TIF file compression in Capture One

[roydonian]

Advertisement (gone after registration)

I'm puzzled by the size of the output files created by Capture One 12 and 20.

A DNG from my Leica M-D camera is about 25-30Mb in size.

If I select 8-bit TIF as the Capture One output format, the resulting file size is a massive 68Mb. That size remains unchanged irrespective of whether I opt for compressed TIF or uncompressed TIF as the output format.

A JPEG with a quality setting of 100 is about 20Mb in size, dropping to around 6Mb for a quality of 90, or 3Mb for a quality of 80. So in this case, I do have some control over the size of the resulting file.

The DNG, TIF and JPG files all have the same dimensions in terms of pixels.

So I'm guessing that in the case of the TIFs, perhaps there is some additional action or setting that must be applied in order to get the compression to take effect. Perhaps I need to turn my chosen setting into a stored 'Recipe'.

If I process the same pics in RawTherapee, the uncompressed TIF is 70Mb, and the compressed is 36Mb.

[zeitz]

.dng contains no image.  In a .dng file there is the pixel readout matrix (raw data of the sensor), metadata and editing steps after you work on the .dng file with a nondestructive post processing app.  You only see an image because the raw converter you use shows you an image.  .tif is an actual raster scan image with metadata; editing steps can be reversed if you use layers.  .tif can be "compressed" by two methods, but both are lossless compression.  Compressed .tif is very different from compressed .jpg which is lossy.

Remember .dng is not an image file; it is a file of information from which an image can be made.