OUR DOTS ARE FAT.

[Dottonedan]

OUR DOTS ARE FAT.

So you think you’re doing fine halftone printing with your films?

Consider the wet film (photo chemical processing) of imagesetters as the bench mark for true halftone sizes. We don’t see those anymore. You younger whipper snappers don’t know what a good dot looks like.



Most Digital film and wet and wax CTS printers are not putting out true size. Even with linierzation, it’s a fat dot.  A 25lpi can be linearized to be accuate, That don’t make it a small dot. That just makes the 3% a 3% (in a 25lpi).



Take the low end Epson 1430 and a 65lpi.  That’s probably closer to a 55lpi of the wet film (photo chemical processing) of imagesetters.  I’m not talking about how pretty the shape of the dot is, I’m talking size.

When I want to do fine halftone printing on film with an Epson 1430, I have to jump to 80lpi to get a good small dot.  People used to say you can’t do 75-80lpi on tee shirts. Thats because some of us were using good films back then. Back in the day, it was harder to hold an 85lpi and print it well, but it’s easier now with our fat digital dots, (like doing regular 65lpi).


Our dots are fat these days.

[3Deep]

So what cha saying my 1430 is a bad azz and I need to try an 85lpi sep? but wait I kind of like those fat dots makes it so easy to burn 

[Admiral]

I've made lithographic and flexographic plates in the past. Those lithographic plates were great quality 20 years ago when I made them.  I'm 35 now. 

As for our I-Image - our separator does lower the opacity of a lot of colors because otherwise we get too much ink - like you said, those dots are fat!

[tonypep]

I am not an old (white slapper but this aging whipper slapping fool wants to know if "fat" is referring to D-Max/D-Min, or  or shape of dot. Even the best I have seen (for textiles) is what I refer to as a "popcorn dot" under a loupe. And they deliver spectacular results. However, I as I am shifting towards fine art and paper serigraphs this may not be acceptable for continuous tone .
All that said, I am working on some translucent wet on dry images with a 10 dots per inch!

[Sbrem]

I also fall outside of the young whippersnapper category, I made our first halftones with a contact screen and tray developed films. It's so easy now compared to that. We'd make 3 different exposures on the film, a highlight bump (no screen) then the main exposure, followed by the shadow exposure, which was done by exposing the film to a 7 watt darkroom light with the yellow filter on it, which would help open the shadows. I got a lot of good info from the Kodak Halftone Guide. I'm OK with today's results, not to mention we don't have a process camera and darkroom anymore.

Steve

[mk162]

This is something I was wondering about with one of our old DTS machines.  The dots always seemed way bigger than 55lpi, more like a 35-40 dot.  I would crank it up to 75-85 if I really needed some great detail and it worked without moire.

This is all now making perfect sense.  I guess never assume one machines 55lpi is the same as anothers.

[zanegun08]

This doesn't even make sense,

As illustrated below, 85 LPI on the left for a 30% black, vs 55 LPI on the right for 30% Black (from photoshop 600 DPI)

Just because you make your dots smaller doesn't magically compensate for gain as the dots end up just as they are described "Per Inch"

If your 55 LPI dots are gaining to be similar to the size of a 35-40 LPI dot, that means you are gaining in percentage and the 30% will be printing like a 40%-50%

Now on the smaller dots, with less margin of error as the dots are closer together, your gain is going to be more extreme and that will look solid once you have gain on films and gain on press

Yes you can do 80 LPI, you can do 120 LPI but you are going to have the same issues with gain except they will be more extreme in the low end and high end as you just made your margin of error smaller...

[Dottonedan]

I am not an old (white slapper but this aging whipper slapping fool wants to know if "fat" is referring to D-Max/D-Min, or  or shape of dot. Even the best I have seen (for textiles) is what I refer to as a "popcorn dot" under a loupe. And they deliver spectacular results. However, I as I am shifting towards fine art and paper serigraphs this may not be acceptable for continuous tone .
All that said, I am working on some translucent wet on dry images with a 10 dots per inch!

Tony, That’s white "snapper".  Not slapper. You kidder you.

[Dottonedan]

This doesn't even make sense,

As illustrated below, 85 LPI on the left for a 30% black, vs 55 LPI on the right for 30% Black (from photoshop 600 DPI)

Just because you make your dots smaller doesn't magically compensate for gain as the dots end up just as they are described "Per Inch"

If your 55 LPI dots are gaining to be similar to the size of a 35-40 LPI dot, that means you are gaining in percentage and the 30% will be printing like a 40%-50%

Now on the smaller dots, with less margin of error as the dots are closer together, your gain is going to be more extreme and that will look solid once you have gain on films and gain on press

Yes you can do 80 LPI, you can do 120 LPI but you are going to have the same issues with gain except they will be more extreme in the low end and high end as you just made your margin of error smaller...

Yes.

Printing from the same output device, I have one set of gain setting for film output for the 45-55lpi.  Then I have another, that is more opened up for the 65-75 lpi.  Don’t we all?

It makes perfect sense. I can open up the mid tones for the 55lpi (and change the positioning of the %) to be further part due to reducing the size. Like Reverse gain.  But that 55lpi at 45% still looks fat even tho,,I ahve open dup the tone and cut back on the % making that dot smaller. It’s a larger dot than a 75lpi at 45%.   But I order to print the higher lpi well, (without issue), we need to compensate and open that up...push dot %’s over so that the range works well (when it gains, it does not merge closer to the point of fill in). It would do this if I just left it alone at the 50% mark.

The higher the line count, the more you increase your chances of fill-in (dot gain) since there are many more dots in a square inch (looking more continuous). This is really why I use higher lpi. For example, when trying to simulate a large area of a consistence fill, (made up of 4 colors). Like a sand color I just did today.  But I had to open up those mid tones more than I would for a 55lpi.

The original point was, that the dots we use today coming out of most machines...is not at a true size (due to the physical capabilities) of the common output devices.

Wet ink (epson digital printers) “build up multiple ink layers” to form the result.
Wet ink (Cts digital printers)     “build up multiple ink layers” to form the result.
Wax.     (Cts digital printers)     “build up multiple wax layers” to form the result.

None of those above, are as exact as the photo chemical processors. That is what would be the bench mark of the most accurate sized dot in any given line screen that we have.

Squint your eyes at your example. Obviously those dots are “smaller”, and there are many more of them. You can start to see the left side (85 lpi forming a more consistent look) than the right. With the dots being smaller, it works better for this purpose. Like file resolution.

Your gain on press and at output is roughly (the same) % of gain wether it be 55lpi or 85lpi.
I feel like you already know all of that, but the difference that I was really pointing out, is that todays what seem to be (cheaper devices) or lower end devices is a better word) that we use for imaging put out a fatter dot than a true dot size.  I call it “true” because I’m referencing those older (more perfect) dots. Maybe they should be called “ the original”good dots. The dots that were photo chemically imaged onto film at 3600dpi or higher. They were reproduced more accurately due to the process used in conjunction with the ability to do so at a much higher resolution than todays output devices. For this reason, the height of the black imaging on film, would be minute or fractions of the thickness as you see imaging devices from wet ink or wax.

Really, our fat dots are our “new” true dot size or our new benchmark. Your 3% is your 3%. These become our new standard. I have just seen the better ones.

Those who has used 65lpi photo imagesetter film know that the imaging of a 65lpi of today, does not compare to that film.

The one thing that CTS and Laser have over the quality of the old imagesetter films is the DIRECT CONTACT onto the stencil, eliminating the glass and the film thickness. For that reason you have better stencil duplication than any film. In this comparison, one would ahve to look at the benefits of a clean. more perfectly round dot and edge of dot...compared to the shapes we get from Epson printers, Wet ink CTs and Wax CTS.

While the Direct Contact of CTS is a game changer, some might feel the shapes of this photo film (dots) being more perfect has a measurable and positive impact on exposure and image duplication (over the benefits of the Direct Contact.  That would be challenging to prove.

For this reason, I believe the LASER at it’s higher resolutions, would be THE closest thing to perfection we have easily available to us today in a price range that we tee shirt screen printers can afford.

Laser has both High Resolution, and Direct Contact. For this reason, it would seem to be THE best quality option. Now that they offer a machine that images two screens at the same time, this makes the production time needed per screen (half as much) when comparing to the time from WAX and WET ink imaging speeds.

[zanegun08]

Please post photo evidence to backup the initial claim.

All it said in your follow up that you are doing more linearization in a roundabout way, I think that this should be controlled at the RIP level / Photoshop dot gain control level, not a turn your dots to 85 LPI and Pray it comes out like 60 LPI, and then actually be tweaking more in the separation to compensate further for the gain you know that's going to happen.

At the end of the day you are spending a lot of time chasing dots, post some prints to show that all these extra steps are worth it, and tell me how it is scalable.

[Dottonedan]

Please post photo evidence to backup the initial claim.

All it said in your follow up that you are doing more linearization in a roundabout way, I think that this should be controlled at the RIP level / Photoshop dot gain control level, not a turn your dots to 85 LPI and Pray it comes out like 60 LPI, and then actually be tweaking more in the separation to compensate further for the gain you know that's going to happen.

At the end of the day you are spending a lot of time chasing dots, post some prints to show that all these extra steps are worth it, and tell me how it is scalable.

 

I can post some images.  Will do that.


Yes, (I do my controlling at the RIP level).  I like to separate, and let my machine to the rest. This streamlines the process of separations in house. I just go in and choose the correct saved curve for the job a hand.


I have already done this work up front, (so that I don’t spend my days chasing dots).


There are some time when I do some additional compensation in the art. More so, due to additional factors for the order. Like knowing what it’s going on and what I’m doing with it or where it’s at in the print sequence. When I do this, It’s not across the board. It’s more like (in an isolated area) where I want to control something for a specific reason. For specific areas, It's easier to do it on the fly in the file.

[Dottonedan]

Well, I can post (what I do), but I can’t really post comparisons, since we don’t print two jobs with the same content, with one at 65lpi and one at 75lpi. Never a reason to.

[bimmridder]

Hmmmm, someone here once told me, "We're just printing T Shirts."  Not that I agree though

[Dottonedan]

This is a 75lpi. It would have been better as a 6 spot color job, but I need to run it on this 5 color press. So I needed to simulate this, but it had these very large areas of solid color.  I would not want to do that at 55lpi. The dots would be vert fat straight out of the printer.


By upping the LPI making it a smaller dot (and using a curve in the RIP to open up the mid tones of the 75lpi, It presents a much smoother, more continuous look to it. Still, a bit grainy over using a solid spot color, but far better than if Iw ere to use a 55 or 65.  It could look a bit better if at 85lpi, but Didn’t need to push it that far.


If I were to use Wet imagesetter film, at 75lpi, it would look far better with smaller (more accurate dot sizes) in comparison. But I don’t have a wet film imagesetter to show.


This 75lpi of of my Epson I would say is similar to the same size of a 65lpi on a Wet film imagesetter.  But no, I didn’t measure one to the other and compare.  Just looks fatter.

[Dottonedan]

Please post photo evidence to backup the initial claim.

All it said in your follow up that you are doing more linearization in a roundabout way, I think that this should be controlled at the RIP level / Photoshop dot gain control level, not a turn your dots to 85 LPI and Pray it comes out like 60 LPI, and then actually be tweaking more in the separation to compensate further for the gain you know that's going to happen.

At the end of the day you are spending a lot of time chasing dots, post some prints to show that all these extra steps are worth it, and tell me how it is scalable.

 

I just re-read your last post.


I don’t think I’m doing anything elaborate”. Pretty common stuff. I’m not doing any special “Linearization” each time.  I just did a few test way back, have a saved setting, and I apply that as needed. Like before I print, I move up to Accurip, Change the dot gain control and off I print.  No Hokus Pokus going on. No chasing of the tail.  And you are right. Control it at the RIP.  No Praying. Just calculated steps towards my already pre determined end game based off of past positive experience.  Again tho,  I don’t need to do any additional tweaking in the seps themselves.  I might have confused you with the way I worked my post or I’m just not good at getting my message out. LOL.
My wife recently told me she can’t follow my post and that I’m all over the place.  I dunno, I like apples.