Jump to content
UltravioletPhotography

UV 365nm LED Light


colinbm

Recommended Posts

This UV 365nm LED light is advertised in eBay Australia.

7W-25-LED-365nm-UV-Light-Bulb-AC100V-240V-A19-Ultraviolet-Blacklight-with-E9M8.

I have asked the seller to assure me that it is 365nmm & they said it is.

Does anybody know this light Please ?

post-31-0-74736600-1568291684.jpg

Link to comment

That looks similar to my 365nm led bulbs, I got from Amazon:

Lixada 7W 25 LED 365nm UV Light Bulb AC100V-240V A19 Ultraviolet Blacklight with E27 Lamp Base

 

Mine are 365nm.

 

https://www.google.com/url?sa=t&source=web&rct=j&url=https://www.amazon.com/Lixada-AC100V-240V-Ultraviolet-Sterilization-Fluorescent/dp/B06XKS9KRK&ved=2ahUKEwiywpv65MvkAhXyt1kKHas0Ar0QFjAAegQIBhAB&usg=AOvVaw3BhYLEUpUCqxS6gwlLHsTp&cshid=1568308747553

 

Link to comment

Well, isn't that an interesting bulb! That's the first UV-Led bulb I've seen. I think I'll skip this one for bedside reading though. :grin:

 

I'm always a bit surprised that 365 nm is offered for a blacklight used at parties or whatever. Seems like it would be much better for the eyes to use a 385 nm blacklight, don't you think?

 

We now have some visible UV-Led light bulbs in a few lamps. I like them because they do not get hot so the lampshade stays nicer longer. And you don't scorch your fingers turning off the light.

Link to comment

Not sure if enough 385nm is safe enough for your eyes. 405nm and 435nm have been subjects to cause eye problems.

The 365nm are usually indicated for curing or sterilization. However, they will not sterilize much and don't use them for that. Curing maybe, I don't know.

 

Even 254nm I still have my doubts for sterilization. I really don't think it to be cost effective. Would need to see controlled study. I think they should be labelled as disinfectant. Kind of like vaporized hydrogen peroxide. Might be lucky if you killed a thin surface layer of something.

Link to comment

Thanks Andrea & dabateman

Yes that is exactly the same photos in the advertising on eBay & Amazon.

I have one coming so I will see how it goes & may order some more ?

There are some other interesting LEDs on offer from Amazon too, good to see.

Cheers

Col

Link to comment

Not sure if enough 385nm is safe enough for your eyes. 405nm and 435nm have been subjects to cause eye problems.

The 365nm are usually indicated for curing or sterilization. However, they will not sterilize much and don't use them for that. Curing maybe, I don't know.

 

Even 254nm I still have my doubts for sterilization. I really don't think it to be cost effective. Would need to see controlled study. I think they should be labelled as disinfectant. Kind of like vaporized hydrogen peroxide. Might be lucky if you killed a thin surface layer of something.

I don't properly understand this 'killing' of bugs ?

Is it just sterilization so they can't reproduce ?

Col

Link to comment

I don't think they understand it either.

A bug zapper, in the large insect type. Would use an electric ark, basically electrocution to kill. The light just attracts the insect to their electric death.

In the small, bacterial, mold, yeast bug world. It may cause some DNA damage and may limit reproduction. But don't bet on it. Bacteria form biofilms that keep them alive bellow the crust. And yeast will spore into a dry like pellet to keep and come back again.

If you want to kill some small bugs, moist hot steam, like in an autoclave is still the best.

Link to comment

No, at 254nm, the light can cause actual cell death. Sunburn in humans, probably would do in any single-celled animal. Obviously intensity matters here.

 

ETA: wait, do you mean BACTERIA or INSECTS?

Link to comment

No, at 254nm, the light can cause actual cell death. Sunburn in humans, probably would do in any single-celled animal. Obviously intensity matters here.

 

ETA: wait, do you mean BACTERIA or INSECTS?

 

Nope,

You will always, if you look hard find a bacteria resistant. Here is a review looking at some resistance:

https://www.ncbi.nlm.nih.gov/m/pubmed/18627518/

 

In an other study I quickly found, a single mono layer of cells were killed using 254nm. However, increasing that to just 4 cells required at least 10x more 254nm light exposure to kill.

Bacteria films are much more than 4 cells thick.

 

 

Link to comment
Isn't the 254 nm level used mostly for water purification? I don't think it would be much use on bioflims either (like those spectacular bacterial layers in Yellowstone hot springs).
Link to comment

Burkholderia cepacia complex, a common water bacteria does seem to be sensitive to 254nm light.

But I still wouldn't trust that, as its not the only problem in your water. Its also easier to just filter your water or boil it to be sure. Hot water tanks in the US are usually 140F, 60C. But even at that temperature you can have stuff growing.

Geobacillus stearothermophilus is very happy at 55C to 60C.

 

But back to your 365nm photography bulb.

I cut the pastic dome about 5mm from the base and use tape to add a 55mm to 52mm step ring to add filters.

Link to comment

But back to your 365nm photography bulb.

I cut the plastic dome about 5mm from the base and use tape to add a 55mm to 52mm step ring to add filters.

 

Wow you filter it too....

Do you know what the transmittance of the lamp or LEDs are please ?

Col

Link to comment

I don't know it exactly but this should help:

 

This is 1000 lines/mm image of my 405nm Black light LED bulb:

post-188-0-78104900-1568457867.jpg

 

This is 1000 lines/mm image of my 365nm LED bulb:

post-188-0-12527700-1568457881.jpg

 

This is not filtered, the yellow part would be into 370nm, the blue part may go into 400nm. The cool thing is all LEDs on this bulb are matched. No cheating with different peak ones.

 

I don't know it exactly but this should help:

 

This is 1000 lines/mm image of my 405nm Black light LED bulb:

post-188-0-78104900-1568457867.jpg

 

This is 1000 lines/mm image of my 365nm LED bulb:

post-188-0-12527700-1568457881.jpg

 

This is not filtered, the yellow part would be into 370nm, the blue part may go into 400nm. The cool thing is all LEDs on this bulb are matched. No cheating with different peak ones.

 

The peaks seem to match 370nm, just like the Convoy 365nm led flashlight.

Link to comment

I mostly don't filter it as I like the UV/vis colors. But I have added a polarizer to my bulbs to play with polarized light.

I also just got two ZWB1 filters for my lights, which end up being 1.9mm thick. They go a little further into blue than my older ZWB1 filter, which is 1.8mm thick. But none of them go as far into blue as a Baader venus filter. Also my newer ones have much less IR through. So glass maybe better. The exposure time on the new ones is the same as my old one. In that test I got 1.6 sec for Baader, 2.5 sec for all ZWB1 filters and 3.2 sec for 2mm U340 filter which didn't have any blue.

 

I will use these just to be sure no visible leak for some UVIVF I want to play with.

Link to comment

Please sign in to comment

You will be able to leave a comment after signing in



Sign In Now
×
×
  • Create New...