What is a Working Space?
If I intended to build a boat I would use a boathouse. If I decided on building a car I would use a garage and if it was a Airfix car I’d do it in my “shack”. These are analogous to working spaces. The working space needs to be big enough to hold the thing you are working on or you will have to leave things off.
Software such as Photoshop requires you to decide if you are going to work in a boathouse, a garage, or a shack. In Photoshop the common choices of working space are ProPhoto RGB, Adobe RGB and sRGB (there are lots of others). In the analogy the boathouse = ProPhoto, Garage = Adobe RGB and the shack = sRGB.
So you can build the Airfix car in a boathouse and similarly you can define your working space as ProPhoto in Photoshop. In the days before memory and computing power became cheap ProPhoto would have taxed your computer. The reason for this is as it is such a big working space the recommendation is to work in 16 bits. That is now not a problem.
In Lightroom Adobe have taken the choice away from the user and provide a working space called Melissa which is effectively a version of ProPhoto which is better for manipulation arithmetic. (Gamma 1)
ProPhoto is an all-encompassing working space, it is so large it includes all input and output devices. Nothing ever has to be left our whilst you are working/building. However you do have to get it through the door!
I use sRGB as my working space and do not see any negative effects with my images or prints in using the “small” working space. In fact your output must be sRGB for web use if you want to be confident viewers see the colours you intend. As I use a small working space I have to decide what to do with the colours outside that working space when I enter the working space. How these are handled is called Intent.
With modern multi ink printers the colours they can print can exceed the working space of Adobe RGB in some colours. So if you chose Adobe RGB as your working space you will have to leave some printable colours out if they are in your image. This is done when you image goes into the working space. Again the way these are handled is called Intent.
All working spaces contain colours that cannot be printed and modern printers can print colours that are outside Adobe RGB and sRGB but not ProPhoto as that is all-encompassing.
So the reference to getting it out of the door is that colours contained outside the destination printer gamut (The working space of the printer) must be handled so that they print acceptably. This is intent. It needs a separate explanation.
The choice of working space will have a much less significant effect upon your images than failing to get the colour management correct. Therefore my advice is to make your life easy and stick to sRGB throughout. If you are confident in colour management then use ProPhoto in Photoshop (As Adobe do in Lightroom) as that will maximise your gamut (colours) at the printer.
See this a bit bigger HERE.