Huge files with CS4

[PeterAit]

I am using LR2 and CS4. From LR, I view a 10 megapixel raw file (NEF) and then open it as a SmartObject in CS4. I make no changes to the image in CS4 but just save it. The resulting TIFF file is 20 times as large as the original RAW file - 189 MB vs 9 MB. What gives? Why does the TIFF need to be so huge?

Thanks,

Peter

[Farmer]

I am using LR2 and CS4. From LR, I view a 10 megapixel raw file (NEF) and then open it as a SmartObject in CS4. I make no changes to the image in CS4 but just save it. The resulting TIFF file is 20 times as large as the original RAW file - 189 MB vs 9 MB. What gives? Why does the TIFF need to be so huge?

Thanks,

Peter

It's because it's an SO and you're saving the TIFF with layers.  Do you have a specific need to save it as an SO and therefore with layers?  If not, then don't save the layers and just save it as a regular TIFF.  If you need it to stay as an SO I would suggest PSD.

Even without SO, a TIFF for a 12.2MP camera (which is what I have) is about 71MB in 16bit (half that in 8bit of course).  That's perfectly normal.