Are PDFs on e-readers really that bad?

[JawadLeLogeur]

After seeing this repeated several times it seems abundantly clear that tablets are a better choice for PDFs.

However, KOreader seems like an impressive piece of software and the e-ink screen makes an enormous difference. Therefore, I want to find out in more detail exactly how painful it is for the user to go through PDFs on e-readers, so that I can decide whether the trade-off is worth it according to my personal preferences. I'd say I'm willing to tolerate some discomfort if I can have the paper-like screen.

Unfortunately, I can't really gamble money on an e-reader and test it out myself because my budget is really limited, especially since the models with the larger screens are quite expensive.

If you could tell me more about your personal experiences with PDFs on any e-reader using KOreader, I would be very grateful!

[Ken Maltby]

PDFs vary greatly. Most are not meant as e-books, they are documents, pamphlets, brochures, manuals and for lazy academics, essays. They are made to be printed, not published. Many are just scanned pages, images. (In other words; they can often contain no words, just the image of a page of words.) KOReader's PDF reading program includes an OCR function that can detect the words on an image of a page and "reflow" them into something that can fit on your device's screen. Of course that is never going to look as good as the page displayed as a full screen image. KOReader includes some good auto cropping tools so you can often have quite readable PDF pages displayed, without reflow, on the larger devices. I find no problem reading US Army Field Manuals (FM) on my AuraHD.

Luck;
Ken

[Alan_S]

Also, with koreader you have option to manually crop pdf document.

All in all, koreader is the best you can have for reading pdfs. But, it is most important thing to know, pdfs aren't good format for ebooks. There always will be some problems with them compared to "real" ebook formats.

On the other hand, if you have large screen with high resolutions (let's say KA1) and have koreader, you can have pretty comfortable experience with pdfs. And KA1 isn't that expensive (I must say, this is actually relative thing, how much money is too much).

[JawadLeLogeur]

Thanks for your replies! You've convinced me to try out the Aura One and install KOReader on it

[compurandom]

Most PDF's are designed to be printed on 8.5"x11" paper.
The closer your e-screen is to that size, the easier the PDF will be to read.

Features like autocrop let you remove all the blank space around the edge of the page so that what is left can be expanded, hopefully closer to its original intended size without actually getting a bigger screen.

OCR and text reflow can be wonderful if they work, but they don't help at all when my page is one big diagram with embedded text, and are easily confused by multi-column text, especially when there are images and other irregularities between columns.

[HarryT]

I'm very much in the "PDFs are better on tablets" camp, I'm afraid. I read a lot of material in PDF format, and many years of doing so has convinced me that a large-screen tablet - the larger the better - is the best way to read such material. Not only do the file sizes tend to be large (I have many files that are >100MB, which doesn't go very far on an eInk device with 4GB or so of storage) but displaying them can be CPU-intensive and RAM-intensive. eInk devices generally have slow CPUs (to maximize battery life) and not very much RAM.

After years of trying to find the optimal device to read PDFs on, for me it's the 12.9" iPad Pro. Fast CPU, lots of RAM, great screen, and lots of storage space (I have the 256GB model).

If you go decide to go for an eInk device, I'd strongly suggest choosing one with at least a 9.7" screen, and much better a 13.3" screen.

[compurandom]

Originally Posted by HarryT

I'm very much in the "PDFs are better on tablets" camp, I'm afraid.

If by tablet, you mean a device that can do smooth variable panning and zooming, then I fully agree with you. Your comments about cpu speed and memory are spot on as well.

Having said that, the vast majority of PDFs work just fine by either zooming 2x or rotating 90 and matching autocropped width to the long axis of a screen that is at least 5" and then panning vertically down the page.

Maybe one pdf in 20 is a high resolution scan that needs a lot of ram or complex drawings that need a lot of cpu to render.

Maybe one pdf in 40 has stupid colors and low contrast that render poorly in 16 shades of grey. I've seen a few scanned documents with non-white background or some kind of watermark that renders stupidly on the e-paper screen.

Maybe one pdf in 15 has fine print that I just can't seem to zoom enough, or worse, when I have zoomed it enough, I now have to pan horizontally several times to read the whole line -- this makes it very unpleasant to read.

About one pdf in 5 is multicolumn text which is nice because if I can pick the right zoom, I can see the whole column width without rotating, so maybe I can vertically pan once or twice per column.

Of course, your experience may vary because if you are getting all your pdfs from a single source or similar sources, they might all have one of these problems that just work better on a tablet with more memory, a fast cpu, and/or a color screen.

There's no replacement for a larger screen, but I think 4" x 6" (7") is probably adequate for 90% of pdfs. 6.5" diagonal is marginally adequate. Much larger than that is nice, but probably overkill.

If you go decide to go for an eInk device, I'd strongly suggest choosing one with at least a 9.7" screen, and much better a 13.3" screen.

I think 9" is overkill for sure (but like I said, it would be nice). 13" would let you view documents at their intended size without cropping off the white space around the edges or zooming and panning at all. Very few documents need this, but if you got a pack of architectural drawings or something, even this screen size might seem small.

[Frenzie]

I agree with HarryT that in principle, a decent monitor (like my 24" UHD monitor or a larger tablet with 300 PPI or better) makes for a much better random PDF experience, but it all depends on your goals. I read many PDFs on my H2O. I find screens without backlight make for a significantly better reading experience. I sacrifice the usually unnecessary minor convenience of smooth scrolling and zooming for viewing comfort and not having to worry about battery life.

Besides which, I think it's much harder to justify spending money a tablet because you need a decent monitor regardless. That's different if you need it for a job, like the architectural drawings mentioned by HarryT. I'm operating on the assumption that it's basically a luxury item to make it slightly more convenient than on the desktop or laptop that you already need.

I think that regardless of what device you use, many PDFs are greatly improved by some form of processing (see, e.g., the readablepdf script I wrote). When I perform such processing, I actually do it primarily for desktop use. However, the greatest improvement can actually be felt on ereaders with weak CPUs.

Originally Posted by HarryT

If you go decide to go for an eInk device, I'd strongly suggest choosing one with at least a 9.7" screen, and much better a 13.3" screen.

However, on this one I beg to differ. If the actual resolution of the screen is smaller than on my H2O then you won't win any legibility.

Also, this book (just as a random example) is bigger than A4 in real life but perfectly legible on the H2O. If you think it's a tad small you can always use landscape mode.

[JawadLeLogeur]

This is great additional info, thanks!

[HarryT]

Originally Posted by Frenzie

I agree with HarryT that in principle, a decent monitor (like my 24" UHD monitor or a larger tablet with 300 PPI or better) makes for a much better random PDF experience, but it all depends on your goals. I read many PDFs on my H2O. I find screens without backlight make for a significantly better reading experience. I sacrifice the usually unnecessary minor convenience of smooth scrolling and zooming for viewing comfort and not having to worry about battery life.

That's where we differ. I consider smooth scrolling and smoothing to be essential, rather than a minor convenience .

Besides which, I think it's much harder to justify spending money a tablet because you need a decent monitor regardless. That's different if you need it for a job, like the architectural drawings mentioned by HarryT. I'm operating on the assumption that it's basically a luxury item to make it slightly more convenient than on the desktop or laptop that you already need.

Sure, I agree that it is a luxury item. I'm a well-paid job and I can afford life's little luxuries like a large-screen iPad. If I were a penniless student, I certainly wouldn't be able to. Not me that mentioned architectural drawings, by the way. I use my iPad to read Egyptology books and journal articles.

However, on this one I beg to differ. If the actual resolution of the screen is smaller than on my H2O then you won't win any legibility.

You won't gain any detail, but as you get older, you start to need larger screens to be able to read comfortably. 30 years ago I was happily reading books on a Palm device; now I need a larger screen to be able to see the same thing. A 9.7" screen is about the same screen size as a typical hardback book, so for me it's ideal for reading page-scanned PDFs. Fiction I happily read on my Kindle eInk reader.

[Frenzie]

Originally Posted by HarryT

That's where we differ. I consider smooth scrolling and smoothing to be essential, rather than a minor convenience .

KOReader generally automatically zooms and crops in the most optimal fashion, hence making that unnecessary. When it doesn't, it's still very easy to crop manually. I find this much more useful overall than zooming and panning more smoothly, especially when it's once versus every page. Incidentally, KOReader scrolls fairly smoothly, see here. In practice you normally just don't scroll though, because there's simply no point to it. You can also see how it autocrops that particular document perfectly, which is par for the course in the documents I read.

On my desktop I can easily affect similar cropping, but on a tablet or phone type OS it's all very limited at worst and very difficult at best. Additionally, the lack of page down on my phone and having to scroll by necessity rather annoys me. Bubble is pretty much the only app I actually appreciate because of the intelligent way it zooms and deals with pages.

Sure, I agree that it is a luxury item. I'm a well-paid job and I can afford life's little luxuries like a large-screen iPad. If I were a penniless student, I certainly wouldn't be able to. Not me that mentioned architectural drawings, by the way. I use my iPad to read Egyptology books and journal articles.

My point is primarily that, at least for me, a tablet is a redundant, inferior version of stuff I already otherwise already own (and need!) for other things. An E Ink device is not redundant because it brings a different type of technology to the table even if it is more limited in many ways. Of course that's entirely the manufacturer's choice. You can clearly see that in principle the display is capable of much more. See, e.g., games on a Nook from 5+ years ago and another Nook. Clearly the rest of the hardware is a much more limiting factor than the E Ink display technology.

If I felt wasteful I'd get a tablet as well, but only one that clearly offered me something extra, like being able to draw on it properly. As it is I already have that from my regular, much cheaper Wacom tablet that's "only" good as a computer input device. (Although for all I know it can be used on Android and iPad with Bluetooth or something, but that aside. :P)

A 9.7" screen is about the same screen size as a typical hardback book, so for me it's ideal for reading page-scanned PDFs.

A 10" E Ink device would be great, but for me the existing ones that I've seen (and that are affordable) are pretty useless resolution-wise. Although I don't like iPads much in general, I'd definitely much rather get an iPad Pro or some such, in spite of the backlit screen, which has a roughly comparable PPI to my H2O.

[pickyaxe]

Frenzie, after reading your interesting take on reading PDFs on eInk (which I agree with, also reading plenty of PDFs myself) - if you don't mind, what is your opinion of the Aura One? Do you think it's an improvement over the H2O?

[emacsomancer]

For me, I already have some nice large computer monitors, and a nice laptop, so if I want to read on a phosphorescing screen, I'm covered. No interest in an iPad, and I already have a 10.1" IPS Android tablet for an even more portable eyeball-electroluminescing experience. But what I really want is an experience more like reading on paper.

Just acquired a Kobo Aura HD for $80 - it's at least largish (6.8") and has a microsd card slot so I can carry 32Gb of pdfs. I've been reading pdf books and scientific papers on it and it's not a bad experience at all.

(I don't get the recommendations for non-eink tablets [I've just had one on my 'welcome thread' too; now closed, so I can't reply.

I've spent the last four years trying to use a non-eink tablet for pdf consumption and it's not a pleasant experience for me at all, and so I just don't end up using it.)

[emacsomancer]

Originally Posted by pickyaxe

Frenzie, after reading your interesting take on reading PDFs on eInk (which I agree with, also reading plenty of PDFs myself) - if you don't mind, what is your opinion of the Aura One? Do you think it's an improvement over the H2O?

One thing to keep in mind is that the Aura One has no microsd card slot, so you'll be limited to the 8Gb of internal storage, unlike with a Aura HD or Aura H2O. This meant that I wasn't interested in it; sure that's plenty of space for lots of epubs, but not so much for scanned pdfs.

[Frenzie]

Originally Posted by pickyaxe

Frenzie, after reading your interesting take on reading PDFs on eInk (which I agree with, also reading plenty of PDFs myself) - if you don't mind, what is your opinion of the Aura One? Do you think it's an improvement over the H2O?

I'm confident that for me it would be, although I should caveat that by saying that I've never seen it in person. What I remember from the specs (without double-checking) is that it's basically an H2O. It has the same specs in CPU and RAM in performance if not literally. (Incidentally, wasn't the Aura HD also already basically the same?) Obviously I'd like to see it somewhat faster, considering my old 2011 lower-end smartphone already was quite a bit faster than that 2014 device ffs, but since the screen only has a few more pixels performance shouldn't be noticably worse. It also weighs the same (233 g vs. 230 g).

The differences consist of a slightly bigger screen, a slightly higher PPI, and no a µSD slot. I consider the screen size and to a lesser extent DPI the most important shortcomings and highly welcome improvements. However, the differences are too small to justify the price of upgrading. I guess I could consider selling off my H2O.

I've really only ever put in a µSD for testing. Having a few dozen books at once (including some that are pretty big) is plenty for me and anything more would just give me the convenience of never having to delete anything.

PS I suppose there's one thing I'd need to see it in person for: to make sure the frontlight can also go as low in brightness as the H2O. I normally don't use it at all, but in the rare case I do I put it at 1 or close to it. I might appreciate a warmer light temperature but really frontlight doesn't matter to me at all as I don't use it.

Originally Posted by emacsomancer

(I don't get the recommendations for non-eink tablets [I've just had one on my 'welcome thread' too; now closed, so I can't reply.

I've spent the last four years trying to use a non-eink tablet for pdf consumption and it's not a pleasant experience for me at all, and so I just don't end up using it.)

That's something everyone can make out for themselves. I sometimes read comics on my phone and on my laptop, where I appreciate my laptop's ability (ASUS Zenbook UX305C) to put the backlight really, really low. It's as good or better than the laptop I had back in '04 whereas everything since has only been able to go way too bright as a minimum. Anyway, provided minimum brightness isn't way too bright and PPI isn't horribly insufficient I think screens that shine at you can be reasonable. A larger version of my phone (5.5", ~300 PPI) would be an acceptable comic and newsfeed reading experience for me.