Step 3: Negative

The cyanotype process is a negative photo process. Black on the negative becomes white in the final print.

I loaded my digital pictures into photoshop. Removed the color information (for a B&W image). Did image->invert for the negative.

The negative can be printed on an inkjet, laser printer, or copy machine. I printed my negative using an inkjet printer with inkjet transparency sheets. I used "high quality black and white" mode (which uses the color inks to make B&W). I did this because the colors are more UV-resistant than the black (in my experience, I make positives for doing UV/foto printed circuit boards that need very high accuracy).

The negative was placed with the ink against the paper. This is the same thing I do for PCBs - it really helps prevent unwanted light leakage.

The paper and negative were placed in a cheap picture frame to keep everything flat and aligned.
<p>I'm guessing that it would be difficult to use this in a pinhole camera setup? or a DIY camera?</p><p>I'm mostly interested in this for making botanical prints.</p>
I found a Dutch supplier: www.hekserij.nl
Just tried the print (managed to get chemicals after a lot of trying!) Wonderful! I just used stuff like keys, leaves and got lovely prints. <br><br>Problem I am facing is in making sure the mix gets spread evenly all over the paper. Tried with 1/2&quot; thick brush, reasonably good, would like better solution. Squeegee? Ink roller? Any ideas?<br><br>Sitaram<br><br>
How much of the sensitizer do you need to cover an A4 size paper? I cannot get readymade cyanotype paper in India, but should be able to get the chemicals. B R Sitaram, Ahmedabad, India
No much, just a very light brushing.
so, when you made your 5ml + 5ml of solution, was it adequate for 1 A4 sheet?
I've heard this process works on wood as well? Do you think it'd be plausible to do a cyanotype on say a guitar then finish over it?
Fantastic idea. I would guess, I did it to an (Instructables) shirt. You'd need to be able to wash it.
its not like radioactive dude :-)
real nice :D i live in holland as well and i was wondering if by now youve found a dutch suplier for the chemicals, please let me know :D <br />
If you are using caustic soda ,or actually almost any of the chemicals described here you can get large amounts cheap!! At the neighborhood pool supply store,thats swimming pools. I dont know why but it seems that many of my customers and about half of the U.S. seem to want to add many toxic products to their environment! Just check out the shelves at the store sometime.Great instructable though I have never tried any of this stuff but I shall give it a shot
where did u get the chemicals for this from
Bostick and Sullivan is a pretty good supplier
An Australian supplier of these chemicals is:<br/><a rel="nofollow" href="http://www.vanbar.com.au/">http://www.vanbar.com.au/</a><br/>
hey man thanks for the tip, Im in NZ and from ajax finechem here it was gonna cost me $300 odd dollars for 500g of each chemical, but at vanbar its $118 (NZD), less than half the price! chur bro
... and by the way, I've found that the best way to "paint" the paper with the sensitizer is to use a foam brush it'll give you an even coating.
I used to add a BLEACH bath at then end of the process and then rinse it. Yeah, that's common bleach or sodium hypochlorite (NaClO) it will give you a REALLY DEEP BLUE TONE, don't ask me why but it happens, just prepare a weak solution. Try it, you'll be surprised!!! (My formula is little bit more complex than yours but I think it should work with yours too). please tell me if this works with your formula.
I am old enough to remember getting photocopies using this process at school. I don't have pleasant feelings when I see a cyanotype, unfortunately. (I just learned what they call this process from you).
My guess is that what you experienced in school were actually copies made using a ditto machine.<br/><br/><a rel="nofollow" href="http://en.wikipedia.org/wiki/Spirit_duplicator">http://en.wikipedia.org/wiki/Spirit_duplicator</a><br/>
"Both the isopropanol and the methanol found in ditto solvents are toxic substances. These chemicals can cause a host of medical problems when humans are improperly exposed" Now I got an excuse for my bad performance at school.
i'd think that by now you wouldn't need one! who's still quizzing you about your school days?
These things are engraved in my mind. I still remember the classroom and If I concentrate enough I can remember what was the test about.
in my teens i spent weeks trying to make one of these machines work (it was abandoned in an office machine repair place where i worked at the time) after much doing i managed to get negative dark brown and wet copies out of it, but all the fun came to an end when whatever fluids were left in the machine were used up. good times....
hmm tea toning thats pretty good. we usually use dark coffee in our lab. its cheaper than the kodak toner. plus it helps yield a more mellow and evenly toned print. and we dont have the health risks of heavy metal selenium poisioning.
agreed, but the coffee tastes terrible after you tone a few prints...
For those seeking less toxic options, many educational supply houses and hobby shops stock sunprint paper, which is similar if not identical to cyanotype. No scary super-toxic solutions to dispose of! <br/><br/>See <a rel="nofollow" href="http://sciencekit.com/category.asp_Q_c_E_756030">http://sciencekit.com/category.asp_Q_c_E_756030</a> for one example<br/>
They're NOT "super-toxic"! Oh, I give up. Let's go back to discussing improvised explosives, ninja weapons, and homemade weapons. Heaven forbid we should do anything involving CHEMICALS (*gasp*)
too true
is there a cheaper, yet still reliable solution for exposure than a 150$ light box? I know I can use sunlight, but doing that reliably would be difficult. For example, would it be feasible to put a tanning bed light in my bathroom temporarily?
The sun. Obviously. I've many prints using the sun. T-Shirts, fiber paper, etc. Just weigh it down with a piece of glass, and carry it out into bright sunlight. Forget the filters. Just experiment with exposures. You can also see the chemical change as it develops.
Also, if you do your history research, they didn't have electric UV lights in the 1800's. The sun is the original UV source. You can also make Van Dyke prints (brown, different process) with the sun.
I'm not sure what the spectral sensitivity of the cyanotype is but if it's anything like daguerreotypes (orthochromatic: sensitive only to blue and green light), then you could slap a red/yellow/amber filter over the image and then develop using the sun. Are cyanotypes sensitive to the full visible light specturm? You could also, I suppose, buy a UV-only "visible-light" filter to block out all light except UV. That would be pretty sweet but expensive. B+W makes one, I believe.
There seem to be a few options for a normal sized UV bulb (mostly reptile lights). I believe I'll buy one of those and do contact prints until I get up the gumption to try to build my own enlarger. Thanks for the help!
edit: see the image in my instructable or my avatar: I'm developing a daguerreotype using a halogen lamp and a piece of Amberlith.
I'm still partial to using an actual photo enlarger to print with. It takes some tweaking to determine your exposure time, but I've used it succesfully with standard cyano-blueprint paper (available from reprographics stores) There's also the option of just having a large scale b&w negative version of an image plotted onto a semi transparent material like mylar or vellum then using that directly in a blueprint machine to expose your images... A word of warning though... the developer in blueprint machines is ammonia and the first time you use a blueline machine... wooboy are your eyes going to water.
I used a 5 euro face tanner from a second hand shop. Its worked great for PCBs for over a year now. I don't know if it gets cheaper than that (the sun I guess...).
I had a little extra stuff left so I tried to cyanotype my instructables t-shit. It worked pretty well.
Does this wash out of fabric? If not, oh, how cool!
Yeah, it _mostly_ washed out. After dozens of washings you can still make out that it was there and what it was, but nothing like this. I've also tried cloth napkins (great gift idea, if it worked...) with little success.
Perhaps if you heat press it before washing, like you would with screen printing.
Two other suggestions, borrowed from some dying sites:<br/><br/>1) Use a <a rel="nofollow" href="http://en.wikipedia.org/wiki/Mordant">mordant</a> to make the Prussian blue penetrate the cotton fibres better. Mordants include alum, ferrous sulphate, copper sulphate and tannic acid (tea bags!). <a rel="nofollow" href="http://www.mspong.org/cyclopedia/dying.html#prussian_blue">This page</a> has a recipe for Prussian blue on silk, which might work for cotton as well.<br/><br/>2) Commercial dye fixatives such as <a rel="nofollow" href="http://www.pburch.net/dyeing/FAQ/fixative.shtml">Retayne</a> may help keeping the dye in the fabric during washing.<br/>
Nice t-<em>shit</em> and nice instructable. lol<br/>
hey everyone!<br/>does anyone know if the Ferric ammonium citrate can be replaced by the iron sulfate??....I saw something about it but can remember the web site. anyway im trying to use the basic formula but it is not working with the iron sulfate. and the Ferric ammonium citrate is a bit expensive here (in portugal).<br/>help please =) <br/>
Goed werk en een prima beschrijving !
Hello, I've been reading this and many more articles about Cyanotpyes.<br/>First of all, there is a great article on washing cyanotype clothing at<br/><a rel="nofollow" href="http://www.alternativephotography.com/articles/art097.html">http://www.alternativephotography.com/articles/art097.html</a><br/>and also, you might want to check out &quot;cyanotype rex&quot;, which is much faster and its possible to take photograph negatives directly:<br/><a rel="nofollow" href="http://www.f295.org/Pinholeforum/forum/Blah.pl?b-apd/m-1137519426/">http://www.f295.org/Pinholeforum/forum/Blah.pl?b-apd/m-1137519426/</a><br/>
Hello there ! this is just too cool but since unless mistaken you sound as though not so far from me ;I am based in Belgium/bruxelles and would like to try out this ,could you direct me or refer some product brands in order to carry out well this project ? please advise
Never knew that before. The color cyan was named after CYANide?
I just found this quote on making K++Fe(CN)6: "To make a long story shorter, it was discovered some years later that potassium ferrocyanide could be formed by treating Prussian blue with potassium hydroxide." (KOH) KOH is also Battery Alkaline. (Beats me why Lye ain't as good.) It often leaks out and is clear and slimey and awfully corrosive to electronics. The Potassium Ferrocyanide Long Story is icky, involving either distilling dead animals... or else messing with "the evil poisonous stuff".

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