365nm UV Flash?

[Pylon]

Contrary to what B+H claims in the advert, the UV attachment for Broncolor studio flashes (it fits the MiniCom series as well) emits lots of IR. I briefly tested it and saw no obvious advantage of paying this much for a pretty useless accessory. Must have been developed with film-based photography in mind? Besides the heavy IR output, you cannot use ordinary flash reflectors and other studio gear with it.

Well, wouldn't the UV attachment come in handy as long as there is no visible light being emitted out of it whatsoever? You could use it for UVIVF (by placing a VIS-only filter on the lens) and UV-only photography (by placing Baader-U on lens). May not be the most ideal set-up in my mind because of the IR as you mentioned, but if the attachment emits no VIS light whatsoever (unlike the sb-140 filters), then I suppose its application is just as useful as a UV-only light as long as you are using it for UV-only photography or UVIVF photography. The benefit I see in it is you get to use a large powerful studio strobe that should hopefully have a super amount of UV light output, which could potentially be used for lighting larger areas like landscapes or entire rooms.

 

Only disadvantage to a UV+IR filter such as the broncolor attachment is that you wouldn't be able to use a full-spectrum camera with no filter on its lens in order to capture an exposure that has a mixture of IR-only, UV-only, and VIS-only light in separate areas of the frame.

[nfoto]

Like the SB-140 filters, the Broncolor attachment also emits some visible light. The IR output is massive. In an experiment, the Broncolor flash was used to photograph IR reflectors off power pylons at a distance of 3 km (in night time) . They came though convincingly.

 

A studio flash has little use if you cannot control its output and light distribution by using reflectors, barn doors, honeycomb grids, umbrellas, softboxes etc.

[baffe]

Metz 45CT1 has a very simple circuit. Easy to modify, easy to repair. Only one main reflector.

 

Metz "45CL4" has SCA-control, low tigger votage, a second small reflector (wich most photograhers don't use) has a control circuit for analoque (real!) TTL. While "45CL4 digital" can perform E-TTL (Canon) and i-TTL (Nikon) control for dslr's.

 

I only have experience with 45CT1.

[Pylon]

Heat up a heavy duty razor knife and just melt around the very edges of the outside yellowed plastic and remove it.

 

Vivitar 285HV modded using a hot blade to melt the plastic. As you can see, the first outer lens of the flash was removed completely, however I tried to cut the the yellow smaller inner lens by first cutting the outer boarder of it, where it touches the black plastic, however all this ended up doing was melting the two pieces of plastic even more. I then just cut a hole in the middle of it then worked my way outward until you get what you see here. Sanded it off a a little but that didn't work very well either, so, yes, it is slightly bumpy and full spectrum light can kinda leak through the uneven bumps because it is not fully flush, however after taping a rectangular UV-A only filter with black electricity tape to the flash, you get a UV-A flash which is slightly less bright than the SB-140:

 

Is this how yours looks Damon or were you able to get a cleaner cut?

[Pylon]

Contrary to what B+H claims in the advert, the UV attachment for Broncolor studio flashes (it fits the MiniCom series as well) emits lots of IR. I briefly tested it and saw no obvious advantage of paying this much for a pretty useless accessory. Must have been developed with film-based photography in mind? Besides the heavy IR output, you cannot use ordinary flash reflectors and other studio gear with it.

 

This video suggests that one could use light modifiers along with the Broncolor UV attachment.

 

Like the SB-140 filters, the Broncolor attachment also emits some visible light.

 

Are you serious? Are you saying that when you use the Broncolor attachment, that there is a very noticable purple color that shows up in the images, very similar to the SB-140's SW-5 UV filter?

[Pylon]

Ah ok, I went back and reviewed the data sheet for the Broncolor attachment and now see what you are saying http://www.bron.ch/u...tachment_en.pdf

 

It looks like it does emit some visible light, but it is very small compared to the rest of the chart that the visible light it does emit is probably similar to how the MTE-301 LED appears when not filtered. It is a small difference but the difference still is there, yes

 

[Pylon]

Does anyone know what UV bulb is being used in this video? http://petapixel.com/2014/12/30/shooting-bikers-night-diy-black-light-flashes-colorful-paint/

[baffe]

...looks like 125W Blacklight bulb to me.

 

Usually we use 250W here but is still available that size (in Germany)!

[Alaun]

Don't they contain mercury, these bulbs? Cutting them up might not be a good idea then (perhaps a counter measure: use a lot of Zn powder, to capture the mercury)

[baffe]

At least they contain traces of Hg as vapour. Always and even the long tubes.

 

But I can tell you if you bring some of the white powder from inside the lamp to a scratch or wound that injury will take a lot of weeks to heal!

 

Things inside any discharging lamp are not very healthy and even the metal isn't pure and coated with materials containing Barium or other bad things.

 

My glassblower has the blacklight tubes without coatings and 1 inch diameter. I prefer that.

[Andrea B.]

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[Pylon]

If only there was a round bulb shaped like this made from 365nm UV-Pass material..... Even though a bulb shape would be ideal, if that is not possible, maybe you could get five square filters and glue them together somehow to cover the omnidirectional flashtube in the monolight. If not that, then 4 pieces of metal and 1 UV-pass filter at the end of it approx 3inx3in. seem like it would at least somewhat work (although I don't know about how wide of an area it would cover). This way you could harness the power of a strobe and lower the ISO which is something that is definitely needed, as none of the light/filter solutions I am finding (besides potentially the Broncolor + attachment) are at all bright enough to produce professional-quality results ( "professional quality" meaning at least F5.6 and ISO400 lit from 2 meters away).

[baffe]

Common Xenon flash tubes have only 2% uv.

 

So I use a modified Metz 45CT1 (150Ws) and a Norman 200B (200Ws) and a homemade unit (180Ws) at close distances to get some uv onto my stones:

 

http://up.picr.de/23562090gp.jpg

 

http://up.picr.de/23562091cn.jpg

 

http://up.picr.de/23562092hn.jpg

 

If I want to put the same power density onto a whole person, puuuh, lot of energy.

[Pylon]

Did some more tests, the Canon 199A is actually brighter than the 285HV, and the SB-140 is brighter than the 199A.

 

To filter the 199A you can either use the Baader-U at the end of a funneled snoot made from step up/down rings, or you can use uviroptic's rectangular filter set. I taped the filters together on the edges only using scotch tape (which I think actually absorbs UV light) then placed it in the rectangular black frame and fit perfectly. Baader-U is brighter in the middle of the light projection, while the rectangular mod gives a wider and more evenly lit spread.

 

 

Using the U-340 alone on the flash without the red/infrared suppression filter provides about an extra stop of light than if you were to use it with the suppression filter. Also, using just the rectangular U-340 alone on the flash with no UV/IR cut on lens adds visible red to the mix and produces a completely different result (it did with my unmodded D810 at least). If you use just the u-340 filter on the flash and the Baader UV/IR cut on your lens, then the visible red is reduced greatly but is still there and does make some objects look more interesting and less dull, specifically on plant life and leafs which is what I tested it on. The SB-140 UV filter does the same thing that the U-340 filter does except visible violet, visible red and infrared are present, and can produce more harsh color effects when using a UV/IR cut on lens (without the uv/ir cut the images are even more harsh/extreme with colors all over), however with the U340-on-flash + UV/IR-Cut-filter-on-lens, the red is subtle and without any harsh effect.

 

[Pylon]

Common Xenon flash tubes have only 2% uv.

 

So I use a modified Metz 45CT1 (150Ws) and a Norman 200B (200Ws) and a homemade unit (180Ws) at close distances to get some uv onto my stones:

 

 

Is the Canon 199A xenon? What is the Metz 45CT1 made from?

 

What are you using to filter your lights?

[colinbm]

Great work Stefan

Col

[baffe]

Thanks Colin!

 

I only shoot FL, phosphorescence and use a Baader "UV/IR cut L" on the lens. The Norman and the homebrew unit is filtered with UG1, the Metz has a double layer of the UGxy glassblowers blacklight tube.

 

Here the results, Wermerite in daylight, it's flourescence and it's phosphorescence:

 

http://up.picr.de/23568912zu.jpg

[colinbm]

That is a good glow in the rock Stefan

Col

[JCDowdy]

To filter the 199A you can either use the Baader-U at the end of a funneled snoot made from step up/down rings, or you can use uviroptic's rectangular filter set. I taped the filters together on the edges only using scotch tape (which I think actually absorbs UV light) then placed it in the rectangular black frame and fit perfectly.

 

Where exactly did you fit these filters, inside the frame that screws onto the 199 to hold the Fresnel or into the frame that holds the slide on diffuser?

[Pylon]

in the slide diffuser

[Pylon]

Metz 45CT1 has a very simple circuit. Easy to modify, easy to repair. Only one main reflector.

 

Metz "45CL4" has SCA-control, low tigger votage, a second small reflector (wich most photograhers don't use) has a control circuit for analoque (real!) TTL. While "45CL4 digital" can perform E-TTL (Canon) and i-TTL (Nikon) control for dslr's.

 

I only have experience with 45CT1.

 

I'm now thinking about getting one of these because it seems like it is brighter than the 199A. Based upon what you do know on either of them, would you recommend one over the other? Besides the high voltage (which could be resolved using a Wein safe sync), It sounds like electronics in the 45CT1 needs to be repaired more often; maybe the 45CL4 improved in that area and would be the choice to get, for a non-electrician like myself?

[baffe]

>I'm now thinking about getting one of these because it seems like it is brighter than the 199A.

 

I never tested that! But it has about 110Ws... I don't have a 199A

 

>Based upon what you do know on either of them, would you recommend one over the other?

 

The later versions of 45CXYZ like45CL4 are better. And all my 45CT1 suffer from defective capacitors. They are something round 40 Years now. Because of the high operating voltage (365VDC and more) of this "metzens" common capacitors (330-350VDC) don't work.

 

> Besides the high voltage (which could be resolved using a Wein safe sync),

 

I use optical slave triggers. But i never had any flash with high trigger voltage that didn't work with weinsync.

 

> It sounds like electronics in the 45CT1 needs to be repaired more often;

 

No, I just modify that for my purposes.

 

>maybe the 45CL4 improved in that area and would be the choice to get, for a non-electrician like myself?

 

Better choice in any way!

[JCDowdy]

I'm now thinking about getting one of these because it seems like it is brighter than the 199A. Based upon what you do know on either of them, would you recommend one over the other? Besides the high voltage (which could be resolved using a Wein safe sync), It sounds like electronics in the 45CT1 needs to be repaired more often; maybe the 45CL4 improved in that area and would be the choice to get, for a non-electrician like myself?

I have both the 199A and the 45CT1+Wein safe sync and my impression is there in not a lot of difference. I was actually a bit disappointed expecting the big old Metz to be noticeably brighter in the UV. Perhaps my CT1 is not putting out like it should or I just have not gotten the setup right. Ergonomically however, the 45CT1 may be more versatile, especially used hand held off camera.

[Pylon]

You should figure out if both flashes are set to full power by doing tests, then show us a UVIVF comparison with both flashes set to full power, and the same settings on the camera! We could see if there is a large difference or not. Shouldn't take more than 10 minutes! :)

[Andrea B.]

EDITOR'S NOTE: Some eye safety posts in this thread were split off and added to the eye safety thread

UV and Your Eyes :: UV Safety Reference

 

Let's keep this thread about the specifications and usage of UV flashes.

Thanks !!!