[amoringello]

I would test your tripod.
Paste a sheet of paper on the wall/tree with a small dot or X. (or pick a small object in the distance; light pole, street sign -- something that is basically a tiny immobile dot in your viewfinder)

Line up your viewfinder such that the X is on an exact point of the etched lines in your viewfinder.
Take a long exposure.
Look through the viewfinder and see if that remained in the same place.
FYI, taking a long exposure, as opposed to just waiting, will ensure knowing if the problem occurs or not regardless of the dot's ending location.

I wouldn't rule out anything, but sensor drifting just seems like a much less likely scenario than anything else.

[D1N0]

earthquake or you inadvertently kicked your tripod legs. Also turn sr of when shooting from a tripod. A more exotic explanation is a strong magnetic field was intermittently pulling on the sensor array.

[photoptimist]

I'm also of the opinion that the SR mechanism and not camera/head/tripod/building movement is the cause. The observed smears seem too perfect for tripod issues -- the motion is extremely smooth (hence the uniform brightness of streaks created by distant points of light) and the stop is too abrupt (the bright lights are perfect points). I'd expect tripod instability or release cable tension to induce more wiggle, slow-down, speed-up, or vibrate to a stop it it moved.

As to why the SR mechanism would command a slow pan seems a bigger mystery. If I'm interpreting the photos correctly, the pans are too fast for astrotracer (which should pan at about 1.4 pixels/second max with a 77mm lens). Composition adjust (even if one could operate it during an exposure) would probably be faster than the observed pans and also jerky (moving in 0.1 mm or 26 pixel jumps a few times per second rather than a pixel-by-pixel slow pan). Two other possibilities include:

1) one of the camera's or sensor's position sensors is mechanically or electrically loose inside the body, was sending anomalous data to the SR system, and that all the physical motion of removing the battery, frantically changing settings, etc. jostled it back into place.
2) some bit of the camera's memory got corrupted by a bug which induced strange SR behavior.

Personally, I suspect option #2 but if this recurs, then option #1 is more likely.

P.S. The "sharp" firework does not surprise me. A slow pan during a firework burst only distorts directions of the spray of lines, not the sharpness of each line (unless the firework is moving extremely slowly). The straightness of the burst lines in this case suggests a very high-velocity burst which would be especially unaffected by any sensor/camera/tripod panning.

[RAART]

If you stepped away from tripod or moved during exposure it will cause that effect. The roofs are not solid and prone to shake to slightest movement, especially if person walks or moving on them. I have done so many long exposures and only the concrete and soil or rocks are quite solid and I do not move at all... compose and make adjustments necessary and then wait for few seconds before activating the shutter. All disabled on the camera (SR, etc...)

[mikeSF]

I would test your tripod.
Paste a sheet of paper on the wall/tree with a small dot or X. (or pick a small object in the distance; light pole, street sign -- something that is basically a tiny immobile dot in your viewfinder)

Line up your viewfinder such that the X is on an exact point of the etched lines in your viewfinder.
Take a long exposure.
Look through the viewfinder and see if that remained in the same place.
FYI, taking a long exposure, as opposed to just waiting, will ensure knowing if the problem occurs or not regardless of the dot's ending location.

I wouldn't rule out anything, but sensor drifting just seems like a much less likely scenario than anything else.

the tripod has no weak points and we are talking about a smooth horizontal motion such as would be created by panning. The QR plate is tight, so is the panning knob, as is the collar to the center column, locked down. I checked all points before beginning and after first noticing the problem on playback.
thx.

[leekil]

1) one of the camera's or sensor's position sensors is mechanically or electrically loose inside the body, was sending anomalous data to the SR system, and that all the physical motion of removing the battery, frantically changing settings, etc. jostled it back into place.

The SR system was presumably on, as the OP said they turned it off along with other things, later. I don't know exactly what the results of SR while on a tripod are, but Pentax advises to turn it off in that case.

[mikeSF]

earthquake or you inadvertently kicked your tripod legs. Also turn sr of when shooting from a tripod. A more exotic explanation is a strong magnetic field was intermittently pulling on the sensor array.

earthquake? the problem occurred for about 10 minutes of shooting, so nope.

---------- Post added 07-08-2017 at 08:55 AM ----------

I'm also of the opinion that the SR mechanism and not camera/head/tripod/building movement is the cause. The observed smears seem too perfect for tripod issues -- the motion is extremely smooth (hence the uniform brightness of streaks created by distant points of light) and the stop is too abrupt (the bright lights are perfect points). I'd expect tripod instability or release cable tension to induce more wiggle, slow-down, speed-up, or vibrate to a stop it it moved.

As to why the SR mechanism would command a slow pan seems a bigger mystery. If I'm interpreting the photos correctly, the pans are too fast for astrotracer (which should pan at about 1.4 pixels/second max with a 77mm lens). Composition adjust (even if one could operate it during an exposure) would probably be faster than the observed pans and also jerky (moving in 0.1 mm or 26 pixel jumps a few times per second rather than a pixel-by-pixel slow pan). Two other possibilities include:

1) one of the camera's or sensor's position sensors is mechanically or electrically loose inside the body, was sending anomalous data to the SR system, and that all the physical motion of removing the battery, frantically changing settings, etc. jostled it back into place.
2) some bit of the camera's memory got corrupted by a bug which induced strange SR behavior.

Personally, I suspect option #2 but if this recurs, then option #1 is more likely.

P.S. The "sharp" firework does not surprise me. A slow pan during a firework burst only distorts directions of the spray of lines, not the sharpness of each line (unless the firework is moving extremely slowly). The straightness of the burst lines in this case suggests a very high-velocity burst which would be especially unaffected by any sensor/camera/tripod panning.

i think this is probably the case and perhaps the reset of the camera just cleared the issue...until next time? dunno if i should be concerned.

---------- Post added 07-08-2017 at 08:57 AM ----------

If you stepped away from tripod or moved during exposure it will cause that effect. The roofs are not solid and prone to shake to slightest movement, especially if person walks or moving on them. I have done so many long exposures and only the concrete and soil or rocks are quite solid and I do not move at all... compose and make adjustments necessary and then wait for few seconds before activating the shutter. All disabled on the camera (SR, etc...)

no. my standard technique permits no movement by me nor any proximity to other people while i'm shooting. heck, i'm so superstitious, i even hold my breath during long exposures so as to not stir up any air with my exhale. seriously, it was a very still environment.

SR was disabled.

---------- Post added 07-08-2017 at 08:59 AM ----------

thanks for everyone's input. it is appreciated.

[stevebrot]

thanks for everyone's input. it is appreciated.

Steve

[mikeSF]

and then there's this:

You Tube

You Tube

just read headline - no need to watch video.

[stevebrot]

and then there's this:

UFO Flying Over The City Of San Francisco | UFO Sightings 2017 | Alien Sighting - YouTube

just read headline - no need to watch video.

Yes! Everybody knows that UFOs cause aberrant movements!


Steve