Problem printing with 16 bit TIFF (Frontier)

[jimlp]

I saved some RAW files as 16 bit TIFF's today and brought them to my usual lab and I was told that they would have to be converted back to 8 bit to print them because the Frontier system would not recognize the files. This lab's Frontier system is state of the art and about 6 months old and the owner is fanatical about having the most up to date upgrades as well. He had me sit with him while he tried to bring my photos into the system to prove that he wasn't lying ( I knew he wasn't). Has anyone else had this problem printing 16 bit TIFFS/files? Could the TIFF format be the problem? I figured a TIFF is a TIFF but I think the 16 bit files may be cded differently.

[Jesper]

Just convert the files to 8 bit and send them the files again.

The Frontier, just like almost any other printer, monitor or other device capable of printing or displaying images, uses only 8 bits per channel. The main advantage of 16 bit is not that your images will look better, but that you have more data to use if you're post processing (which means, for example, that you won't see posterisation if you're stretching the contrast of the image in Photoshop).

[lostdoggy]

16 bit TIFF is only recognized by a few Softwares. Most Labs can't handle them because they lack the Gamut of colors. Its best to ask what the lab takes before bring it to them. You should be very glad that the lab is so nowledgable and honest. You can try Mpix online and see if they can take TIFF 16. TIFF 16 is not the same as TIFF 8. You can do a search on this site on TIFF some one explained before but I can't remember the exact language. Getting too OLD.

[jimlp]

Just convert the files to 8 bit and send them the files again.

The Frontier, just like almost any other printer, monitor or other device capable of printing or displaying images, uses only 8 bits per channel. The main advantage of 16 bit is not that your images will look better, but that you have more data to use if you're post processing (which means, for example, that you won't see posterisation if you're stretching the contrast of the image in Photoshop).

Thanks for the info. I thought that the difference would be noticable as the larger file size would mean more info in the file (highlights or gradations). If the sensor is recording a 12 bit file and you open it as an 8 bit aren't you throwing away information?

[unners]

Thanks for the info. I thought that the difference would be noticable as the larger file size would mean more info in the file (highlights or gradations). If the sensor is recording a 12 bit file and you open it as an 8 bit aren't you throwing away information?

yes you are. when printing, an 8 bit tiff will be as good as a 16 bit tiff. provided the compression is low, i doubt you would notice any difference from a jpeg either. as stated before, the extra info is helpful for any editing that is done. also i guess, its possible we might see 12bit printers in the future :)

[Jesper]

Indeed you do throw away information when you convert from 16 or 12 to 8 bits per channel. With 12 bits per channel, you have 2^12 = 4096 possible shades in that channel; with 8 bits, you have only 2^8 = 256 possible shades.

However, the human eye can't distinguish more than a few hundred shades of a certain colour between black and maximum saturation, and your monitor doesn't display more than 8 bits per channel, so it's not possible to see the difference between a 12 bit and 8 bit image on your monitor, neither on a print.

More bits per channel is useful when editing, however. Suppose you have a 12 bit photo that is underexposed. You want to make it brighter, so you use for example Curves in Photoshop. What that effectively does is stretch out the pixel values; it more or less multiplies the values by a factor. If the original values are spaced more finely, as is the case in a 12 bit photo, the values in the resulting image will also be spaced more finely. If it were an 8 bit photo, the stretched values will have larger "holes" in between, and if the steps become too large, you will see it as banding or posterisation. You can also see it on the histogram, which will have a characteristic look if the levels are stretched too much.

From Luminous Landscape (http://www.luminous-landscape.com/tutorials/bit-depth.shtml):

The key advantage of using a high bit image is that when you apply a Levels or Curves adjustment in Photoshop you are doing so to much more data than when you work on a low bit image. Changing the tonal range of a high bit file that has 65,536 levels Vs. a low bit file with only 256 levels means that when the data is compressed or stretched by using Levels or Curves there is more data to work with. A low bit image simply leaves gaps (the toothcomb effect as seen below) and this leads to posterization. Posterization manifests itself as abrupt jumps in colour or brightness level.

[mwinog2777]

8 or 12 won't make a bit of difference when you print. Test it out yourself on a home printer of good quality.