The App Is Slow with a Large Recording

Use this when

Scrubbing through a long recording feels choppy, thumbnails in the library load slowly, or the sonar view lags when you pan or zoom.

Common reasons

• Render quality set to High on a slower machine — High quality builds the sonar image at full retina resolution, which takes more time per frame on machines with less RAM or a slower CPU.
• Very long recording with thousands of pings — The app builds the visible sonar from the full ping set each time you scrub. Recordings longer than a few hours multiply the work per frame.
• Recording is on a slow drive — Reading from an old hard drive, a USB 2.0 stick, or a network share adds latency every time the app reads ping data.
• Multiple views open at once — Running the sonar view, depth chart, and side-scan together draws several canvases simultaneously.

How to check

1. Open Settings and note the Render Quality setting under Viewer Display.
2. Check where the recording folder lives — local SSD is fastest, external hard drive or USB stick is slower.
3. Watch the Activity Monitor (macOS) or Task Manager (Windows) while scrubbing to see if CPU is pegged or memory is close to the system limit.

What to try next

1. Lower Render Quality to Medium or Low in Settings > Viewer Display. The setting description reads: "Lower this if scrubbing feels sluggish or library thumbnails are slow." Snapshots you export always use full quality regardless of this setting.
2. Copy the recording folder to your local drive if it is on an external drive or network share. Local storage is significantly faster for the random reads the app makes while scrubbing.
3. Close any views you are not actively using. Hiding the depth chart or side-scan panel reduces the amount drawn per frame.
4. Use the zoom control to show a shorter time window. Zooming in reduces the number of pings drawn at once.
5. Pause playback before making large jumps in the scrubber. The app prioritizes the visible area first, then builds the surrounding cache in the background — pausing gives it time to complete that work before you move again.
6. Quit other apps that use significant memory, particularly web browsers with many tabs open.

If it still does not work

If the app is slow even at Low quality on a local SSD with a short recording, contact support at support@gethumvision.com. Include your machine model, operating system, the approximate size of the recording folder, and a description of where the lag is most noticeable.