photo emulsion and screen printing

ok, i'm about to make my first atempt at doing a photo emulsion and i need a question answered...when i print onto the velum sheet (transperancy), i should print in negative? is it all the black or the clear spots that wash away after you apply the emulsion? i'm so unclear about this, it sucks. i looked on the web, but there aren't that many resources, or i just haven't been able to find them. any help would be appreciated.

no. you print it from your computer (because copy machine toner sucks) and the design must be backwards. funny you mention this because i'm going to be making my shirts this week. ha Ha HaH WHARHEFW

GOOD LUCKR943w

and just to clarify....not negative. you want the light to not touch the areas where your design is....so that way the emulsion wont harden where your design is.

ok, that clears alot up, man. i really appreciate that. like i said, first time...heh heh, i'm a print virgin...

well, i hope this comes out correctly. thanks, again.

you want the photo positive...

and it doesn't need to be backwards...

the way it looks on the transparency is how it'll look when you screen it... whatever's black on the transparency is gonna be black (or whatever color you're screening) when you screen it...

dirty's usually right about things, but you do want it to be regular-side-up. print out what it is you want from the computer, then photocopy it onto the transparency. if you're using the silk-screening technique, any sort of grayscale fade won't work well at all. it's best to have a dot-matrix deal or a crosshatch style going on.

negatives are good for screening say, a white face onto a black shirt. you'll have to cut out the excess black on the transparency but this will screen the highlights onto the shirt/black thing letting the objects natural darkfulness act as the shadows.

and don't be afraid to use a lot of ink and squeegee rather hard.

well, if you're using the sun to 'bake' the emulsion, then you do want the photo on the screen backwards. if you're using a light table, put the transparency on the table right side up and put your screen frame on top of that.

pretty much the only way to get shades of gray is to use halftoning.

if you use photoshop its pretty easy to do filters -> sketch -> halftone

bump the contrast up to where there is no gray at all. most of the time you want to go with the dot setting.

you wont ever need to print on to your film in reverse as you can just flip it depending on where your light source is coming from.

+ well, my first time turned out bust. i think i over-coated it with photo emulsion, i'm trying again. i put it on a little more thin this time around and made sure that i got off all of the excess. it's outside the front door getting some sun right now. last time, i only gave it around 7 minutes in the sun, this time i'm giving it about 20. i had called a friend in tampa that does screen printing for a living and asked him about it afte i posted this the first time, he said about 5 minutes in the sun, but he's also in tampa where the sun is alot more bright.

anyway, i really don't know how this will turn out, vynil junkie saw what i was attempting to transfer to canvas, it's pretty detailed. i really hope this photo emulsion will pick it up. thanks for all the input to everyone who has posted.

i just did a bunch of photo emultion printing today, it's pretty easy if you got the right materials. the ocol think about photo emultion stencils is no worries about islands and you can draw your pic the way it's to be viewed (none of the confusing backward stuff.) The best way to get a fade with these stencils is to just have a gradient made with dots, like mroe dots where it's a solid color and less to no dots where it's the paper color, and all in between. Shit goes a lot easier if you draw on acetate or have a lazer printer and print direct to acetate

i just printed to acetate from an ink jet printer. my friend said it will work, but he said in his company they just print to this tracing paper type stuff. he said it has a really light frost on it and it works well. i dunno, i'm just gonna stick with the acetate. they probably have those photo exposure lamps or whatever they're called.

that's a good tip on getting gradients. thanks. i just moved the screen into a bathroom with good lighting, they sun is starting to go down and the outside light isn't that great. i'm guessing it would work outside right now, but i really want this shit to come out. it had been outside for about 15 minutes. i guess i'll actually go try and rinse the shit off now. peace

Originally posted by casekonly

i just printed to acetate from an ink jet printer. my friend said it will work, but he said in his company they just print to this tracing paper type stuff. he said it has a really light frost on it and it works well. i dunno, i'm just gonna stick with the acetate. they probably have those photo exposure lamps or whatever they're called.

that's a good tip on getting gradients. thanks. i just moved the screen into a bathroom with good lighting, they sun is starting to go down and the outside light isn't that great. i'm guessing it would work outside right now, but i really want this shit to come out. it had been outside for about 15 minutes. i guess i'll actually go try and rinse the shit off now. peace

I'm not an expert but i've tested acetate and printers for stencils, and ink jet on acetate isn't good. the ink will most likely rub off, but yeah inkjet stencils on trace paper is cool, just have to expose the silk screen longer i believe. And the stuff your friend is talking about that has a frosty look is basically a different kind of acetate treated for taking ink better. i forget what it's called exactly. I'm pretty lucky, taking a printing class where we have access to a light table etc. but you doin' it in the bathroom is dedication, keep it up.

Also, where do you get the photo emultion, and for how much? ;)

i got the emulsion from a local art store for about 16 bucks. kind of expensive, but i'm really wanting to get this deisgn to canvas. speaking of which, i just tried to clean it off and i can barely see my design. it looks like some of it coming throguh, but not all of it. i think i fucked up again. dammit. i don't know, maybe it's the acetate. thank god i have some tracing paper around here. i'll go clean the screen if this doesn't work and try all over again. i have to learn somehow, right? speaking of which, i just founda good tutorial online if anyone is curious about this stuff

silk screen biz

wish me luck

first make sure the stencil is totlaly opaque and the ligh is ocming from only one side and if possible cover the side the stencil's not on with something black to keep the emultion from exposing to keep your design. once you've exposed it to light and the multion turns a light color, which if you're doing this by indirect bathroom light mught take a while, quickly wach the whole screen which will clear out the non exposed emultion and volia! Also by not using a direct bright light and making the exposure time longer you will most likely lose quality on the stencil, that you can't help unelss you have a special light table

okay, i just cleaned the sreen and totally removed the photo emulsion. i'm going to let it dry while i eat dinner and then try once more for today. i just printed onto tracing paper, and i'm hoping that it will work out better than that damn velum did. i should coat both sides of the screen with emulsion? is that right? i know about covering the other side of it, i've been doing that with some brown wrapping paper (kind of like grocery bag paper). anyway, this isn't starting to piss me off. i'll try to overburn this shit this time. maybe let it expose for an hour and a half since i'm using tracing paper this time. i don't have a sheet of glass to stick on top of the tracing paper, so i guess i'll just tape it down on the screen where i don't have emulsion. the image i'm trying to get isn't that big anyway. gah, i hope this isn't going to take much longer to get the hang of.

you wanna put a ton of emulsion on there... keep coating it on so it's nice and thick but not dripping...

do it in the bathroom with a bright lamp pointed down directly above the screen... any excess light (like sun light bopuncing off the ground) is gonna activate the emulsion under the stencil as weell, tot5ally defeating the purpose...

and check the times on the emulsion; most emulsion you get at an art store and what not has a light time of like 40 minutes to an hour... you can 30 second emulsion and all that but you usually have to got o a specialty store to find it...

woah...i wouldnt goop alot of emulsion on your screen unless you want to double or triple your exposure time.

i coat my screens once. and it takes me about 30 minutes to burn right. not using an exposure unit though just a 1000 watt work light.

also i dont know how well tracing paper is going to work. i use some inkjet transparencies...you want the non-black part of your film to be as clear as possible.

a good thing to do is to do a test exposure where you cover all but a one inch side of the screen with like a piece of cardboard and let it expose for 10 minutes then move the cardboard over an inch and let it get another 10 then again then again then again etc.

different light sources are going to take longer or shorter as well as different amounts of emulsion.

its tricky at first but once you figure out how long it takes its very simple.

okay, i did get the tracing paper to work, but i was unable to capture alot of detail. that sucks.i did a coat on the front and back of the screen, let it dry in the dark, pulled it ouot, and taped some heavy brown paper on the back side of it, then taped the transperancy to the front. i then left it under a light for about an hour and a half. i then washed it with tepid water. i was beginning to think i wouldn't get it right. i didn't, but this time using the tracing paper, i actually saw what i was supposed to see when washing it. maybe some more help woul dbe in order?