Author Topic: Weak DyI emission in my Aliexpress 70W 6500K MH lamp  (Read 143 times)
dor123
Member
*****
Offline

Gender: Male
View Posts
View Gallery

Other loves are printers/scanners/copiers, A/Cs


WWW
Weak DyI emission in my Aliexpress 70W 6500K MH lamp « on: December 31, 2025, 12:16:11 PM » Author: dor123
I bought a new 6500K 70W MH lamp for my tracklight several weeks ago, and its DyI emission is very weak, even today. And no, it have a good amount of halides inside and large enough heat reflective coatings at the arctube ends, and operates on an electronic HID ballast.
Why the DyI in my lamp is so weak?
Logged

I"m don't speak English well, and rely on online translating to write in this site.
Please forgive me if my choice of my words looks like offensive, while that isn't my intention.

I only working with the international date format (dd.mm.yyyy).

I lives in Israel, which is a 220-240V, 50hz country.

Laurens
Member
*****
Offline

View Posts
View Gallery

Re: Weak DyI emission in my Aliexpress 70W 6500K MH lamp « Reply #1 on: December 31, 2025, 04:25:30 PM » Author: Laurens
How do you decide what's weak?

Did you let it run for 100 hours before taking your first spectrum? The first 100 hours are not representative for what a discharge lamp should look like. It has to age 100 hours first, because in the first 100 it ages rapidly after which it stabilizes for thousands of hours.
Logged
dor123
Member
*****
Offline

Gender: Male
View Posts
View Gallery

Other loves are printers/scanners/copiers, A/Cs


WWW
Re: Weak DyI emission in my Aliexpress 70W 6500K MH lamp « Reply #2 on: December 31, 2025, 09:05:06 PM » Author: dor123
I bet the lamp run more than 100 hours. I received the lamp at 20.12.2025.
« Last Edit: December 31, 2025, 09:25:57 PM by dor123 » Logged

I"m don't speak English well, and rely on online translating to write in this site.
Please forgive me if my choice of my words looks like offensive, while that isn't my intention.

I only working with the international date format (dd.mm.yyyy).

I lives in Israel, which is a 220-240V, 50hz country.

RRK
Member
*****
Offline

Gender: Male
View Posts
View Gallery
Roman


Re: Weak DyI emission in my Aliexpress 70W 6500K MH lamp « Reply #3 on: Today at 04:31:53 AM » Author: RRK
So you wanted a 6500K lamp and Chinese bro's supplied you with Dy-Tl lamp accordingly, okay. ) Tl line is always very prominent in these, as it is essentially monochromatic even at high arc loadings. It may look bright on the spectrum, but overall energy is limited as the width is still very narrow.


If checked with a calibrated spectrometer the lamp will show the color on CIE1931 XY space goes too much high to the green, we may speculate the lamp is improperly dosed or runs too cold (due to a leak to outer bulb, just badly made etc).


Logged
dor123
Member
*****
Offline

Gender: Male
View Posts
View Gallery

Other loves are printers/scanners/copiers, A/Cs


WWW
Re: Weak DyI emission in my Aliexpress 70W 6500K MH lamp « Reply #4 on: Today at 06:24:51 AM » Author: dor123
There is no thallium in the spectrum. Only mercury and dysprosium. The green line is of mercury.
« Last Edit: Today at 07:20:14 AM by dor123 » Logged

I"m don't speak English well, and rely on online translating to write in this site.
Please forgive me if my choice of my words looks like offensive, while that isn't my intention.

I only working with the international date format (dd.mm.yyyy).

I lives in Israel, which is a 220-240V, 50hz country.

RRK
Member
*****
Offline

Gender: Male
View Posts
View Gallery
Roman


Re: Weak DyI emission in my Aliexpress 70W 6500K MH lamp « Reply #5 on: Today at 07:20:19 AM » Author: RRK
How do you know this? Tl 535nm is rather close to Hg 546nm, hard to tell on uncalibrated spectrum. One way to tell is to look at run-up. At start, only four Hg lines present, as the burner heats, nearby Tl green line appears, and later usually over-dominates green Hg line.

Logged
dor123
Member
*****
Offline

Gender: Male
View Posts
View Gallery

Other loves are printers/scanners/copiers, A/Cs


WWW
Re: Weak DyI emission in my Aliexpress 70W 6500K MH lamp « Reply #6 on: Today at 07:21:22 AM » Author: dor123
No thallium appears when I see the spectrum of this lamp run-up. Also, the yellow doublet and blue line of mercury are also strong.
Also: The lamp would be greenish if thallium would be present, and it isn't the case.
Logged

I"m don't speak English well, and rely on online translating to write in this site.
Please forgive me if my choice of my words looks like offensive, while that isn't my intention.

I only working with the international date format (dd.mm.yyyy).

I lives in Israel, which is a 220-240V, 50hz country.

Print 
© 2005-2026 Lighting-Gallery.net | SMF 2.0.19 | SMF © 2021, Simple Machines | Terms and Policies