Profiling on HP 5500 - Max Quality Mode?

[JohnMonad]

I am trying to create profile for Onyx 7.1 on an HP 5500 printer. I am wanting to set it up for the Max Quality print mode, which is 1200x600 dpi. The thing that is confusing me is that in Media Manager, the only mode available similar to this is called 600@1200x600; and the resolution is listed as 600 in both directions.

On other RIPs, the Max Quality (1200x600) mode is about 30% slower than the Productivity mode (600x600), but on Onyx, the throughput is the same, which leads me to wonder if it is really 1200x600?

[el pinguino]

I believe that the 1200x600 is refering to the double strike. I think.

[pscala]

That is right, the 5500 does not do a true 1200dpi, as is reflected in the MM. HP has used the double strike thing for seveeral years to get a higher resolution. I have been driving a 5500 for 2-3 years with Onyx and it is pretty quick and the quality is good.

Phil

[Hotspur]

Hi

Don't confuse the Onyx virtual dot or dpi resolution with the HP doublestrike. They are all different things.

You can tell the virtual dot resolutions as they have an "@" in the name. Its not a true resolution and multiplies data to add more dots alongside existing dots (increasing "apparent" resolution) without the RIP processing overhead. You find it on many Onyx printer drivers, not just HPs, and as only HPs use doublestrike in this sense, it is not the same thing. If you use virtual dots on the JV3 for example the second dot placement looks like a ghost image and makes the whole image appear blurred - avoid!

HP Doublestrike is the c1 and c2, m1 and m2 etc found in the advanced ink restrictions - c1 is one strike, c2 is the second strike - both dots this time placed in exactly the same place - HP doublestrike is thus used to add more ink in a particular spot, rather than put more dots down over a wider area as in the case for virtual dots. It is amount of ink we are concerned with, not apparent resolution. Note - you only get doublestrike with the "normal" CMYK inks - not on light inks.

Therefore, ignoring virtual dots for a moment, 1200x600 would be a valid resolution - higher than 600x600 dpi in the normal sense and niether has anything to do with doublestrike - you can have doublestrike with either resolution if available. Select your resolution in the mode settings and later on in the process, set your doublestrike according to the final ink restrictions you decide on.

To set ink restrictions on an HP using doublestrike you must set both strikes on normal "dark" CMYK to 100% (and set light inks to 0%) in the advanced tab.ie c1 100%, c2 100%, m1 100%, m2 100% y1 100% etc etc

Run the strip to show you what the media does with full doublestrike & when dry measure with the measure tool, using Lch and checking the graph for maximum colourant on cyan and magenta - you can use good old density to check yellow & black.

If you decide that Cyan needs a restriction of 60% then you are going to have to reduce either or both strikes down from 100% but how do you split it? you could give both c1 and c2 a restriction of 60%, which would thus be a combined total of 60% which is correct mathmatically but not the best choice. Better to give one strike a full dot (100%) and the other strike whatever you have left over - in this case 20%, This way you still have the same amount of ink going down (100%+20%=60% accross both) but gives you better coverage. For years I have set c1 to 100% and c2 whatever is left. Recently someone pointed out Onyx do it the other way - c2, m2 ,y2 & K2 always get the full dot and c1 etc gets the rest. I've done it both ways now and can't see a difference.

If you use the basic way of assessing ink restrictions you can't control doublestrike in this way.

Don't forget to set your light inks to 80% of your final figure. In this case you need to set them to 80% of 60% which is 48%, before moving on. Also, don't use the quick button which automatically sets the lights to a percentage of the darks in the advanced tab - the programming is screwed as it sets both the light inks and the first strike to 80% of the second strike - it seems to link these together rather than linking the two strikes together - whoops. Just work it out manually and set the light inks accordingly.

To make life more interesting, HP separates pass rate (print speed) from dpi (RIP resolution). On an Epson you can shoose a 720dpi setting and print at a certain speed. Then choose a 1440dpi and find your printer is running three times slower.

But with HP drivers your dpi setting is the speed v quality of the ripping, not the printing. A high dpi will give you a slower RIP time and higher quality result. A lower dpi will speed your ripping time up but give you a more grainy result. Neither will affect printing times greatly. This is controlled by your pass rate, the lower the number the faster the printer will print. Thats why the throughput is the same for you on different resolutions - your pass rate is the same for both.

Thus for good profiles you select the dpi you need when setting up your mode - 600dpi is often chosen (I avoid virtual dots!) and in the options use non-varware mode to allow you to select the pass rate you want. start with a high pass rate - 10 is often chosen. Then move downwards - try 8 and even 6. All the time the printer will speed up until banding is introduced. At this point stop and go back up the pass rate scale one notch - that is the fastest your printer will go with that media. most HP5000 / 5500 profiles have pass rates set too high and thus they run slower than is neccessary.

The varware mode "Max quality" etc are just presets of pass rate and a few other things rather than dpi - thus Max Quality would be 12 passes etc - better to be in full control and select them yourself. (HP tends to think we understand what Max Quality means and would get confused by numbers!)

If you can't see the resolution you want, it may be that it needs to be checked in the printer settings before you begin to profile (fourth button down in Media Manager Home page) I don't have a copy of Onyx with me right now to check if a 1200x600 resolution exists for this printer - sorry!

Hope some of this is useful - most of the above applies to HP Z series as well