topic Re: Strange light streaks with long exposure EOS 80D in EOS DSLR & Mirrorless Cameras

Strange light streaks with long exposure EOS 80D

Andydreadsbmx — Mon, 22 May 2017 01:08:06 GMT

Maybe this is a technical issue or something else but I can't figure it out.

I have noticed that when I shoot long exposures with my new 80D that some car lights give a wobbled look or a wavy pattern, is this normal? Is this just a new style of car light that is making that??

Check the below photo for a reference to what I mean, the camera is not shaking but the lights seem strange.

Let me know what you guys think or if you know let me know 🙂

Thanks!
Andy

Re: Strange light streaks with long exposure EOS 80D

TCampbell — Mon, 22 May 2017 01:21:01 GMT

The waving pattern looks sinusoidal - not digital. My guess is your camera was physically vibrating. Was your tripod set up on a bridge (or anything that could vibrate)? Was it windy and your tripod was vibrating?

Re: Strange light streaks with long exposure EOS 80D

Waddizzle — Mon, 22 May 2017 01:22:32 GMT

That is peculiar looking. Need more info to give you an intelligent explanation.

What shooting and focusing modes? What lens were you using? I assume that you were using a tripod, so did you turn off the IS in the camera because it was sitting on a tripod?

If were taking a shot like that, I would have used Av mode, One Shot mode, and turned OFF any Image Stabilization in the lens because the camera was on a tripod.

Re: Strange light streaks with long exposure EOS 80D

Andydreadsbmx — Mon, 22 May 2017 01:29:20 GMT

To reply to TCampbell It was not on a bridge or anything like that, it was on a hill side. It might have been a tiny bit windy but I don't recall it being windy enough to worry about. Also if the camera was vibrating wouldn't the rest of the shot be out of focus and not sharp?

Here is another piece of the same photo so you can see, other parts of the photo don't seem to have any issue just the traffic.

Re: Strange light streaks with long exposure EOS 80D

Andydreadsbmx — Mon, 22 May 2017 01:32:04 GMT

To relpy to Waddizzle Here is some more info on how it was shot.

ISO 100, 50mm Plastic fantastic on manual focus mode, F5.6, 2 second exposure in Manual mode on the camera.

The lens has no image stabilization and correct me if I'm wrong but there isn't any IS in the camera is there?

Re: Strange light streaks with long exposure EOS 80D

Waddizzle — Mon, 22 May 2017 01:50:11 GMT

@Andydreadsbmx wrote:
To relpy to @Waddizzle Here is some more info on how it was shot.

ISO 100, 50mm Plastic fantastic on manual focus mode, F5.6, 2 second exposure in Manual mode on the camera.

The lens has no image stabilization and correct me if I'm wrong but there isn't any IS in the camera is there?

No, there is no IS in the camera. I misspoke there. I was thinking of turning off AI Servo Mode in the camera, not IS.

Re: Strange light streaks with long exposure EOS 80D

Andydreadsbmx — Mon, 22 May 2017 01:51:45 GMT

Doesn't that seem weird though, its like the lights were moving back and forth.

Re: Strange light streaks with long exposure EOS 80D

TCampbell — Mon, 22 May 2017 01:53:19 GMT

Depending on the beefyness of the tripod, just touching the shutter button can induce some vibration (even if there's no wind or anything else).

If you have a smartphone, you can link the phone to the camera so the phone becomes the shutter trigger, or use an IR or wired shutter release, or just set the self-timer on the camera (e.g. 10 second countdown ... although the 2 second countdown may be enough to allow the vibrations to settle) and see if that makes a difference.

Canon image stabilization is always a feature of the lens - so there's no in-camera image stabilization in the 80D itself.

But some (and this was particular true of older lenses) image-stabilized lenses would get into a feedback loop if the image stabilization was turned on when the lens was used on a tripod. Newer lenses with image stabilizations are clever about detecting that they're on a tripod so they don't get into that feedback loop.

But as this was a 50mm lens (no IS feature) that wouldn't be an issue.

Re: Strange light streaks with long exposure EOS 80D

Waddizzle — Mon, 22 May 2017 01:54:25 GMT

The car lights almost look as if they were strobing ON and OFF, but I find it unlikely that every vehicle in sight of the camera has solid state LED lights. The shots are somewhat out of focus, BTW.

Re: Strange light streaks with long exposure EOS 80D

Andydreadsbmx — Mon, 22 May 2017 02:01:40 GMT

I know both of you are probably going to say "well there is your issue" but do you think it could have been because I was shooting a timelapse and the shutter opening and closing along with being on a tripod created this issue?

Here is the full shot just for reference.

Re: Strange light streaks with long exposure EOS 80D

TCampbell — Mon, 22 May 2017 02:26:29 GMT

In a long exposure the mirror swings up, the shutter opens, the camera waits the appropriate amount of time (based on how many seconds of exposure you want), the shutter closes and the mirror swings down.

It is possible to enable a mirror lock-up mode that requires a double press of the shutter to take a shot. In that mode the first time you press the shutter, the reflex mirror swings up... and that's it. The second time you press the shutter (the mirror is already up) the shutter opens and the camera takes the shot. At the end of the shot the shutter closes AND the mirror swings back down. But the point of the mode is to reduce any possible vibration caused by the mirror-slap as it swings up.

Vibrations tend to settle down (unless something is keeping them going). So on a very long exposure I'd expect to see some signs of vibration... which calm down a few seconds later and disappear.

When we do astrophotography we go to great lengths to deal with vibration issues (otherwise you get stars that are elongated instead of pin-point).

Re: Strange light streaks with long exposure EOS 80D

Waddizzle — Mon, 22 May 2017 02:26:57 GMT

@Andydreadsbmx wrote:
I know both of you are probably going to say "well there is your issue" but do you think it could have been because I was shooting a timelapse and the shutter opening and closing along with being on a tripod created this issue?

Here is the full shot just for reference.

Oh, the original shot is that big. I wonder if what you're seeing is the limit of the sensor's resolution.

Re: Strange light streaks with long exposure EOS 80D

Andydreadsbmx — Mon, 22 May 2017 02:32:03 GMT

I have used mirror lock up but in the case of the time lapse the time between frames was just long enough for the camera to process the image and start the next and I didn't think it would work correctly without having some time to do so.

Is there a way in camera to do a time-lapse and have the mirror flap up and stay open the whole time and close at the end??

Re: Strange light streaks with long exposure EOS 80D

Andydreadsbmx — Mon, 22 May 2017 02:33:14 GMT

I am seeing this now and before I was shooting with the original EOS 7D and never saw things like that.

I mean how would that happen if it is a limit to the sensor??

Re: Strange light streaks with long exposure EOS 80D

Andydreadsbmx — Mon, 22 May 2017 02:37:18 GMT

I think it does have to do with the mirror flap because in another shot pulled from the time lapse you can see the wiggle that calms down mid shot to more of a straight line.

See example of a small cropped piece of the traffic in this shot.

I guess I got confused because I feel like the shot itself would have been much more fuzzy and out of focus.

Re: Strange light streaks with long exposure EOS 80D

Waddizzle — Mon, 22 May 2017 02:42:55 GMT

@Andydreadsbmx wrote:
I know both of you are probably going to say "well there is your issue" but do you think it could have been because I was shooting a timelapse and the shutter opening and closing along with being on a tripod created this issue?

Here is the full shot just for reference.

"ISO 100, 50mm Plastic fantastic on manual focus mode, F5.6, 2 second exposure in Manual mode on the camera."

I thought you said that it was a 2 second exposure. How long of a time lapse, 2 seconds? What was the shutter interval?

Re: Strange light streaks with long exposure EOS 80D

Andydreadsbmx — Mon, 22 May 2017 02:46:59 GMT

It was a time lapse with each shot being 2 seconds with an interval of 4 seconds so it had 2 seconds to process before the next shot.

Re: Strange light streaks with long exposure EOS 80D

TCampbell — Mon, 22 May 2017 02:59:27 GMT

@Andydreadsbmx wrote:
I think it does have to do with the mirror flap because in another shot pulled from the time lapse you can see the wiggle that calms down mid shot to more of a straight line.

See example of a small cropped piece of the traffic in this shot.

I guess I got confused because I feel like the shot itself would have been much more fuzzy and out of focus.

Yeah - I think you're right. The headlight shots really do show it well in this section. We know the cars are traveling toward the camera and your an see the vibration is the worst when the shutter opens... and then calms down by the time the shutter closes.

If you are physically pressing the shutter with your finger (you touch the camera) then you can induce some vibration. Otherwise it would likely be mirror slap.

Here's a video that shows how to enable the mode: https://youtu.be/EqXI5l96Gp8

Just don't forget to disable it when you finish the time exposures or the next time you use the camera you'll be wondering why the camera doesn't take a shot when you press the shutter button.

Re: Strange light streaks with long exposure EOS 80D

Andydreadsbmx — Mon, 22 May 2017 03:05:34 GMT

The mirror lock up is great but when shooting a timelapse I cannot use mirror lock up.

Timelapse is disabled when mirror lock up is enabled. Maybe if I attach an intervalometer to the camera I could by pass that and have the mirror lock up work.

Re: Strange light streaks with long exposure EOS 80D

kvbarkley — Mon, 22 May 2017 15:10:35 GMT

Could you just be seeing a stair-step due to the square pixels? It isn't as noticable on the vertical shots.