Balling

There's a heap of issues in that article. I'm unsure if the author is explaining themselves poorly or just not entirely strong on the subject, but I honestly wouldn't recommend taking anything on that page as fact.

No sarcasm, if you've genuinely dealt with a majority of all the print suppliers around the world, then I retract any comments I've made as you clearly have more experience in the field than I have in my 12 or so years of working in print production. If, on the other hand, as I find more likely, you've merely dealt locally, then you'd probably agree that, in the bigger picture, your experience is somewhat limited. Also, and again I'm really not trying to insult or be rude, just pointing out the facts, you've made it clear that you didn't have the full grasp of this subject, given some of your comments, so isn't it likely that you have heard "DPI" whenever someone has said "PPI"? Not being a software engineer I certainly have a hard time following all the acronyms used in programming and easily get things mixed up, so as I said, I don't think anybody expects of you to be the foremost expert on the subject. There's no shame in that. And all that aside, as I've said before, why is your goal not to use the most correct terminology in stead of pandering to a, perhaps, majority of users who get it wrong? And again, for the third time I think, why is it that you think PPI will confuse people, when it's first of all the correct term and secondly what Adobe, the market leader, use in their UI? Chances are that a lot of your users are familiar with Adobe software, so using a different (and wrong) terminology to them really seems silly.

Genuinely sorry about that, if that's the case.

I think that's a bit unfair and slightly besides the point. Everybody starts somewhere and learning about image and printer resolution is part of the learning curve for many roles in the industry. If you have to start by unlearning old knowledge, then it gets even more difficult to acquire knew knowledge. I think this is definitely something everybody can learn and while I know it can easily be perceived as being pedantic (and probably is) I honestly feel like we have an obligation to guard our profession by being exact in our terminology. As for the metadata discussion above, I'm glad Mike stepped up as I honestly know very little about how EXIF is actually stored, read and written. :huh:

Oh, and regarding the slightly odd "it is just a number" comment, try looking at it this way. Say you receive an image that needs to be placed in a layout. The image is 3780 x 1890 px and you want to scale it to 400 x 200 mm. This leaves the image at 240 PPI. Now, you can't change any of these numbers. The size is set and so are the pixel dimension of the image (bar interpolation, but let's ignore that for now). Hence the PPI is set as well. All of these values are out of your control at this point. However, the DPI you do have control over and it does affect image quality. You can now choose to print your image at whatever DPI settings your printer (or supplier) allows. It won't change the image, it won't change the size, yet it will change the quality. Do you honestly not think this distinction is important? I've seen SO many people who honestly think they have to make a 540 PPI image to print at 540 DPI resolution and are completely confused why this isn't the case. Understandably so, I might add, given that the people they talk to and perhaps even the software they use confuse the terms. I'm curious if this makes sense? Maybe I'm explaining myself poorly. It's worth adding this is a second language to me, so there might be a barrier there, I don't know...

What a weird experience this is. Here I am, pointing at something that's clearly, no doubt about it, an error in your software (and I'm not the first to point this out, I might add), yet you guys are trying to alternately downplay it as insignificant or downright defend it as not being an error. So far, your only arguments have been to point at other software and people making the same mistake. That's the only argument I've seen. I'm curious if you've even read the explanations I've given and the links I've provided? Do you have any comments on the many quotes where your team is making it clear they don't understand this? That's really what I don't get. You, yourself, is a software engineer. I don't think anybody expects of you to know this subject (I mean that as in "it's not your field" not in any way that would imply prejudice against software engineers), yet you seem hell bent on defending a decision that was clearly made from an unenlightened point of view. Now that you're enlightened, you seem like it would be a personal defeat to admit the mistake. You might think this subject is unimportant to your user base, yet the people pointing this out are inherently your users. I honestly thought you guys wanted every little detail to be perfect, which I'll admit was completely my own mistake.

I think calling that an error is a bit of a stretch. Showing the display configuration would confuse the point. Remember, not all displays (though the vast majority) have a traditional RGB configuration (opposed to PenTile or RGBw), so currently the diagrams on the page are correct, regardless of display type.

"we weren't going to change it right now" If you have plans to change it, and hence now it to be wrong, why didn't you just lead with that? Just by using the word "technically" in this case, you're painting the thing in shades of grey. They're different. Not somewhat different, a little different or sort of the same. The terms are completely, flat out different. And certainly, as you request, here are some quotes from Serif staff being wrong about this subject. "there is a widespread acceptance of the term DPI as being understood to mean PPI" Nope. Not true. Certainly in your office there is, but in the world of professional print production? No. "Regardless of what you think those terms meant in the past" The meaning never changed. "there is a reasonable correlation between DPI and PPI. It's largely assumed that these can be used interchangeably" That's a silly assumption. It's also wrong. "We use DPI because we don't know if you're going to print the document or export it as an image. If you print, then DPI = DPI, if you export, then DPI = PPI. Hence why we said the terms are used interchangeably across most software packages." That makes no sense. "It may take some time to convince Microsoft to change their Explorer File > Properties > Details from displaying Horizontal and Vertical resolution in DPI, it may even be futile." Well isn't that a shallow argument? "we have deliberately used DPI and it is not an error" Well sure it's an error, you just don't know it. "It would need to change to say DPI/PPI each time the units changed between screen or physical types" What? No, that's not at all how it works. It's always PPI. Your software doesn't need a DPI setting, ever. "and what if you are creating a document for print that is not measured in pixels" I don't even know what point this is supposed to make. So there, I trawled through you guys not understanding the subject, now please, honestly, take the time to read up on this (I provided two useful links in my second post). I assure you, as soon as you do, you'll see why the distinction is important.

@Mike "I think that by injecting large format work (i.e., the viewable distance resolution info) it is not helping your case." Could you elaborate? Small format printer and big format printers alike use DPI. "how they are using it is perfectly understandable" I've never questioned that. I knew straight away that what they meant was PPI, hence making this post. It should honestly be very clear from this and the other forum posts that a lot of people who use (or make) graphics software don't fully understand this subject. Using the right terms in software would greatly help in this regard. "I think there are far larger fishes to fry as regards AD" Can't comment on that and I wasn't trying to imply that this is the biggest error in the software. Just that it's an error. I'm completely fine with Serif deciding this is not something they want to fix, that it's an error they don't mind in their software. I'm also fine with them giving it a low priority, that's not my business and I've no clue how difficult a task it is to replace a single letter however many places in the UI (not very, is my guess). I'm a bit confused though, by their apparent attempt to claim that this is in fact not an error and not the wrong term. "If Serif (and other software makers) changed the terminology regards PPI versus DPI. they would generate a lot of support questions" So you're argument is literally that people are so confused by this that using the correct terms would raise support questions? That's a bit silly. And I honestly don't think Adobe, who use PPI in all their software, are flooded with questions from people who don't get this. Btw, Adobe used to have this exact error in their software 10-15 years ago, but they admitted it was an error and fixed it.

Not really, no. Here's what he said about DPI. "DPI (Dot per inch ) is for print. Think of half-tone patterns, that is how a print "prints"." Yes, printers use Dots Per Inch to print. Agree so far. "if you are working on CMYK document that needs to printed. Use DPI." No, you don't use either DPI or PPI. If you're printing images, you inherently use both. It's not a choice. Whether it's CMYK or not has nothing at all to do with it. Nada. "The print shop you use will almost always provide [...] a min and max DPI..." They might provide that, but they'd be bad at their job in that case. A qualified printshop will ask you what DPI you wish your prints printed at. At a given DPI and a given viewing distance (vd) a certain PPI will be sufficient for your job. This is common math that makes no sense if you incorrectly use DPI for both values. Seriously, there's no argument here. You're using the wrong term. I feel like I'm missing something here. Is there a bigger reason why you won't change this? It's not like I'm saying the software is terrible, so you don't have to admit defeat. There's an error, that's all. It's a common error, sure, but an error none the less. Patrick linked to several threads where users have pointed out this error and in each thread there's staff members weakly defending the "choice" to use DPI by pointing at other software that does the same and arguing that "they're largely the same". I've explained why they're not largely the same and even linked to articles describing the differences and why it's important to know and understand these differences. It's obviously not important to a software engineer, UI designer or hobby photographer, but it's certainly important for people producing files for print production, which is a segment I, perhaps wrongly, had the impression you were aiming for as well.

@Brian While you're right that designers perhaps don't need to worry about DPI, it's still a term they're likely to be confronted with when dealing with a printer or scanner or when communicating with a print shop. As per my example above, it's going to be near on impossible to understand why a print shop would offer you a 720 or 1080 DPI output, when you produced your file at say 240 DPI. If your software had correctly stated PPI, it'd be easier to grasp that you were dealing with two very different values. The scanner is another good example, actually. Say you scan something at 2000 DPI and then open the scan in Affinity and it's only 300 DPI. You'd think the scanner was broken. If Affinity said 300 PPI, again it'd help you grasp you were dealing with different things. I'm sorry that the print shops you've worked with haven't had a more professional approach. It's paramount to us to make sure that our clients get exactly the quality they need, but don't pay for a quality that's excessive to their needs. To hit this sweet spot we have a lot of talks with designers and photographers about, among many things, DPI and PPI as we want to make sure they know exactly what product they're buying and why it's the right choice for them. Currently we're in the process of making a physical "viewing distance" diagram with the same photo printed in, on one axis, different PPI and at, on the other axis, different DPI. This will help people understand how much you can get away with at even relatively small distances. A photo in 40 PPI can be indistinguishable from one in 300 PPI when printed at 540 DPI and viewed at a couple of meters distance. By the way, PPI only affects raster while DPI affects both raster and vector (as the vector is rasterised when printed). Another significant difference, that people are confused about when they think DPI has something to with image resolution only (and sometimes even image quality, as someone incorrectly stated above - a terrible quality image can still have a high PPI). I think this debate ultimately comes down to the philosophy of the people making the software, really. Do they want it to be "close to the mark" or flat out correct? I honestly only made this topic because I had the impression that the people behind the Affinity software were the sort of pedantic nerds, like me, that wanted everything to be spot on. Doing a search/replace for DPI/PPI seems a tiny job to solve and error that, as Patrick pointed out, a lot of people have noticed. After downloading the Affinity Designer trial to see if it's a piece of software that could have a home in a professional print production, the mistakenly used DPI where they clearly meant PPI was literally my first impression. That just seems a shame.

@Ben I'm sorry, genuinely not trying to be a nusance, but if you make graphics design software you REALLY need to read up on this. What CSJ is saying is just utter nonsense. There's simply no correlation AT ALL between image resolution, printer resolution and colour space. If you think DPI and PPI have something to do with CMYK and RGB, then you're getting a lot of things mixed up. They completely unrelated. Just like DPI and PPI. And "PPI is the opposite of DPI", what? And you're "going to have to agree with this"? Start here: http://www.andrewdaceyphotography.com/articles/dpi/ And here: https://99designs.dk/blog/tips/ppi-vs-dpi-whats-the-difference/ Like I said there is a widespread misunderstanding, which means that, as you say, even professionals and print shops mix things up. First of all, there's no two ways around this. Either you want to have the correct term in your software (like Adobe has) or you don't, that's completely up to you. Second of all, let me try to explain why I think it's important that you use the correct terms. In our print shop we have inkjet printers capable of outputting print at 360 to 1080 DPI. This is pretty standard. When presented with this fact MANY (especially young) designers are thoroughly confused as they have the notion that DPI is something they control in their software and that they somehow have to "match" our printers DPI setting. A finished printed image will always have both a PPI and DPI resolution. I can print a 100 PPI image @ 1080 DPI and a 300 PPI image @ 540 DPI. Printing a 300 PPI image @ 540 DPI would make very little sense, something you'll see right away if you understand that (and indeed how) the two are different. Printing a 300 DPI image @ 540 DPI on the other hand... Well that just makes zero sense to anyone. How could a print ever be both 300 DPI and 540 DPI? This gets REALLY confusing if software (and indeed the people who make it) use the wrong terms. Again, I realise I sound like a dick (which I guess is par for the course given your ironic "anyone who really understands this" comment), but I'm 100% certain that if you read up on these subjects, you'll see straight away that you can't just decide to use DPI in stead of PPI.

@peterdanckwerts Of course, you're right. @Patrick Connor Thanks for your reply. "...there is a widespread acceptance..." There is? Certainly not among professionals there isn't. I'd say there's a widespread misconception and misunderstanding only made worse by software confusing the terms. You're using the wrong term, there's no way around that. @csj I'm sorry, but everything you're saying is just completely wrong. Case in point that people don't understand these terms.

When you import a PDF in Designer it brings up the "PDF Options" window, which has a DPI dropdown (which I'm slightly confused by the purpose of). Per definition you can't adjust DPI (Drops Per Inch) on a file (drops of what?) so what you mean is probably PPI (Pixels Per Inch) which image resolution is measured in. The relationship between PPI and DPI is source for confusion for a lot of designers, so IMO it's paramount that the software we use gets it right. :)