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To determine the effect of the stable color temperature, it makes sense to run a stress test with and without it at our desired flash power. That would also help answer whether the flash will bottleneck the bbot at the given power level (edited)
Protocols
Camera
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Testing Protocols: Bbot Version 3.1
Setup
Camera Placement:
Position the camera lens
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170 cm (+/- 5 cm) above the pot surface
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.
Allow the camera to move up (along the z-axis) as plants grow taller.
ColorChecker Placement:
Place the primary ColorChecker card 15 cm above the pot surface
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.
Use a secondary smaller ColorChecker card at pot level for focus confirmation.
Initial Camera Configuration
Aperture:
Set the aperture to the lowest number (f/4)
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adjust exposure
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start finding the right focus so that the milliliter scale on the colorchecker are incredibly clear, adjust by millimeter. For example here is how the scale bar should look - 
.png?version=2&modificationDate=1731945761250&cacheVersion=1&api=v2)
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after the right focus has been identified, set it using the set screw
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now adjust aperture and exposure as needed
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Set max camera height ~1.7 meters above pot top ->
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set focus according to the color checker at aperture=F4 ->
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Increase flash power + increase F-number to around 10.
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Set exposure time to 250 uS.
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Modify aperture up or down until an appropriate exposure level is reached.
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for initial focus adjustments.
Focus Adjustment:
Adjust focus carefully until the millimeter scale on the ColorChecker card is extremely sharp. Adjust in millimeter increments for precision.
Once the ideal focus is achieved, secure the setting using the set screw.
Exposure and Flash:
Gradually adjust the exposure and flash power to achieve proper lighting.
Suggested settings:
Exposure time: Start at 250 μs. Adjust as needed.
Flash power: Increase as aperture values rise.
Refining Settings
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Aperture and Exposure:
Increase the aperture to f/10, then modify it up or down as needed for proper exposure.
If images appear too bright, increase the aperture to f/11 or f/12.
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as f number increase, image quality generally increases but as it get too high image quality decreases
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The camera should stay at 170 +- 5 cm
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only moving up as plant grow taller
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generally don’t want images to be too bright because you risk over exposure with flowers or wet pots
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only thing that changes would be the height of the camera (z-axis) in the upward 20cm direction. The camera should only move up with the increase height of plants
Note: Higher f-numbers generally improve image quality up to a point but can degrade quality at extremely high values.
Depth of Field:
Aim for an aperture near f/12 or f/13 for optimal depth of field, which increases by approximately 25% at these values.
Strobe Delay:
Test strobe delays at 50, 100, 150, and 200
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μs, keeping the exposure time
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constant at
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100
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μs.
If the image is too dark:
Lower strobe delay to 25 μs or 0 μs.
Adjust exposure back to 250
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use a second color checker card at pot level to confirm that images are in focus with above adjustments
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what if the small color checker is not in focus?
increase the f-number to 13 and the flash power to full power
if images are too underexposed, can increase
increasing exposure
Maybe we need to increase the F-number then, and increase the exposure time slightly. As well as the flash power
getting f number closer to 12/13 is more ideal
depth of field will likely increase ~25%
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if the small color checker chart is still out of focus, we can adjust the gain
Color correction
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μs if necessary.
Troubleshooting Focus
Secondary ColorChecker (Pot Level) Out of Focus:
Increase the aperture to f/13.
Set the flash to full power.
Underexposure:
Increase exposure time, flash power, or both.
Consider raising the f-number slightly (closer to f/12 or f/13) while adjusting exposure and flash settings.
Focus Challenges:
If the small ColorChecker remains out of focus, adjust the gain incrementally until clarity is achieved.
Key Considerations
Maintain Height Consistency: Keep the camera at 170 cm above the pot top unless plant growth necessitates adjustments.
Avoid Overexposure: Be cautious with flowers and wet pots, which are prone to overexposure.
Lighting and Exposure: Proper balance between aperture, flash, and exposure time is critical to avoid overly bright or dim images.
Color Correction
Protocol for One-Time Configuration
This protocol outlines the steps for the one-time configuration required to process images collected with the Bbot V3.1 system. This configuration process involves generating a .pp3 configuration file that will be used for future batch processing.
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Step 1: Image Collection
Collect images using the Bbot V3.1 system.
Make sure camera, flash, and bbot settings are correct
Ensure metadata is recorded with each image, including:
Exposure time
Aperture
Location
Date and time
Thumbnail
Camera height (z-axis)
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Step 2: Convert RAW to DNG
Convert the RAW files from the image collection to DNG format using a suitable tool (e.g., piDNG or similar).
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Step 3: Demosaicking
Perform demosaicking on the RAW images if required, to prepare them for color correction.
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Step 4: Calculate Color Correction Matrix
Using a representative subset of the images:
find the corresponding RGB values in RawTherapee using the color picker and “change foreground”
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tools
Calculate a color correction matrix to ensure accurate color representation during processing.
Make sure the image is not overexposed (verify using the RawTherapee histogram)
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Step 5: Adjust Image Parameters in RawTherapee
Import the DNG files into RawTherapee.
Perform the following manual adjustments:
Exposure compensation: Adjust exposure levels for uniform brightness.
Lens correction: Correct lens distortion.
White balancing: Adjust white balance to ensure accurate colors.
Gamma correction: Modify the tone curve to optimize brightness and contrast.
Sharpening: Enhance image details.
Verify the adjusted settings by visually inspecting the images.
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Step 6: Save Configuration File
Save the adjustments made in RawTherapee as a
.pp3configuration file.Ensure this file captures all the applied adjustments.
Name the file appropriately to reflect its purpose (e.g.,
default_processing.pp3).
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Step 7: Validation
Test the
.pp3configuration file on a few images to ensure consistent and accurate processing.Make further adjustments to the configuration file if necessary.
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Step 8: Finalize the Configuration
Once validated, store the
.pp3file in a secure and accessible location for use in the automated batch processing pipeline.
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Manual Gamma correction:
not recommended, useful if we want to quickly process images to test autosfm
https://stackoverflow.com/questions/71734861/opencv-python-lut-for-16bit-image (quick and easy gamma correction, not ideal for longterm workflows)
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