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Godox AD600BM to modify for UV

UV Lighting
6 replies to this topic

#1 UlfW

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Posted 16 January 2019 - 19:35

I am considering getting a Godox AD600BM to modify for UV as I feel the output from my Godox AD200 is a bit to weak.
Something like this set would be nice and portable:
https://www.ebay.com...ng/283082472135

The flash tube must be replaced as the original tube is likely to be UV-filtered.
I am playing with the idea of get a customised flash-tube from https://www.xenonfla...-lamps-design_9
They can make as few as one single tube, but the price will most probably be lower if more than one will be made.
I have not asked them for a cost indication yet and wonder if someone else at the forum might be interested to join this adventure.

Edited by UlfW, 18 January 2019 - 09:22.

Ulf Wilhelmson
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#2 nfoto

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Posted 17 January 2019 - 11:05

The flash tube company you linked to has some quite interesting UV-capable Xenon tubes ... not cheap, though. I might buy new 800 or 1600 WS units for my Broncolor studio flashes. Thanks for the heads-up.

#3 UlfW

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Posted 17 January 2019 - 13:25

I did some preliminary spectral-tests with three different flash-tubes from xenonflashtubes.com, mounted on my Godox AD200.
I wanted to check the spectrums to see if the behaviours might be acceptable for bigger types, suited for Godox AD600.
Attached Image: IMG_1714.JPG

Attached Image: Screen Shot 2019-01-16 at 19.28.37.png

In the diagram
Purple, the straight 250Ws quartz-tube: https://www.xenonfla...l-lamp_121.html
Green, the small 40Ws glass spiral-tube: https://www.xenonfla...be-lamp_79.html
Red, the 200Ws glass ring-tube: https://www.xenonfla...p-200ws_73.html
Cyan. The godox speedlight head on the AD200

The curves are normalised for the same average level between 470nm and 650nm.

The measurement was done by bouncing the light from the flash onto a clean 5mm thick PTFE sheet and feeding the reflected light by a fibre to the spectrometer.
The AD200 had the standard reflector mounted, except with the speedlight head.

It was very clear that the ring tube was not efficiently reflected by the reflector geometry.

The quartz tube match the reflector geometry quite well and it can handle the maximum energy of the flash with some margin. It gave the highest directional light output.
The ratio between VIS and UV-A is also quite nice. I like the performance, but I have to arrange a filter to stop UV-B and UV-C.

The small spiral flash-tube, originally mentioned by Enrico, is severely under-dimensioned (40Ws). With short time between flashes, the glass melt inside of the tube.
I have so far killed two of those. With enough cooling-time between flashes it will likely survive longer.


My conclusion based on the spectras is that I will go for some type of quartz tube and arrange a suitable UV-A pass filter.

Depending on the geometry of the original AD600 flash-tube and reflector it might be either of these:
https://www.xenonfla...studio_160.html
https://www.xenonfla...studio_166.html

Edited by UlfW, 18 January 2019 - 09:55.

Ulf Wilhelmson
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#4 dabateman

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Posted 17 January 2019 - 14:32

That purple graph line looks excellent. 35% at 300nm with low IR, max peak about 40% at 825nm. That would be outstanding for outside UVb imaging with a 313nm or 300nm filter. The cost isn't too prohibitive either.
Something to think about.

#5 UlfW

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Posted 17 January 2019 - 16:27

View Postdabateman, on 17 January 2019 - 14:32, said:

That purple graph line looks excellent. 35% at 300nm with low IR, max peak about 40% at 825nm. That would be outstanding for outside UVb imaging with a 313nm or 300nm filter. The cost isn't too prohibitive either.
Something to think about.
The amplitudes for different wavelengths are not calibrated as I do not have access to any amplitude calibration source.
This is the result of the response of the grating used in the spectrometer only. The IR part amplitudes are not comparable with the UV-part.
However the response-variation isn't that quick and levels in the same region are reasonably comparable.

Also I normalised against a rather big range of wavelengths to get a reasonably common level in VIS for all spectra, to better be able to compare the differences in UV-energy.
It is not 35% at 300nm compared to the maximum amplitude in VIS.

Edited by UlfW, 18 January 2019 - 09:57.

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#6 nfoto

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Posted 18 January 2019 - 18:59

I ordered this: HPR-6069 Round 1600ws Flash tube Quartz Lamp which is an exact fit to my Broncolor studio flashes.

#7 UlfW

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Posted 01 February 2019 - 15:50

A status update:

The Godox AD600BM-kit I mentioned in my first post has arrived.
It still looks promising and I think it will work well in the field.
It is not too heavy to carry and the standard flash lamp is powerful.
A 600Ws battery powered flash, recycling in two seconds after flashing at full power is rather impressive!

I have also ordered the same HPR-6069 Round 1600ws Flash tube Quartz Lamp as Birna mentioned above.
The flash tube looks to have a similar shape and size as the tube in the more modern and expensive Godox AD600 Pro.
I intend to use the Bowens mount standard reflector designed for that flash.
The reflector is more compact with only 120mm in diameter compared to the big 180mm reflector designed for AD600BM.
I have the reflector and it fits well.

To filter UV-B and -C I have ordered UV-grade Perspex-sheets from
http://www.plasticst...ylic-Sheet.aspx
They were nice and could cut circular discs to the diameter I wanted for a reasonable cost.
Attached File  Perspex - UVT.PDF   116.1K   18 downloads

I designed a new Circuit board (PCB) to aid the connection of the flash-tube with banana-connectors in fitting positions to the flash.
The PCB is under production in China now.
I'll get ten PCBs and will not need more than a few of them, most likely only one.
I can share the rest of the boards if someone like to use the same design in the future.

Edited by UlfW, 01 February 2019 - 16:59.

Ulf Wilhelmson
Curious and trying to see the invisible.