Register Guidelines E-Books Search Today's Posts Mark Forums Read

Go Back   MobileRead Forums > E-Book Readers > Sony Reader

Notices

Reply
 
Thread Tools Search this Thread
Old 12-23-2010, 07:13 PM   #1
lustyd
Enthusiast
lustyd began at the beginning.
 
Posts: 40
Karma: 10
Join Date: Jan 2010
Device: Sony PRS-505, PRS-350, PRS-650
Screen Resolution

Hi all, I have a PRS350 and a PRS650. These apparently have the same screen resolution, and seem to run the same software. If this was the case it would be reasonable to expect the zoom levels to show the same text on the same page. For some reason the 350 shows seveal lines fewer than the 650 at the same zoom and page settings.
Am I going mad or are they actually different?
lustyd is offline   Reply With Quote
Old 12-23-2010, 07:27 PM   #2
wallcraft
reader
wallcraft ought to be getting tired of karma fortunes by now.wallcraft ought to be getting tired of karma fortunes by now.wallcraft ought to be getting tired of karma fortunes by now.wallcraft ought to be getting tired of karma fortunes by now.wallcraft ought to be getting tired of karma fortunes by now.wallcraft ought to be getting tired of karma fortunes by now.wallcraft ought to be getting tired of karma fortunes by now.wallcraft ought to be getting tired of karma fortunes by now.wallcraft ought to be getting tired of karma fortunes by now.wallcraft ought to be getting tired of karma fortunes by now.wallcraft ought to be getting tired of karma fortunes by now.
 
wallcraft's Avatar
 
Posts: 6,979
Karma: 5183568
Join Date: Mar 2006
Location: Mississippi, USA
Device: Kindle 3 and Fire
Yes, they have the same resolution in pixels and yes there are fewer words per line.

There are two approaches to character size: pixels and inches (or points, which are usually 72 per inch). If the size was in pixels, the 350 would have smaller characters but the same number of words per line. The character size is actually in inches, so the 350 has more pixels and the same physical size per character - and therefore fewer words per line.

The Hanlin V5 (vs V3), for example, uses the pixels approach, which is probably easier from a software point of view.
wallcraft is offline   Reply With Quote
 
Advertisement
Old 12-23-2010, 07:32 PM   #3
lustyd
Enthusiast
lustyd began at the beginning.
 
Posts: 40
Karma: 10
Join Date: Jan 2010
Device: Sony PRS-505, PRS-350, PRS-650
Quote:
Originally Posted by wallcraft View Post
Yes, they have the same resolution in pixels and yes there are fewer words per line.

There are two approaches to character size: pixels and inches (or points, which are usually 72 per inch). If the size was in pixels, the 350 would have smaller characters but the same number of words per line. The character size is actually in inches, so the 350 has more pixels and the same physical size per character - and therefore fewer words per line.

The Hanlin V5 (vs V3), for example, uses the pixels approach, which is probably easier from a software point of view.
Thanks wallcraft that makes sense, although I can't help but feel sorry for the developers! it hadn't occured to me that 12 point was a physical size rather than relative, I guess because Windows ignores the size of pixels
lustyd is offline   Reply With Quote
Old 12-24-2010, 05:31 PM   #4
jswinden
Astrophotographer
jswinden ought to be getting tired of karma fortunes by now.jswinden ought to be getting tired of karma fortunes by now.jswinden ought to be getting tired of karma fortunes by now.jswinden ought to be getting tired of karma fortunes by now.jswinden ought to be getting tired of karma fortunes by now.jswinden ought to be getting tired of karma fortunes by now.jswinden ought to be getting tired of karma fortunes by now.jswinden ought to be getting tired of karma fortunes by now.jswinden ought to be getting tired of karma fortunes by now.jswinden ought to be getting tired of karma fortunes by now.jswinden ought to be getting tired of karma fortunes by now.
 
jswinden's Avatar
 
Posts: 5,497
Karma: 6981326
Join Date: Sep 2006
Location: USA
Device: iPad Mini 2, iPhone 5, Nexus 7.2
It gets rather interesting when you see all the ways in which HTML stylesheets can assign text sizes. Here are three:

Pixels:

Probably the most common sizing used among those who design web pages. Each device has a certain number of pixels per inch when it comes to CRT and LCD screens. EInk screens also specify a number of pixels per inch but eInk screens display text differently than a traditional LCD screen. The 350 has appx. 200 pixels per inch of screen both horizontally and vertically. So if you specified a font size that actually stands 20 pixels tall, the text would be 20/200 inches tall or 0.1 inches tall. A PC LCD monitor might have 96 pixels per inch, so the same 20 pixel tall text would stand 20/96 inches or 0.21 inches tall. So pixels can be of different sizes for different screens.

Points:

Probably the most common sizing used in the printing industry where printed books, brochures, etc. are produced. I think points are frequently considered to be 1/72nd of an inch or 72 points per inch. Using points the printing document designers could estimate rather accurately how much text would fit on a printed page. Although I don't recommend using points for eBook stylesheets, a lot of printing based publishers do because that is what they are used to.

EMs:

Instead of using a size per inch, EM is relative. In HTML if you set the standard text size to some amount, then EM represents a size in relation to the standard text size. Setting a size of 1.5em is the same as setting the text size to be 1.5 times (150%) bigger than the standard text size. For example, if you set the standard text size for your document to be 16px, then assigning a value 1.5em to a heading level 1 (H1 tag) will increase the text size for H1s to 24px. In theory, if you do not define the standard text size for a document, the device on which it is displayed will choose one that is optimum for that device. Thus using EMs to define all the headings and non-standard text sizes would make them relative/proportional to the device optimum. In reality that might not actually work out as well as you would like.

Bottomline:

HTML and eBooks are much like the "Life is like a box of chocolates" quote from Forrest Gump, you never know what you will encounter in the stylesheet. I've seen all three used within the same ePub! I personally prefer pixels because I used them so much with HTML in the years gone by. But to be honest, for ebook EMs is probably the more logical form of measurement but perhaps the most difficult to visualize.

Last edited by jswinden; 12-24-2010 at 05:42 PM.
jswinden is offline   Reply With Quote
Old 12-25-2010, 04:51 AM   #5
kartu
PRS+ author
kartu ought to be getting tired of karma fortunes by now.kartu ought to be getting tired of karma fortunes by now.kartu ought to be getting tired of karma fortunes by now.kartu ought to be getting tired of karma fortunes by now.kartu ought to be getting tired of karma fortunes by now.kartu ought to be getting tired of karma fortunes by now.kartu ought to be getting tired of karma fortunes by now.kartu ought to be getting tired of karma fortunes by now.kartu ought to be getting tired of karma fortunes by now.kartu ought to be getting tired of karma fortunes by now.kartu ought to be getting tired of karma fortunes by now.
 
Posts: 1,637
Karma: 2446233
Join Date: Dec 2007
Device: Sony PRS-300, 505, 600, 650, 950
Viewers on Sony use "dpi" parameter which differs from reader to reader, but is easy to change. Downside of changing it would be that EBL wouldn't be able to pre-format books for custom DPI values.
kartu is offline   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
PRS-650 Resolution of standby screen pictures yacoob Sony Reader 11 10-04-2010 07:17 PM
DR800 The working (usable) screen resolution PaulS iRex 7 04-23-2010 01:27 PM
PRS-600 Resolution for '6' inch screen var89 Sony Reader 5 02-12-2010 08:09 AM
5" vs 6" resolution and words per screen Wally Which one should I buy? 6 12-17-2009 12:04 AM
When will there be a COLOR iLiad with larger screen (and higher resolution)? yuliang iRex 18 07-16-2007 09:14 PM


All times are GMT -4. The time now is 05:23 PM.


MobileRead.com is a privately owned, operated and funded community.