Alternative chemical sensors, such as webcam spectroscope

katonafull

rsevs3 wrote:

That is awesome katonafull! Watching with a huge amount of interest.

Will definately like to have a play with this and i have the same webcam sitting next to me. But for now i have to fix my phone, because i cant help but change the android version every 5 minutes and now it is broken

The world has already endured without webcamspectroscope sensor, we have time yet!

good luck!

SuperVeg

rsevs3 wrote:

That is awesome katonafull! Watching with a huge amount of interest.

Will definately like to have a play with this and i have the same webcam sitting next to me. But for now i have to fix my phone, because i cant help but change the android version every 5 minutes and now it is broken

bricked ?

DuiNui

I've done a little digging around on this.
Most CCD arrays, such as those used in phones and digital cameras are pretty sensitive in the Ir range, but the raw output is in RGB format, which allows up to about 700nm, i.e. visible red, why would they waste bandwidth on frequencies invisible to humans.

To do anything accurate you would really need to get pre-processed data from the array, or forget the webcam and buy a dedicated IR or NIR CCD array.

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rsevs3

SuperVeg wrote:

rsevs3 wrote:

That is awesome katonafull! Watching with a huge amount of interest.

Will definately like to have a play with this and i have the same webcam sitting next to me. But for now i have to fix my phone, because i cant help but change the android version every 5 minutes and now it is broken

bricked ?

Nope

managed to save it... again... :headbang:

DuiNui wrote:

I've done a little digging around on this.
Most CCD arrays, such as those used in phones and digital cameras are pretty sensitive in the Ir range, but the raw output is in RGB format, which allows up to about 700nm, i.e. visible red, why would they waste bandwidth on frequencies invisible to humans.

To do anything accurate you would really need to get pre-processed data from the array, or forget the webcam and buy a dedicated IR or NIR CCD array.

This is something i was thinking about too. Much like a phone line. I just didnt know how to put it into words nicely

katonafull

Ohh f.ck... i got an information...
the chemicals, that we want to measure aren't show optical effect like light absorption.

But I don't understand...because the mentioned method above about the Laser and spectroscope...to ammonia...it works
and it based on light absorption.

all the same
it doesn't matter, because we can use to other materials too

Ok. Sumarized!

I think
We need a table, that show...which materials show light absorption.
Some materials from those need IR ccd, but not the all...

I will make the Big Black Box Webcam Spectroscope with Artifical Light =BBBWSAL= 3xBWSAL

with a webcam
And i Will test that..than if we need, i change, or complete the webcam an IR array

opinion? is it correct?

rsevs3

One thing i noticed is that they were measuring ammonia in the air. I dont know how that would translate to water...

I watched a video about spectroscopy yesterday about determining atmospheres of other planets. It was incredibly complex.

Ao+

I think it's impossible to make that sensor.
It's impossible like MRI, xerox, air plane, ball point pen, etc.

katonafull

Every complicated things begin like an easy idea.
/ The ball point pen is a hungarian invention

)) /
and the complicated thing sometimes convertabled to an easier thing.
I will try this sensor, if i have free time.

I believe in the creative power of mind, and I also know that nothing is impossible.
Although I know that almost no chance, so i need a lot of perseverance, encouragement, spiritual and mental support, including the negative criticism.

But i never will accept the expressions like: it won't succeed.

If it don't work with Nh3/4, No3...it will work with iron...or anythíng

I will try it, and if it won't work, i played a good one, and i win some experience.

If you see, tell what the mistake in the plan, but please don't emit negative energy. Thanks!

Ao+

I like that attitude.

keith

hooked

I agree with you katonafull. Good luck.

Can you explain what you meant by 'the chemicals, that we want to measure aren't show optical effect like light absorption.', do you mean in the visible region?

I thought all elements had a spectra as the spectra relates to the elements interaction with light.

DuiNui

Indeed.
Look these guys did it in 1934.
http://adsabs.harvard.edu/abs/1934PhRv...45..234C

Maximum absorption of Ammonia is at 1.25cm, in the microwave range!!!
I haven't looked into it much, but to measure it with a laser at NIR/IR frequencies.
I see frequent mentions of "Vibrational overtone Absorption" and "Photo Acoustic"
Don't really (or at all) know what this is, but I'm guessing something similar to harmonics.
Excitation at a certain frequency causes secondary/tertiary etc. overtones at different wavelengths.

So I am guessing a very powerful IR laser is used, as the absorption at IR wavelengths is going to be very small.
In early Ammonia experiments they were using microwave generators that had to be shielded and used special diffraction gratings.

All very interesting stuff, though I don't think I want to make a microwave generator

BullwinkleII

Lots of kitchens have one handy.

Of all the wavy things, microwaves are pretty easy to handle.

DuiNui

Well yes.
But my point was that would you really want to be playing around with a self modified microwave?
This years blockbuster movie from Thailand...
"Honey I Cooked the Kids"

BullwinkleII

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