This is the SAATI LTS photo results.
This is a stencil on 110 mesh at 847dpi (dots per inch) using phu emulsion. Documents are attached.
It looks to me, to be about the 75% range or (shadow range) and the other photo, being the highlight range or 25%. I’m not sure (wasn’t given the halftone LPI). But to work on a 110, it would be in the areas of 22lpi to 30lpi. Some might push that higher into the 35-40 dpi if there were not dots smaller than say 25% tone.
I would assume there is no issue to be considered with any type of emulsions for LTS, but that’s an assumption. Like wet ink, and wax ink, as long as you have your coating and exposure times correct for a properly cured stencil, there should not be an issue using any method of CTS machine.
This photo, is demonstrating super tight, (and by that I mean very clean, almost perfectly round dots and nearly smooth on emulsion edge/wall). As I suspected, due to the chemical makeup of the emulsion, it’s not 100% perfectly smooth on the emulsion wall, but it does put it in the category of quality coming from a silver based imagesetter (at a lower resolution of say 1200dpi-2400dpi. The results would be very similar due to emulsion particles.
With the 600dpi printers, there are areas of the WAX and WET ink 1-7% range that are in question with those two. Wax, being a little heavier in those ranges and wet ink being thinner, represents the ugly and almost disappearing 1% dots more accurately. Therefore, due to the more liquid state of the ink, is more capable of showing it’s ugly side of the 600DPI output. You’ve seen those little broken up areas of the 1, 2 and 3% dots in the tif files. As you look in the preview window, of either WAX or WET machines, you see the ugly makeup of the smaller 1-7% dots in the wax tiff files or in the PRT files of wet ink. Both are at 600dpi. Both are ugly and one in the same quality (at this stage).
When projected front eh print head onto the screen, this is where the difference comes out.
NOTE: Printing a 1-3% dot on the shirt is not the goal here in this case. It's not going to happen easily with mesh interference, (threads blocking out the dots at that size) but for conversations sake, lets use the entire 1-100% tonal range as a bench mark or target for determining the detail of (machine output). you can get a 1-2% dots to print on the screen or film...and you can even resolve it (get it to wash out) in the screen, but it will be blocked out by mesh thread on press.
Those small dots between 1-7% are representations as best a 600dpi can put out. Higher resolutions, form these minute areas more accurately but most outside the LTS machines are generally 600dpi with one that has come out with a 1200dpi wax machine. The visual and impactful negative side of wet ink, between 1-7% roughly, is that it - can translate this onto the screen more accurately. It’s more of a WYSIWYG or closer to, yet still not able to duplicate what you see in the file with 100% accuracy due to things like head voltage, (humidity levels), projection distance, chemical state and print speed.
You don't see this issue as much with wax in those small 1-7% ranges. Wax is a bit thicker, and therefore, cannot duplicate the ugly dot that is lacking shape information (stemming from the 600dpi resolution). It disguises it as a round shape. In both cases, (both types of machines), since they are using the same data coming from the computer, it’s reading that there is some small information (and it’s trying to physically put some data transfer there in that location. For wax, this comes out as a very small blob, while with wet ink it’s a few speckles of pico-liters of ink. This result for wax, is a benefit to printers as the wax puts down more of a rounder dot there. It puts “something there” that ends up being round(er) than wet ink. In both cases, (at these lower halftone ends of a gradation or a consistent fill of such areas as 1-7% roughly, it seems as though you cannot calibrate your output accurately (in those areas) using a densitometer . Both have finite capabilities at 600dpi.
For these reasons mentioned above, I’D REALLY LOVE to see and show the LTS results in these areas of question. The 1-7% dot range of a 55lpi halftone (on a 305 mesh) at a common angle such as 22.5 degrees with an elliptical dot shape. I’ve sent a request for those and waiting to hear back.
I'm a bit confused that they made mention of the 857dpi (dots per inch) output resolution. I’m sure it’s my ignorance of the use of laser. Perhaps they can elaborate on that for us.
