Photoshop back to Lightroom, TIF filesize is very large

[steveisa054]

Hi! I'm looking for "how to do this in the best manner", and I am not sure if this post belongs in the Photoshop or the Lightroom forums. I will try Photoshop. I am working with photos from a Nikon D810, with about 37 million pixels. A photo processing workflow that I often use is to do global changes to a photo in Lightroom, then right click the photo and Edit in Photoshop. After I am finished editing in Photoshop, I save and close the file, and I am then back in Lightroom, and the photo I just modified in Photoshop is added to my catalog as a *.tif file. What I am noticing lately is that this TIF file is huge. My starting DNG file might be 37 MB but my TIF file is 3 to 4 times that size. It takes 4-5 photos to fill a Gigabyte. When I export my finished photo to JPG, it is usually ok with me to scale it down to 50%. 

Can someone give me a tip on how to modify this workflow so that I can somehow reduce the size of the intermediate TIF files in a good way?

Thanks!

[D Fosse]

A raw file is grayscale, one single channel, at 14-bit depth.

An RGB file from Photoshop is three channels at 16-bit depth (or 15+1 bit if you want to split hairs).

So that alone more than triples the file size.

Jpeg is another story altogether. It uses very aggressive lossy compression to reduce file size. The price is slight degradation every time the file is resaved.

[steveisa054]

Hi D_Fosse, yes, I know the math. The increase in file size is understandable. But what do most people do? Do they convert the TIF back to 8 bit depth before returning to Lightroom? Or do they continue to support the file storage industry?

The DNG file is only around 36MB so I guess that is telling me that the DNG is based on 8 bit depth. Going into Photoshop for doing one little minor edit and back to Lightroom then puts the file in 16 bit depth, with a huge increase in size. I am just looking for best practice, what do others do in this case?

[D Fosse]

File size is what it is. Please don't be offended when I say this, because it's nothing personal, just reality: if you worry about file sizes, you're in the wrong business.

I have 20 terabytes of disks in this machine, another 20 terabytes in my work machine, and several 8 or 10 terabyte externals used for backup and transport between them. Sizes aren't my biggest problem. Organizing and keeping on top of the number of individual files is. It wouldn't matter if they were smaller.

And even so, most of my money go elsewhere, not to the file storage industry. Disks are cheap.

[Derek Cross]

I find for most workflows, that at compression 8 to 10, JPG is "good enough" for a final output format, (though I would normally Place a native PSD file in an InDesign document).

JPG has the virtue of being economical in size (which can be important) , can be read by most applications used by others, can be accepted by photo printing companies and can be read by browsers.

[steveisa054]

Perhaps I should say that I am not a professional photographer. As a hobby, I take a great deal of photos of social dancing, and my end product in most cases is a JPG file that I upload to social media. On rare occasions I am asked for a better quality file, but then in most cases, the full sized JPG file is good enough. I do not want to delete the intermediate TIF files. But if I put 1/3 to 1/2 of the photos that I shot into Photoshop, causing an increase in file size from 38MG to 38MG + 150-200MB, this all adds up. If this was my profession, then I would be purchasing huge amounts of storage and accepting it, but it is a hobby for me. 

If I start with around a 37MB DNG file in Lightroom and do nothing at all in Photoshop, I wind up exporting the DNG as JPG. If I go into Photoshop for something, I wind up exporting the 16 bit TIF into JPG. What would I be losing, if I changed the mode of the finished photoshop image to 8bit before saving it back to Lightroom?