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File: s2JgRCX.jpg (31 KB, 500x375)
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Hey /p/, I need to take pictures of just a specific part of the spectrum.
Specifically, 650-780nm.
Is this what a filter does? I know nothing about cameras.

I found this that I can set it to a specific wavelength? Or is it more of a cutoff?
https://www.amazon.com/Fotga-Adjustable-Infrared-X-Ray-Filter/dp/B016Y4BTXC
>>
>>3310534
Most filters only exclude frequencies above or below a certain wavelength.
You'd have to use a combination of cutoff filters or find a bandpass filter for your purposes.
Try looking for a deep red/IR filter or something.
>>
>>3310575
So I just stick two filters together basically? One that has a low cutoff and one thst has a high cutoff, and I get what overlaps?

>>3310578
My results? I'm using it to detect fluorescence of plants, I guess I could post pics if it works
>>
>>3310590
>and I get what overlaps?

Yes
>>
>>3310590
>I'm using it to detect fluorescence of plants

It might be easier for you to just filter your light source.
>>
>>3310609
Can't filter the sun, but I may have to do it at night if I can't get anything.
I'm going to be lighting the plant with a 405nm laser, which should cause it to fluoresce light in the range in op post. In theory anyway.
>>
>>3310611
I see.
Can't you take a trimming of the plant and illuminate it with your LASER in a dark room, eliminating the need for a filter?
>>
>>3310613
I'd have to filter the laser wavelength out, but I can do that.
It's not really in line with what I'm doing this for, but if I have to I can, it's just a proof of concept
>>
>>3310616
laser light is already monochromatic
>>
>>3310616
As a proof of concept, I think it would be would saving $50+ on a filter.
>>
File: image.jpg (1.54 MB, 3264x2448)
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Also, this may sound really dumb, but do most cameras filter IR? Or nah.
I have a iPhone 6 I've been using for experiments that I crudely modified a while back by basically breaking the filter element off the top of the ccd to get more spectrum.
I tried looking up full spectrum cameras but it was full of garbage about ghost hunting for whatever reason.

[EXIF data available. Click here to show/hide.]
Camera-Specific Properties:
Equipment MakeApple
Camera ModeliPhone 6
Camera Software9.3.5
Sensing MethodOne-Chip Color Area
Focal Length (35mm Equiv)29 mm
Image-Specific Properties:
Image OrientationTop, Left-Hand
Horizontal Resolution72 dpi
Vertical Resolution72 dpi
Image Created2018:06:14 13:38:18
Exposure Time1/15 sec
F-Numberf/2.2
Exposure ProgramNormal Program
ISO Speed Rating400
Lens Aperturef/2.2
Brightness-0.6 EV
Exposure Bias0 EV
Metering ModePattern
FlashNo Flash, Auto
Focal Length4.15 mm
Color Space InformationsRGB
Image Width3264
Image Height2448
Exposure ModeAuto
White BalanceAuto
Scene Capture TypeStandard
>>
>>3310630
>but do most cameras filter IR?

Most cameras have an IR blocking filter installed due to the fact that image sensors are sensitive to IR light.
Some filters are stronger than others.
>>
>>3310648
Are some of them easy to remove? The iPhone one is fucking retarded hard to remove, and I'm kind of considering either trying to do a better job removing another, or just getting a dedicated camera for vis+nit
>>
>>3310665
If you have an old webcam lying around the IR filters are quite easy to remove.

Raspberry Pi do a "NOIR" camera for about $20 (just the camera, ie the board, sensor and lens only). I've been looking into them recently for projects like yours.

In the past I've disassembled things but the raspberry pi is more akin to lego, not destructive. A modular system.

As for the filter you posted, after a quick look this isn't what you want. OK it's cheap but is designed for large lenses and is not very efficient. Search about and you'll find what you want for pennies. Think surveillance, industrial and aliexpress.

Lastly, are you trying to illuminate plants with a blue laser and photograph them in IR? Just to make sure we're on the same page.
>>
>>3310718
>illuminate plants with a blue laser and photograph them in IR?
Yes.
It's called laser induced chlorophyll fluorescence.
>>
>>3310665
>Are some of them easy to remove?

Not really unless you have a Kodak or Sigma DLSR.
>>
>>3310730
>chlorophyll fluorescence.
Cool. I have no idea what that is (well I have an idea).

I wish you all the best with your endevour. Sorry I can't help any further. The other chans might help. ttfn ;)
>>
>>3310747
Sci didn't help at all, but then I realized that lasers are like 10 dollars.

Hopefully I can get a good enough set of pictures from the modified(ruined) iPhone camera to get a result. If it wow, I can get some funding from my work or at least give the info to some outside people we're working with to detect plants. It's fun stuff.
>>
>>3310851
Post your results here.

Most boards suck, /diy/ especially.
/sci/ seemed helpful the last time I was there, though.
>>
File: image.jpg (967 KB, 3264x2448)
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>>3310630
Update, I have filtered Vis light.
Same mouse bottom but with a homemade filter applied.
I just took a sharpie to some clear plastic, seems to not work for intense light though.
Still waiting for the laser to be delivered.

I'll try to get an outside pic of just ir, but the camera no longer has mechanical focus, so it's kind of locked to close range.

[EXIF data available. Click here to show/hide.]
Camera-Specific Properties:
Equipment MakeApple
Camera ModeliPhone 6
Camera Software9.3.5
Sensing MethodOne-Chip Color Area
Focal Length (35mm Equiv)29 mm
Image-Specific Properties:
Image OrientationTop, Left-Hand
Horizontal Resolution72 dpi
Vertical Resolution72 dpi
Image Created2018:06:15 13:46:24
Exposure Time1/15 sec
F-Numberf/2.2
Exposure ProgramNormal Program
ISO Speed Rating2000
Lens Aperturef/2.2
Brightness-7.7 EV
Exposure Bias0 EV
Metering ModeSpot
FlashNo Flash, Compulsory
Focal Length4.15 mm
Color Space InformationsRGB
Image Width3264
Image Height2448
Exposure ModeAuto
White BalanceAuto
Scene Capture TypeStandard




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