Friday, April 22, 2005

Bitmaps vs. Vectors

In response to Eric's question regarding "vectors" and for all those of you out there who always wanted to know but were too shy to ask :).

The following are excerpts from a web article written by the lovely, talented and extremely knowledgeable Sue Chastain published by

Bitmap images are resolution dependent. Resolution refers to the number of pixels in an image and is usually stated as dpi (dots per inch) or ppi (pixels per inch). Bitmap images are displayed on your computer screen at screen resolution: 72 or 96 ppi. However, when printing bitmaps, your printer needs much more image data than a monitor. In order to render a bitmap image accurately, the typical desktop printer needs 150-300 ppi. If you've ever wondered why your 300 dpi scanned image appears so much larger on your monitor, this is why.

Vector images are made up of many individual, scalable objects. These objects are defined by mathematical equations rather than pixels, so they always render at the highest quality. Objects may consist of lines, curves, and shapes with editable attributes such as color, fill, and outline. Changing the attributes of a vector object does not effect the object itself. You can freely change any number of object attributes without destroying the basic object. An object can be modified not only by changing its attributes, but also by shaping and transforming it using nodes and control handles.

Because they're scalable, vector-based images are resolution independent. You can increase and decrease the size of vector images to any degree and your lines will remain crisp and sharp, both on screen and in print. Fonts are a type of vector object.

For the entire Sue Chastain's article please click Here.

© copyright 2005 Sue Chastain/, excerpts of the original article are reproduced here with permission, for review and educational purposes to the benefit of the copyright holder.


Eric said...

Alberto, Thank you for posting this as it helped me to understand exactly what people have been talking about around me. I followed the link to as well and found some very insightful articles. I have not gotten my copy of illistrator yet, but it should arrive by monday or teusday hopefully.

Thanks again for the knowledge,
- Eric

Process Junkie said...

Don't thank me, Sue wrote the article :).


Eric said...

I finally recieved my copy of AI and woah is it intimidating. So far I have not gotten it to do one thing I have wanted, but indirectly learned how to do some things that looked cool anyway. Ah before I forget I wanted to ask your advice. Is it possible to turn jpeg pictures into vector formats? I have a picture that I want made into a sticker but the sticker guys told me that it needs to be in vector format. I was hoping I could do this transformation in AI.

- Eric