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You are here: Home / GFX 100 / Fujifilm G lenses hotspotting at 720 nm

Fujifilm G lenses hotspotting at 720 nm

April 8, 2021 JimK 14 Comments

I keep being asked which Fuji G lenses hotspot and which don’t. I tested on a GFX 50R modified by LifePixel to respond to wavelengths longer than 720 nm. Here’s a table I made from the results:

OK means no hotspotting, or very little. H means hotspotting that I consider to be unacceptable. I threw the Coastal Optical 60 mm f/4 UV-VIS-IR into the mix. All lenses were tested with subjects tens of meters away. The second row is the f-stop.

 

GFX 100, GFX 100S, GFX 50S

← Smallrig GFX 100S L-bracket Shutter shock in the GFX 100s →

Comments

  1. Josh Himes says

    April 8, 2021 at 7:02 pm

    Thanks for compiling this chart Jim! I can add that at 850nm the 120 has the same level of excellent hotspot performance as the 45 and 250. If there is a specific test you are doing, let me know and I can send you a few samples for evaluation.

    Reply
  2. Gene K says

    April 9, 2021 at 10:32 am

    Jim:

    Could you define what you mean by hotspotting.

    Reply
    • JimK says

      April 9, 2021 at 12:23 pm

      https://kolarivision.com/the-science-of-infrared-hotspots/

      Reply
  3. Jason K says

    April 25, 2021 at 9:55 pm

    Have you considered a more technical approach to quantifying hotspot tests? I find trying to shoot into foliage or a wall like many do to be a pretty poor method- you really need a strong Ir source in bottom frame and then something empty and clear in the middle- like clear sky in order to see more subtle contrast issues.

    Or to quantify it this is the best testing method anyone has come up with as a system so far: https://www.edwardnoble.com/hotspot-info

    https://www.edwardnoble.com/hotspots

    I have replicated this test myself with a similar lamp and testing scale since I can’t trust any other hotspot lists or people.

    I’ve lost count of how many times some list or person has sworn lenses don’t have hotspots only to buy them and find they’re terrible (the lifepixel list, kolari list, countless blogs and forums). It seems few really knows how to stress test lenses and find the more subtle hotspot issues, but they can ruin photos.

    I would be interested in moving to Fuji for IR, but lenses do not seem promising. It’s also interesting that fuji releases an IR GFX camera, but doesn’t look like they have put any special thought into IR lens performance for it.

    Reply
  4. Phil Lindsay says

    April 30, 2021 at 10:02 am

    My testing shows that the both the Fuji 45-100 and 100-200 Zooms perform well (no hot spots) in with 680 and 720 nm IR filtration on the 50S. Unfortunately the 32-64 Zoom does not do so well beyond f/8. The 100-200 Zoom is also good with 850 and 950nm filtrationPhil

    Reply
    • Irven says

      February 25, 2022 at 7:29 pm

      Thank you for the thumbs up on the GF 100-200. Can’t wait to use it on my soon to be converted GFX 50R.

      Reply
  5. Josh Himes says

    May 3, 2021 at 9:03 pm

    Hi Jim,

    Just curious if you have had time to test the GF 80 on your IR converted camera yet?

    Reply
    • JimK says

      May 3, 2021 at 9:08 pm

      I haven’t tried it, but I will.

      Reply
  6. Josh Himes says

    May 3, 2021 at 9:22 pm

    Thanks in advance. I am hopeful that it will be a good performer in IR.

    Reply
    • JimK says

      May 4, 2021 at 9:00 am

      Tested. It works fine. There is some measurable hotspotting, but nothing that would be objectionable unless you’re really pushing it. I’ve updated the table.

      Reply
  7. Josh Himes says

    May 4, 2021 at 12:14 pm

    That’s good news! Thanks for testing!

    Reply
  8. MARK SILVER says

    February 19, 2022 at 9:30 pm

    How confident are you that the GF 45-100 performing well?
    I just acquired the 45-100, and am considering selling my 45 mm prime since I have the new lens.
    Thanks

    Reply
    • JimK says

      February 20, 2022 at 6:30 am

      My copy appears to be excellent.

      Reply
  9. Rob Shea says

    April 2, 2022 at 7:21 pm

    Has anyone tried the GF35-70mm in IR?

    Reply

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