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Dive light recommendation - daytime, small, warm spectrum

Discussion in 'Basic Scuba Discussions' started by Aloha Joe, May 30, 2020.

  1. Diving Dubai

    Diving Dubai Instructor, Scuba

    # of Dives: 1,000 - 2,499
    Location: Dubai UAE
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    There is always a lot of misunderstanding with CCT (colour Temperature, and CRI) with regard to LED lights. This might give some insight

    Colour temp is the apparent colour of the light, CRi is a measure of the colour spectrum - a picture grabbed off Wiki highlights the spectrum difference between an incandescent lamp (full spectrum) and a fluorescent which is missing parts of the spectrum

    upload_2020-7-15_14-7-55.png

    Most LED lights including even expensive dive lights are quite rudimentary (with their light outputs) Remember the digital sensor on a camera (or film emulsion) "sees" colours differently to our eyes

    In the TV lighting industry (my job) we've been using LED lights since 2010 when they first became good enough. We've moved away from CRI as a measurement and over to TLCI (television lighting consistency index) because that's more relevant to camera's. The higher the TLCI - the less colourisation work in post. There are only 2 manufacturers (both European) that make high TLCI units (98-99%). We have to be able achieve High TLCI at any given Colour temp.

    Simply put. if you put a red colour filter in from of a tungsten light, the light from an LED light set to red and at 3400 CCT would appear exactly the same to the camera.

    We use variable white light (variwhite) so we can adjust CCT from around 2500K upto 8500K to allow them to be used in any circumstances

    To do this we will have 2 different dedicated arrays. 1 warm white, and 1 cool white,. mixing these together allows us to get the complete CCT range.

    But this is only half the story.

    LED's have lots of missing colour spectrums

    So as well as the 2 white arrays, we have an additional 5 other dedicated colour arrays. Red, Blue, Green, Lime Green and Amber - Green is the weakest frequency for LED hence two.

    So in order to generate white at 5600K with a full colour spectrum (high CRI/TLCI) we are mixing the outputs from 7 different arrays together

    We use only the top 0.1% of arrays produced, and then there are complex algorithms running which ensure the output is repeatable between different fixture and takes account of the LED degradation from age/use (pretty much 20,000 hrs is the limit before is all starts drifting)

    By contrast your divelight/video light will have a single array of some mixed colours and perhaps a and additional red boost but the variance between units of the same manufacturer can be different.

    On top of that power and Lumen outputs need to be taken with a truck full of salt. Unless you've got a test bench, can you disprove their claims?

    You should know that heat is a huge issue, not only at teh back of the array, but from the front. There needs to be a collimator and lense on the front of the array, these heat up massively due to friction from teh photons - so design and material choice is paramount, then reflector design and teh main lense design come into play.

    Put a light meter in front of one of these lights and you'll be disappointed with the results.

    For the diver - then whats the answer? None really - you won't be able to tell until you see the results on your camera. Just be aware that lots of claims by the lighting manufacturers are quite creative...
     
  2. XTAR

    XTAR Dive Equipment Manufacturer

    # of Dives: I'm a Fish!
    Location: China
    190
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  3. D_Fresh

    D_Fresh ScubaBoard Supporter ScubaBoard Supporter

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  4. DivingColeridge

    DivingColeridge Divemaster

    # of Dives: 100 - 199
    Location: Christchurch
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  5. CT-Rich

    CT-Rich ScubaBoard Supporter ScubaBoard Supporter

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    I have several wide beam video lights (120degree). I like them because they don’t create hotspots when filming. I recently bought a more general purpose dive light that is good for poking under rocks or night diving (I like a narrower beam on night dives). I found this one on Amazon and have been pretty happy with it so far (three dives, max depth 40’). The price was right, so I am not going to be overly critical of the assertions in the ad.
    https://www.amazon.com/YCS-Flashlig...keywords=Ycs+dive+light&qid=1602768739&sr=8-1
     
    D_Fresh likes this.
  6. Jayfarmlaw

    Jayfarmlaw Divemaster

    # of Dives: 200 - 499
    Location: Tuttle, Ok
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    We love our 4 Dive Gear Express lights, one is 5 years old and still going strong. They show 6500k but we have never had an issue with color. We get well over an hour of dive time with ours. Best $59 Ive spent. The 800 is a little brighter but not by much. The 600's are the perfect size and perfect amount of light.

    DGX 600 TWIST Handheld Light

    Good luck,
    Jay
     
  7. D_Fresh

    D_Fresh ScubaBoard Supporter ScubaBoard Supporter

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    Honestly, I really regret not scooping a DGX light (or 3) when I had the chance.... But based on my location, the opportunity only presents itself a few times a year...
     
  8. Diving Dubai

    Diving Dubai Instructor, Scuba

    # of Dives: 1,000 - 2,499
    Location: Dubai UAE
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    Little pro tip. When choosing a light, shine it at a wall then view via your phone camera. Your eyes and brain will compensate making the field look uniform, a phone camera is quite rudimentary and will easily some hot or dark pots across the beam field

    rough and ready it might be but it’s a good enough test which anyone can do.
     
    D_Fresh and CT-Rich like this.
  9. Tyflies

    Tyflies Garibaldi

    # of Dives: 100 - 199
    Location: Fort Worth
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    Did you decide on a light that you like? I’m looking for a barrel light with as warm of a color as possible too.
    I had it narrowed down to the Orcatorch D550 or D520. Orcatorch says the 520 is 5000k in description - but it and the 550 use the same LED and LED manufacturer says it’s 6500k (which is pretty blue).
     
  10. boat sju

    boat sju Loggerhead Turtle

    # of Dives: 200 - 499
    Location: Haslett, Michigan
    1,480
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    Tyflies,
    I have a D520 and it seems pretty "white". I don't think it's 6500k. Before I retired I was involved some with freeway lighting design. Color temp was an issue for us.
     
    D_Fresh likes this.

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