Low Power Mode (Mach II)
Low Power Mode (LPM) allows you to do more energy efficient shooting, by powering on only part of the Mach II controller each time a photo is triggered.
It is designed to be used for short periods of fast interval shooting, where not every photo needs to be immediately uploaded.
By way of example, a scenario where you might use LPM is at a significant mid-project event like a concrete pour.
LPM will allow you to shoot at fast intervals (e.g. every 20 seconds), while connecting and uploading a photo less frequently (e.g. every 30 minutes).
This means you’re able to both shoot at fast intervals, while still getting regular photos and updates on how your system is performing.
This article is specifically about using LPM on standard Mach II units. To learn how to use LPM on Tempo, go here.
Using Low Power Mode incorrectly can result in missed photos, so it’s recommended to read through this article in full before using it.
If you’re unsure if you should use Low Power Mode, contact our Support team to discuss your project.
In order to use LPM, your system must meet the following technical requirements:
- Your photoSentinel Mach II must be fitted with a remote shutter release cable (distinct from the USB cable). This is not available on some DSLR models, including the Nikon D3400 and D3500.
- Your photoSentinel Mach II must be on at least firmware version 4.0, but ideally should be on the latest version. If your system is on an older firmware version, or to check if it is up-to-date, refer to the Firmware Update Knowledge Base article.
Limitations of LPM
The primary use of LPM is to frequently shoot and save photos to the SD card with minimal power use, to capture high-activity.
To achieve this power efficiency, LPM limits some of the other normal functionality, as follows:
- The fastest frequency at which photos can be triggered is every five seconds, but this is also limited by the camera model, exposure, and remaining SD storage capacity.
- The fastest connect and upload frequency is every five minutes. However, a less frequent regime (e.g. every thirty minutes) is recommend to maximise power efficiency.
- Photos are not immediately saved to the external drive but are transferred in bulk at the end of the photo-taking session (4.6.0 and newer). Firmware versions 4.5.3 and earlier will save the files to the external drive each time the controller powers up to connect to the cellular network during the photo-taking session.
- Photos that are not uploaded (e.g. saved locally for later manual collection) will not be deleted from the SD card, which means the SD card can fill up and the system will stop taking photos. Ways of dealing with this are explained in the “Remotely formatting the SD card” section below.
- If you are planning to use LPM for more than 1 day, the fastest recommended photo capture interval is 3 minutes. Shorter intervals will cause the camera to slow down as the SD card fills up.
- If shooting in fast-take mode, limited status information will be available, such as SD card free space, or if there is an error with the camera. Follow the steps in the “How to check status of Mach II in fast-take” section below to get status information.
Use these recommended settings for LPM:
- Uploading photos is the most power-hungry activity of the Mach II system; so, if you do not need to upload any photos during your fast shooting session, we recommend:
- Configuring the connection settings to “Don’t upload but do provide status updates” every 30 minute
- Uploading all photos at the end of the session using End of Day Uploads.
- If you do want to upload some photos during the session, we recommend not uploading any more frequently than every thirty minutes. Each time the system connects, it will upload the single latest photo, and the rest of the photos can be uploaded using End of Day Uploads.
- If you are shooting fast sessions across multiple days, then we recommend collecting the photos manually from the external drive rather than using End of Day Uploads. This will save significant power and enable you to keep shooting at fast intervals for longer.
- Where you are shooting multiple fast sessions, we also recommend using a 12V car battery with the External Battery Box to ensure you have enough power to capture all your photos.
Remotely formatting the SD card
The standard workflow for the Mach II is that it will not remove a photo from the SD card until it confirms the photo has been both transferred to the external drive and uploaded.
If it cannot confirm both have occurred, it will leave the photo on the SD card as a precautionary measure to ensure it isn’t lost. Once the SD card is full, the system will cease to take photos.
When shooting in LPM, there are two ways to collect the images:
- End of Day Uploads (under the installation’s Config tab)
- Manually from the external drive.
Where End of Day Uploads successfully uploads all photos, the SD card will be cleared at the end of each day.
Where, however, End of Day Uploads is not used, the SD card will not be automatically cleared and so will progressively fill up.
Even where End of Day Uploads is used, the SD card may also fill up before the end of the daily session if the photo files are particularly large.
The way around this is to navigate to your installation’s Status page to monitor the space remaining on the SD card, and then, when it gets close to full, set the SD card to be formatted upon next connection. The next time the system connects, it will format the SD card.*
*WARNING: In some instances, using this function may format the SD card before syncing all new photos to the external drive, and so some of the most recent photos (captured since the previous connection) may be lost.
If you plan to use LPM without End of Day Uploads, we recommend calculating how long it will take to fill up your SD card and setting a reminder to log into Control Hub and remotely format the SD card.
How to check status of Mach II in fast-take
When a Mach II is in fast-take mode, our system is not able to provide camera information such as SD card free space, or whether the camera is in fact taking pictures.
To check the status, follow these steps:
- Get approval from the relevant stakeholder to make the temporary configuration changes as the photo frequency will need to be reduced.
- Adjust the configuration to take and upload/connect every 5 minutes and disable LPM by unchecking the checkbox.
- Wait for the unit to obtain the configuration changes; wait for 1-2 status updates and image uploads.
- Verify that the camera has been taking pictures based on free space decline.
- Verify that it is currently taking pictures by checking that the uploaded image has the current timestamp.
- Once the status of the camera and unit has been verified, revert the configuration changes.