Emulsion for LED?

[farmboygraphics]

Trying to dial in my new LED light and having a bugger of a time exposing dots under 6%.
Currently using Ulano Orange 1 and 1 sharp side on 300 mesh 55 lpi
Maybe I just need to spend the weekend making screens until I find it? Ugh.
Any recommendations on emulsion?
Edit: printing plastisol

[Rockers]

We like this emulsion from CCI
https://ccidom.com/prochem-reg-lxp-l-e-d-optimized-emulsion

and we like this Ulano emulsion even more
https://www.ulano.com/trifecta

[StinkyDaddy]

I'm using Trifecta and like it.

[Dottonedan]

Trying to dial in my new LED light and having a bugger of a time exposing dots under 6%.
Currently using Ulano Orange 1 and 1 sharp side on 300 mesh 55 lpi
Maybe I just need to spend the weekend making screens until I find it? Ugh.
Any recommendations on emulsion?
Edit: printing plastisol

To me, I don't know why people don't just use the same emulsion they have been and adjust their halftone output. I mean, if what you are not getting is only 5%, 4% and 3% and knowing that 3% is the most feasible small dot to achieve, then you are only talking about adjusting between 7 and 3%. In the curves in the RIP, make your 3% a 6 and slowly ramp up and level out apples to apples at 10%.  I mean, who's going to turn your order down for holding too much in the highlights?
 
This is what shops do or should do, when they have a weak or not so strong of an exposure unit like flo bulbs. You don't fight the bulb or change emulsions but compensate in the output so that what your bulb does hold, is there. Like taking a 65lpi down to a 55 in order to hold more small dots. Or even a 55 down to a 50.  Or beefing up your small dots (in the adjustment) at the 10% range and below so that you can still hold a 55 or 65 across the board but the smallest, hardest dots are more able to be held.

It's true that it's possible to hold (inkjet) film down to the 3% dot or even 2% as Pierre had done in some of his SGIA and ISS award winning prints (when fully calibrated) using a densitometer, and people use densitometer results as a gauge of "true halftones".  But remember, or be aware, that it's comparing/referencing that tone against the other tones (in that particular output devise).

The 5% tone (dot size) in a 55lpi with inkjet (from one brand film printer) will not be the same size 5% tone (dot size) in a 55lpi dot when compared to a different wet ink film printer or when compared to A 5% tone (dot size) in a 55lpi of a SAATI laser dot.  And again, the 3% dot size of a true wet film imagesetter will not be the same size at the 5% dot of a laser.  Sure, we are talking microns in difference, but literally not the exact same.  That quality is all based on type of output and device output resolution. As we already know, Emulsion type is only one factor in holding small dots.


I once had to create a custom curve adjustment for all seps for a SAATI laser customer who could not hold anything below 20% dots using their standard install default settings. At that level, accommodating for losing below 20% still did not provide great results since much was finagled in the finer details but they were able to get the jobs done. They (SAATI) have since changed that and now custom calibrate to all shops who request it. It takes a few days longer. I think maybe even if they do not request it, it's now calibrated to hold 3% in a full 65lpi.  I guess they imagined that most shops would not need that or not really do full 65lpi tonal range?  But at any rate, that's supposedly fixed now. But there I go, drifting off track.

[farmboygraphics]

Trying to dial in my new LED light and having a bugger of a time exposing dots under 6%.
Currently using Ulano Orange 1 and 1 sharp side on 300 mesh 55 lpi
Maybe I just need to spend the weekend making screens until I find it? Ugh.
Any recommendations on emulsion?
Edit: printing plastisol

To me, I don't know why people don't just use the same emulsion they have been and adjust their halftone output. I mean, if what you are not getting is only 5%, 4% and 3% and knowing that 3% is the most feasible small dot to achieve, then you are only talking about adjusting between 7 and 3%. In the curves in the RIP, make your 3% a 6 and slowly ramp up and level out apples to apples at 10%.  I mean, who's going to turn your order down for holding too much in the highlights?
 
This is what shops do or should do, when they have a weak or not so strong of an exposure unit like flo bulbs. You don't fight the bulb or change emulsions but compensate in the output so that what your bulb does hold, is there. Like taking a 65lpi down to a 55 in order to hold more small dots. Or even a 55 down to a 50.  Or beefing up your small dots (in the adjustment) at the 10% range and below so that you can still hold a 55 or 65 across the board but the smallest, hardest dots are more able to be held.

Dan, I appreciate the response.  I had a feeling this is what I needed to do, but to be honest, I don't know how or where to do this. I'm going to say that all these years I've printed halftones I've
just had dumb luck that it's worked out. A lot of jobs this year are leaning towards either sim or process, everyone wants full color now. I've never needed to mess much with curves and levels to get where I need to be. When you say to "beef up the dots in the adjustments" I have no idea where you're referring to. I'm sure I sound like a first year newbie, but I've always just let any sep software I was using do the heavy lifting.  I've run through countless youtube videos, but all of them are under the assumption that the viewer isn't someone with their head up their backside.

[CBCB]

To me, I don't know why people don't just use the same emulsion they have been and adjust their halftone output.

This is what shops do or should do, when they have a weak or not so strong of an exposure unit like flo bulbs. You don't fight the bulb or change emulsions but compensate in the output so that what your bulb does hold, is there.

As we already know, Emulsion type is only one factor in holding small dots.

Spoken like a true artist, haha! Sounds like OP got a new light source? The lack of dots is a symptom of the problem but not the actual problem.

You don’t choose emulsion for resolution, at least not as the first step. It starts with your light source. When you change your light source it’s totally reasonable to expect your same emulsion to not perform the same way, hence the dot issues.

The answer to your hypothetical question there is that people don’t just calibrate their dots when they get a new light because they would be skipping the most important foundational step - choosing the right emulsion for their light source.

I had a respected emulsion tech recommend me a whole new exposure unit to make my emulsion work. Matching up the equipment to the emulsion, instead of just recommending me the correct emulsion? I was literally using the WRONG emulsion for my light source, creating a situation where I could change my RIP all day and still have a crappy screen.

All that is to say is that I understand your Blindspot and why you would be wondering what you’re wondering. Even veterans who do consulting in our industry don’t understand that you start with the light source! It’s a common oversight.

To answer OP, I’m using Saati PHU with Diazo! That diazo slows down the process a little, letting the LED fully penetrate the emulsion instead of just zapping it for three seconds like some superfast emulsions.

[Evo]

I've run through countless youtube videos, but all of them are under the assumption that the viewer isn't someone with their head up their backside.

Halftones are an educated endeavor. Before you dive into Youtube, read up on halftones and how and why they have been used for decades in the printing industry (not just screen printing).

Remember that halftones are way way to represent continuous tones with amplitude modulation (AM). The frequency of the lines (LPI) stays consistent, and the amplification of the dots (dot size) modulates.

When you got to "beef up" a dot, you are increasing the amplitude in a given range of tone. A tone "curve" adjustment allows you to adjust the amplitude in a given tone region - ie make the highlights, midtones or shadows lesser or greater in amplitude.

All of this happens AFTER the light source and emulsion are matched correctly! You need to know what wavelength or range of wavelengths (405nm?) the LED is producing, and choose an emulsion that is optimized for THAT wavelength.

Need to work with a very specific emulsion? Pick an LED that can make the right wavelength and has the power to punch through the EOM.

Then....TEST TEST TEST. Multiple exposure tests of all mesh counts.

Once you have your exposure DIALED and you are producing durable, properly exposed screens that reclaim easily, then you approach curve adjustments to fine tune the dots you want (or hope) to hold.

[Nation03]

I used Ulano Orange with an LED unit. Honestly, I have no idea what % I'm getting. I usually use between a 45-50 dot size. The smaller dots don't washout but I never had any complaints or anyone notice enough to tell me lol. That said, I don't do much halftone work.

[farmboygraphics]

Thank you for the replies 
I got a recommendation for Kiwocol PolyPlus S Diazo and was blown away by the detail I held.
Washed out 2% dots on a 60 lpi with no problem on a 300 mesh 1 and 1.
I'm looking forward to the seasonal slow down so I have a chance to dial this in, along with tightening up my screen room and the rest of the shop.
Kind of excited about doing more process jobs. 

[Admiral]

Thank you for the replies 
I got a recommendation for Kiwocol PolyPlus S Diazo and was blown away by the detail I held.
Washed out 2% dots on a 60 lpi with no problem on a 300 mesh 1 and 1.
I'm looking forward to the seasonal slow down so I have a chance to dial this in, along with tightening up my screen room and the rest of the shop.
Kind of excited about doing more process jobs. 

We've been using the Kiwocol Polyplus MP for several years and get great results with that.  I couldn't imagine needed more!, but the S sounds like it holds even more detail.

We do have Murakami SP-1400 emulsion we rarely use but usually for water-based inks and the detail it holds is crazy to me.

I haven't found emulsions that "don't work" with LED, as that is what we have had for 10 years now.  I haven't been able to use 1 emulsion for everything, we have 2 we use all the time and the SP-1400 for water based printing.  I think it's best to use 2 and have it work out better for the mesh counts anyway though.

[farmboygraphics]

Question on the Dual Cures, I see the recommended time to use once mixed is 4 weeks.
If you're getting close to that deadline do you use it on your lower mesh counts just to finish it,
or does coating screens with what you have left extend that time once it's dried?

[3Deep]

As long as you don't expose them to any light source they will last a very long time, I know I've coated dual cure and didn't use the screens for a few months, if you have to put them in a black garbage bag.  As far as mesh count coat whatever you need and they still should expose even after a few months you might have extend your exposure time a little or maybe not at all.