Why the huge file size in Photo AI?

Hi, I’m mostly working with files from the Z9, they’re raw files when I start in Lightroom Classic and are in the 30-40 MB range, when I use the Photo AI plug in, the .tif files that go to AI are in the 200MB range and then when they go back to LRC they’re in the 180-200MB range. why are they so large and how can I make them smaller? Im sure it’s something I’m doing. Thanks

Hi @danafo, are you using ZIP or LZW compression when saving your TIFFs? And are they 16-bit or 8-bit?

I have no idea, in LRC I click on edit in Photo AI, it imports it, i run autopilot, it sends it back to LRC. I’ve been doing it this way for z long time, I don’t remember it being this way previously.

@danafo I think the better way to process your pictures is to go through File > Plugin extras > Process with Photo AI. It creates dng files, which are raw and smaller in size. Using Edit with > … with any application will create relativelly large TIFF or PSD files.

They are not RAW files as RAW files hold camera sensor data. The DNG is a processed image with a profile and are usually the same size as a generated TIFF from the RAW input image.

I bought some software many years ago that does an extremely good job of reducing the file size of images. It still works–kind of. It reduces the number of colors down (imperceptible to the naked eye). Net effect is the resolution stays the same, but the file size gets much much smaller. Unfortunately I bought it back in the year 2000 or something many many years ago and now it has a hard time keeping up with much larger file sizes that we have today.

We need to ask Topaz to build this feature into photo AI and gigapixel AI! Specifically, we need a feature that would reduce the number of colors in an image so that it is imperceptible to the human eye and yet it would drastically reduce the file size after the resolution has been increased.

I’m sure this would be an much loved feature if they’d add this.

I have just started using PhotoAI (downloaded it today) and I can confirm that going through File > Plug-in Extras does produce huge files. I’m working with iPhone 14 Pro Max images captured with Lightroom Mobile. The original dng is 13.93 Mb, after running through PhotoAI (create new file option selected) with autopilot, the new file size is 69.95 Mb!

For reference, Lightroom’s new Denoise AI produces a 44.92Mb file.

What is going on to make such a huge increase?

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The second post in this thread gives advice on the options available.

Note that the DNGs produced in this process are NOT RAW files. But, unlike RAW, contain bit depth information, color information and a profile.

I just did a photo this way, through file, plug in extras, process with photo AI. After running Auto pilot and exporting back to LRC, it went from a 57mb Nef file to a 257mb DNG file :joy::joy::joy:

That’s less than 5 times bigger. You need to check by sending a TIFF, 16bit and no compression, and see how big that is.

You can always run it though Adobe DNG converter and compress the file.

I started just using the LRC denoise snd it’s working great with much smaller files at the end. I’ll only use Photo AI now on the rare occasion I want to sharpen up a photo

I just did a quick test. I took an original DNG image (iPhone 14 Pro Max captured with Lr mobile) and ran it through LR Denoise and through Topaz (everything at suggested values) and exported all three to full-size TIFF (16-bit, ProPhoto). Every one was exactly the same size - 65.1 Mb. The LR-denoised DNG is smaller than the Topaz-denoised DNG (50.9 vs 69.93 - larger than TIFFs because of a 3:2 crop of a 4:3 original).

It does mean that there’s some serious compression in the original since that only weighed in at 12.32 Mb.

The DNG files from phone is a RAW file.

RAW files created by cameras do not have the demosaicing process applied. The raw sensor data typically contains only luminance values for each pixel. (Single color per pixel)

When you convert a RAW file to DNG using Lightroom / TPA, the demosaicing process is applied during the conversion process. (RGB, Three colors per pixel)

That is why after demosaicing process, the file increase at least 3 times.

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@AiDon This is what Adobe writes about this format:
DNG means Digital Negative. It’s a type of raw file format used in digital photography, developed on the TIFF 6.0 format.

So is TIFF a RAW file format used by, for example, Canon’s CR2 format.

DNG can certainly be used as a container for RAW images as Pentax do. But in this format they are not RAW files but TIFF with a profile.

Just so you are clear on this, RAW files contain ONLY sensor data and a full size preview. And you cannot create a RAW from a DNG. The easiest way to test this is to use the Adobe DNG Converter to create a DNG from a RAW file you have, then change the DNG file extension to that of the input RAW and see if you can open it in the native RAW processor for the camera.

Please do not address me like this, I just wanted to help someone. And I only express what Adobe, Topaz, Skylum etc. communicate.
Adobe created DNG as a brand independent type of raw file. It contains (some sort of) raw data and it contains a full size JPEG. I’m not saying it is the same as camera raw.
I use Topaz JPEG to RAW AI: guess to what file formats it converts. In Denoise AI, I can apply the RAW model to a DNG file…
DNG files contain more data than only the picture (e.g. white balance, tint, tone, vibrance, dynamic range). These are considered raw data.
But it’s easy to confuse with proprietory raw.

RAW files contain ONLY sensor data and a full size preview

No, they include what vendors want them to include. Please look it up.
Your test of replacing .DNG by that of the input raw extension is wrong: they are structured differently, just as 3FR, NEF, ARW, CR3, FIF…
Most camera raw formats are based on TIFF.

Like what?

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