I understand that the lens on the Pi Camera can be rotated to ensure that close up items can remain in focus. I could do to be able to use the camera to take a picture of an electric meter reading, so the camera needs to be about 25mm away.
Does anyone know if a distance this short is possible. (I don't really want to destroy the lens seals and then find that this short distance is not possible)
I have both the NOIR camera and the Daylight one and would prefer to use the NOIR version.
Thank you
Re: Pi Camera - Minimum Distance from Object
https://www.google.no/webhp?sourceid=ch ... s+distance
https://www.google.no/webhp?sourceid=ch ... hotography
Adding another lens seems to be an option also. And you would have to consider the size the item you want to take pictures of also.
https://www.google.no/webhp?sourceid=ch ... hotography
Adding another lens seems to be an option also. And you would have to consider the size the item you want to take pictures of also.
Re: Pi Camera - Minimum Distance from Object
I think you can only unscrew the lens so much before it falls out.
From memory it was 80-100mm macro close up, which is still too far away.
You might want to try one of those smart phone macro addon lens.
Some come with clips or magnets.
Or a reading glasses lens, +3+4 or higher?
One of those slide viewer magnifying lens?
I think those magnifying loupes come in 3x to 20x.
A jewelers loupe may work too, but the ones with clear plastic standoff would allow for led lighting.
From memory it was 80-100mm macro close up, which is still too far away.
You might want to try one of those smart phone macro addon lens.
Some come with clips or magnets.
Or a reading glasses lens, +3+4 or higher?
One of those slide viewer magnifying lens?
I think those magnifying loupes come in 3x to 20x.
A jewelers loupe may work too, but the ones with clear plastic standoff would allow for led lighting.
I'm dancing on Rainbows.
Raspberries are not Apples or Oranges
Raspberries are not Apples or Oranges
Re: Pi Camera - Minimum Distance from Object
@topguy & Gavinmc42
Thank you both. I have ordered a set of 3 smart phone type lenses.
Thank you both. I have ordered a set of 3 smart phone type lenses.
Re: Pi Camera - Minimum Distance from Object
Been experimenting with a remote utility meter reading application for a while, using:
Pi Zero
Pi camera V1.3
Blinkt LED module from Pimoroni
motionEysOS configured to take a still image every hour
crontab configured to run python scripts to switch on Blinkt illumination just before exposure, and off again afterwards
The attached images were taken with cameras modified by unscrewing the lens mount, after carefully releasing the three blobs of adhesive holding the lens mount. The square moulding into which the lens mount screws is very lightly attached to the camera board, and to avoid accidentally detaching it, it's advisable to hold it with pliers while unscrewing the lens.
The camera to utility meter focussing distance is approximately 110mm.
Focussing was done by trial and error.
The main difficulty is positioning the Blinkt LED module relative to the utility meter and camera to avoid reflections from the plastic window on the utility meter..
Also tried using some cheap add-on lenses for an iPhone, however when using the 0.67X wide lens paired with a macro lens this made the focussing distance far too short, with consequent difficulty in illuminating the target.
Following further optimisation of the image quality hoping to experiment with automatic number recognition, so that the 100k or so of jpg image can be reduced to a few bytes of meter reading data.
Pi Zero
Pi camera V1.3
Blinkt LED module from Pimoroni
motionEysOS configured to take a still image every hour
crontab configured to run python scripts to switch on Blinkt illumination just before exposure, and off again afterwards
The attached images were taken with cameras modified by unscrewing the lens mount, after carefully releasing the three blobs of adhesive holding the lens mount. The square moulding into which the lens mount screws is very lightly attached to the camera board, and to avoid accidentally detaching it, it's advisable to hold it with pliers while unscrewing the lens.
The camera to utility meter focussing distance is approximately 110mm.
Focussing was done by trial and error.
The main difficulty is positioning the Blinkt LED module relative to the utility meter and camera to avoid reflections from the plastic window on the utility meter..
Also tried using some cheap add-on lenses for an iPhone, however when using the 0.67X wide lens paired with a macro lens this made the focussing distance far too short, with consequent difficulty in illuminating the target.
Following further optimisation of the image quality hoping to experiment with automatic number recognition, so that the 100k or so of jpg image can be reduced to a few bytes of meter reading data.
- Attachments
-
- gas meter
- Camera1_gas_19-00-00.jpg (43.34 KiB) Viewed 3887 times
-
- electricity meter
- Camera1_elec_19-00-00.jpg (44.79 KiB) Viewed 3887 times
Re: Pi Camera - Minimum Distance from Object
@goldberg
Thank you for your reply, that is interesting.
I understand that your camera is 110mm from the meter. I really need to get a lot closer than that though and I am hoping to mount the camera on the inside of the plastic lid that hinges down at the front of the Meter box. With the position that my Meter box is mounted, the camera would get disturbed if it was too far away. The hinged lid would provide excellent protection. I picked up a pair of 3.5 reading glasses yesterday so that I can hopefully experiment with some very close up shots. I will probably use a NOIR camera with an IR ring of LED's around the lens.
Incidentally, I have very successfully, mounted a photo transistor (BPW85) in front of the LED in the Meter Box. This is linked to a Pi that counts the flashes. I just wanted the camera to take an end of day reading, although if I can successfully mount it, I may opt for more regular pictures.
Thank you for your reply, that is interesting.
I understand that your camera is 110mm from the meter. I really need to get a lot closer than that though and I am hoping to mount the camera on the inside of the plastic lid that hinges down at the front of the Meter box. With the position that my Meter box is mounted, the camera would get disturbed if it was too far away. The hinged lid would provide excellent protection. I picked up a pair of 3.5 reading glasses yesterday so that I can hopefully experiment with some very close up shots. I will probably use a NOIR camera with an IR ring of LED's around the lens.
Incidentally, I have very successfully, mounted a photo transistor (BPW85) in front of the LED in the Meter Box. This is linked to a Pi that counts the flashes. I just wanted the camera to take an end of day reading, although if I can successfully mount it, I may opt for more regular pictures.