Vela flash

Sir SR

Sir SR

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Shaheed
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Heard this mentioned. Some kind of high speed flash. Anybody heard or know anything about it?

Ta

Shaheed
 
TG. said:
Some type of high speed LED flash, but I'm guessing you already know that Shaheed, just Googled and got this https://www.kickstarter.com/projects/vela/vela-one-the-worlds-first-high-speed-led-flash be interesting to hear what Garry and Hoppy (Richard) think of it :)
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I only found out it's was LED yesterday in fact!! A friend's cousin is heavily involved with it which is why she mentioned it to me the other day!

I too would be interested in Garry's and Hoppy's thoughts!
 
It sounds fascinating, but the blurb doesn't have enough detail to convince me.

Basically, there are a couple of things that bother me...

They are asking for £25K- that's a very, very low figure for developing a totally new product.
They talk about "the Vela One will stop a supersonic, high velocity rifle bullet in its tracks." which is fine, but what they show in their example photo is a little copper coated ball from a low powered air pistol, moving at maybe 400 feet per second - if it really will stop a supersonic high velocity rifle bullet in its tracks, why not prove it by showing that?

I don't claim to be an expert on rifle bullets but as it happens I do have an interest in shooting and do have some rifles that fire supersonic bullets. My smallest one, a .17 HMR, has a muzzle velocity of 2500 feet per second and the next one up in my cabinet, a .243 loaded with a 50 grain bullet, has a muzzle velocity of 3950 feet per second - both very different from a low powered air pistol!

Edit: Given that the speed of sound (at sea level) is 330 mps or 1000 feet per second, I suppose it could be argued that the humble .22 long rifle bullet is just about supersonic, but even this is much faster than the 'bullet" in the photo. However, I have doubts about the photo, because the destruction here is pretty typical of a low powered rifle bullet... If I had a suspicious mind I might wonder whether it was a genuine photo of the fruit being exploded by the hydraulic effect of the impact from a .22 or similar, and that the little copper coated ball is just a dust spot on the sensor...
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Hi,
I'm Matt from Vela. I just spotted this and thought it would be good to drop in and answer a few of the questions posed in the thread.
As you can understand, the reason the photos are all done with a BB gun is simply because I don't have access to real firearms. The reason I can confidently say it can freeze a supersonic bullet is because I have accurately measured the flash pulse width (using a Thorlabs DET10A photodetector connected to an oscilloscope), and it's around 500 nanoseconds (1/2,000,000). A round travelling at 1000m/s = 1mm/microsecond, so will have half a mm of motion blur.
Now I realise that showing is better than explaining, so I've been trying to arrange to get access to some real guns. I'm happy to say that I have a meeting at a gun club this evening, and hope to have a shoot next week. I'll hopefully then have some pics to share.

Regarding the £25k target, bear in mind that's not the full budget. I've already spent a lot of my own money getting it to this stage, plus a couple of grand in grant funding. £25k is what it takes to do the final round of revisions, and place the order for manufacturing. That order would be for more than the ones for Kickstarter backers, and I'd hope to recoup my costs with selling those. However I'm happy to say that we're now over £30k with two weeks remaining, so should have more breathing room on the budget.

Re the veracity of the photos, here's a raw file of one that I have on this computer, which you're welcome to verify. https://www.dropbox.com/s/6qe0r9fwsgnw4f8/PB040053.ORF?dl=0 I don't have the raws for the grape and tomato photoshoot, as they were taken on a friend's 5D Mk II, and he took them off onto his computer as I don't have a CF card reader. If you're still sceptical I can get hold of one of them too. I was surprised as anyone with how cool the grapes etc look. That said, it doesn't take much to squash a grape, so you shouldn't be surprised that it easily rips through it. I'm planning to take apples to the real shoot, which the BB gun wouldn't be much use for. And if I was faking it, why wouldn't I fake it with a real bullet rather than a BB?
 
ascorbic said:
Hi,
I'm Matt from Vela. I just spotted this and thought it would be good to drop in and answer a few of the questions posed in the thread.
As you can understand, the reason the photos are all done with a BB gun is simply because I don't have access to real firearms. The reason I can confidently say it can freeze a supersonic bullet is because I have accurately measured the flash pulse width (using a Thorlabs DET10A photodetector connected to an oscilloscope), and it's around 500 nanoseconds (1/2,000,000). A round travelling at 1000m/s = 1mm/microsecond, so will have half a mm of motion blur.
Now I realise that showing is better than explaining, so I've been trying to arrange to get access to some real guns. I'm happy to say that I have a meeting at a gun club this evening, and hope to have a shoot next week. I'll hopefully then have some pics to share.

Regarding the £25k target, bear in mind that's not the full budget. I've already spent a lot of my own money getting it to this stage, plus a couple of grand in grant funding. £25k is what it takes to do the final round of revisions, and place the order for manufacturing. That order would be for more than the ones for Kickstarter backers, and I'd hope to recoup my costs with selling those. However I'm happy to say that we're now over £30k with two weeks remaining, so should have more breathing room on the budget.

Re the veracity of the photos, here's a raw file of one that I have on this computer, which you're welcome to verify. https://www.dropbox.com/s/6qe0r9fwsgnw4f8/PB040053.ORF?dl=0 I don't have the raws for the grape and tomato photoshoot, as they were taken on a friend's 5D Mk II, and he took them off onto his computer as I don't have a CF card reader. If you're still sceptical I can get hold of one of them too. I was surprised as anyone with how cool the grapes etc look. That said, it doesn't take much to squash a grape, so you shouldn't be surprised that it easily rips through it. I'm planning to take apples to the real shoot, which the BB gun wouldn't be much use for. And if I was faking it, why wouldn't I fake it with a real bullet rather than a BB?
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Interesting, and thanks for your response.

What got me a bit to be frank was your reference to a supersonic bullet when the 'bullet' shown in the shot was nothing more than a BB from a low powered airgun, which isn't a problem for me personally because I know the difference between the two - but my guess is that most viewers wouldn't see this.

Oscilloscope tests can be useful, but in my experience oscilloscopes have their limitations when the pulses are extremely short, and so practical tests are likely to be essential.

Let's hope that the gun club can help. However, you may or may not be aware that most gun clubs are licensed for certain calibres only, it is very possible that the club you're hoping to get help from may be limited to something like a .22 rimfire, which is only around the cusp of supersonic muzzle velocity (different rounds vary slightly) and so you may not be able to test with true supersonic rounds - and nobody at a club will shoot other than in accordance with their license. And frangible/expanding bullets can't be fired at ranges, and supersonic bullets are mostly frangible. However, if this becomes a problem then just get in touch with me, as I have some very powerful rifles and a full open certificate, and can set up tests at a suitable licensed range with non-frangible rounds. Alternatively, I could put you in touch with shooting forums, where there will be members that can help, if you're a long way from me.
 
Yes, you're right. I believe this range is only licensed for .22s. Even if it's not high velocity it will at least give me a chance to prove that it works with real bullets. Bigger stuff would be the next step. Some help there would certainly be appreciated. I see you're in Bradford. I'm in Bristol, so quite a way from you unfortunately. A photographer nearby with a firearm certificate would be my holy grail.
 
ascorbic said:
Yes, you're right. I believe this range is only licensed for .22s. Even if it's not high velocity it will at least give me a chance to prove that it works with real bullets. Bigger stuff would be the next step. Some help there would certainly be appreciated. I see you're in Bradford. I'm in Bristol, so quite a way from you unfortunately. A photographer nearby with a firearm certificate would be my holy grail.
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This all looks very interesting Matt - Chloe and Alex told me about this initially. Cheers for the extra info!

Shaheed
 
I've downloaded that file, but unfortunately can't open it in PS
 
is this a good time to mention the excellent advertising packages we offer here at TP? (i cant open the file either)
 
It's an Olympus raw file. Maybe you'd have better luck with Lightroom or Aperture?
 
Garry Edwards said:
Interesting, and thanks for your response.

What got me a bit to be frank was your reference to a supersonic bullet when the 'bullet' shown in the shot was nothing more than a BB from a low powered airgun, which isn't a problem for me personally because I know the difference between the two - but my guess is that most viewers wouldn't see this.

Oscilloscope tests can be useful, but in my experience oscilloscopes have their limitations when the pulses are extremely short, and so practical tests are likely to be essential.

Let's hope that the gun club can help. However, you may or may not be aware that most gun clubs are licensed for certain calibres only, it is very possible that the club you're hoping to get help from may be limited to something like a .22 rimfire, which is only around the cusp of supersonic muzzle velocity (different rounds vary slightly) and so you may not be able to test with true supersonic rounds - and nobody at a club will shoot other than in accordance with their license. And frangible/expanding bullets can't be fired at ranges, and supersonic bullets are mostly frangible. However, if this becomes a problem then just get in touch with me, as I have some very powerful rifles and a full open certificate, and can set up tests at a suitable licensed range with non-frangible rounds. Alternatively, I could put you in touch with shooting forums, where there will be members that can help, if you're a long way from me.
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I've got nothing to add, but isn't this the perfect thread for you Garry?

(maybe could be improved with a pretty girl)
 
ascorbic said:
It's an Olympus raw file. Maybe you'd have better luck with Lightroom or Aperture?
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Ahh, don't have either of those. A pity, as I would have liked to see the exif data.
 
Phil V said:
I've got nothing to add, but isn't this the perfect thread for you Garry?

(maybe could be improved with a pretty girl)
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Nah, my certificates don't allow me to shoot girls, pretty or otherwise:)
 
HoppyUK said:
There's a news item about this on DPReview http://www.dpreview.com/articles/54...uration-for-the-price-of-a-normal-hotshoe-gun The most useful bit of info there is "the Vela One was placed 60cm/2 feet from the subject to give an exposure of f/7.1 and ISO 800".
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Well, that's putting it firmly into macro and closeup territory only. I think that this may be the right time to launch it though, with digital camera technology now allowing the use of high ISO figures without too much IQ impact. Power testing is normally carried out at the benchmark of 100 ISO but there clearly isn't enough power for that.

What I'm finding a bit strange is that there is very clear movement showing in the unfortunate grape, and also in what must be the 'vapour trail' produced by the CO2 from the airgun, but that little ball pellet is pretty sharp. Maybe I'm wrong, but I wouldn't have expected such a low powered airgun to produce a noticeable hydraulic effect - even on something as wet and small as a grape - to make the bits of grape move much faster than the pellet.

Tests with even a .22 LR bullet at around 330 mps should be interesting - the actual muzzle speed will depend on the bullet, and will be printed on the box. These figures are affected by height about sea level and ambient temperature, neither of which will make any real world difference, and by barrel length, which again doesn't matter with the humble .22
 
It is certainly designed for closeup, but most bullet stuff would fall under that. I took exactly the same judgement about the ISO issue. High speed is always a balance between brightness and speed, and I think that with these latest LEDs it was finally bright enough. Hopefully in the next year there will be new LEDs that I can drive even brighter.

All I can say is that I know that I took those photos, and they're real! Most of the blurring in these pics is focus. As you can imagine, focussing on the path of a BB is a bit tough, especially when you're aiming in the dark!
 
ascorbic said:
It is certainly designed for closeup, but most bullet stuff would fall under that. I took exactly the same judgement about the ISO issue. High speed is always a balance between brightness and speed, and I think that with these latest LEDs it was finally bright enough. Hopefully in the next year there will be new LEDs that I can drive even brighter.

All I can say is that I know that I took those photos, and they're real! Most of the blurring in these pics is focus. As you can imagine, focussing on the path of a BB is a bit tough, especially when you're aiming in the dark!
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Well, the way to do it is to choose your focus point - in this case I'm guessing it will need to be where the pellet is going to exit - in the light. The autofocus does of course need to be switched off. At this kind of distance, even if you had enough power to allow the use of a much smaller aperture, you still wouldn't get all the bits of grape in focus.
 
Yeah, that's what I did do. The problem is aiming the gun at the right point on the grape! Some of my earlier pics have the gun in a vice, which helped when I was shooting in my "studio in a box".
 
Garry (and Matt). Does it have to be a rifled round? How about a shotgun? I'd love to see a capture of the wad, pellets etc.
 
I manually pressed the shutter, with a 2 second exposure on most of them. The flash was triggered with a sound sensor. I mainly use a DIY trigger, though some of the better shots were done with a Triggertrap Ada prototype.
 
ascorbic said:
I would *love* to see shotgun pics taken with it. These shotgun photos taken with an airgap flash are stunning: http://kuulapaa.com/home/highspeed/Misc.html
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FlyTVR said:
Garry (and Matt). Does it have to be a rifled round? How about a shotgun? I'd love to see a capture of the wad, pellets etc.
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Well, shotgun use isn't nearly as tightly regulated, but due to the devastation at short range, would need to be fired outdoors I think. Those example photos though included several types of cartridge that aren't available for legal reasons in the UK.

The MV of a typical shotgun cartridge is around 1450 fps
 
ascorbic said:
It is certainly designed for closeup, but most bullet stuff would fall under that. I took exactly the same judgement about the ISO issue. High speed is always a balance between brightness and speed, and I think that with these latest LEDs it was finally bright enough. Hopefully in the next year there will be new LEDs that I can drive even brighter.

All I can say is that I know that I took those photos, and they're real! Most of the blurring in these pics is focus. As you can imagine, focussing on the path of a BB is a bit tough, especially when you're aiming in the dark!
Click to expand...

Less of a focus problem I think, more a depth of field issue. That's what the grape looks like to me, rather than motion blur.

But it does make the point about how close you need to be to get enough light. Just looking at the reflector design of the prototype, there's a wide spread of light. I would guess that a tighter beam from maybe a Fresnel type lens (speedlight style) or just a deeper more parabolic reflector might make a significant difference. Something like double the effective brightness might be possible - pure guess, but could easily be of that order.

All this talk of guns, shot-guns and military-grade firearms - that's a tiny, tiny market...
 
HoppyUK said:
Less of a focus problem I think, more a depth of field issue. That's what the grape looks like to me, rather than motion blur.

But it does make the point about how close you need to be to get enough light. Just looking at the reflector design of the prototype, there's a wide spread of light. I would guess that a tighter beam from maybe a Fresnel type lens (speedlight style) or just a deeper more parabolic reflector might make a significant difference. Something like double the effective brightness might be possible - pure guess, but could easily be of that order.

All this talk of guns, shot-guns and military-grade firearms - that's a tiny, tiny market...
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Some valid points there...
And of course you're right about guns being a tiny market, and anyway it's all been photographed to death using different technology, and small arms ammo doesn't exactly change much with the passage of time anyway.

But I suspect that Matt just wants to use bullets to prove the short flash duration of his product, and has other markets in mind.
 
Garry Edwards said:
Some valid points there...
And of course you're right about guns being a tiny market, and anyway it's all been photographed to death using different technology, and small arms ammo doesn't exactly change much with the passage of time anyway.

But I suspect that Matt just wants to use bullets to prove the short flash duration of his product, and has other markets in mind.
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Sure, but the limited brightness restricts it to small subjects, and small subjects that move so fast that they require 1/2,000,000th of second are few and far between.

From a pictorial photographic point of view, there would be more interest in something that puts out more light, to cover subjects that don't need anything like that kind of short duration. But hot-shoe speedlites are perfect for that.

On the other hand, the scientific and industrial applications must be numerous - though a smaller market in terms of units.
 
This isn't meant to replace your speedlight or studio strobe. It is a specialist device for high-speed photography, and has lots of advantages over the alternatives.
 
How did you get on at the rifle club Matt? I really do feel that you need to get example photos that show its capabilities better.
 
ascorbic said:
This isn't meant to replace your speedlight or studio strobe. It is a specialist device for high-speed photography, and has lots of advantages over the alternatives.
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I can see some interesting forensic uses for this in addition to ballistic tests namely blood patten analysis (BPA) and spatter distribution / reconstruction tests.
 
I'm shooting tonight! I visited the club last week and met with the secretary to arrange it all. Very excited.
 
ascorbic said:
I'm shooting tonight! I visited the club last week and met with the secretary to arrange it all. Very excited.
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That's good news, look forward to seeing the results.
Next step up though will have to be with a faster bullet that's supersonic, the obvious answer to that one is a .17 HMR at 2500 fps, it would look pretty because the bullet has a copper coat and a coloured tip, but that can't be done at a rifle range.
20091016145258-17_hmr_ammo_ms.jpg
 
Well, I had fun at the range last night! I only had an hour though, which was pretty frustrating, as it took quite a long time to get everything set up and all the timings working with the triggers. However I did manage to get some shots I'm happy with. I'm hoping to arrange a full day there, which would give a lot more opportunity for good shots.
This is one of the ones where we did manage to get the bullet both in frame and not inside the apple at the time! Unfortunately it's a little out of focus, but hopefully you can see the lack of motion blur.

View attachment 26696
 
I have some good news about the power though. I've been doing some more testing this week and it turns out I'm getting less power from this prototype than from the previous, non-pretty one. From looking at the waveforms it's clear that this is because the rise time is a lot slower than in the previous version. From more tests it seems this is down to parasitic inductance from the wiring of the luminaire (the bit with the LEDs). The good news is that more tests show we can significantly improve the power by changing the way the LEDs are wired. It looks like it could be 30% more power at least (but no promises yet). I was already working on a new design for the luminaire so make it easier to assemble (right now it's nine individual holders wired together, which is quite fiddly). The new version will have a lot lower inductance, as the LEDs are mounted directly to the board. This means the rise time will be a lot shorter, meaning the total exposure over the period is higher.
 
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