Tiff files, some small, some huge

joey1211

joey1211

joey1211

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I have received some tiff files which have been exported from Sibelius (a music manuscript creator). Photoshop reports them as being A4, 1200dpi bitmaps. The file size is half a megabyte.

Converting some pdfs into tiffs using the same sizes as above gives me a file size of 10MB+

Anyone know a reson for this? My tiff files are usually massive and use a lot of disk-space and processing time when working with them. Being able to drop them to 1/2MB would be fantastic.
 
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They'll just be compressed TIFFs, almost certainly using the LZW compression also used by GIFs.

The compression ratio you're seeing with the Sibelius images is due to the algorithm that this LZW compression uses. Without going into details - but hopefully not being patronising! - any image that's predominantly one 'page' colour spotted with just one other colour will give this impressive compression. Like musical scores, of course.

If your big TIFFs have more complex colour information - gradients, photos, that sort of thing - then the compression will be much less effective [though you can use JPEG compression, but that's lossy, so not really recommended].

Note, also, that both the Sibelius TIFFs and the ones you make at the same size/resolution will occupy exactly the same amount of memory when opened [i.e. when uncompressed]. This is assuming they're using the same colour model of course [e.g. RGB, or CMYK].
 
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Fantastic. I thought that tiffs were always uncompressed. No compression gives 17MB; LZW 7MB and zip 335KB!

So, this is also the reason that my pdf files were always much smaller than the combined tiff file sizes, even though Distiller was not compressing the image.

I'll now need to find something else to fill my hard drive with.
 
Yup, though PDFs use more cunning compression techniques - like keeping fonts as separate vector data - to achieve their relatively miniscule file sizes.

If you're determined to fill that drive, take a screenshot of the folder showing how much space you've saved with compression, convert it to a 16-bit-per-channel CMYK uncompressed TIFF file and resample/upsize it to the dimensions of a full-size advertising billboard. That ought to do it :D
 
is it bittonal images? If so, you'll get better (and more compatible) compression using CCITT Group4 compression, or even better still JBIG2.
 
Straight over my head...

I use tiffs purely for black on white purposes, i.e text. Never use them for anything else. I prefer to OCR scan usually but sometimes a straight black & white scan has to be done. For this job it was music manuscripts. 2-3 times a month I still scan in paste-ups for local newspapers. Painful!
 
We leave text in a tiff at 1200dpi to keep the crispness.

The next step is to get it past out pre-press monkey who insists that tiffs are left uncompressed. But when jobs start taking up 2-3GB, I knew something was wrong.
 
joey1211 said:
We leave text in a tiff at 1200dpi to keep the crispness.

The next step is to get it past out pre-press monkey who insists that tiffs are left uncompressed. But when jobs start taking up 2-3GB, I knew something was wrong.
Click to expand...

Sorry, just noticed it was 1200dpi, in that case it will be very large. it's a 16x increase in size, but G4 compression should be even more efficient as it's essentialy a RLE type compression.

Uncompressed will be very large indeed.
 
You may get around the issue by going back to Sibelius and exporting as EPS (encapsulated postscript) - not sure on the prog, but this will essentially be a vector output which give maximum quality and smaller compatible file size - your Printer should be able to do EPS.
 
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