Knowledge Article 0201:
How do I get the best image quality in my project?

Applicability: SellFolio 4.0 Complete only

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Background

There are two types of image files:

• Raster-based: these types of images are composed of pixels, or small dots.  Examples of raster-based images are .JPG, .BMP, .TIF, .PNG, .PSD, .GIF.  These are used for photos.

• Vector-based: these types of images are composed of mathematical calculations that draw lines and curves when they are displayed.  Examples of vector-based images are .AI, .WMF, .CDR.  It's important to note that when the lines and curves are drawn, they are drawn as pixels, because that's the only way a computer monitor can generate a display.  These are commonly used for logos, fonts, line-drawings, etc.
  
  ***NOTE: An exception to the above is the .SWF file (known as a "Flash file"), because .SWF files have the ability to contain both raster and vector images simultaneously.  A .SWF file can be thought of as a "hybrid" image, but it's also much more, being capable of animation, application programming, video, and much more.

Photos are always raster-based.  Line-based images, such as logos and text, are almost always vector-based.

The Big Tradeoff

A point you must always remember is that pixels cannot shrink or stretch.  A pixel is always a pixel.  For this reason, raster-based images do not scale very well.  This is why photos in a SellFolio project might appear distorted when stretched/shrunken. 

Vector-based images, on the other hand, scale perfectly in all situations, but they can't display photographic imagery.  So, there's the problem—you need to show photographic imagery in your SellFolio project, but the photos are not displaying well.  The reason is that the photos are being stretched or shrunken, and all those pixels are either being "dropped-out" (when the photo is sized too small), or pixels are having to be "added" (when the photo is stretched larger than its native size).  This causes photographic images to be jagged or pixilated.

Again, can you get a photograph to exist in vector form, so that it always scales perfectly?  No.

How SellFolio Displays Images

There are two modes of display in SellFolio, which you establish in Step 2-F in SellFolio Builder:

• Fill the available screen area: this mode is good because it gives the largest viewing area for your project.  But, everyone has different monitor sizes and screen resolutions.  This means that your project will always shrink or stretch to fit the viewer's available screen area.  Accordingly, all imagery in your project will also shrink or stretch.

• Fixed-size: this mode is good because it has the capability of guaranteeing that your images display perfectly, if you do things right.  But, because your project will always display in a fixed-size, some users may see the project to be smaller than you'd like, while other users might have to scroll around the screen to view the project.  This is because their available viewing area might be bigger or smaller than the fixed-size that you've chosen.

When building your project, you need to take these factors into consideration.  Again, these are tradeoffs.

But, I'm using 3,200x2,400-sized images, in 300dpi.  Shouldn't that display well?

Now, remember these points:

• Large-dimension images (in pixels) are only suitable for printed output.  They are not suitable for display on a monitor.  That 3,200x2,400-sized image is way too large for your SellFolio project.

• The "dpi" parameter has nothing to do with display on a computer monitor.  This parameter only relates to printed output.  For the purposes of SellFolio, completely forget about that "300 dpi" setting.  For monitor-based output, a 800x600 300-dpi image will display exactly the same as a 800x600 75-dpi image.

• Everyone's screen resolution is different.  For instance, one possible typical screen resolution is 1,280x1,024 pixels.  Another would be 1,024x768 pixels.  So, if you've got that huge 3,200x2,400  pixel raster image, you can clearly see that it's way too large for display on a typical monitor.  The only way to display that raster image is to "shrink it down."  Of course, though, it really can't be "shrunken down."  Again, pixels can't be stretched or shrunken.  Instead, the software must selectively drop-out pixels or add them, as appropriate.  This causes image distortion.

• In addition to everyone having different screen resolutions, you also have to keep in mind that everyone's web browsers have differing amounts of available display area.  As users have more toolbars, status bars, etc., in view, that cuts down on the available display area.  The point here is that you have no idea how many pixels your viewer really has available to display.

So, what do I do?

OPTION 1: If you want your project to fill whatever available display area the user has, then in Step 2-F, use the "This project should fill the available window" option.  But, this also means that the SellFolio project will stretch or shrink accordingly, to fit the user's display area.  Accordingly, all raster images (JPG photos, etc.) in the project will have to resize, causing some degree of distortion.  To minimize this effect, you'll have to make your best guess as to what dimensions of pixel display area your viewers will have.  In general, raster images that are 1,024x768 pixels will be a good start.  But, there will always be some shrinking or stretching of the project, and hence the raster images within it, on all users systems, with this display option in SellFolio.  The advantage is that the project fills the available display area.

OPTION 2: Use a fixed-size in Step 2-F, such as "This project should display in 800x600 pixel size."  Your project will always display in that chosen size.  If a user views the project in their web browser, and the web browser has 1,098x879 pixels available for display, then your 800x600 project will fit nicely within that area.  They'll see a border area around your project.  If, on the other hand, the viewer has a smaller screen resolution, and they've got lots of toolbars displayed in their web browser, their available display area in the browser might be something like 742x581 pixels.  In this case, your 800x600 project will be too large, and the user will have to scroll around to see all parts.

If you use one of the fixed-size options in SellFolio, import your images to these sizes:

• If you're using the 640x480 size: Use a photo-editing program to size your images no larger than 640x480 (for instance, a 500x470 size image will work).   Import them in Live Layout mode, and using the Scale % stepper at the bottom of the screen, give your photos a percentage of 100.

• If you're using the 800x600 size: Use a photo-editing program to size your images no larger than 800x600 (for instance, a 730x570 size image will work).  Import them in Live Layout mode, and using the Scale % stepper at the bottom of the screen, give your photos a percentage of 80.

• If you're using the 1,024x768 size: Use a photo-editing program to size your images no larger than 1,024x768 (for instance, a 900x733 size image will work).  Import them in Live Layout mode, and using the Scale % stepper at the bottom of the screen, give your photos a percentage of 63.