How much light do we need?

Hi guys,

Currently i am looking for some video lights but i am blinded by the options i have B)

There are 10W dual HID's to 200W HMI lights available and everything in between.

And then there is the LED system based on the latest generation of power LED's.

So it made me wonder how much light we need for filming a dive within recreational limits (40M/130FT) on an average day.

The goal is to get a good picture quality and marine life without sunglasses (or no marine life at all).

If a based my overview on wrong facts, please let me know and i will correct this.

# of lumens for your Dollar

This is based on specs i could find on various websites or to use the maximum number of lumens per watt WITHOUT an reflector,

some products are from overseas so i converted straight to the dollar (i didn't calculate any tax or import duties whatsoever).

For the maximum number of lumens per watt see the sources section.

Remember this overview is only to get an idea not as an official overview.

4.05 lumen / $ -- 15000+ lumen Heliumnizer 200W HMI @ $ 3700,- (guesstimate on DIY part prices)

2.90 lumen / $ -- 8000 lumen (2x 4000) Seastar (50W HID) @ $ 2750,-

2.37 lumen / $ -- 5600 lumen (2x 2800) Seastar (35W HID) @ $ 2360,-

2.30 lumen / $ -- 15000+ lumen Halcyon Apollo 200W HMI @ $6500,- (old halcyon price)

1.20 lumen / $ -- 2900 lumen (2x 1450) Professional Video Light (24W HID)@ $2400,-

1.05 lumen / $ -- 4000 lumen (2x 2000) Sunray 2000 (LED) @ $ 3799,-

0.76 lumen / $ -- 2600 lumen (2x 1300) Sunray Pro (21W HID)@ $ 1899,-

0.40 lumen / $ -- 2000 lumen (2x 1000) Sunray 1000 (LED) @ $2499,-

Sources

HID has about 60 lumens per watt

HMI 85-108 lumens per watt

LED up to 131 lumens per watt

Thank you !!

Michael

Michael

Thanks for the good research into prices and specs. However some of the specs are a bit more marketing voodoo than facts.

HID has pretty high efficiency... if you don't count the ballast, which often all the marketing people never do. It is still higher than halogen, but the margin isn't as wide as they'd want it to be.

Please read the video lights primer for more info.

As for choice, you can't choose based on light output alone. There's CRI, width of beam, hotspots and also you have to consider the lamphead and battery design.

Some people like to have everything on the housing, which is fine for smaller battery packs but impractical for bigger packs. The housing would require a lot of floating to compensate. Conversely, if you have the lamphead and batteries all in one package on arms, you run into balance problems.

Now to answer your question about how much light is needed, it depends on what you are shooting in daytime. A wreck requires as much light as you can get and the beam to be extra wide. Even with my 200W HMI, the light sorta fades after 5-6 feet because I diffuse it to even out the beam and prevent hotspots and overcooking the highlights.

If you are shooting macro, you don't need as much power but more on the color temperature to match the background light so you don't get that awful cyan tint. You can use a filter to compensate, esp with HID/HMI LED since they are in the 5600-6500°K temp range, which color filters are balanced at 5800°K.

If you are trying to use the lights as fill, in shallow water... obviously you need more power.

Hi Drew,

I've read the video lights primer but there is quite some information in there ,

i'll read it again maybe this time i understand it a little bit better.

About the dives, they will be "normal" dives you know, some coral, fish a diver that stuff.

Most of the time i will not be going deeper then 20 ~ 25 meter and at widest about 80 degree.

Based on your answer i think there is no standard setup for underwater video.

In fact the environment can change so rapidly (from wide to macro) that you need various light type's.

At least that is how i interpret the answer you given me.

So what about a single 200W HMI (or dual 50W HID) for wide shots and fill light at shallow depths

Combined with a "spotlight" to light out an oncoming diver that is +2M/6FT away.

This spotlight can also be used as an light for macro shots if the "main" light is switched off.

Do i make sense or is it better to steer away from the underwater lights for a little while longer

Thanks for your answer Drew!

It all depends on what you are shooting. Obviously a switchable lamphead offers the most versatility, but often isn't the most powerful.

I can't recommend the HMI as it is pretty expensive and a specialist tool but then again you don't say what you want the lights for. I don't like recommending systems because it is difficult to do so. Which is why I wrote the primer so that readers can understand the basics of lights and make a decision on their own.