About displaying images on web
in [Dreamweaver]
|
From: Duncan Kennedy on 30 Apr 2010 14:11 LarryM <NotInUse(a)telia.com> wrote: > On Fri, 30 Apr 2010 10:59:48 +0100, > nospam(a)nospamottersonbg.couk (Duncan Kennedy) wrote: > > > >Is it absolutely essential to use zoom? > > Hi Duncan, > > let us for the discussion say that the visitor uses zoom to > 150%. > ANd let us say that downloading time is no issue. > > The technical question is: Could an image which in 72 ppi is > 10 inches wide be displayed with a width of 5 inches on a > web page? > I see what you mean. It isn't impossible to zoom with Flash but that would be a bit expensive if you don't already have it and I have to be honest - I haven't done it. And Flash's ability to zoom is really directed at vector images rather than photos, which are bitmaps. But Flash doesn't detect that your visitor has chosen to zoom in as a default. I suspect the only answer to that, maintaining quality, would be to put a warning about quality and best viewing on the page as any zooming is going to damage quality. Think in terms of each pixel suddenly becoming 1.5 pixels in size without any improvement in the original photo and any edge smoolthing starting to get blocky. Combined with a warning about viewing quality, the easier way would still be a "Click here " method - open the second image size in a second page. You could constrict the size to 5ins (but see below) in the fist page and then, with a click, a second page would open with the larger size. That way the visitor would have the option of a bigger photo. Forgetting, for the moment, the resolution variations below, have you experimented with making your original photo 1.5 times the size that you set the HTML size to (a bigger file) and then trying it on a browser set at 150%? I think you can really be the only judge of whether this meets your needs in quality terms at both 100% and 150%. The problem is, of course, just what resolution your readers use. 72ppi is standard for most cheaper monitors (particularly CRTs), 96ppi common for more recent TFTs - but have a look at some of the high resolution ones - from, for example but not exclusively, Dell and Apple. That screws up your size calculations a bit. For example this reasonably inexpensive Dell I'm usng at the moment is running at its default 2048 pixels in a 20 inch width - something like 102 ppi if I work it out right. Because it is a 23" wide format screen I tend to *restrict the size of the browser, rather than trying to make it fill the screen width. It does mean that you can't easily relate pixels to inches for a fixed width. I'm sure there must be other ways, for example, using JavaScript but that's for others to comment, I'm afraid. It would need some way of indentifying those visitors that are setting their browsers to 150% and I'm not convinced this is possible. You could try the official Adobe forum from their web site. -- duncank
From: LarryM on 30 Apr 2010 14:52 Thanks Duncan! So if I would go on with this idea I might look into Flash or Javascript. (OK, I have acess to both... But maybe I wait for some sort of confirmation that it is possible first.. So you have your screen set to 2048 pixels. Then web sites that are made for 800x600 must look rather tiny on your screen. Maybe you then zoom them up to see them properly, see what I mean? And when you do so, some images are getting pixelated.. That's my problem.. BTW what happened to this Dreamweaver usenet group, wasn't it a huge forum earlier? /Larry
From: Your Name on 30 Apr 2010 17:21 > Thanks Harry, > I understand your concern. > > I am a photographer. > My web visitors most likely uses broadband and I don't plan > on putting in megalarge images. > My visitors also are likely to have high resolutons screens > and are likely to see the web browser using some zooming in, > say to 150%. > When doing this zooming the images get a little bit blurry > which is a pity. > > I am looking for a way to preserve sharpness even if the > image is somewhat zoomed in. > My little test with Photoshop made images which then are put > into a Dreamweaver built web page seem to fail. > The images are displayed in 72 ppi mode, the 144 ppi is just > double as large as the 72 ppi image (same size in inches). The web browser and Dreamweaver ignore the resolution settings of images and simply display them at "72ppi" (or whatever the screen is), meaning a 144ppi will be twice as big, as you've discovered. At the simplest level, once you've inserted the image into your Dreamweaver page, you can manually scale it using the same handles as you would for an image in Word or any page layout application (hold down the Shift key while dragging a corner handle to keep the image in perspective). You can also scale it using the Properties / Inspector palette or by manually editing the code. The HTML code will automatically add the appropriate size tags to the image. e.g. <IMG SRC="Images/MyImage.jpg" WIDTH="46" HEIGHT="32"> BUT, I haven't actually tried this, so I don't know what happens when someone zooms the web page - you may or may not get a clearer image using the extra downloaded pixels (no doubt the results will vary with different browsers). Helpfull Harry :o) ..
From: Duncan Kennedy on 30 Apr 2010 17:38 LarryM <NotInUse(a)telia.com> wrote: > Thanks Duncan! > > So if I would go on with this idea I might look into Flash > or Javascript. (OK, I have acess to both... > But maybe I wait for some sort of confirmation that it is > possible first.. I have my doubts because it seems to hinge on your pages being able to tell what level f zoom each one is using before adjusting the photo. But if it is possible ity will be some sort of scripting - JavaScript or any of the CGI scripts with which I am not really familiar. Just to let you see what is possible by constraining the dimensions of a photo I have put a simple sample page with camera photos on a near dead site of mine (the site itself is many years old and out of date - used for tests only - and I am changing servers round so this one may disappear at any time!) The large photo of the back with text on it is the original size - the half size one is the same photo constrained to 50% width and height (actually 25%). If you zoom in in a browser the bottom one seems to hold its definition as it grows in size. (Remember all your photos would be the size you expect your visitors to use (150%) but constrained to the equivalent of 100%) URL is http://www.otterson-bg.com/test/norton/nortontest.htm > > So you have your screen set to 2048 pixels. Then web sites > that are made for 800x600 must look rather tiny on your > screen. These days 800 is the normal width but remember the depth is a lot less than 600 on many screens when you think og address bars etc. I dfon't really want to view so little (in depth) of a page by zooming in too much unless the text is very small. > Maybe you then zoom them up to see them properly, see what I > mean? Not really - unless the text is very small. Most pages fill the screen or more vertically. > > BTW what happened to this Dreamweaver usenet group, wasn't > it a huge forum earlier? > Adobe abandoned all of their Usenet groups almost exactly a year ago. They removed them from their servers. The groups still eist as they were mirrorede on many other servers and there are a few of us still around who prefer the format rather than the web forums - but there is no doubt - the Adobe official experts all went off to the forums. -- duncank
From: LarryM on 1 May 2010 03:15
Hi guys, I cannot say how glad I am for this usenet system, allowing amateurs like me to get direct help from experienced people like you! On Sat, 1 May 2010 09:21:42 +1200, "Helpful Harry" <your.name(a)isp.com> wrote: > <IMG SRC="Images/MyImage.jpg" WIDTH="46" HEIGHT="32"> where the image actually is, say 92x64 pixels. So, this is the 'scaling' in HTML... It seems to be a very simple way to 'embed extra pixels' into the image. Duncans nice attached example shows that this could really be the way to go. Of course I will do more testing (file size, download time, sharpness appearance..) to confirm that you really get a better result on images that are slightly zoomed in (125 -150% ?). Thanks again Harry and Duncan! /Larry |