This post was last modified: 2022-02-13, 23:57 by mcrtchly.

Gunther

I've just brought a LR Timer Pro 3 - a great addition to my kit. But I have noticed some variability of the intervals between shots (but no dropped frames). I tried two tests; firstly controlling day to night Holy Grail with qDslrDashboard with LR Timer on a Sony A7S and then a home just using LT Timer (without qDslrDashboard). My settings on the camera where

All auto corrections off
Manual exposure
Manual focus
Silent (electronic shutter)
fixed aperture (manual lens - no electric coupling)
8sec shutter speed (for non qDslrDashboard test) otherwise 1/60 to 8sec max for qDslrDashboard Holy Grail test

LR Timer Pro settings

Firmware 27
Manual timelapse
10 second interval
360 frames
Release time 330ms (increased from default to allow for electronic shutter)
autofocus time 100ms
DLSM standby 15sec

As can be seen in the attached PDF the interval between frames can vary. The snapshots 1 and 2 from LRtimelapse shows the intervals for the qDslrDashboard timelapse whilst the 3rd snapshot is for the non-qDslrDashboard test. Note that in snapshot 1 that there's variable interval even with a short shutter speed (long dark interval). But that there's variability in snapshot 3 suggests that qDslrDashboard isn't the problem.

Again, I stress that there where no dropped frames. So should I be worried about variable interval between frames or could these be apparent differences in interval due to the camera recording time to the nearest second rather than using milliseconds?

Regards, Martin

That camera seems to write timestamp values rounded to seconds into exif (with other cameras, that write fractions of secons, LRTimelapse would show 9.9, 10.1 etc. as intervals). That means with your camera, 9.9 secs will be displayed as 9 then the next interval will be 11 obviously because the intervals are being calculated as difference of timestamps. As long as the deviation is displayed as 1 sec on a camera that doesn't write fractions of seconds, this is totally normal and won't mean that the interval is not constant. That's why LRTimelapse doesn't show those intervals in "red". Only interval deviations >=2 secs will be displayed in red and would mean something is wrong.
I can assure you that the LRT PRO Timer triggers fairly constantly and accurately.
However the internal intervalometer of qDDB is known for being not as accurate. Therefore I'd always recommend using the LRT PRO Timer for triggering the camera.

Thanks for your prompt reply, I had guessed that you are correct about the camera reporting times rounded to the nearest second. But in the case of the qDDB sequence I used the intervalometer on lrt timer not qDDB; should I perhaps be cautious and aim for a 3sec dark gap between exposures using LR Timer? For daylight timelapse on my Pentax K1 using its internal timelapse I usually aim for 1.5+sec gap. Anyhow so long as it's not dropping frames then I'm happy. Will be testing anger during an astro photography tour with clients in the Canary Islands in May.

Martin

If it's not dropping frames, you usually don't need to increase the dark time.