Close look on UV LEDs

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Lexel
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Close look on UV LEDs

Did some photos with my reverse adapter for DSLR
Used Canon Eos 50D with 16-35mm F2.8 lens
@F=18 and reverse adapter ISO400 1/160s
light with a 1400 lumens 5000K NW flashlight from the side

First Lite On

http://www.mouser.com/ds/2/239/LTPL-C034UVH365%20DataSheet_Ver4_20150916...
this LED has a electrical neutral middle thermal pad for DTP stars
The active area is a lot bigger than on he Nichia LED, so it throws less
my LED has a surprizing low forward voltage of 3.46V @0.7A

second Nichia NCSU276A U365

die size 1×1mm
LED forward voltage of my one 3.84V @700mA
http://www.nichia.co.jp/specification/products/led/NCSU276A-E.pdf

Edited by: Lexel on 04/24/2017 - 22:08
Valor
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Are you going to de-dome them? Cool

Lexel
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the pictures are only cropped a tiny bit to cut parts from background, the original size has about 13MP from 20MPixel left

for those who are not familiar how to do ultra macros with reversing a lens

This reverse adapter is self build from
first a reverse adapter without any contacts
like this http://www.ebay.com/itm/72-MM-72MM-Macro-Reverse-Lens-Adapter-Ring-For-C...
a adaptor ring extending from 72 to 82mm for the lens

Then I ordered a cheap macro extender for EF lenses
dismantled it to get the Ring connecting to the lens to the camera
on the other side I removed the contact plate

I used a cable to connect the both contact plates

Then I dremeled the mechanical reverse adapter to make the contact plate fir and hot glued in there

It was a selfbuild back in 2008 or so
for those who dont want to self build them they are now also commercial availiable
http://www.ebay.com/itm/AF-Macro-Reverse-Adapter-for-Canon-with-58-67-72...

itsonlyme
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Ingenious and amazing quality

mrheosuper
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Why need a contact, doesn’t you have to use mf(AF when shot macro really suck)

Forgot my pen

turboBB
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That is awesome Lexel!  Do you by any chance know if they make equivalent of that AF adapter for Nikon F mount? I did a search but came up empty.

LatticeBlight
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Wow, the lighting really makes the difference. I have the choice of macro tubes, macro lens and one of those glass filters but it never turns out as good since my iso shoots up to 1600+.

Lexel
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Improoved the resulution with a extender
Pictures cropped in full resolution

The IR Osram LED is hard to photograph as its dome is really high and acting as a very strong lens

djozz
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Very nice pictures Lexel!

Lexel wrote:
First Lite On


this LED has a electrical neutral middle thermal pad for DTP stars
The active area is a lot bigger than on he Nichia LED, so it throws less
my LED has a surprizing low forward voltage of 3.46V @0.7A

Hmm, that makes me think, the latest LiteOn 365nm that I received from TME have the same appearance as yours, and the triple that I built with them drew way more current than I expected (and hoped for).

The LitOn led that I tested a hear ago however had a different die, other pattern and not that rainbow look. It must then not just be the looks then, the performance has changed too. At least the voltage has become lower and I wonder about the output, it is still good but is it more or less? Here’s the picture of the LiteOn led that I tested: