Canon R7 Movie Time lapse setting

[EVaughan]

When using the R7 time lapse movie mode, if you use a shutter speed of two seconds or longer with two second interval chosen. Will the camera skip frames because it's trying to take an image every two seconds, but the shutter could be open exposing one image for two seconds or longer. Or will if just use 2 second interval between each image no matter how long of shutter speed you have chosen? 

[Waddizzle]

The camera will faithfully fire the shutter at whatever interval you set.  It is completely independent of shutter speed.  It is up to you select an appropriate interval and shutter speed.

[EVaughan]

So you are saying that in Timelapse movie mode, if I set a 2 second interval and set a shutter speed of say 4 seconds. Then each shot will be four second long exposure, then wait 2 seconds and take the next shot without skipping frames? Reason I question that is because when you're setting up the camera to take Movie mode Timelapse you set the number frames you want taken, then interval between each frame. Then the camera shows how long it will take to take that many frames with the interval you selected and how long of movie clip it will create from those settings. So how can the camera know how long it will take to take that many frames if it doesn't take into consideration the shutter exposure time? 

[Waddizzle]

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@EVaughan wrote:

So you are saying that in Timelapse movie mode, if I set a 2 second interval and set a shutter speed of say 4 seconds. Then each shot will be four second long exposure, then wait 2 seconds and take the next shot without skipping frames? Reason I question that is because when you're setting up the camera to take Movie mode Timelapse you set the number frames you want taken, then interval between each frame. Then the camera shows how long it will take to take that many frames with the interval you selected and how long of movie clip it will create from those settings. So how can the camera know how long it will take to take that many frames if it doesn't take into consideration the shutter exposure time? 

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I did not say that, at all.  Let me repeat.  The camera will try to fire the shutter at whatever interval you set.  If you want to fire the shutter every two seconds, then your exposure needs to be completed  well under two seconds..

[paulhummerman]

"well under"? I shoot Milky Way timelapses with 8 sec exposures. Usually I set the interval at 10 secs, to allow each exposure to be completed. But can I set the interval at 9 secs with enough time for all exposures to be completed? Or even an 8 second interval? The manual is silent.

[Waddizzle]

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@paulhummerman wrote:

"well under"? I shoot Milky Way timelapses with 8 sec exposures. Usually I set the interval at 10 secs, to allow each exposure to be completed. But can I set the interval at 9 secs with enough time for all exposures to be completed? Or even an 8 second interval? The manual is silent.

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Please note that I keep referring to the “exposure time”, not the shutter speed.  This is because some of the Noise Reduction in the camera may extend the length of time it take to complete an exposure to up twice the shutter speed, or even longer as it writes data to the memory card.

For example, between High ISO NR and Long Shutter NR, one of the other will take the time to capture a second exposure using the original shutter speed to use as a reference for the NR algorithms.

This means your 8-second exposure can easily take over 16-seconds to actually complete!  

I have run into this trying capture multiple images of the Moon in quick succession.  If I get the timing incorrect, the camera will capture the first frame in the sequence, and then abort the entire cycle.

[paulhummerman]

Thanks, helpful. I had not realized that NR lengthens the exposure time relative to the shutter time. On all 3 of my RP cameras I see that it was set to Standard. There doesn't seem to be an option to turn it off completely. Does the amount of extra "exposure" time is adds depends on the setting? Should I set it to "low" rather than "standard" to minimize this exposure lengthening issue?

[Waddizzle]

If you are experiencing issues with interval shooting, then I strongly recommend that you begin your own thread for your issue.

This thread was created by someone having issues with capturing frames for time-lapse movies, which is a completely different shooting scenario from your issue with capturing full resolution images using the built-in intervalometer.  .

[paulhummerman]

My issue was exactly the issue that EVaughan raised initially - how does the "exposure time" interact with the "interval time" when shooting time-lapses? You are saying I think that in order not to lose information one must set the interval to be longer than the "exposure time" not just longer than the "shutter time" - although there is apparently no way to know how much longer. I mostly shoot Milky Way time-lapses and use a 8 sec shutter time and a 10 sec interval, and that seems to work fine. I guess that the extra 2 seconds is enough to write the data to disk and perform the "standard" High Iso NR. When I use an interval equal to the shutter time the time-lapses still work but oddly enough the actual interval between shots seems to be prolonged or unpredictable.

[BrianDavies]

It is fairly simple. The interval between shots MUST be longer than the shutter speed. The shutter speed is the exposure time (shutter speed = how long the shutter is open and exposing the sensor to light).

So you have 2 choices,
1. to set an interval for the time between one shot commences and the next shot commences or;
2. the time between one shot ends and the next shot commences

The solution to 1. is set an interval = desired interval, but interval 'must' be longer than shutter speed. Obviously, a new exposure cannot begin when another exposure is still in progress.

The solution to 2. is set an interval = desired interval + shutter speed.