Do egg shell color change shades from day to day?

[ChicksNQuails]

I have 14 chickens and have been trying to figure out who is laying which egg. I'm pretty certain that the shade of the egg shells may change slightly from day to day, which is making it pretty confusing. It's just a slight difference, from a medium tan to a darker tan or med brown to darker brown. Have you all experienced this?

 

[johnlogan]

Sometimes this is the case, expecially if they have just started to lay. The pullets are getting everything figured out. Usually mature hens are pretty consistant from day to day, but if they quit for a time when they start back you may notice a difference. A lot of time the shape of an egg is a good indicator as to who layed it.

 

[Kelsie2290]

Ya, mine do the same thing, a lot of times the shell colors will vary slightly from day to day. There are various things that determine shell color and everything from the weather to the size of the egg to any kind of stress may slightly affect the shell color. If you have hens that lay the same general color eggs, don't think you can accurately use shell color to figure out who is laying.
http://edis.ifas.ufl.edu/vm047
http://www.blpbooks.co.uk/articles/egg_shell_colour/egg_shell_colour.php