Re: [APML] Reflecting on Cygnus

[Chuck Vaughn <aa6g@aa6g.org>]

  Wei-Hao,

Thanks for the comparisons. In Safari the first 3 images look the  
same. The last image (lower right) is brighter. In all the other  
browsers all 4 images look identical to the lower right image which  
looks the same as in Safari. This would support my observation that  
most browsers perform no color management.

Why do you say that most browsers treat images as sRGB? It looks to  
me that images are displayed in whatever the working color space  
happens to be on one's computer. That's not necessarily sRGB.

If most browsers are not managing color then it's impossible for you  
to display an image that will look similar to everyone.

Chuck

-------------------------------


> Hi Rob,
> This is beautiful.
>
> Chuck, your question is a good one.  Please take a look at this page:
> http://www.ifa.hawaii.edu/~wang/misc/color_profiles.htm
> I prepared the images in Photoshop using Adobe RGB and sRGB profiles.
> Whne I saved each of them, I saved one with the correct color profile
> embedded and another one without embedding the color profile.
>
> Most browsers seem to ignore the profiles and treat the images as  
> sRGB,
> no matter in Mac or in Windows.  So an sRGB image will always be
> interpreted correctly, no matter if there is an embedded profile or  
> not.
> Among the four images in the webpage, the top two always have the  
> correct
> color (well, the color I wish to present to people and the color I saw
> in Photoshop)
> although one of them doesn't have an embedded profile at all.  The  
> lower two
> images look nice, too.  But that's not the color I saw in Photoshop.
>
>
>
>> From this point of view, it is the safest to convert the image into
>>
>>
> sRGB before you
> save it.  In this way, no matter which browser the readers use and no
> matter if the
> profile is embedded or not, the result will look correct.
>
> On the other hand, if you open the page with Safari.  You will see the
> lower-left
> image also has the correct color.  For this to happen, the reader  
> has to have
> Safari and I have to remember to embedded the profile.  This just  
> doesn't
> happen all the time.  Most people don't have Safari and sometime I  
> forget
> to check the color profile box when I save the file.
>
> The conclusion is, do remember to convert the image into sRGB  
> before posting
> it to internet.  sRGB is the default of most browsers.
>
> Cheers,
> Wei-Hao

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