P: Normalize focal lengths to 35mm equivalent field of view (instead of "literal" EXIF values)

@dcooper7: "Does anyone know of a workaround that allows this information to be visible while editing in the Develop Module, without switching to the Library Module? Any plugins, external tools, or tweaks that could help?"

See here for how to edit LR's preference file to display the 35mm equivalent (when it's recorded in EXIF metadata by the camera -- many cameras don't):

https://community.adobe.com/t5/lightroom-classic-discussions/how-to-display-location-information-in-loupe-view/m-p/14375008#M353898

The internal identifier for that field is "com.adobe.focalLength35mm".

Hi everyone,

I’ve run into a workflow issue in Lightroom Classic, and I’m wondering if there’s a workaround—or if Adobe could consider adding a feature to address it.

Currently, Lightroom does not allow the 35mm equivalent focal length to be displayed in the Develop Module’s Info Overlay (pressing “I” to cycle through overlays). This information is already available in the Metadata Panel in the Library Module, but not in the Develop Module.

This means that every time I want to check the 35mm equivalent focal length, I have to:

1. Click over to the Library Module

2.Look at the Metadata Panel to find the 35mm equivalent focal length

3. Click back to the Develop Module to continue editing

This slows down my workflow significantly, especially when working with images from cameras where I frequently need to reference the 35mm equivalent focal length.

Feature Request:

It would be incredibly useful if Adobe could add an option to display the 35mm equivalent focal length in the Develop Module overlays, just like how we can already see focal length, shutter speed, ISO, and aperture.

Question:

Does anyone know of a workaround that allows this information to be visible while editing in the Develop Module, without switching to the Library Module? Any plugins, external tools, or tweaks that could help?

Thanks in advance!

Let me add my voice to this request 🙂

1. Yes, we all know the difference between physical focal length and 35 mm (or full frame) equivalent focal length, which is used as an indication for the field of view.
2. As mentioned previously (Jim Wilde), the equivalent focal lenght is already available in the metada fields.
3. Many photographers use various cameras, ranging from phones, drones, ... up to full frame or even bigger. Having the ability to filter through all of these would be great. Not to mention (much) older cameras which used to have smaller sensors. I'm not an expericed photohrapher nor am I a pro. And yet, my library contains a zoo of cameras and lenses:

    

4. Comparing field of fiew is usually more important or makes more sense than real focal length. Especially when shopping for a lens.
5. Could even make sense on full frame bodies when the crop mode is enabled. Images from the same body+lens combo would then be discernated, whereas they're not when you filter based on the focal length only.
6. Since the data is already available, adding this to the filter feature should be pretty easy

    

And if we want to enter that rabbit hole, we could also have the same for the aperture 🙂

Hi Johan:

"Why not? Your most used focal length is your most used focal length, regardless of whether you used it on a full frame camera or an APS-C camera."

Sorry if I wasn't clear enough. I meant my most used focal length in 35mm. If we speak about "real" focal length (nominal, literal, whatever we may want to call it)... then maybe my most used focal length is 10mm. But:

- A few of them were shot with my Sony RX100 (1" sensor) at 10mm (which is aprox. 28mm in 35mm)

- Many of them, with my Canon 5D Mk II at 10mm (=10 mm since it's a full frame camera)

- The rest of them, with a micro 4/3 camera at 10mm (which I think equals 20mm in 35mm)

Then, say I want to buy a lens for my APS-C camera - would it be a good idea to buy a 10mm lens, based on this data? (15mm or 16mm equivalent in 35mm, depending on the APS-C camera maker). It's the same focal length? Yes. But it will render a different angle of view if compared to any of the images I based my decision upon, which is what matters to most of us. Well, at least to me! 😅 Therefore my suggestion about being able to always work with 35mm equivalent values.

As for building a smart collection or filtering by Metadata, of course, that would be ideal. But again, if we are speaking in 35mm terms, I can't filter or make a Smart Collection if the 35mm equivalent data isn't there in the first place 😟 - like I said, this field isn't populated for all cameras. And even when it is there, I can't use the Metadata filter and filter by "Focal Length 35mm" unless I use a plugin (still, I can make a Smart Collection, but then again, the "Focal Length 35mm" data must be there already).

Hope I made myself clear, excuse me otherwise, since english is not my native language.

Have a great day!

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To build on previous discussion, not all cameras record the EXIF field Focal Length 35mm. My test catalog includes sample photos from 111 distinct camera models, and only 78 of them recorded the EXIF field Focal Length 35mm:

(It may be that some of those other 33 camera models may record Focal Length 35mm with other lenses than used in the catalog's sample photos -- I haven't investigated.)

It's a straightforward calculation to use other EXIF fields usually included by cameras to compute the effective 35mm focal length.  The Exiftool utility will do that calculation for you,  and its tag Composite:FocalLength35efl displays EXIF:FocalLength35mm if it was recorded by the camera, otherwise it will display the calculated value.  However, if the pixels in the photo have been cropped or resized, the calculated value will be wrong. (LR cropping won't affect the calculation, since it doesn't affect the pixels in the master photo.)

You can use the Any Filter plugin's Filter command to see the computed FocalLength35efl:

Unfortunately, it sorts the column by the actual focal length, not the effective 35mm focal length, due to the way Exiftool displays those values.

"For instance, how many of us would like to base their lens-buying decisions on their most used focal lengths? Me, for instance, but I can't because of this."

Why not? Your most used focal length is your most used focal length, regardless of whether you used it on a full frame camera or an APS-C camera. And if you specificly want to know what your most used focal length on your APS-C camera(s) is, then it is easy to set up a filter or create a smart collection for that.

Hey GoldingD,

Yes, the "Focal Lenght plugin" is already mentioned in my post.

As for lenstagger, not sure how it would help with this issue 🤔 🤔

Have a good one.

Perhaps:

http://regex.info/blog/lightroom-goodies/focal-length-sort

or:

https://www.lenstagger.com/documentation/how-to-use-lenstagger/

For Canon and Nikon I believe the situation is a bit more complex for the original DSLR models, as opposed to newer Mirrorless models, since the lens mount allowed the use of earlier lenses which did not have electronic contacts so the lens info could not be transmitted.
I am referring to lenses pre digital these lenses are full frame but can be used on ACP model cameras.

Just a thought.

Note: I have entirely rewritten my original text. I have realized my original explanation was a bit confusing, sorry about that.

Please upvote if you agree! Or provide your ideas about how to implement changes to correct this situation, because even if this "35mm Focal Length" field was force-populated somehow, it still wouldn't appear everywhere where it is needed (e.g. under the histogram, etc.).

So, while I think this is a very simple matter (it's just a multiplication, assuming that LR knows the crop factors for each camera), I think it requires some redesign in the way Lightroom Classic handles focal length values.

Thank you so much!