P: AI Denoise output to TIFF option vs DNG

Ok you started with a DNG.  I'm starting with a RAW file.  xxxx.ARW right out of the Sony camera.

No explanation of how the TIFF was created. 

Take the Enhanced DNG, into Photoshop. Hit File/Save as...  Select TIFF and no compression, the result will be back close to the original raw.  I'm on a Mac using lates PS & LR. 

@m cs16279208 

I don't know where you get those numbers. Here's a file from an a7r V:

Note that the enhanced DNG is almost exactly 4x the file size - that's R + G + B + original mosaic.

@Jao vdL and others: If you take a 50mb RAW Sony file, run it thru AI Denoise, the resulting DNG is over 200mb.  Take that 200mb file into PS and then save as TIFF and the file is reduced to 57mb.  I've done this numerous times with the same results. So the resulting TIFF is definitely NOT "about the same size" as the DNG and it also retains the applied denoise without the bulk. 

I shoot sports professionally and have for many years. The overwhelming bulk of my work is produced under lighting that requies ISO 12,800 and higher. Typical output per match for the client is 150 files. I'm well versed in what my client's expectations are regarding quality. The standard (manual sliders) LR denoise capabilities are IMO marginal at best. There are third party applications that perform significantly better which I have been using.  With the introduction of AI Denoise, LR's denoise quality has greatly improved but at the same time it introduced compromises. The biggest is file size & right behind it is processing time. I won't even get started on the file renaming which Adobe doesn't provide a way to modify, sheesh - really Adobe? This thread was started to point out the need for an option in AI Denoise to output a file that doesn't retain the 3 color channels and eliminates the accompanied RAW. The process I just related does this but it requires multiple steps which can all be done internally if Adobe adds the programing necessary for the option in the AI Denoise panel.

@D Fosse I never mention anything about TIFF being better.  Maybe you should re-read my posts.  Also run with a 26TB NAS but still dislike having 200mb files. They may be ok for others but not for me.

@D Fosse @Is exactly right. A tiff is going to be about the same size (typically around 150 MB) and you make some really extreme compromises on quality for basically no gain in file size. Even worse if you want smaller size your only option is to go to 8bit which really drastically lowers the quality and editability.
you really only should be doing this to one or two images out of a shoot. The gain in quality on a 50MP image is only noticeable in prints that are 6 foot wide. This is not something you should do on all your images. Only on the real winners that you are going to print humongously large. There just is no point if what you do is share images online with clients. You're far better off using the standard sharpening and denoising tools. Also as said, storage is trivially cheap nowadays but really you're wasting your time if you run all your images through AI denoise.

@mschlotz  - I still don't understand why you think TIFF is any better? A Denoised DNG and a TIFF will be roughly the same size, simply because they are RGB files. It's going from a single channel at 14 bit depth, to three channels at 16 bit depth, that causes the size increase.

In other words, no advantages, plenty of  disadvantages. A linear DNG still gives you a lot more dynamic range to work with.

And you're not going to like what I say next. Here goes: if you worry about file sizes, you're in the wrong business. There. Image files will eat disk space for breakfast. You have to have expansion plans for what to do when (not if!) your disks fill up. I recently bought two 18 TB disks just to keep up. On the plus side, I don't get disk failure - I replace them before they have time to fail.

Another question is if we can strip the RAW out of the resultant DNG, then what size would the DNG be.

And as for future proof, or future mods. No, many of us are perfectly happy to start from scratch. After all, is not the process for most to create the AI Denoise DNG from the unedited RAw, then work on the DNG, not work on the RAW, then create the AI Denoise DNG.

Jao, I do understand the how's and why's of the process Adobe is using. The bottom line is the second paragraph in my last reply above. The space the DNG takes up is too much. The time and effort to get around the issue by manually creating the tiff, having to import it back to LR and then delete the dng is too consuming. An optional process is needed to take the dng and do what save-as tiff does in PS, then send it back to LR. 

The size increase is inherent to it being a demosaiced image. A tiff is going to be similar size except if you lower the bit depth (which you don't want to do). Your Sony A1 for example is a 50 MP camera. Demosaiced to a 16 bit tiff, that 50 MP image balloons to 300 Mbytes of data (50 times 3 color channels times 2 for the 16 bit depth), which compressed goes to 150 to 200 Mbytes of data just to do a tiff from it. Raw files are so efficient because they only store one color channel per pixel and typically only store 12 bits of data which demosaiced formats can't do. Anytime you demosaic the data, your file size will balloon therefore. The AI Denoise essentially does a demosaic of the raw data and therefore the ~200 Mbyte filesize (especially since it includes the original raw which is weird since you still have that in your catalog but hey) is exactly what you would get if you went to tiff but you retain much better editability.

For you if you want to save some space, you can convert the resulting dng files to lossy compressed dng. This can gain you another factor of 2 with minimal loss of quality.