MiriamJ
06-22-200722nd June 2007, 07:36 AM
We shoot RAW to get the most information available to us, but often we throw that information away prior to and in the editing process resulting in less detail and poor color. Here's some thoughts on editing with full information:
File type:
Set your RAW converter to convert to TIF rather than .jpg. A JPeg has less information than a TIF, first because there is a smaller bit depth, (less information per pixel). Also, even worse, a .jpg is a compressed file, which means that information is thrown away to save space. What this means in the end is posterization. I think of posterization as a lack of smooth transaction in detail.
Here's an excellent, short tutorial that explains about posterization and also shows you what it looks like. http://www.cambridgeincolour.com/tut...terization.htm
While you're at it, set your RAW converter to 16-bit TIF, instead of 8-bit. Again, much more detail available resulting in a better edited photo.
Color space:
Another thing that helps is to use ProPhoto color space. A color space is the gamut, (the amount of colors available for your use). Unless you are using ProPhoto when you convert to TIF, you are using less colors when you are editing, which greatly affects the colors in the end.
Check out this page: http://www.luminous-landscape.com/tu...hoto-rgb.shtml , especially figure 3b, to see how many colors you are limited to when using another color space such as Adobe RGB.
Additional information added 6/23/07: There can be posterization with too many colors. BetaRGB and processing in LAB color (image->mode->lab color) is better than ProPhoto.
However, if Beta RGB is not available, you can use the ProPhoto color space, then temporarily assign, (not convert) a smaller gamut such as AdobeRGB. Another alternative is to go into your color settings and use a 20% to 30% desaturation setting on your monitor. Check out this post for more information: http://www.nikoncafe.com/vforums/sho...light=prophoto Very interesting!
Clipping:
The other thing that helps is to be very careful in both your RAW converter and Photoshop to keep a close eye on the histograms to make sure none of your channels are clipped, losing valuable information. I think of a histogram as a display of my photo in graph form. This shows you what clipping looks like on a histogram, and will also give you more information on histograms. http://www.cambridgeincolour.com/tut...istograms1.htm Look around the middle of the page for a clipped histogram.
Converting after editing:
You will need some additional steps after you finish your editing in Photoshop. You won't want to finish as a TIF, the file's way too big and some viewers will not recognize it. Also, things like Internet Browsers, photoviewers, often don't recognize ProPhoto, and will display an off-color image.
So, after the Photoshop editing is finished, first I rename and save the image as a full-sized, ProPhoto color space, 16-bit TIFF, because once you convert, you lose information that you will never be able to retrieve again.
After this save, I resize the photo.
Next, I make sure I'm working in RGB mode, (image pulldown->Mode->RGB color). Then I change my color space to sRGB (Edit->convert to profile->sRGB IECxxxxxxx), if I'm posting the photo to the internet or to my printer/paper type profile if I'm going to print. Next, I change my bit depth to 8-bit, so I'll be able to save as a .jpg. Image->mode->8-bits channel. Last, when I save the file, I save as a .jpg.
Added 06/23/07. This I wasn't sure about: It just made sense to me, and I just now confirmed, it's best to convert to your intended color space and then to 8-bit.
If you're printing, it makes sense to use a printer profile. Assuming your monitor is correctly calibrated, it corrects the photo so that information sent to the printer is correct. I use one downloaded from www.drycreekphoto.com for the printer at my local Costco. More information about color spaces and printer profiles can be found at: http://www.drycreekphoto.com/Learn/color_management.htm
By the way, your output still will not be correct unless your monitor has been correctly calibrated. I'm using the inexpensive Huey that also resets my monitor according to the changing room lighting as I'm working.
Hope this is helpful.
This is just what I've picked up that has helped me. If anyone reading this finds any inaccuracies, I'd be grateful for the clarification. :)
Here's further reading on profile connection space, (the why of color spaces) by a very knowledgable person: http://www.nikoncafe.com/vforums/showthread.php?t=86287&highlight=prophoto
File type:
Set your RAW converter to convert to TIF rather than .jpg. A JPeg has less information than a TIF, first because there is a smaller bit depth, (less information per pixel). Also, even worse, a .jpg is a compressed file, which means that information is thrown away to save space. What this means in the end is posterization. I think of posterization as a lack of smooth transaction in detail.
Here's an excellent, short tutorial that explains about posterization and also shows you what it looks like. http://www.cambridgeincolour.com/tut...terization.htm
While you're at it, set your RAW converter to 16-bit TIF, instead of 8-bit. Again, much more detail available resulting in a better edited photo.
Color space:
Another thing that helps is to use ProPhoto color space. A color space is the gamut, (the amount of colors available for your use). Unless you are using ProPhoto when you convert to TIF, you are using less colors when you are editing, which greatly affects the colors in the end.
Check out this page: http://www.luminous-landscape.com/tu...hoto-rgb.shtml , especially figure 3b, to see how many colors you are limited to when using another color space such as Adobe RGB.
Additional information added 6/23/07: There can be posterization with too many colors. BetaRGB and processing in LAB color (image->mode->lab color) is better than ProPhoto.
However, if Beta RGB is not available, you can use the ProPhoto color space, then temporarily assign, (not convert) a smaller gamut such as AdobeRGB. Another alternative is to go into your color settings and use a 20% to 30% desaturation setting on your monitor. Check out this post for more information: http://www.nikoncafe.com/vforums/sho...light=prophoto Very interesting!
Clipping:
The other thing that helps is to be very careful in both your RAW converter and Photoshop to keep a close eye on the histograms to make sure none of your channels are clipped, losing valuable information. I think of a histogram as a display of my photo in graph form. This shows you what clipping looks like on a histogram, and will also give you more information on histograms. http://www.cambridgeincolour.com/tut...istograms1.htm Look around the middle of the page for a clipped histogram.
Converting after editing:
You will need some additional steps after you finish your editing in Photoshop. You won't want to finish as a TIF, the file's way too big and some viewers will not recognize it. Also, things like Internet Browsers, photoviewers, often don't recognize ProPhoto, and will display an off-color image.
So, after the Photoshop editing is finished, first I rename and save the image as a full-sized, ProPhoto color space, 16-bit TIFF, because once you convert, you lose information that you will never be able to retrieve again.
After this save, I resize the photo.
Next, I make sure I'm working in RGB mode, (image pulldown->Mode->RGB color). Then I change my color space to sRGB (Edit->convert to profile->sRGB IECxxxxxxx), if I'm posting the photo to the internet or to my printer/paper type profile if I'm going to print. Next, I change my bit depth to 8-bit, so I'll be able to save as a .jpg. Image->mode->8-bits channel. Last, when I save the file, I save as a .jpg.
Added 06/23/07. This I wasn't sure about: It just made sense to me, and I just now confirmed, it's best to convert to your intended color space and then to 8-bit.
If you're printing, it makes sense to use a printer profile. Assuming your monitor is correctly calibrated, it corrects the photo so that information sent to the printer is correct. I use one downloaded from www.drycreekphoto.com for the printer at my local Costco. More information about color spaces and printer profiles can be found at: http://www.drycreekphoto.com/Learn/color_management.htm
By the way, your output still will not be correct unless your monitor has been correctly calibrated. I'm using the inexpensive Huey that also resets my monitor according to the changing room lighting as I'm working.
Hope this is helpful.
This is just what I've picked up that has helped me. If anyone reading this finds any inaccuracies, I'd be grateful for the clarification. :)
Here's further reading on profile connection space, (the why of color spaces) by a very knowledgable person: http://www.nikoncafe.com/vforums/showthread.php?t=86287&highlight=prophoto