Why do .gif files slow down?

[Stg-Flame]

As of late, I have been getting into astronomy and I have been finding a great deal of pictures dedicated to that subject. I have also found numerous .gif images that pertain to astronomy as well.

Anyways, I plan on using some of those pictures/files for presentations I will be doing in the fall semester in my Astronomy class. The only problem that I am having isn't while streaming them from a website; the problem lies after I save the .gif to my computer. When I save a .gif to my computer, the animation slows down considerably. It isn't a problem with the smaller files, but with the longer ones (ex. size comparison in planets) the speed is so slow, it almost isn't worth watching anymore.

Does anyone know why the .gif images slow down after I save them to my computer, and more importantly, how do I prevent this from happening?

 

[Roguestar]

I think, actually, it may depend on the browser you are using to view them initially before you save them to your PC. If I recall correctly, Opera used to (and still does) play animated gifs slightly faster compared to Internet Explorer, which uses the same method as your viewing of them offline. So, I don't think the gifs themselves have actually been changed, it just may be that your playback of them has been slowed. Although, from the amount of slowdown you are describing it might not be that simple an explanation. Have you tried opening the files in something like Adobe Imageready and having a look at the timing set between the frames?

 

[wwswimming]

it would be helpful to have more information about file sizes.

Ulead GIF Animator and maybe Sony Vegas Studio & Flash Video Encoder
(FVE) might be helpful converting them to other formats & compressing them.

i just tried it on an animated GIF, with FVE. it converted it.

Adobe has a 30 day Flash demo so you could try it. one of the constraints
with FVE is that it only (i think) creates *.flv's - you have to use Flash to
present them.

 

[corkyg]

I use animated GIF files frequently - even in email. The displayed frame rate results in the perceived "motion." That really depends on what software you use to view it. For general viewing of animated GIF files stored in my computer, I use Irfanview. Works perfectly.