Posted by Philip Ruder on October 9, 2006 at 12:52 PM
Hi William
First, I'm not an expert on colour space but I did read somtime ago to use the widest gamut posible, at that time pro photo rgb, so I use this in C1Pro and Photoshop CS. I convert to srgb for web use. Is this better for nature who knows, but it works for me I also use Mange Nilson Profiles for the 1D2 and 10D.
Hi I use argb (1998) the only trouble is that most digital SLR's raw files are 12bit and most people edit them as 16-bit so it's making up 4 bits of information and there is only a few printers that actually print in true 16 bit so I can't see the point in using anything bigger than aRGB.
Are you talking about the source colour space or output colour space - ie what to set for your camera before you do any processing, or what to set for printing or sending to someone?
Bit depth and colour space are not related in any way, the only advantage to working with a 16 bit file is smoother colour transitions within the colour space.
As to which colour space you should be using my vote is for aRGB, therefore source (camera) and working space within your chosen software should be set to aRGB. Pro Photo RGB is probably overkill for most purposes (same with any wide Gamut RGB), but if it is an important never to be repeated image Pro Photo in 16 bit may be the way to go.
Most desktop printers are able to reproduce a gamut resembling aRGB also aRGB is capable of providing the best conversion to CMYK......
Photoshop works internally in the LAB colour space anyway, aRGB or sRGB are just tags that tell the software how to treat the image.
So if you are purposing for general use and print then aRGB should be your target gamut, if purposing solely for the web or external print shops then sRGB. (it is still better to work in aRGB and convert as the last or near last step)
HTH and makes sense (typing quick before I have to go to a meeting)
Hi Phil unfortunately I think I will have to disagree with you it is important on how many bits of information you have to start out with as these bits of information actually create your colour space. The insert below is not written by me but a much more intelligent person.
Phillip.
Color space
The RGB color model is implemented in different ways, depending on the capabilities of the system used. By far the most common general-use incarnation as of 2006 is the 24-bit implementation, with 8 bits, or 256 discrete levels of color per channel. Any color space based on such a 24-bit RGB model is thus limited to a gamut of 256¡Á256¡Á256 ¡Ö 16.7 million colors. Some implementations use 16 bits per component, resulting in the same range with a greater density of distinct colors. This is especially important when working with wide-gamut color spaces (where most of the more common colors are located relatively close together), or when a large number of digital filtering algorithms are used consecutively. The same principle applies for any color spaces based on the same color model, but implemented in different bit depths.
LOL, just reread your quote and it is saying exacly the same as I was only in a more complicated way....
Hi Phil...
Sort of yes.... the higher the bit depth the 'smoother' the transitions as I stated in my reply, the bit depth does not have any effect on what colour is contained within the gamut of the colour space, a colour that is within gamut is within whether it is 8 or 16 bit also an out of gamut colour will be out whether it is 8 or 16 bit, the 16 bit part means that you can achieve greater accuracy of the colours within a specific gamut be it aRGB or sRGB etc., whether these can be reproduced at the end of the day is another matter....
Discussion
7 repliesHopefullly I can get a few views here on this .
William
First, I'm not an expert on colour space but I did read somtime ago to use the widest gamut posible, at that time pro photo rgb, so I use this in C1Pro and Photoshop CS. I convert to srgb for web use. Is this better for nature who knows, but it works for me
Phil
Phillip.
Are you talking about the source colour space or output colour space - ie what to set for your camera before you do any processing, or what to set for printing or sending to someone?
Bit depth and colour space are not related in any way, the only advantage to working with a 16 bit file is smoother colour transitions within the colour space.
As to which colour space you should be using my vote is for aRGB, therefore source (camera) and working space within your chosen software should be set to aRGB. Pro Photo RGB is probably overkill for most purposes (same with any wide Gamut RGB), but if it is an important never to be repeated image Pro Photo in 16 bit may be the way to go.
Most desktop printers are able to reproduce a gamut resembling aRGB also aRGB is capable of providing the best conversion to CMYK......
Photoshop works internally in the LAB colour space anyway, aRGB or sRGB are just tags that tell the software how to treat the image.
So if you are purposing for general use and print then aRGB should be your target gamut, if purposing solely for the web or external print shops then sRGB. (it is still better to work in aRGB and convert as the last or near last step)
HTH and makes sense (typing quick before I have to go to a meeting)
Phil
Phillip.
Color space
The RGB color model is implemented in different ways, depending on the capabilities of the system used. By far the most common general-use incarnation as of 2006 is the 24-bit implementation, with 8 bits, or 256 discrete levels of color per channel. Any color space based on such a 24-bit RGB model is thus limited to a gamut of 256¡Á256¡Á256 ¡Ö 16.7 million colors. Some implementations use 16 bits per component, resulting in the same range with a greater density of distinct colors. This is especially important when working with wide-gamut color spaces (where most of the more common colors are located relatively close together), or when a large number of digital filtering algorithms are used consecutively. The same principle applies for any color spaces based on the same color model, but implemented in different bit depths.
Hi Phil...
Sort of yes.... the higher the bit depth the 'smoother' the transitions as I stated in my reply, the bit depth does not have any effect on what colour is contained within the gamut of the colour space, a colour that is within gamut is within whether it is 8 or 16 bit also an out of gamut colour will be out whether it is 8 or 16 bit, the 16 bit part means that you can achieve greater accuracy of the colours within a specific gamut be it aRGB or sRGB etc., whether these can be reproduced at the end of the day is another matter....
All the best & speak soon
Phil