I have encountered unexpected behavior in the “TL/Astro (B)” and “Custom TL” modes -- modes that allow one to set exposure time. While a lapse is in progress, leaving the Running Screen seems to suspend any “end-of-exposure" commands to the camera.

Lets say I'm doing a bulb-mode lapse. If I enter the Shooting Menu during an exposure in progress, the exposure will not end after the set exposure time has elapsed. If I enter the Shooting Menu between exposures, the next expected exposure will begin on time, but then also will not end. If I return from the Shooting Menu to the Running Screen prior to the expected end of the exposure, everything continues as expected. But if I do not return -- by remaining in the Shooting Menu, by entering pause state, flashlight state, or by starting to configure a ramp (but not finalizing configuration and starting the ramp itself) -- then the shutter on the camera just stays open. When I eventually return to the Running Screen, the exposure that had stayed open will then end, and shooting resumes. Actually, “resume” may not be the right word because the shot-number counter, interval countdown, and lapse running time indicators did not suspend. they advanced properly for the time away from the Running Screen (assuming I did not go into Pause state).

I am seeing this behavior on both trigger ports of the Pro Timer 3. I discovered this behavior while on firmware 24 (or was it 23? I don’t remember what version I had before I upgraded), but it still occurs after upgrading to firmware 29. I tested on Sony A7III and Sony A7IV and with a few different cables. Also, fwiw, the behavior seems independent of what the “Release Time” setting is.

This post was last modified: 2023-10-26, 05:42 by arbiel.

Context: I came across this because I was shooting a multi-hour lapse of the annular solar eclipse on 10/14. To maintain dynamic range while composing with the sun, each “frame” was to be a bracket of 5 shots, each 2EV apart, to be merged in post. On Sony cameras, the shutter button must be depressed long enough to trigger each shot of the bracket as they are taken in rapid succession, a couple seconds in my case (10-stop ND filter to protect lens/sensor from pointing at the sun for hours). Although shorter than a typical bulb exposure, this is too long for the Release Time setting on the Pro Timer. For that reason, I used “Custom TL” mode and set exposure to 2s.

I planned to use a long interval for most of the lapse, but wanted to ramp down the interval approaching C2, then ramp it back up after C3. The specific time at which the ramps started were important to keep the final lapse symmetrical. I had alarms on my phone set for a few minutes prior to when the ramps needed to start. At the alarm, I would enter the Shooting Menu and begin configuring the ramp. I would then watch my phone clock for the right moment to commit the final step of ramp configuration, hence beginning the ramp. However, for the two periods prior to ramping I was away from the Running Screen preparing the ramp settings, I was missing shots. I did not notice this until I loaded the images into the LRTimelapse desktop app and inspected the interval column. This was a long term shoot, so my camera was on electronic shutter and its rear screen was off to save power - I did not have other cues at the time that the camera wasn’t shooting.

My camera was not in bulb-mode for the eclipse shoot, but the missed shots is what led me to further testing and understanding of this issue. it was easier to illustrate the problem using a bulb-mode example in the initial post.

Thanks for reporting this. I will have check that out and provide a fix asap.

Fixed in Firmware 30. https://lrtimelapse.com/lrtpt/firmware-updates/