How calotypes work
The sensitive element of a calotype is silver iodide. With exposure to light, silver iodide decomposes to silver leaving iodine as a free element. Excess silver iodide is washed away after oxidizing the pure silver with an application of gallo-nitrate (a solution of silver nitrate, acetic, andgallic acids). As silver oxide is black, the resulting image is visible. Potassium bromide then is used to stabilize the silver oxide.
In the case of salted paper, the sensitive element is silver chloride formed when the salt (sodium chloride) reacts with silver nitrate[1]. Silver chloride decomposes when in contact with light forming silver and chlorine evaporates. Excess silver chloride is washed out of the paper and the silver oxidizes in contact with gallo-nitrate. The silver oxide is stabilized on the paper with hyposulphite of soda.
Silver chloride is sometimes favored over silver iodide because it is less sensitive to temperature. During long exposures in direct sunlight the temperature on the paper can be quite high.
The calotype created a negative image on the silver iodide from which positives could be printed (onto silver chloride paper). This made the calotype superior in one aspect to the daguerreotype which only made one positive image (whereby it was difficult to get multiple copies)- Wikipedia quote
These are just a few of Fox Tabots images,
for an experiment i thought i would try Cyanotype. I tryed both ways of doing this i did do flower pressing and cutting up paper and trapping them in a photo frame. I also thought i would try this excrement using negatives but instead of using my Large format Negatives i made digital negatives using Photoshop converting them into black and white then inverting them. then printing them onto projecting paper. and these are my end results.
And this one is of the digital Negative. 
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