stereo camera for long exposure time

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julsboo
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stereo camera for long exposure time

Post by julsboo »

Hi
I have all the necessary elements and I've just started to look at the software part in particular with SLP.
I bought 2 HQ Cam because I want to adjust the focus and aperture on the lenses.
My main goal is to use the stereo camera for light painting
I'm encountering two difficulties.
  • it seems to me that the shutter speed is not adjustable from SLP, yet the HQ Cam with Raspian allows 200 seconds of exposure time.
  • feeds from both cameras is blurry and I can't focus manually. is there any adjustments to be made for the HQ Cam? Or is this camera natively supported? In which case I might have a problem with my 2 lenses!

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julsboo
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Re: stereo camera for long exposure time

Post by julsboo »

I solved the focus problem, I just hadn't removed the back focus ring from the camera module which is necessary with the 6mm lens.
So the feeds from both camera is OK by now :geek:

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julsboo
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Re: stereo camera for long exposure time

Post by julsboo »

Concerning the shutter speed I modified the make_photo.php file as explained in the excellent article "THE ART OF STEREOSCOPIC PHOTO, PART 2".
so I managed to increase the exposure time.
How can I add a number field that allows me to quickly adjust the exposure time in the settings?

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Realizator
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Re: stereo camera for long exposure time

Post by Realizator »

Hello Julsboo,
As you noticed, our SLP code is a mix of admin panel (PHP) as a frontend, and bash for a backend.
If you wish to add a new parameter to the admin panel, you can:
1. Edit /var/www/html/index.php and add an intrface element, for example "Exposure time", with appropriate id (like id="my_exposure_time")
2. If you want your settings to be saved using "save" button, look at this function "$('#save_button').on('click', function() {" and add your parameter here.
3. You can use your number under id="my_exposure_time" as a parameter for the image capture command, instead of hardcoding it.
Eugene a.k.a. Realizator

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Realizator
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Re: stereo camera for long exposure time

Post by Realizator »

Julsboo, I'm curious, what lenses are you using with the HQ camera? I'm using 16mm lenses (suggested by Raspberry), but I feel problems with its "focus depth". I can focus either on nearby objects or on far objects, regardless of the iris settings.
Eugene a.k.a. Realizator

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julsboo
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Re: stereo camera for long exposure time

Post by julsboo »

Thanks for your answer Eugene I'll look into it.

I bought the 6mm lenses suggested by Raspberry
Did you check instructions here https://static.raspberrypi.org/files/pr ... _Guide.pdf

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Re: stereo camera for long exposure time

Post by Realizator »

Julsboo, 6mm lenses are more friendly to the customer. Actually we've tested a lot of lenses, and in a process of developing a special metal housing for the stereoscopic setup for HQ cameras. :-)
Eugene a.k.a. Realizator

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julsboo
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Re: stereo camera for long exposure time

Post by julsboo »

I saw your metal housing, looks sturdy!

Honestly I'm afraid of having problems with aperture and focus with the 6mm lens. The two lenses don't seem to be calibrated in the same way, the back focus is set differently from one lens to the other. I'll deal with that to start with.

Concerning the housing I would like to make a 3D print with 1 module that would contain the stereopi and a camera and then another mobile module with the second camera. In order to adjust the stereobase

I've never done 3-D printing, so I still have a lot of work to do...

If you ever have any suggestions, I'm up for it ;)

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