Understanding import duplicates

Software darktable
1

Hi everyone,

short off-topic block:

I made the switch from lightroom a few months ago, and I’m blown away by how awesome darktable is!
It has honestly been a great source of joy for me to work on understanding how the software and all the modules work. I’m lurking on this forum a lot, and watch a lot of videos by the many great content creators!

I wanted to use my first post on here also to say a big thank you to all collaborators on this great project and to all content creators who helped a lot making all this accessible for me!

Now about my issue:

(This is on the nightly windows build of DT, 4.5.0+1377~gca67684661)

I use the following naming scheme for importing my photos:
base directory: $(HOME)/photos/general
sub-directory: $(EXIF_YEAR)/$(EXIF_YEAR)-$(EXIF_MONTH)-$(EXIF_DAY)

I usually copy&import straight from my SD card, but I also did an initial copy&import from my local raw folder when i made the switch from lightroom.

Now today I took some photos using an SD card which already hat some photos on it, that were already previously imported (from disk, during my initial copy&import).

After my photo session the SD card had the following contents:
DSC_1871.NEF to DSC_2081.NEF (207 old photos, with some gaps in numbering)
DSC_6330.NEF to DSC_6378.NEF (new photos)

I copied & imported and had [x] select only new pictures selected. However all pictures were selected.
This created duplicates for the old photos, they got copied into the correct folders but were named
20231204_0001.NEF - 20231204_0207.NEF.

So trying to understand how this behaves I have the following questions:

  1. Where does this naming scheme come from? Is this a fallback as to not overwrite any images?
  2. Why were the images not detected as duplicates? Does it make a difference that I previously imported them from disk instead of straight from SD card?

EDIT: Regarding question 2: At one point I made a change to the timezone or time in my camera, could this have affected the hash values of the images?

Thank you for reading my post!
Paul

2

Welcome…

It could be that also you have this option…

image

To be honest I would have to go and try now to see if it will import a second time as duplicates without that selected… I didn’t think so… but your time change may make it appear as a new variant or duplicate…

1 Like
3

Thanks for your reply Todd,

I had that option checked, but it still selected all files on my SD card.

I did a MD-5 check, and the raws from the original import and the re-import are identical. However, curiously my windows explorer shows a different last modified time (differing by 40 minutes, which I think is what I changed on my camera.)

So maybe last modified time factors into duplicate detection too?

4

Normally I think you just see them checked if they have been imported and any new ones show as not yet checked…

I manually import all my photo’s and so the importing into DT is really just DT creating a database entry for the file location….