Apologies if this is not the right place - I couldn't find a more suitable forum.

I am producing animated gifs by exporting a FCP sequence through Compressor to a tiff image sequence. The frame rate is 15 fps and so for a 13 second sequence I get 200 images. I am then importing the sequence into Photoshop, specifying the frame rate and saving (using Save for Web) as a gif.

If I play the gif in Firefox, it runs to speed and lasts 13 seconds. But in IE or Safari, it seems to run at 2/3 spped and lasts 20 seconds. I have taken the export frame rate down to 10 fps and the same happens. If I fudge the frame rate, telling Photoshop that the 15 fps image sequence is 21 fps, it will play at the correct speed in IE and Safari but too fast in Firefox. In each case the play speed has been checked over a number of repetitions of a looping gif so it is not just the first play.

Anyone experienced this or, better still, found the cause?

Many thanks