Change in photo after upload?

[paleydp]

Oh great photography gurus, it is just me, or are some images changed by the upload process? I took some pics, edited them in photoshop, where they looked pretty good. After uploading them to both yahoo and penturners, they don't look as clear and seem to my eyes to be darker. Do I need to change my photo editing or my glasses?
Thanks,
Denise

 

[Daniel]

Denise,
I have noticed that soem of my photos change when uploaded. I have no idea why. I have also not fugured out haw to estimate the final viewing size either. this is one that will have to be answered by the computer guys.

 

[jeff]

Denise, email me the original photo and I'll compare it to what ended up on the server. There should not be any difference, but anything is possible!! Send it to admin@penturners.org

 

[Daniel]

Jeff,
I have always taken it as one of the effects of the pic being a different size than I see it in my editor or something. I have noticed it anywhere I post pictures not just here.in fact they come out more consistant on thsi sight than on alot of others.

 

[melchioe]

The color balance in general should not be altered due to the place the file resides - if you are looking at the same file on the same monitor, it shouldn't matter if the file is on your local PC or on the penturners.org server. There aren't any web servers that modify colors (at least not that I know of, and I've been in computing far longer than I like to admit, and have done quite a bit of tech support for graphic artists, and some of the color concepts have "rubbed off" on me.)

That said, different monitors have different color balances, and even on the same monitor one picture can appear dramatically different at different times of day, with different numbers of lamps on in the room, etc. You've probably been in Best Buy or some other superstore looking at TVs with the same picture on a whole wall of tubes, and it's startling how different they all look. Same thing applies to computer screens.

There's a whole science (or art) of making colors accurate, and a few years ago Apple came up with the ColorSync standard; Microsoft has created its own system called Image Color Management (ICM). Add in the fact the printing industry has the Pantone (R)Matching System (PMS) for hardcopy color calibration, and the whole thing becomes very complex. What it boils down to is that if one is intent on getting exact color matches, one needs to calibrate the monitor on one's computer to display colors properly. And if you want to print them, then you gotta do the same thing for the printer...

It winds up being more work than most people want to do. Myself, I don't worry about it on my home PC (just like I don't spend days getting the stereo balance and frequency response perfect on my home stereo, while when I'm in the recording studio, I am fanatical about it.)

 

[melchioe]

The final viewing size is another thing that is difficult to determine, mostly since people have their monitors set differently. Many computers today come with their screen resolution set to 1024 pixels wide by 768 pixels tall(see below for a definition of 'pixel').

My friends who are a little older (or refuse to get better glasses because it would mean they're getting older set their monitors to 800 pixels wide by 600 pixels tall. So on a computer set to 1024x768, a picture that has been edited to 850x650 will probably display properly and take up most the screen, while the same picture on a computer set to 800x600 will get scroll bars on the sides and it mightbe harder to view. My home laptop (on which I am typing this) is set to 1024x768; my home desktop is set to 1280 x 1024; and my work computer is set to 1600x1200.

The lesson in that is that if your monitor is set to 1024x768 or higher, you should be aware that the pictures you edit on that screen that take up a lot of the screen will probably overflow some of the lower resolution screens.

The "lowest" standard resolution for computer screens is 640 pixels wide by 480 pixels tall. Since few computers are actually set to that low of a resolution, editing your pictures to be no more than 640 pixels wide and no more than 480 pixels tall will usually provide both a sufficiently large picture for good viewing and a sufficiently small picture to not require scrolling.

*Pixel: the smallest discrete component of an image or picture on a computer screen - a colored dot. If you look very closely at computer screens (or newspaper photos, for that matter), you'll see a bunch of little dots making up the picture.

 

[paleydp]

Thanks for the responses, all. Posted this originally from work, where the images are truely darker (this monitor seems to blue everything up a bit, as well), so it must be the monitor here. At home, checked original against uploaded (now downloaded) version side by side and they appear same, although one is slightly less clear depending on which one I focus on first (those glasses again). Guess I just need to work more with the camera.
Thanks again.