Vuescan: TIFF vs. JPEG

[drjoke]

I just started trying TIFF recently and am shocked by how difference the quality is.

Could this be due to the fact that TIFF can support more bits per pixel whereas JPEG is only 8? I have Coolscan V ED, which advertises 14 bits per pixel.

There is no bits per pixel setting in Vuescan, but can I safely assume that it is using 14 bits per pixel when I am scanning as TIFF?

 

[Ronald_H]

There IS a bits per pixel setting in Vuescan for TIFF, under 'output' ...

TIFF's can be 8 or 16 bits (even 1 if you would so desire), jpegs are always 8. If you can see a major difference, you are doing something wrong. Is it possible that your jpeg compression (or maybe size reduction) is set far too high?

16 bits does NOT give you better quality per se, it only gives you more latitude for adjustment. Basically you can do more color adjustment without posterization, and you have more shadow and highlight detail. A freshly scanned TIFF or JPEG should look the same on your monitor, because that device will basically only display 8 of the 16 bits available. Only if you are starting to do adjustments, you will see you can do so much more with a TIFF.

Here is an example (the original file is a digital NEF from a Nikon D70, but the principle is exactly the same, more bits is more latitude).

What the original jpeg looks like:

What the edited .nef looks like

Now try to adjust the jpeg to look like the image converted from a NEF...

Hope this clarifies things.

 

[infrequent]

btw, lovely shot.

 

[hans voralberg]

TIFF has way more latitude to play with, but then the scanning time is madness =) I just stick with Jpeg with minimal compression

 

[drjoke]

Check out how much detail I can recover using TIFF and Coolscan V ED. The Film is Velvia 100.