Why is Photo AI increasing the file size so much?

[michaelninos (MichaelN)]

[jo.vo]

This only occurs with RAW files and has something to do with compression. Your original file is compressed RAW whereas TPAI AFAIK cannot use compression in RAW photos due to copyright issues.

[AiDon]

See this post from support in another thread, btw if you search the forum you will probably find an answer. Nothing to do with RAW files or compression of them … it’s to do with Adobe and DNG:

Processing raw files results in very large dng files

The DNG output file size is expected behavior. The original RAW file is likely compressed while our DNG export is full size and uncompressed so the output file is larger. We do not have access to a DNG compression algorithm as that is proprietary to Adobe. If you need to decrease the DNG file size, use Adobe DNG Converter to compress the DNG file to a smaller size.

[tim.he]

Thanks for linking this!

[DaveL]

Appreciate that it isn’t your question, but of course it’s also to do with Nikon, who allow some lossy compression options in their RAW file formats.

Recompressing an already lossy compressed file (if it’s one of them) might lose more data if it were possible, but I don’t know if “preserve input format” will save it as the original NEF as I only deal with native DNGs from my cameras.

[tim.he]

A raw file will save as a DNG when it’s set to preserve input format.

[jo.vo]

Well, DNG is a container mainly used for RAW files and Topaz does not have compression for them due to copyright issues with Adobe.
So the above answer still is mostly correct.

[AiDon]

DNG is not a widely used container for RAW files, some cameras and cameras use it as it is TIFF based which is the major container for RAW.

The major use for DNGs is an archive format for RAW but they are not RAW files as they are converted RAW. Lately they have been used for processing because the advantage over TIFF is that they can have a camera profile attached.

RAW files contain ONLY camera sensor data and a JPEG preview. RAW files need to be processed into an image file before using.

[jo.vo]

For professional cameras this might be true but Phone cameras, especially iPhone do use DNG as a container for RAW photos.

And now if you think of how many photos are taken with mobile phones I’d question the „is not commonly used“ phrase.

Add to that that those mobile phone images do need the AI enhancement much more than a real camera.

Anyways, the large file sizes come from the ‚raw‘ data in those DNGs that was compressed before editing with TPAI but isn’t afterwards.

[ocarrasque]

Guys, my problem is the opposite. When I save in DNG the file has dimensions of 256x170px but the size is normal for this type of file. I can’t preview images saved in DNG unlike other denoise apps. Someone can help me?

[alanhusband-677420]

The 256x170 pixel dimension will be for the embedded thumbnail in the DNG. How are you trying to preview the images now? DNG support can vary quite a bit from program to program.