Re: [SlimDevices: Touch] Color Management of Scanned Album Art
jdt7385 wrote: I am unable to achieve good color in album art that I have scanned and added to the music using either dbPoweramp or MP3tag. I scan the art from the CD cover and do modest editing in Photoshop. I use either Adobe RGB or Prophoto profiles. I have tried changing the color profile to sRGB (usually good for web work) and deleting the profile (no color management). No matter what I do the color in the photos in both the dbPoweramp and MP3tag programs and on the screen in Squeezebox are dark and lifeless. What should I do to correct this problem? I use Photoshop CS5. I will appreciate any help you are able to provide. I have figured out what I was doing wrong. I was converting the color profile of the file to sRGB but was doing so after I had already baked' the large gamut ProPhoto profile into the file by flattening it after doing the edits (very limited edits, but that does not matter). I started with an unedited scan, used the sRGB profile, made the simple edits and it looks good. So it appears that I have to process the sRGB and ProPhoto files separately. I sometimes make copies of the album art for copies of CDs that I put into the plastic cases so I produce two files, one for that purpose (4.75 x 4.75) and one for the Squeezebox display, the size of which I reduce by 50%. Thanks to all of you for your comments. jdt7385's Profile: http://forums.slimdevices.com/member.php?userid=56306 View this thread: http://forums.slimdevices.com/showthread.php?t=95637 ___ Touch mailing list Touch@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/touch
Re: [SlimDevices: Touch] Color Management of Scanned Album Art
JJZolx wrote: See if you can find some of the same covers that you've scanned on http://www.albumartexchange.com. If there's a significant difference, then you're obviously doing something wrong. If not, I'd chalk it up to the cheap display on the Touch. He say it also looks wrong in dBpoweramp and mp3tag ,so it seems wrong already there ? Wonder how the file looks when converted to a plain rgb or png or jpeg and look at it not using photoshop , I don't know I assume the more fancy formats like photoshops own can carry gamma channel information embedded to be used by similar applications . And can not photshop itself be tuned to the computer screen you have ? Mnyb's Profile: http://forums.slimdevices.com/member.php?userid=4143 View this thread: http://forums.slimdevices.com/showthread.php?t=95637 ___ Touch mailing list Touch@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/touch
Re: [SlimDevices: Touch] Color Management of Scanned Album Art
JJZolx wrote: See if you can find some of the same covers that you've scanned on http://www.albumartexchange.com. If there's a significant difference, then you're obviously doing something wrong. If not, I'd chalk it up to the cheap display on the Touch. +1 for Album Art Exchange, it's normally my first port of call when adding an album with dBpoweramp CD Ripper, followed by scans if I have the album art to hand. Failing that, I resort to Google. RussellMrgn's Profile: http://forums.slimdevices.com/member.php?userid=29655 View this thread: http://forums.slimdevices.com/showthread.php?t=95637 ___ Touch mailing list Touch@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/touch
Re: [SlimDevices: Touch] Color Management of Scanned Album Art
jdt7385 wrote: I am unable to achieve good color in album art that I have scanned and added to the music using either dbPoweramp or MP3tag. I scan the art from the CD cover and do modest editing in Photoshop. I use either Adobe RGB or Prophoto profiles. I have tried changing the color profile to sRGB (usually good for web work) and deleting the profile (no color management). No matter what I do the color in the photos in both the dbPoweramp and MP3tag programs and on the screen in Squeezebox are dark and lifeless. What should I do to correct this problem? I use Photoshop CS5. sRGB is the profile to use - the colours will look washed out with Adobe RGB and Prophoto will be dark and very grey. Make sure you use the adobe Convert to Profile command NOT the Assign Profile option otherwise it wont actually change the colours. steve-g's Profile: http://forums.slimdevices.com/member.php?userid=52057 View this thread: http://forums.slimdevices.com/showthread.php?t=95637 ___ Touch mailing list Touch@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/touch
[SlimDevices: Touch] Color Management of Scanned Album Art
I am unable to achieve good color in album art that I have scanned and added to the music using either dbPoweramp or MP3tag. I scan the art from the CD cover and do modest editing in Photoshop. I use either Adobe RGB or Prophoto profiles. I have tried changing the color profile to sRGB (usually good for web work) and deleting the profile (no color management). No matter what I do the color in the photos in both the dbPoweramp and MP3tag programs and on the screen in Squeezebox are dark and lifeless. What should I do to correct this problem? I use Photoshop CS5. I will appreciate any help you are able to provide. jdt7385's Profile: http://forums.slimdevices.com/member.php?userid=56306 View this thread: http://forums.slimdevices.com/showthread.php?t=95637 ___ Touch mailing list Touch@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/touch
Re: [SlimDevices: Touch] Color Management of Scanned Album Art
I'm an absolute novice in photo editing , but do you produce the *.jpg picture in photoshop to ? I would export a jpeg copy and use that, it's the most compatible way to tag in LMS afaik . Mnyb's Profile: http://forums.slimdevices.com/member.php?userid=4143 View this thread: http://forums.slimdevices.com/showthread.php?t=95637 ___ Touch mailing list Touch@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/touch
Re: [SlimDevices: Touch] Color Management of Scanned Album Art
jdt7385 wrote: I am unable to achieve good color in album art that I have scanned and added to the music using either dbPoweramp or MP3tag. I scan the art from the CD cover and do modest editing in Photoshop. I use either Adobe RGB or Prophoto profiles. I have tried changing the color profile to sRGB (usually good for web work) and deleting the profile (no color management). No matter what I do the color in the photos in both the dbPoweramp and MP3tag programs and on the screen in Squeezebox are dark and lifeless. What should I do to correct this problem? I use Photoshop CS5. I will appreciate any help you are able to provide. Can you upload an example? kidstypike's Profile: http://forums.slimdevices.com/member.php?userid=10436 View this thread: http://forums.slimdevices.com/showthread.php?t=95637 ___ Touch mailing list Touch@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/touch
Re: [SlimDevices: Touch] Color Management of Scanned Album Art
Aha! Gamma rears it's head again. This all starts with the characteristics of CRT tubes. A CRT tube does not have a linear transfer function, if you double the input voltage the light on the screen does not double. The function of the curve traditionally uses the greek letter gamma, so this function has come to be called a gamma function. This all came to light (pun intended) in the early days of TV, the sensors used in the TV cameras were linear, the output voltage varied directly with the light intensity, but the CRT tubes used for display were NOT linear, so the images didn't look right. They fixed this by adding a gamma correction circuit in the TV camera that applied the inverse of the gamma function. Most people, even technical people in the industry had no clue about this gamma issue because the cameras corrected for it, no matter where you hooked up a CRT tube in the chain to look at the picture, it looked right. Fast forward 50 years to the start of computers being used for taking and displaying images, computers are still using CRT tubes to display things, but the early crop of scanners are linear devices, just like the sensors in the TV cameras, so an image scanned on one of these and displayed on a CRT tube, didn't look right. The professionals understood this and used software to apply the gamma correction so things looked right on the screen. But when amateurs came along they didn't have any clue about this and kept on getting images that didn't look right. It didn't take too long for the market to realize the problem, all the manufacturers started shipping scanners, and then digital cameras, with the gamma correction built in, so all the image files that came out of these devices were pre gamma corrected to display well on CRTs. For quite a while this worked well. Then LCD screens came along, unfortunately LCD screens are linear devices so now all these pre-gamma corrected images don't look right any more! The makers of LCD computer monitors realized this and added the gamma function in the monitor electronics before sending the data to the LCD pannel. So these days we have the sources taking the linear data from their sensors correcting for display on a CRT, the monitor then anti-corrects back to linear space for display on the LCD. So the task here is to find out whether the Touch already does the anti-gamma correction or not. And then find out whether you scanner applies the gamma correction or not. It seems like we have a mismatch here. To test the Touch, take an image that has a wide range of different shades from light to dark that displays well on your regular computer screen and use that as cover art for an album and see how it looks on the Touch. ( it can be something you take with a digital camera or something from the web, don't use the scanner at this point). If the Touch is doing the anti-gamma correction it should look fairly decent on the Touch screen. If the Touch is not doing the correction it will look light and washed out. Now try using your scanner on a real photograph, it should look good on your computer screen. Do NOT scan cover art, a magazine page or something printed on a computer printer. If it does look good the scanner is applying gamma correction. Then try using THIS image as cover art, Does it look good on the Touch? If its light and washed out, that means the Touch is not anti-correcting. If this looks good but scanned cover art does not look good we have a different issue. If it looks DARK and contrasty then the anti-correction is too much. If it's dark and washed out then there is something weird going on! Do the tests and report on the results and we can see what needs to be done. John S. JohnSwenson's Profile: http://forums.slimdevices.com/member.php?userid=5974 View this thread: http://forums.slimdevices.com/showthread.php?t=95637 ___ Touch mailing list Touch@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/touch
Re: [SlimDevices: Touch] Color Management of Scanned Album Art
See if you can find some of the same covers that you've scanned on http://www.albumartexchange.com. If there's a significant difference, then you're obviously doing something wrong. If not, I'd chalk it up to the cheap display on the Touch. JJZolx's Profile: http://forums.slimdevices.com/member.php?userid=10 View this thread: http://forums.slimdevices.com/showthread.php?t=95637 ___ Touch mailing list Touch@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/touch
