Generic maker notes set for use with analog data

[Leppo]

Hi,

I'm using a bunch of scripts to add Exif data to my scanned analog pictures.
As I cannot care less about the scanner maker notes, I wonder, if there is a generic set for maker notes I can use as replacement (and eventually derive a generic analog set from it, which covers film specific tags like film maker, type, developer + type of development, etc. besides the typical camera + lens model tags and stuff).

F.e. can you just derive a class Canon Maker Notes and extend it?
What needs to be done to stay compatible with HEAD branch development?
I need a quick dive into the main issues to get my head around.

When I think of the missing movements tags for tilt + shift, it makes sense to split and group off-specification tags (e.g. film, development, T/S movements, adapters). How can it be hooked/added non-destructively?

Thanks,
Leppo.

[Phil Harvey]

Hi Leppo,

The maker notes are not extensible.  ExifTool will not create new makernote tags.  The best you can do is to copy the makernotes as a block from an existing image, then modify them afterwards.  See FAQ 8 for some notes about this.

For extensibility, your best option is probably XMP.

- Phil

[Leppo]

Thanks Phil,

got it.
So, would you recommend to erase the binary maker notes from my scans generally, then?

For my purpose of course I overwrite make and model tags of my scans to store information about the analog gear and to be able to display it.
So far I did not suffer from corruptions, I just see some warnings here and there that maker notes cannot be parsed. I count this on the robustness of exiftool. Thanks for that.

The below is what usually gets written to a file from film:

        /usr/bin/exiftool -m -P \
            -DateCreated= \
            -DateTimeOriginal="$S_DATETIMEORIGINAL" \
            -Copyright="$S_COPYRIGHT" \
            -Make="$S_MAKE" \
            -Model="$S_MODEL" \
            -SerialNumber="$S_SERIALNUMBER" \
            -Lens="$S_LENS" \
            -LensMake="$S_LENSMAKE" \
            -LensModel="$S_LENSMODEL" \
            -LensSerialNumber="$S_LENSSN" \
            -MaxAperture#="$N_MAXAPERTURE" \
            -MinAperture#="$N_MINAPERTURE" \
            -ExposureCompensation="$(echo $S_EXPOSURECOMPENSATION | sed 's/[\ EV]//g')" \
            -ExposureTime="$S_EXPOSURETIME" \
            -FNumber="$S_FNUMBER" \
            -FocalLength="$S_FOCALLENGTH" \
            -ISO="$S_ISO" \
            -UserComment="$IMGCOMMENT" \
            -Caption-Abstract="$S_CAPTION" \
            -Sub-location="$S_SUBLOCATION" \
            -City="$S_CITY" \
            -Country-PrimaryLocationName="$S_COUNTRYNAME" \
            -ImageDescription="$IMGDESCRIPTION" \
            $FILE

New workflow then is a) erase maker notes, b) write analog gear exif data.
And for the rest I have to dive through XMP and develop a schema.
Right?

Thanks,
Leppo.

[Phil Harvey]

Hi Leppo,

Sounds good to me.

- Phil