Trying out a new spectrometer

[AKReefing]

I ordered a new Spectryx spectrometer as an experiment. It's not a very old model, but it looks like the company may have gone under. Their web domain is no longer in use. It comes with a fiber optic cable, USB cable and software, so I'm hopeful. The specs claim 1.5nm accuracy, and a range of 400-800nm (claims 350-850 typical).

 

[Reef-Engineer]

That would be fun to test fixtures with to keep manufacturers honest!

 

[AKReefing]

Definitely want to test again knowns. I'm sure they're accurate. It's the less known systems that might be questionable.

 

[AKReefing]

Definitely want to test again knowns. I'm sure they're accurate. It's the less known systems that might be questionable.

Sorry. "Against" knowns.

 

[AKReefing]

The first shipment was lost by USPS en route. After some insistence from me on a replacement, and complaining by the seller that they're losing money on the deal, they shipped a replacement.
I also ordered an older model Ocean Optics spectrometer to experiment with.

 

[AKReefing]

Ok, the Spectryx arrived today. Here's what it looks like. It's SMALL! Based on that alone you'd think it's junk. You'd be wrong.

It's tiny, but it's extremely accurate. The app that comes with it is a bit odd. It requires that I select a Com port in the app, but that's really easy, because there's only one available. I took a measurement of a fluorescent bulb and compared it to one taken by an Ocean Optics HR2000 spectrometer. https://en.wikipedia.org/wiki/File:Fluorescent_lighting_spectrum_peaks_labelled.gif

File:Fluorescent lighting spectrum peaks labelled.gif - Wikipedia

Here's what the Spectryx graph of the fluorescent bulb looks like. You manually click on what you see as the peaks, and it tells you the wavelength. I did that for eight peaks before referencing the Wikipedia article above. That gives me high confidence that the Spectryx measurements I've made are very accurate.

My measurements using Spectryx are, in my opinion, absolutely dead on from 400nm through over 800nm. I mean to within a nanometer. I'm really impressed.

 

[AKReefing]

Based on the comparison of the Spectryx to the full visual range of measurements made by the Ocean Optics HR2000 spectrometer used in the Wikipedia article, I'm confident in the accuracy of the Spectryx for my personal purposes. I'm not saying it's as good as an expensive $thousand-plus spectrometer, but in this case I'm very happy with it--beyond surprised.

Now let me compare it to the PARwise.

Although I've verified the Spectryx's accuracy from 400-800nm, my focus in the hobby is in the range from 550nm to around 470nm for my LEDs. I measured five violet and blue LEDs with the Spectryx and PARwise, putting the sensor for each within an inch of the LEDs. One positive with the PARwise is that the readings were rock solid for wavelength. Once it settled on a wavelength it never budged. The Spectryx was also, but I had to hold the end of fiber optic cable very still.

So here are the actual measurements. Only one LED had similar measurements:
PARwise Spectryx
450 459
446 453
440 442
384 404
423 433

Based on the earlier comparison, I'm calling the Spectryx measurements "truth", and PARwise "fiction".

I disagree with the ITC statement that "[PARwise] gives you all of the relevant lighting measurements required to make informed decisions." The only informed decision I'm thinking about making is returning it for a refund.

 

[Nonya]

Based on the comparison of the Spectryx to the full visual range of measurements made by the Ocean Optics HR2000 spectrometer used in the Wikipedia article, I'm confident in the accuracy of the Spectryx for my personal purposes. I'm not saying it's as good as an expensive $thousand-plus spectrometer, but in this case I'm very happy with it--beyond surprised.

Now let me compare it to the PARwise.

Although I've verified the Spectryx's accuracy from 400-800nm, my focus in the hobby is in the range from 550nm to around 470nm for my LEDs.

Do you plan to measure the UVA range?

 

[AKReefing]

Do you plan to measure the UVA range?

Sure, if I can find some actual UV LEDs.

 

[AKReefing]

Here are the comparisons between Spectryx and PARwise for the same fluorescent light. The PARwise also said the peak wavelength is 580nm, which is the result of a smoothed curve, while the Spectryx identified the peak as 546nm, which is one of the mercury peaks. Other than pretty colors, I don't see how the PARwise can provide any useful data.

 

[AKReefing]

@telegraham
See above.
I'm also looking at getting an old Spectral Products spectrometer to play with. Even used they're not all that cheap, but I can always resell it when I'm done comparing it with other spectrometers. If the Spectryx compares favorably I'll decide which to keep.

 

[oreo54]

Sure, if I can find some actual UV LEDs.

Ultra Violet 365nm - UVA 3W LED-8794102402

www.stevesleds.com

Lifespan - Rated at 1,000 hours minimum, although we have been testing them for more than a year and have some running for more than 5,000 hours now.

 

[AKReefing]

Ultra Violet 365nm - UVA 3W LED-8794102402

www.stevesleds.com

Too far left for me. I'm thinking 370 or higher to 1) test the spectrometer range/accuracy, and 2) to assemble a group of LEDs that will contribute to fluorescence--not so much to photosynthesis.

 

[oreo54]

Too far left for me. I'm thinking 370 or higher to 1) test the spectrometer range/accuracy, and 2) to assemble a group of LEDs that will contribute to fluorescence--not so much to photosynthesis.

395nm LUXEON Z Ultraviolet LED on a Saber Micro-Z1 5mm Square Base - 625 mW @ 500mA

The Quadica Developments SM-01-U5 is no longer available, but our SM-01-U3 may be a suitable replacement. Order online now. No minimums. Shipping Anywhere.

luxeonstar.com

Pricy (some)..

LUXEON Z 5mm Square LED Modules by Luxeon Star LEDs

The ultra-small Micro-Z1 high-power LUXEON Z LED modules are the smallest LED modules available that can be worked with using standard benchtop tools and hand soldering techniques. All colors, no minimums, worldwide shipping.

luxeonstar.com

 

[telegraham]

@AKReefing ... order this and share your peak results. https://a.co/d/0vBrmhX It's cheap.

@luxdium maintains a spreadsheet with data from multiple spectrometers, including mine.

 

[AKReefing]

@AKReefing ... order this and share your peak results. https://a.co/d/0vBrmhX It's cheap.

@luxdium maintains a spreadsheet with data from multiple spectrometers, including mine.

Submersible? Is it neon or something?

 

[AKReefing]

@AKReefing ... order this and share your peak results. https://a.co/d/0vBrmhX It's cheap.

@luxdium maintains a spreadsheet with data from multiple spectrometers, including mine.

Does he share the spreadsheet?

 

[AKReefing]

395nm LUXEON Z Ultraviolet LED on a Saber Micro-Z1 5mm Square Base - 625 mW @ 500mA

The Quadica Developments SM-01-U5 is no longer available, but our SM-01-U3 may be a suitable replacement. Order online now. No minimums. Shipping Anywhere.

luxeonstar.com

Pricy (some)..

LUXEON Z 5mm Square LED Modules by Luxeon Star LEDs

The ultra-small Micro-Z1 high-power LUXEON Z LED modules are the smallest LED modules available that can be worked with using standard benchtop tools and hand soldering techniques. All colors, no minimums, worldwide shipping.

luxeonstar.com

Here's the recurring theme. Unless these vendors actually measure the wavelength of each emitter using a calibrated spectrometer, how can we trust that an LED labeled as 395nm is truly 395nm?

 

[oreo54]

Here's the recurring theme. Unless these vendors actually measure the wavelength of each emitter using a calibrated spectrometer, how can we trust that an LED labeled as 395nm is truly 395nm?

Well yea, even the manuf doesn't guarantee 1 nm accuracy..

 

[AKReefing]

Well yea, even the manuf doesn't guarantee 1 nm accuracy..

+/- 5nm--a 10nm window can be met with pretty much any spectrometer of any quality.