This is misinformation on the highest level...I'm curious what "long run consistency" is supposed to do...the printer uses thermal heads that are not designed for long runs at all...I have never had any issues running in 2.5-3 hour bursts and letting the printer sit for 10 minutes before starting next run...HP said the runs can be longer but by doing this I prolong my head usage and have never...oops ever had a color shift or consistency issue.
A piezo head can run all day without this issue...
I am getting on average 7-8 ink cartridges through my printer before changing out heads...
Back to he question at hand my understanding is that the long run consistentcy is supposed to monitor and adjust feed rate, color, and interphase to mamaintain panel size and color consistency between panels.
greysquirrel said:the printer uses thermal heads that are not designed for long runs at all ...
This is misinformation on the highest level...
We are able to print all day and unattended, we run a very specific job on 4 pass and we can get 4 rolls done in a day at 1:50 per roll then we set one up and run it after we leave. That is nearly 10hours of printing and 750 Lin ft and we will do this for week's straight.
These machines are designed to run and those thermal heads when they do run out they are designed to change out. We got the 360 on March 1st and its already got 49L of ink through it and only 2 heads due to jams.
Back to he question at hand my understanding is that the long run consistency is supposed to monitor and adjust feed rate, color, and inter-pass delay to maintain panel size and color consistency between panels.
No need to blame the LcLm-Printhead for every problem. There is a problem with color deviation too when printing long runs with full color with a higher number of passes.
There must be a reason why HP uses now 2 Op-Heads, but still 1 Light head only, with the new 500.
This is an issue caused by having only one lc/lm print head. You can't run 4 pass and use lc/lm inks, so no you would not see this color consistency problem.
Also the long run consistency setting as told to me by an HP representative only affects the the temp and power of the lc/lm printhead.
That is not correct at all, I'm using CMYKcm and 4 pass... so again how is it the LC LM head issue?
It is definitely CMYKcm, I know this for a fact since I built the profile myself.
You don't seem to have much real world experience with these printers as you can't explain what you consider higher number of passes of if full color means CMYKcm or CMYK.
From experience with the 300 machines the 2 OP heads on the 500 are used to prevent ink starvation since these are designed for faster printing
I know what HP has told me ...
If you think light colors would have any effect on full colour prints (for example full red areas), than you do not understand what light colors do. They REPLACE their regular pendants on LIGHT Colour tones, from a defined split level. The only thing what could happen with light colours during such prints that they "starv" in color bars because of they are not much in use during the print. I'm not shure were the ink split level is set on the latex 300 because it is not user editable, but that there is one is shure.
Thats wrong. Look at that video to learn what optimizer does (you only need to have a look on the first 2 - 3 minutes, but the whoie video would be interesting):
You can't deactivate one Optimizer Head on the 500's. You can only set the profile to don't use optimizer at all.
Be shure that really HP speaks to you, not only a sales representative of a dealer wo searches for excuses.
By the way: I have done tests with the "long run consistency mode" yesterday, printing 12m of full colours on paper. The attached PDF shows the difference in colours between a swatch at the beginning of the print and at the end.
Interesting and in opposite to your opinion: it looks like that there is a problem with a Cyan (full Cyan) head, because I have a lot of deviation in colours with cyan ... but a small deviation only with light blue colours. But the light colours were only in use during printing 5 swatches ... the print itself consists of full CYMK-stripes.
"not much use during the print" Your lack of understanding is amazing. As you say you not sure where the ink splits/curves are for the light inks so you don't know how much light inks are used in say the 70% to 100% range in CMYKcm mode.
I know exactly what the optimizer does. Why the use of two optimizer heads? I have never heard a really good explanation for that.
Coming from you, really?
But you didn't do the test in CMYK mode or did you? So do I have to assume you used CMYKcm mode 5 swatches and CMYK mode in the other swatches? So as you say your not sure where the ink splits/curves are for the light inks so you don't know how much light inks are used in say the 70% to 100% range in CMYKcm mode. The only real way to test this is to use both color modes and see what the differences are and in color consistency using one mode over the other, and to use real world print jobs, not just color targets with small patches of various colors.
If printing tests, when knowing what light colors do, you can define the tests that the ink split levels don't play any role. I will proof that during next week, I do not have the printer at home.
More optimizer on the media, together with the more efficient curing module, will allow to put more ink on the media without drying problems or Coalescence. The latex 300 and the latex 500 are not different in print speeds, but with the latex 500 more saturated prints are possible. So, if the highest suggested speed for indoor printing on a latex 300 was 8 Passes, it is now 6 Passes (outdoor printing 4 Passes instead of 6 passes).
I'm not a salesperson.
Standard targets are needed to measure the colors with the Spectro. But of course I haven't printed just a target every 2 Meters, but have embedded that targets into a print.
I have done a "real world test" some months ago, mostly pure red (100/100) over 10 Meters, and had a deviation too.