Epson P7500 driver settings and print detail

What factors affect fine print detail [P7500/P7570]

Is there a ‘best’ print setting for printing? Are there better P7500 driver settings which make a difference?

During recent printer testing, Keith has looked at how much detail you need to send the printer driver for optimal printing and how this varies with different printers

There are lots of print quality settings in the driver for the Epson P7500 printer, there is often also the choice of how much image detail to send to the driver from the original image.

This has led to a lot of ‘web wisdom’ about optimal printer and driver settings for the best quality. As with much such ‘wisdom’ Keith has often wondered if it could be outdated and based on best practice from 15 or more years ago.

This article looks at some experiments carried out with an Epson P7500 printer (P7570 in the US) and using Epson’s Premium Luster paper.

There is much more discussion about what factors may be important in the original P700/900 printer detail article (and video)

A short video (9m) to go with this article.

P7500 driver settings and print detail – a balancing act

This is very much a qualitative experiment and evaluation. It’s not about providing detailed optimal settings or the ‘best’ settings. If you disagree with what I suggest, then fine, please go and do some experiments with your own printer – I’m really happy to discuss practical tests, less so theoretical opinions on what one ‘ought’ to do… ;-)

This is about making prints that look good…Ones you are happy with

If you want just a set of P7500 driver settings to use and not think about what you want and what is important in your images and printing, then you will be disappointed.  In fact I’m afraid you will be disappointed with a lot of my work, since I’ve long avoided specific step by step guides or recipes. There is no ‘best’ and there is no ‘correct’ answer in printmaking.

What am I looking at?

I’m curious about two aspects of printmaking in particular.  One is how high in the printer driver ‘quality’ settings do you need to go, and secondly, does sending more image resolution to the printer driver make for more detailed prints.

I’m testing this using the Epson P7500 printer. This is a large format 24″ pigment ink printer and I have reviews and lots more info about the printers in articles and videos.

• P7500 review

A photograph to test my P7500 driver settings

I’m using a photo I took up in the Yorkshire Dales with my 50MP Canon 5Ds.  The actual image is one I’ve comfortably printed at A2 size, so I know it has fine detail and represents aspects of what I’ll typically print.

The image has had a little sharpening applied, but that doesn’t really matter here, since I’m interested in how the printer driver translates pixels in the image into dots of ink on the page.

Sharpening is vital to the perception of sharpness in a print, and along with many other aspects of editing a RAW camera file image, is important in producing a print that you are happy with. There are lots of techniques for processing files for print and they generally only make much of a difference when the print size becomes larger.

I’ll come back to what I feel is important in prints later, but even at this stage I have to remind those of you itching to get the hand-lens out to check over prints, that real people don’t see most of what worries some photographers about fine print detail.

300/360 nozzles per inch?

With the Epson P700/ P900 and older Epson printers, the ‘native’ print resolution and settings are multiples of 360 pixels per inch. This number comes from the physical density of nozzles in the print head. Hence you get resolutions such as 360/720/1440/2880 appearing in settings.

The P7500 uses a new head design with a 300 nozzles per inch arrangement – this means numbers such as 300/600/1200. As an aside, this is the same as Canon (albeit with very different head technologies) – see my PRO-200 and PRO-300 print resolution articles (I used the same images for testing the P500 as I did the two Canon printers).

What’s so special about these numbers for driver settings and print detail?

Print resolutions and ‘magic numbers’

Two terms I’ll be using always deserve some clarification, since people often use them somewhat interchangeably, when they refer to different things.

Pixels per inch (ppi)

My image above is a grid of pixels of different colours.  These pixels have no inherent size until I decide to show the image at a particular size.

So, if one side of the image was 1000 pixels across and I printed it so that side was 10 inches long, then the resolution would be 100 pixels per inch (ppi). At 20 inches long this would give me (for the same 1000 pixels) a resolution of 50ppi (1000 divided by 20).

For comparison, the pixels on a typical display are 70-150ppi, but can be distinctly higher numbers on some phones.

Dots per inch (dpi)

When printing, each pixel of the image will be represented by a number of printed dots of ink. The colour/brightness of the pixel is represented by several dots of different colours.

Using the pixels example of 100 pixels per inch, each of those pixels needs to be represented by multiple ink drops. So, if each pixel were represented by a 5×5 grid of potential ink drops, I would have a dot resolution 5 times the pixel resolution of 100ppi, or 500 dots per inch (dpi)

Actual printing

Several features of modern printers contribute to the improvement in printer performance over the years.

• The number of inks has increased in many printers – a wider range of ink colours makes it easier to get the ink dots for a pixel to better represent its colour.
• The size of ink drops has decreased allowing more to be fitted close together (overlapping or not)
• Ink droplets may be produced at different sizes
• The software/firmware involved in converting pixels to ink drop positions has become much faster and more powerful, allowing more and more complex calculations to be carried out in the limited time available at normal print speeds.

One of the most under-appreciated aspects of inkjet printer functionality is the sheer amount of calculations required to control the inkjet printhead as it flies over the paper. Epson has quite a lot of web material covering their print head technologies if you are curious.

To print at a reasonable speed, each colour ink channel in the printhead has multiple nozzles firing out droplets. These are usually arranged in lines at right angles to the direction the print head moves.

The gap between the nozzles and the need for multiple passes of the head to build up a printed image gives a natural amount of movement if for example you wanted the droplets of one sweep of the printhead to match up with droplets from previous passes.

In The P7500 Epson printhead this produces a basic pattern at 300 per inch. In reality, the control of fine movement of the head and of the paper advance can give finer movements than this, but when you look at printer driver settings with resolution numbers in them, they often come in multiples of 300. So 600,1200, etc.

If I take an image at 300ppi then ink droplet calculations are a bit less complex than if the source image was at 307ppi.

It’s this limitation on complexity that helped push the idea that having your source image at a particular resolution produced better results when it came to reproducing detail in prints.

Twenty years ago, the dithering patterns (how the ink drops are distributed)  were simpler, they didn’t really look at adjacent pixels, and the maths for scaling and interpolation were simpler (for speed as much as anything).

As I’ve mentioned, the two areas I wanted to look at were whether sending extra detail (higher ppi) when printing made a difference, and whether the highest quality modes of the print driver made much difference, apart from taking longer to print. How much importance should you give to driver settings and print detail?

Making the prints

The image was resized in Photoshop to 1200, 600, 460 and 300ppi versions. These are the same size, but just with less resolution.

The 460ppi version is to give a feel as to whether changes from 300 to 600 are gradual or more of a step. If the differences suggest a more stepped response I might do some more versions, but that depends on what’s visible and how much difference I can actually see.  If sending more than 300ppi doesn’t make a difference then the prints from the different images will look similar – if that extra detail shows, then it does make a difference.

The files were printed directly at one of the 3 standard P7500 driver settings for quality, in the (Mac) driver – the names may differ in the windows version, but the variations should all be there.

Quality | High Quality | Max Quality

There are other driver options you could experiment with here, at the cost of making lots more prints. However previous experience has taught me that it’s the broad quality settings which make the difference

Here are the relative sizes of the images, when viewed at the same resolution.

As you can see, there is simply much more image information in the 1200ppi version.

Looking at the prints

The small images fit two to a sheet of A4 Epson Premium Luster.

I’m photographing parts of the prints at ~2x with my 50MP 5Ds and the Canon MP-E65 macro lens I use for much of my commercial macro work (mostly electronic components).

This is higher resolution than the 1:1 I used in other tests – it does make the individual ink drops on the paper a bit clearer than the other tests – I mention this should you wish to make comparisons

The ruler and lens cap are just weights to keep the print flat.

Here’s the full set of pictures, at different P7500 driver settings, from when I was processing the RAW camera files

Click the image to enlarge

The rows are at the three quality settings (Q/HQ/Max)

The columns are at the four image resolution settings

Here’s the part of the original full resolution image at 100%

The actual ppi for this image depends on your monitor and just how you are viewing this article.

As ever, put this small bit of the whole image in context before you think it looks a bit lacking in detail…

Looking at the dots – driver settings and print detail

This section is just lots of images from the photos. The images can be double clicked and opened in a new window to see in more detail – just remember how small the areas you are seeing are on the actual prints.

BTW – try squinting a bit to blur the dots? It can help reveal more image detail.

Image at 300 ppi

At the three quality settings

Quality

Hi Quality

Max quality

Image at 600 ppi

Now with the same source image but at 600 ppi of source resolution.

Quality

Hi Quality

Max quality

Note how the vertical post in front of the dry-stone wall is now just about showing up at the highest/max quality setting

Time for a look at quality vs resolution

High quality at different resolutions

Four shots at resolutions from 300 to 1200 ppi – all printed at the ‘high quality’ setting.

These are reduced in size to make changes in detail a bit easier to see

300ppi

460ppi

600ppi

1200 ppi

I don’t see any benefits going over 600ppi sent to the printer driver. Indeed, looking at some of the images in more detail suggests that sending more than 600ppi has a detrimental effect.

However there is a difference from 300->460->600 which suggests that if you have a big high resolution image, then sending it at higher than 300ppi can give a slightly better looking image.

Have I learned much about P7500 driver settings and detail?

Well, two things stand out – if for some reason you need really fine detail, the P900 will give you a finer detail print than the P7500. That’s not very surprising given the larger droplets, and massively bigger print-head the P7500 has. You have more inks and much faster printing on the P7500, so it’s a very tiny victory to the P700/900

Secondly, the high quality and max quality settings are very similar in terms of detail, but the max quality setting has a smoother look. Both are better than the basic ‘quality’ setting – something just for when you’ve a lot of prints to do and you’re in a hurry…

OK, what practical use will I make of these tests?

For photo papers I can just about see a little coarseness in the prints at the quality setting.

In context, I need to have my strongest reading glasses on to see this and I’m looking at the prints from close-up. Not so bad for 5″ x 7″ prints, but for myself, pretty unlikely for prints at A3+ size (13″ x 19″) or larger, as you’re likely to be using if you get a P7500 or the larger P9500

In terms of image resolution I’d use as high a resolution as I had available up to 600ppi – this would be especially so for my architectural work, where fine sets of lines are a more common feature than my landscape shots.

Some context – what matters?

OK, so for my own work, printed on a P7500 I’m seeing no real detail benefits of the very highest settings. For the P7500 there are benefits visible (just) on some papers when using the max quality [carbon] setting in that blacks can be a bit deeper.

Compared to the P700/P900 I’m seeing less obvious differences – enough to say that were I regularly using a P7500, I’d likely do some more tests like this on any paper I was using very often to find a useful setting.

However, there is much more about making a good print than poring over detail so fine that no-one is ever going to see it ;-)

In general I prefer to include ‘better’ quality option in my workflow, such as working at 16 bit, in the feeling that sometimes small improvements can add up to what becomes a ‘better’ end result. This is very difficult (and boring) to test in a meaningful way.

This is where stepping back a bit can literally give a different view.

What was distinctly noticeable when testing the P700/900 was that for the Epson Premium Luster paper I could detect some bronzing at the two highest settings – this confirmed my testing for B&W printing with the P700 and P900

The P7500 ink set shows much less of this effect, so I would be inclined to consider the highest quality settings, where I might not for the same paper on the P700/900

Above all, this testing reminds me that you need to test and measure things and not just rely on what you feel ought to be the answers…

What about YOUR printer/paper?

If in reading this you are still inclined to use highest quality settings ‘just in case’ I’d suggest you do a few small prints of a highly detailed image and actually look to see if the differences matter to you. Above all, be honest to yourself…

Don’t be unduly swayed by ‘forum experts’ and anyone who starts introducing any maths into their argument (if not backed up with actual meaningful examples). Watch out too for people extolling the virtues of any particular bit of printer driver software – demand real examples showing the benefits. Chances are they will not have carried out any real testing – not even at the cursory level I have in this article. Even if they have – is it actually relevant?

Above all – test things and learn trust your own judgment ;-)