

I’ve never played with acidity of my silver bath solution. I’ve never ad an acid into my silver bath. I prefer to avoid heavy maintenance as long as possible. (But from time to time I check pH with paper test strips) 

Boiling of Silver Nitrate bath can be really dangerous because of a poisoned vapour and has to be done outside. 

If you have a problem with your plates, there is a big chance, that your silver bath is NOT the source of problem. I have three contemporary wet plate photography manuals, written by Quinn Jacobson, John Coffer and Mark Osterman. (Every of them is a valuable reading) I think it was in a John Coffer's book, where is the sentence - if you have technical problems with your plates, the silver bath is the least likely source of them. Before you start to do something with your silver bath, check everything else.







What do you need



Plastic cap for Ferrous Sulphate

100 ml graduated cylinder

500 ml graduated cylinder

1 litter bottle for developer (can be plastic)

Plastic cone for developer


500 ml distilled water

20g Ferrous Sulfate (FeSO4)

20 ml Grain Alcohol

15ml Glacial Acid (Acetic acid, CH3CO2H)


Protective acid resistant gloves and glasses


1. Measure in plastic cup 20 g of Ferrous Sulphate

2. Fill 500 ml cylinder with 500 ml of distilled water

3. Fill small cylinder with 15 ml of Glacial Acid 

4. Pour ACID from small cylinder INTO WATER in big cylinder. NEVER EVER DO IT IN OPPOSITE DIRECTION!

5. Fill EMPTY small cylinder with 20 ml of Grain Alcohol

6. Pour alcohol from small cylinder into water-acid solution in big cylinder

7. Set plastic cone on 1 litter bottle for developer

8. Pour grains of Ferrous Sulphate from plastic cup into plastic cone

9. Slowly pour water-acid-alcohol solution from cylinder into cone.  Take care to wash all Ferrous Sulphate grains from cone into bottle. If Ferrous Sulphate grains are caked, joust pour a bit of solution into a cone and wait. Cooked grains will break after few seconds.

10. The developer should be filtered before use. 


How does it work


Ferrous sulphate is an active part of the developer. It’s cheap, you should use pure chemical quality of it all the time.  

Developing is very fast and abrupt reaction. Acid works as a retainer, which help to increase developing time up to 20 seconds. 

Alcohol is decreasing viscosity of developer and helps to spread developer fast and evenly over the plate. 

Developing of plates is a very fast process. I’m using for pouring of developer on a plate a spirit glass, holding the plate in the left hand. Highlights should be visible in seconds. You should stop developing - poor water on your plate - in the moment, when you can see mid tones. I consider as a good exposure the plate with 15-18 seconds of developmnet time.

You can use developer when Ferrous Sulphate is fully dissolved. I prefer to mix developer at least a day before using. New developer is blue. Older developer will turn its color into orange. It will lose its power with time, but it will work fine. I prefer to use at least a week to four week old developer. After one month I dispose it. The developer should be filtered before using. 


Summer Developer for temperatures above 30 degrees of Celsius


500 ml distilled water

20g Ferrous Sulfate (FeSO4)

30 ml Grain Alcohol

20 ml Glacial Acid (Acetic acid, CH3CO2H)





I’m using for tintypes 20% solution of Ilford Rapid fixer with distilled water. The fresh solution works pretty fast and is slowing down in time. Fixing time at least 5 and no more then 10 minutes





WARNING: Sandarac Gum Varnish is flammable. Avoid using open fire with it.


What do you need

Glass bottle for “Baby pool

Glass bottle used for stock varnish

Small glass bottle for working varnish

400 ml of Grain Alcohol

60g Gum Sandarac

40 ml Lavender Oil ( never use cosmetic oils)

8 ml of distilled water

Plastic cone for varnish



1. Put sandarac, alcohol, lavender oil and water into “Baby Pool” bottle. Mix it for a few minutes and let it stay for at least three weeks. You can mix it again from time to time, but not at the last three days before the next step

2. Carefully, drop by drop, filter dissolved solution from the “Baby Pool” bottle to a stock bottle

3. Before real use, carefully, drop by drop, filter varnish from the stock bottle in the working bottle. 



How does it work

Sandarac Gum is dissolved in alcohol. Lavender Oil is necessary to add some flexibility to varnish layer on a plate and it helps to avoid cracks. By adding a small amount of water - just 8 ml to 400 ml of alcohol - you can eliminate the risk, that varnish will dissolve collodion and wash it from the plate.

The trick of varnishing is to evaporate of water from varnish on the plate before it dried. You need a heat source. I prefer to use hear dryer. 

Before varnishing I heat plate to the temperature I’m able to hold in bare hands. You can pour varnish on the plate in the same way as collodion. Varnish flows on the hot plate very fast. Exceeded varnish should be poured from the plate in the stock bottle without hesitation. 

The pouring corner must be from this point the lowest point of the plate all the time. When drops of varnish from plate slow down to one every few seconds, tap the pouring corner on paper towel.  Start to heat plate as fast as you can, if necessary tap drops from the pouring corner on a paper towel. Heat the plate how much you are able to hold in hands and even a bit more. This is the moment when you have to evaporate all water from varnish. 

The varnished plate should stay freely (before shipping or packaging) for at least 48 hours. For long term storage you have to build an appropriate archival solution.



The books you should know

Quinn Jacobsson: Chemical Pictures

John Coffer’s Manual

Mark Osterman: Basic Collodion Technique: Ambrotype & Tintype



If you are working with wet plate negatives, it is not difficult to prepare and develop dry plates. You have to buy just one new chemical, tannin acid.  It is used in preservation solution you apply on the plates before drying.

Tannic preservation solution
Tannic Acid 3.3 g
Grain alcohol 1 ml
Still water 100 ml

You can use your usual collodion and silver bath. Just be careful with old collodion. Pyro developer shrinks the collodion layer during developing. Old collodion is more fragile and there is a bigger risk of peeling of the collodion from the glass. (Edges of the clean glass plates should be always painted with albumen.)

After sensitising, you have to wash the plate in the sill water bath. After few minutes let water flow from the plate. You have to apply the tannic solution on a still wet plate. I'm floating plate in the same way as with developer, four times, changing pouring side every time.

Now you can let the plate dry in a dark room. Dried plates have very light milk color. Thy can be stored before exposure for weeks.

The exposure time is 3 minutes for EV 14 and F5.6. When inspecting exposing plates in the safe light, you should see a very soft image, when just parts of the image with stronger lights (sky) are just a slightly darkened.

As with all analog photography, there is not a big risk if you overexposure, but you can lose a lot when you underexpose the plates. 

I develop plates in the evening of the day when they were exposed

Before developing let plate soak in a still water bath for a few minutes.


Stock solution #1
Pyrogallic acid 4.7 g
Alcohol 30 ml

Stock solution #2
Silver Nitrate 1.3 g
Citric Acid 1.3 g
Wate 30 ml

For developing you should prepare Diluted Pyro
Stock solution #1      3.7 ml
Water                      177 ml

Working developer should be mixed just before developing
Diluted Pyro             15 ml
Stock solution #2  20 drops

I'm using one or two caps of this developer for 18x24 cm plate. Developing time is 5 - 10 minutes

After washing fix the plate in Hypo.