jpg quality after keyword and lightroom

If I add key words or add a collection and the metadeta is eddited on a jpg picture. Does the quality degrade. I know everytime you open a jpg file and then resave it (if eddited) then there is a slight degredation as it is a lossless file format. If i add a key word to a jpg, does that then "resave that file" and compress even more.

Can i convert a jpg to .dng format and then it does not become lossless or is .dng only for raw files?

It does not degrade the quality.

Yes you can convert the jpegs to DNG, but since LR does non-destructive edits it really doen't matter, especially since both file formats are handled the same way with regards to edits.

No, the keywording will either be saved in Lightrooms database or an external XML file depending on how you've set LR up.

Anke wrote in post #3326053
No, the keywording will either be saved in Lightrooms database or an external XML file depending on how you've set LR up.

Only for RAW files. All others will have the edits written directly to the file (JPEG, DNG, TIFF, PSD).

In2Photos wrote in post #3326066
Only for RAW files. All others will have the edits written directly to the file (JPEG, DNG, TIFF, PSD).

Either way, as In2Photos said, it does not degrade quality... that metadata is put before or after image data ( I can't remember which) and the pixel data is shifted (unchanged) accordingly... no recompression of the image data.

In2Photos wrote in post #3326066
Only for RAW files. All others will have the edits written directly to the file (JPEG, DNG, TIFF, PSD).

Blimey, I stand corrected, I thought it was for all

Anke wrote in post #3326224
Blimey, I stand corrected, I thought it was for all

I did as well. I just got Kelby's book and this is in the second chapter. I was a bit shocked.

bphillips330 wrote in post #3326034
If I add key words or add a collection and the metadeta is eddited on a jpg picture. Does the quality degrade. I know everytime you open a jpg file and then resave it (if eddited) then there is a slight degredation as it is a lossless file format. If i add a key word to a jpg, does that then "resave that file" and compress even more.

Did you mean lossy file format?

Anyway, provided you're editting the EXIF information and not image data, there will be no loss in image quality.

Sure you can, but you've already lost information in going to jpg in the first place. It just means that subsequent edits will not lose you more data.