lighttable image filtering

Software
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To resume this (slightly old) discussion about lighttable filters, I’m having trouble with filtering by focal length - specifically, by a focal length range.

I tried to filter for the range 100mm to 135mm, but AFAIK the right-click doesn’t permit range selection. However, the click and drag range offers a HUGE range (right up to 500,000mm and more! :astonished:). This means that the range is not ‘fine’ enough to permit selection of the required range.

Here is a screenshot, to illustrate the problem:-

image
image422×185 22.9 KB

Am I missing something obvious? Is there a setting through which I could adjust the widget for finer control?

TIA.

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Hi, I guess this is not exactly what you expect, but you could filter the collection using an and combination of focal length filters such as:

Capture d’écran du 2025-11-25 11-03-29
Capture d’écran du 2025-11-25 11-03-29493×289 16.6 KB

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Thanks for this. You’re right that it isn’t the solution that I’d expected :slightly_smiling_face:, but it will (hopefully) be a work-around. :clap: :+1:

I’ll try it out.

4

Ok… problem solved! I discovered a rogue image in the library, in which the EXIF showed (incorrectly, of course!!) that the focal length was more than 594,000mm. Obviously some kind of corruption there. :thinking:

I removed that image from the library, and after re-starting DT, the maximum focal length in the range had been reduced to a more-sensible 300mm.

In short: the corrupted image had caused the library to accommodate a ridiculously large focal length range. I’ve never encountered a lens with a focal length of 594,000mm. :grinning:

Hopefully, this thread will provide some help to anyone who has had the same problem.

Thanks for your help, nonetheless.

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5

Don’t try hand holding that lens if you do find it. :slightly_smiling_face:

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The James Webb telescope? :rofl:

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Image Stabilisation should take care of it, up to a few seconds exposure time! :scream:

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I think the focal length of the Webb is around 131.4 kmm or 131.4 m. Enough to image the oldest galaxies in the visible universe!

I was fortunate to play a very small role in the project; my team grew Si crystalline layers for an IR-detector.

My manager thought it was ironic that Webb (me) worked on the Webb telescope. :wink:

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Nice to see the project named after you. The humble worker rarely gets recognised. :slightly_smiling_face:

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