Why do jpegs render darker in browsers ?

[Usjes]

Hi,

I am preparing some jpeg photos for display but I don't know in what software they will ultimately be viewed. I have noticed that they appear darker in browsers (IE 6.0 and Firefox 3.0) with respect to how they appear in photo editing software (Ulead and Adobe). I had expected that all the brightness/contrast information would be contained in the jpeg file so I would expect it to render exactly the same in any software on given hardware. Does anyone know why this happens ? Is my observation true in general ? I have googled and found a number of people on auction sites noting the same effect and suggesting deliberately brightening photos before uploading them. Does anyone know why this happens or if there is anything I can do to the jpeg files so they will display the same in all software?

Thanks,

Usjes.

 

[~Stella~]

I have also noticed that they are much darker when I post them via photobucket or on blogger (worse in PB). It's annoying to say they least.

PSE has a "save for web" option...not sure if that would help or not; I've never used it.

I'll be interested to know the answer to this one.

 

[polymoog]

I mentioned once in a thread of mine that I was unhappy with my jpegs and how they differed quite substantially from the psds. Obiously jpeg is a lossy format and once can't expect perfect results, but the reponse I got from my thread was to check which colourspace I was working in. After looking around on the web the concensus would seem to be that web images such as jpeg should be saved in sRGB colourspace.

I have since found a forum which has a number of discussions on the subject, so you might want to take a look there :

Digital Darkroom forum from Photo.net -- Color Management>Color Space

You might also want to check out this guys article :

Preparing Images for the Web

Re Photobucket, I don't know how or why, but PB messes up images, I have lost count of how many peeople I've read about having probs with hosting files there, and I don't like how my pics look after being uploaded there, so I would say avoid them at all costs ...