For those of you that want to get away from the CRoW posts and you want to shed more light on your underworld then why not get a million lumen of power.

The Vela One, on kickstarter right now, designed in Bristol.

https://www.kickstarter.com/projects/vela/vela-one-the-worlds-first-high-speed-led-flash
http://www.vela.io/

Focus seems to be on high speed photography but could this do anything for caving photography ?

Longer flash pulses are possible but I suspect these will need to be lower power to protect the LED's.
Their circuit overdrives the LED's by twenty times and reportedly does no harm presumably because the flash duration is so small.  Unit is physically big.

There is a subscription level on kickstarter for nine units.
Anyone for 9,000,000 lumen ?

For an earlier verdict on the million candlepower lamp...

https://www.youtube.com/watch?v=Vt8aAy_8Ub4

Bottlebank said:

For an earlier verdict on the million candlepower lamp...

https://www.youtube.com/watch?v=Vt8aAy_8Ub4

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Great. 

spot on

For those who want an interpretation of the last three posts, they refer to a stand up routine by a gobby Welshman stand up comedian, no real reference to the OP.

Myself, I would be interested in the ideas of folks as to how this could be applied to cave photography, not knowing much about digital, what about the response times and co-ordination between the camera, the trigger, and the 1,000,000 lumens?

The blurb indicates brightness and speed of flash, but nothing about capturing the image.?
It is also a plea for developement funding, no indication of cost.

I take issue with their claim that it doesn't damage the LED. I rather think it's lifetime will be reduced.

Chris.

The lamp is evidently a very high-speed flash that works by operating the LEDs for a very brief space of time.  You set up everything in pitch darkness with your camera shutter in the open position and trigger the flash at the exact moment that your bullet strikes your tomato or your falling rock lands on your elderly excavator.  Very high lumens coupled with very brief exposure gives just enough light for a good picture of an instantaneous event.

As to the effects of overdriving the LEDs for a couple of milliseconds - I'll leave the experts to answer that one.

Roger W said:

You set up everything in pitch darkness with your camera shutter in the open position

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Can you do that with digital, or doe's it have to be set in 'video' mode?

Dunno, Bograt.  I do possess a digital thingy these days, but when I did fancy stuff I used a good old Olympus OM4.

Of course, you would only set the shutter to "open" after you'd turned all the lights out... 

I should think you could do it with a suitable digital by setting a suitably long exposure and then using the self timer button to delay the exposure and give you time to turn the lights out.  Then you'd be in darkness, so your camera wouldn't record anything during the 3-second exposure or whatever you had used except for those few milliseconds when the flash went off.

<<Afterthought added...>>

Roger W said:

Dunno, Bograt.  I do possess a digital thingy these days, but when I did fancy stuff I used a good old Olympus OM4.

Of course, you would only set the shutter to "open" after you'd turned all the lights out... 

I should think you could do it with a suitable digital by setting a suitably long exposure and then using the self timer button to delay the exposure and give you time to turn the lights out.  Then you'd be in darkness, so your camera wouldn't record anything during the 3-second exposure or whatever you had used except for those few milliseconds when the flash went off.

<<Afterthought added...>>

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AARRGGHH, brains gone whatever happened to the old faithfull 'B'stop on cable release, -- 'One' - 'Two' - 'Three' - ' FLASH', - -  is there no 'B' stop cable release on digitals?

If not, I cannot see any use for this 1,000,000 lumen job for our purpose unless a LOT of synchronisation work is proved.

bograt said:

AARRGGHH, brains gone whatever happened to the old faithfull 'B'stop on cable release, -- 'One' - 'Two' - 'Three' - ' FLASH', - -  is there no 'B' stop cable release on digitals?

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Yes, yes there is. Although a lot of them tend to have an upper limit when they'll cut off to avoid sensor issues...

bograt said:

If not, I cannot see any use for this 1,000,000 lumen job for our purpose unless a LOT of synchronisation work is proved.

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Very little of what we normally do in caves happens at the sort of speeds that require this sort of kit. Maybe capturing drip splashes, but triggering would be the issue...

I guess a more accurate measure of "flash intensity" is lumenseconds, i.e. light intensity times light duration. You can take an awesome picture of a huge chamber with just a feeble Duo, if you leave the light on for an hour or so and expose the camera sensor equally long. You could get the same picture with a standard flashgun, which is obviously much brighter, but only has to be on for about 1-5 ms. Or you could get the same picture with a "device" that is a million lumen bright and only switched on for a fraction of a millisecond. Now the only difference is if there are things moving in the time you take the picture. Obviously, if cavers walk around in your huge chamber, an exposure of an hour is not going to work well because the people will be all blurred. For such applications a normal flashgun is much better suited, because people don't tend to move much in the millisecond or so the flash is on. But if you want to take pictures of things like a bullet, then you'll find that they are all blurred, as they move quite a lot even in a single millisecond. That's what this "million lumen" thing is all about. For cave photography I'd say it's useless...

There is a "B" setting on Digital SLRs but it is not always available on the compact digital cameras.
The trick with the compacts is to set the shutter to a long time setting, quite often there is a setting in excess of 4 secs and sometimes as long as 16 secs.

How about the amount of light coming from it?, I suspect that much illumination coming from one direction would give a flat appearance with deep shadows, interesting effect going from over-exposure to dark?, concentration on focal point a serious issue?

I understand that most digitals have automatic light handling capabilities, how are they going to manage a blast of this intensity?.

As a point of reference, I find that my 11000 lumen caplamp is approximately equivalent to a normal SLR type flash unit. It makes point & click photos underground pretty straightforward (provided you don't want to faff about with the arty stuff, i.e. placing multiple slaves etc).

I would think that a million lumens (allegedly) is only really useful for photos like those on the kickstarter, where you are trying to freeze very rapid action.

Chris.

If you go for an hours exposure with a duo and an odd caver walks about with there lamp off and not immediately infront of yours they will simply dissapear on the final shot

As Antwan says, if you go for a really long exposure underground shot, someone walking across in front of the camera probably wouldn't register at all.  It's like those night photos where you see long red streaks from vehicle tail lights but no cars at all.

Re-reading the Vela One page, I see we are talking about flashes in the nanosecond to microsecond range.  Very short flashes for capturing very rapid events.  You don't need anything like that for getting shots of water droplets falling from stalactites or cavers falling into pools of water.  No use at all for cave photography, I should think... 

ChrisJC,

There's no way that your large caplamp is anywhere near equal to a flash gun. A normal unit could correctly expose a persons face, 8m away, at F4, at 1/1000s, ISO 100.

If your light can expose anything well at 1/1000s, ISO 100, I'd be surprised.

I don't doubt that it is perfectly usable for handheld shots though.

I also think that this kickstarter flash isn't going to be that useful for underground photography.

At full power, a typical flash lasts ~1/1000 s, which would be enough for a falling water droplet to travel by about it's own length (at terminal velocity). This does give some blur in photos. At low power however, a flash could be 1/20 000 s, which would effectively freeze water. Little else moves very fast underground (hopefully!).

However, what they have done is successfully make an LED flash gun. I think this could be interesting for caving as it may be possible to DIY one much more easily than a conventional flash, whether it had a fast discharge speed or a more conventional one.

I don't think syncronizing a "standard" digital camera with this unit will be difficult. From what i can tell it should work just like a normal external flash running off a cable (although you may need to do some jiggery regarding getting the audio jack out).

I also believe this is pretty unnecessary for caving, as modern external flashes on low power are quick enough.

And I agree with blackholesun that the use of LEDs to replace standard flash tech could be the future...