In shooting time lapses of satellites using the continuous shooting setting on my A7RII, I see a gap between satellite trails in subsequent frames. I've tried shooting at 1 sec, 1/2 sec, and 1/4 sec and all have a gap in the trails. I'm using a 24mm G-Master lens wide open at f1.4.

This camera has to use the mechanical shutter when using continuous shooting so it's also racking up a LOT of wear for long time lapses.

My suspicion is that this camera has:
1. Too slow of reading the chip for each frame into the buffer for gapless continuous shooting.
2. Perhaps other things the camera is doing before it takes the picture (autofocus even though the camera/lens is set to manual focus).
3. Too slow of a write to the buffer and subsequently the SD card.
4. Mechanical shutter needs time to recover.
5. The buffer might not be able to keep up with writing to the SD Extreme Pro card. But this gap also occurs initially too, without the buffer being full.

Would love to know how best to prevent these gaps in these trails as it produces very jerky time lapses when played back.

Thanks!
Rick

I've designed the LRT PRO Timer with the goal to achieve the shortest dark times possible, much shorter than with the internal intervalometers that most cameras offer and also shorter than most external intervalometers. In the manual you will find instructions on how to fine tune the PRO Timer to allow the shortest dark times possible with your specific camera. https://lrtimelapse.com/lrtpt/manual
But still, depending on the camera, you will have around 0.3 seconds minimum dark time. Depending on the exposure time and focal length this might be short enough to prevent such gaps. Additionally I'd recommend rendering in LRTimelapse with a certain amount of motion blur, this helps tremendously with such sequences.
Of course, you should use a decently fast memory card which doesn't slow down your camera.

This post was last modified: 2024-01-23, 04:25 by starman99.

Hi Gunther, Thanks for the reply. I'm not using an intervalometer. Instead I'm using continuous shooting mode. I'm considering your timer, but I'm not convinced my camera can respond quickly enough because of the read time for the chip, slow transfer speed (USB 2) to the SD card, etc.

I'm thinking about giving up on the a7RII and moving to a Nikon Z6II instead.
Thoughts?

Sorry, I didn't see that you were shooting continuously. I don't know about the performance of your Sony, that's why I can't tell you definitely how it would perform with the LRT PRO Timer.
I can tell you however, that the Nikon Z 6II is great for timelapse. I use it very often. It performs very well, just make sure to use a cfExpress card for the best performance. The only think you should know is that the Z6II and Z 7II don't let you shoot more than 100 or 200 images in continuous mode. So this strategy that works on other cameras like Sony (but also the Z 8 and Z 9) doesn't work with the smaller Nikons - you would need to use an external intervalometer.

Thanks Gunther. Yes, I plan to use the cfExpress card, one of the reasons I want to change cameras for sure. In continuous mode on your Z6II, is there any dark time if the camera is on manual focus? How long is Nikon's dark time on the Z6II's internal intervalometer? Thanks again, Rick

Every camera has a dark time, also in continuous mode. Currently I don't have a Z 6II here, therefore I can't tell you, how long it is. It might also vary during shooting depending on the exposure time, as the buffer fills up. Personally, I don't use that technique and as I said on the smaller Nikons like the Z 6II there is a limit to 100 or 200 images in continuous shooting anyway.
I also can't tell you the dark time on the internal intervalometer, since I don't use it because it leaves the camera unresponsive and I get no image previews etc while shooting.

Got it. Thanks. Which camera are you currently using for your time lapses?

Mostly the Z 8. It's a beast, works great for everything!

Yes, seems that way. What do you do about those big RAW file sizes with the Z8? Won't they add up quickly and slow down the time-lapse constructions for long time-lapses? Or do you save them compressed?

I don't do long term...