Sciencemadness Discussion Board

Desktop Spectrometry Kit

blogfast25 - 26-5-2014 at 06:36

From what I understand (?) these desktop spectrometers have only just begun shipping:

http://store.publiclab.org/products/desktop-spectrometry-kit

Does anyone here have one yet or plan on buying one?

unionised - 26-5-2014 at 06:46

I'm tempted to get one just for the software + compatible camera.

Bert - 26-5-2014 at 06:47

Yay! Tricorder smartphones, here we come!

Additional thought:

If the NSA/whoever gets to backdoor and use all our portable electronics for data collection at will, they could all do with some basic chemical and radiological measurement hardware...

The Volatile Chemist - 26-5-2014 at 07:55

And... YES! They're on Amazon! I may get one yet!

http://www.amazon.com/PublicLab-Desktop-Spectronomy-Kit/dp/B...

The only question is the price... It looks a bit cheap for $40 and it's even more on amazon. Ouch...
Also, do you think this'll work/work well? What about the software for it? Does it have a good enough res. for chemistry applications? It claims something like 3nm...?

Edit: It's the same as:
http://www.scientificsonline.com/desktop-spectronomy-kit.htm...

[Edited on 5-26-2014 by The Volatile Chemist]

Rogeryermaw - 26-5-2014 at 08:21

check this one out. sounds neato for 12 bucks but is it worth a cent?

http://www.amazon.com/Scientifics-Online-Foldable-Smartphone...

[Edited on 26-5-2014 by Rogeryermaw]

smaerd - 26-5-2014 at 08:21

I heard of this project maybe a year ago. I wasn't very impressed, the design itself could be created incredibly cheaply, and the resolution last time I checked wasn't really very adequate for what I would want a UV-VIS for. Rather shell out the additional 60$ and opportunistically scoop a used instrument off of e-bay then pay 70$ for cardboard and some grating film(0.50$). Or 40$ for a chunk of a CD and some kind of repurposed wall out-let case with a web-cam module. I've seen Spec20's in like new condition for 100-150$ on ebay from time to time.

It's a cool idea though I hope it develops.

[Edited on 26-5-2014 by smaerd]

blogfast25 - 26-5-2014 at 10:05

Quote: Originally posted by The Volatile Chemist  

The only question is the price... It looks a bit cheap for $40 and it's even more on amazon. Ouch...

Also, do you think this'll work/work well? What about the software for it? Does it have a good enough res. for chemistry applications? It claims something like 3nm...?

[Edited on 5-26-2014 by The Volatile Chemist]


$40 is too expensive for you? Ain’t no pleasing some people! ;)

See also calibrating it:

http://publiclab.org/wiki/spectral-workbench-calibration
Quote: Originally posted by Rogeryermaw  
check this one out. sounds neato for 12 bucks but is it worth a cent?

http://www.amazon.com/Scientifics-Online-Foldable-Smartphone...

[Edited on 26-5-2014 by Rogeryermaw]


Designed by the same wiki group, that one.
Quote: Originally posted by smaerd  
I heard of this project maybe a year ago. I wasn't very impressed, the design itself could be created incredibly cheaply, and the resolution last time I checked wasn't really very adequate for what I would want a UV-VIS for.

[Edited on 26-5-2014 by smaerd]



Then you’re hard to impress, I guess. I appreciate the question about purpose though. Simple emission spectrometry is what I’d use it for. Having the ‘luxury’ to identify strong lines by wavelength and without further ado is well worth the money, IMHO. That's assuming it's light sensitive enough...

What would be your purpose?

smaerd - 26-5-2014 at 10:24

Reliable quantitation, perhaps kinetics. For emission spectrometry it's probably great for the cost.

It doesn't touch UV, which is fine but something I would want. Don't get me wrong it's a good idea, and highly portable. I just don't think it's good enough for bench purposes. For the price and what it is I think it could be built pretty simply with change to spare, haven't bothered to check though. Keeping in mind this also must still be assembled and is a kit. I was also hard pressed to find information about the instruments limitations. "Can be as good as less then 3nm spectral resolution" is pretty vague. There's no heat compensation, or beam referencing, any of that. Not even a light source, which sure isn't a big deal with the calibration I guess if the light source used is known. What's the maximum intensity for the camera module? IE: Can I fry it by over-loading it?

Again don't get me wrong, these CCD type spectrometers are pretty wonderful as far as I am concerned. Not much beats a broad wavelength measurement 'all at once' for simplicity. For example the expensive, ocean optics USB-ISS module operates on similar principles. However, it offer's a much finer resolution, greater spectral band, solid enclosure, and well an actual circuit to handle some of the things a spectrometer probably 'should'.

Again awesome for quick field work, would I trust it with something more involved, I am not convinced yet. Do I support the work these people have put into it, yes, just not monetarily.

edit - From an educational stand-point it's pretty great. Huge leap from those cheap plastic hand-held spectrometers in a big way.

[Edited on 26-5-2014 by smaerd]

The Volatile Chemist - 26-5-2014 at 11:06

Exactly. It's nice, cheap - I admit, $40 is fine for a DIY spectrophotometer, but with what they include and it's res. I doubt it's worth the $60 on amazon for it. It doesn't look like it's made of anything nice, I could probably do the same they did. I'd rather have one already built and more expensive, because it'd be worth it's price. This is just a box of stuff I could buy myself, so why pay shipping?

blogfast25 - 26-5-2014 at 12:14

Quote: Originally posted by smaerd  
Not even a light source, which sure isn't a big deal with the calibration I guess if the light source used is known.


They recommend a saver bulb (for the main Hg lines) or any light source with two known lines. See the calibration page I linked to above.

As regards: "I've seen Spec20's in like new condition for 100-150$ on ebay from time to time.", great as the Spec 20s are, we're really comparing apples and oranges here.
Quote: Originally posted by The Volatile Chemist  
This is just a box of stuff I could buy myself, so why pay shipping?


Not quite. Thought has gone into designing this thing. Having access to that know how is worth $40 to me. Trust me, I’ve built several homemade spectrometers (but with naked eye, not electronic detection) and it takes time and know how to get it right. They’ve done all that for us. The simple math of a reflecting diffraction grating alone is above the math capability of most people.

Also, paying for it helps these projects being further developed.

But if you really think it’s that easy, go ahead and report it here! ;)


[Edited on 26-5-2014 by blogfast25]

HeYBrO - 26-5-2014 at 13:21

Are you going to purchase one Blogfast? I think its an interesting design and for $40 i hardly see what could go wrong.

blogfast25 - 27-5-2014 at 12:54

Quote: Originally posted by HeYBrO  
Are you going to purchase one Blogfast? I think its an interesting design and for $40 i hardly see what could go wrong.


I'm very much that way inclined. Lack of time will probably mean it will take a while yet.

pichoro - 27-5-2014 at 12:59

I think I may purchase one at the end of summer. I'm very much interested. I've already had thoughts about buying an "aquafarm" for a year long experiment for my students, and can see this being an excellent expansion on that plan. And I've got the extra money in my budget to spend on it.

Aquafarm: https://www.backtotheroots.com/shop/aquafarm