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 Shutter life - need help understanding machanics and myths 
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Joined: Tue Jun 30, 2009 6:14 am
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Post Shutter life - need help understanding machanics and myths
I own a Canon 5DmarkII and a Xti. I have never killed a shutter but am doing so many timelaopses I wanted to learn more about this.

Months ago I read a thread about how shooting in live view saves the shutter. I didn't reallybelieve that and quickly the thread was dropped. I feel this myth or truth has never really been confrimed. After reading on dpreivew it states this about liveview shooting:

with silent shooting disabled: "When the shutter button is pressed the shutter initially closes and the sensor is reset. The shutter then opens again, the image is taken, and the shutter closes. Finally the shutter is 're-cocked' and the camera returns to live view mode."
in mode 1: "This mode makes things quieter by using an electronic shutter for the first curtain, eliminating the initial shutter close / open steps in the sequence above.:"
in mode 2: "This is quieter still as the shutter does not 're-cock' itself until the shutter release button is released (hence continuous shooting is not available in mode 2)."

Having never tested this with an intervalometer I'm guessing mode 2 and mode 1 would be the safe as far as time lapses are concerned. But in disabled mode it appears not only is the notion shooting in liveview saves the shutter completely wrong but it sounds like it makes two actuations for every shot!! Is this correct?!

I'm trying to understand how to best save my shutter. In mode 1 (or 2) if left in liveview throughout the time lapse would the shutter therefore be electronic and never make a mechanical shutter actuation? I would love to have someone explain this to me.

Also, Recently I read somewhere (unfortunately I don't remember where) someone stated compact cameras use electronic shutters which don't require actual mechanical shutters and therefore have a much longer lifespan (in terms of actuations). Is this true? If so, for some of the less DSLR needed time lapses maybe I'll opt for a G10 or even smaller format camera (not sure when the mechanical shutter begin--I assume DSLR level).

If I'm shooting 1fps maybe it's best to use a point-and-shoot if it won't wear out the shutter on long projects.

Please help me put this to rest!!


Thu Nov 12, 2009 10:13 am
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Joined: Fri Nov 14, 2008 5:52 pm
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Post Re: Shutter life - need help understanding machanics and myths
Humm, interesting.
Thanks for notifying me of your post.
I'd be interested to read what you discover.

If your looking for a compact cam that's great for time-lapse, I use the Ricoh GX100. The 200 and Ricoh's new modular cam also have interval shooting (in RAW if you like) built in.


Thu Nov 12, 2009 11:44 pm
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Location: Aars, Denmark
Post Re: Shutter life - need help understanding machanics and myths
Here's how the shutter works depending on how you shoot:

Normal shooting without live view (shutter "rest position" is closed):
<shutter opens> <shutter closes>

Shooting in live view (shutter "rest position" is open):
<shutter closes> <shutter opens> <shutter closes> <shutter opens>

Silent shooting during live view on 5D II:
<shutter closes> <shutter opens>

As you see, during silent shooting the shutter both opens and closes once, just like during normal shooting, so you may not have gained anything. But the question is if all actuations are equal. I've marked with red color the critical operations - those that surround the actual exposure so the timing has to be accurate. For the other open/close operations, speed or accuracy isn't critical. During silent shooting with the 5D II the shutter only has one critical operation versus two for normal shooting, but if the shutter operates just the same regardless, then nothing is gained. Only a Canon engineer could tell you what's the case.

BTW, you can visually check the shutter operation during live view if you want. Take the lens off and look into the camera during shooting (exposure time of a second or so).

Most compacts (and in particular the different Canon series) have both a physical and an electronic shutter, but the electronic shutter is of a different design that can both start and end the exposure accurately (this design requires more circuitry on the sensor which reduces the light gathering area; this is why it is not used on DSLRs). So the electronic shutter performs all the critical operations while the physical shutter is just a piece of metal flapping up and down (in my cameras it's in the lens right behind the diaphragm). The purpose of the physical shutter is simply to protect the sensor from constant exposure to light when the camera isn't in use. So because the shutter on a compact is of a much less complicated design it is quite possible that it can also last much longer (just like mirrors last much longer than shutters on DSLRs - "mirror life" isn't a concern). Personally I have yet to see a failure on any of my compacts, and I'd guess my S3 is well over 200,000 photos.

Canon compacts are great for timelapse for other reasons too. With CHDK you get a built-in intervalometer (and much more), and you can use automatic modes without getting anywhere near the flicker you do with DSLRs because they adjust exposure in smaller steps (4 times smaller compared to Canon DSLRs).

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Fri Nov 13, 2009 4:49 am
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Joined: Tue Jun 30, 2009 6:14 am
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Post Re: Shutter life - need help understanding machanics and myths
Excellent information flyvholm! Thank you for sharing that with us. So in fact I'm correct that the actual number of actuations isn't less when shooting in live view (and in fact more when not using silent mode and shooting in life view). But the impact of the shutter could be different in critical releases versus operational actuations. I don't know the correct terminology or at what point the action will go from the lesser degree of wear and tear to the more damaging type. Perhaps faster releases have a more damaging effect in terms of shutter life. I could see why you would suspect a more operational release would be less damaging. Still we don't know if in fact shooting live view silent mode truthfully saves on the shutter.

Great explanation about compact cameras as well! I will definitely try using my SD880 (and doing CDHK asap) when in situations with lesser dynamic range. Where do you get the info on if your camera uses an electronic shutter for the critical releases? I would like to know for possible future purchases (i.e. would a G11?) because I plan on doing some extensive 1sec time lapse sequences and need a camera to be the workhorse (other than my DSLRs).


Sat Nov 14, 2009 11:35 am
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Post Re: Shutter life - need help understanding machanics and myths
Regarding critical versus non-critical shutter operations, my guess is actually that it makes no difference. It would be an added complication to the design, and the motivation for implementing it is probably limited. After all, when your shutter dies you'll either need a new shutter or perhaps be tempted to buy a new camera instead. Shutter failures are good business for the manufacturers.

I'm not aware of any compact cameras that use a mechanical shutter for the actual exposure. As mentioned, the mechanical shutters that can control the exposure are of a much more complicated design which is a) more expensive and b) requires more space, both of which are obvious problems for consumer compacts. The opposite is the case for DSLRs (and the hybrid micro-4/3 cameras): They all use mechanical shutters.

There's something else for you to consider though: You probably can't do 1 sec timelapse shooting with a compact - they aren't nearly as fast as DSLRs. With CHDK I can get down to just about 2 seconds between exposures on my S3 and SX100 cameras, and even though the G11 may be a little faster it is probably not much. The other thing is that CHDK only becomes available for cameras as volunteer developers manage to decipher the firmware for different models. For some models it doesn't happen at all, and for others it takes considerable time. CHDK hasn't been ported to the G11 or even the G10 yet. You can find a list of the cameras that CHDK is currently available for here:
http://chdk.wikia.com/wiki/FAQ

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Nikon D3s, D600, Canon 5D II, S3, SX100.
Feature film Beneath the Aurora on Vimeo.


Sat Nov 14, 2009 5:00 pm
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Post Re: Shutter life - need help understanding machanics and myths
thank you again, flyvholm, very informative!


Sat Nov 14, 2009 9:22 pm
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Joined: Mon Jul 21, 2014 9:57 pm
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Post Re: Shutter life - need help understanding machanics and myt
Thanks for this post!

Thought you may have some insight into my question:

Am I wrong to think that for night sky time-lapse, shooting in Silent Mode (not live view) nay be the best solution? Out in the wilderness, it gets quiet so I'm looking for a way to quiet the camera down a bit, and if there is a reduced camera shake for those pinpoint stars, even better! I guess it wouldn't save the overall number of shutter actuations, but at least I would get these other advantages, over the downsides to the other options right?

I've investigated live view, which may increase noise and will drain battery faster, as well as mirror lockup (which to my knowledge won't work with an intervelometer).

It seems the only down side to Silent Mode with the regular viewfinder is that you still flip up the mirror 700 times a night.

Any thoughts would be appreciated.


Mon Jul 21, 2014 10:05 pm
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