madnic

Ah, yep. That makes more sense. I'll dig out an old intervalometer and try that. I realise I'm operating a bit out in the wilds with how I use the camera. It's just frustrating that this technique did work perfectly with my cheaper and more basic X-E3, but is being blocked by what's basically a programming fault in my theoretically better X-T4. At the end of this, I won't be surprised if I'm left still unable to do it on the T4. Just want to try everything I can to make sure it's not a user issue before submitting as a fault and hoping it gets patched in an update. I would try reverting to my old camera for timelapses but a waterproof housing failure left it with... issues 😆

I've had some... not success but definitely a slight improvement playing with different metering modes. Changing the ISO range had no effect. Not sure what you're suggesting with the bulb setting and external timer. That's just going to be fixed exposure length of what 1/2 second? I've got a similar timer that I've used with a Sony in the past and it doesn't allow for exposure ramping. I realise there are timers that do, but even then exposure ramping isn't exactly what you need for HG because it's not a linear transition over time.

Hi Jerryy, I'll play around with metering settings more next time I'm out there. Won't be for another couple of days til I next have a chance. It is unaffected by anything real though, and in the case of that particular sequence the spike was well away from the time of torch light that affected frames around an hour later. Presence/absence of real light sources doesn't change the behaviour. One of the places I usually set it up, the nearest light source in its field of view is a few thousand km away and it will still reliably fail. If I sit there through that period and just press the shutter button repeatedly it won't happen, so I think it's something to do with the interval timer setting. I would put it down to problems with being left unattended, but I haven't had this problem with other Fujifilms. ISO could be a good one to test. I tend to avoid going over 3200 with my 12mm lens, but anything is worth a shot.

Thanks for the welcome. Have browsed many times for questions others had already asked. Not sure what went wrong with the video embed. Have tried again below, or this links to where it's stored in my Smugmug gallery. Camera setup Fujifilm X-T4 with Samyang 12mm at F2.8 ISO Auto 800-3200 (Dynamic range 400%) Auto shutter speed (electronic) Long exposure NR OFF Photometry CENTRE-WEIGHTED IS OFF Flicker reduction OFF Interval timer shooting exposure smoothing OFF Interval set to 14 seconds, which increases to 42 seconds once exposure length ramps up to 30s. Last "correctly" exposed frame at 19:38:52, ISO 3200, Exposure 5s. The following frame at 19:39:06, 14 seconds later, has ISO 3200 and Exposure 30s. It doesn't appear to be an issue of too long an interval between shots. It's not that the light is changing too fast for the sequence, it's that the camera changes settings faster than the light. I've sat with the camera more than a few times trying to figure it out and there doesn't seem to be anything physically changing in the environment to cause it. It's just when the shutter speed should step to 5s or 6.5s, it instead steps to 30s. Problem with fixed time exposure (and yes, I can keep manually adjusting all night and it won't happen) is that I very rarely set my camera up somewhere readily accessible. It usually goes out before sunset with external battery bank setup and I hike back to wherever I'm staying the night. My most frequently captured shot is trying for holy-grail leading into an Aurora or vice versa at a lookout 30 mins jog from my accom. I'll set it up late afternoon, run back out a few hours later to make sure battery is behaving, then collect after sunset after it's been running some 10-14 hours. Obviously impractical to sit with it 😉 I've wondered whether it's a problem of using an interval setting that's less than the 30s max exposure length it ends up ramping to, which when it works just effectively slows the interval rate after sunset then speeds up again predawn. But I've tired both ways and that doesn't affect it. Did a sequence a couple of nights ago with 60 second intervals to check and it had the same problem as always.

I use my X-T4 for a lot of timelapses, and have been getting a weird glitch whenever I do a holy grail shot. I'll set it to auto exposure length, electronic shutter. At sunset it ramps nicely from 1/30000 to somewhere around 2.5~5 second exposures, then jumps to a 30-second exposure without using any setting in between. Inevitably this means about ten minutes' worth of frames are over-exposed until it gets dark enough for 30 seconds not to be terrible. After an hour or so stuck on 30 seconds, it'll start varying exposure to match actual conditions around moonlight/aurora activity, still tending towards over-exposure. Then at sunrise, same problem in reverse where it will keep the setting at 30 seconds for around 10 minutes after it should have started ramping, then jump straight to 2.5 seconds. I've updated camera firmware, tried setting lower exposure compensation, tried with "Interval Timer Shooting Exposure Smoothing" both ON and OFF. Nothing seems to work. This is my second Fujifilm I've used this way, and I never had any problem like this with my old X-E3. Attached a couple of pics showing what the transition looks like in editing. Attached video shows preview of the output when I haven't yet gone crazy with the deflicker to try to smooth it out. Sunset spike about 0:08, Sunrise at 0:45.