New to the world of DSLRs and knowing that they really make taking a picture so much fun and rewarding. I am just a little confused about the rating of "Shutter Life" some manufactures boast that their flag-ship DSLR shutter has be tested to withstand 300,000 Shutters. Does this mean that when that DSLR hits 300,000 Pictures/Exposures it shuts down, just toss that 8,000 dollar baby in the trash..
Would like some knowledgeable response to understanding what they are rating??
No, no, no. When you reach the life exepectancy of your shutter, you send it in to Canon and they will replace the shutter. It's not very expensive too have the shutter replaced. DSLR's are high quality peices of equipment that are designed to be used.
For me, shutter life = reliability. Sort of. Let me explain...
Canon has rated the estimated "shutter life" of all of their dSLR's in production. This figure should give you a general idea of for how long the shutter is going to be reliable. If your body is rated to 150K, shoot away and don't be concerned about any possible shutter problems, until you reach the 125-140K mark. That's Canon raising the red flag for you. Get where I'm coming from on this? The 1-series bodies are rated to 300K - That means that the pros (or advanced enthusiasts) can shoot away to 300,000 shots without having to be concerned about shutter problems. But as you approach the rated shutter life rating, it would be wise to consider replacing the shutter in your camera.
Broken shutter, however, does not = Broken camera. Shutters can be replaced relatively inexpensively.
Hope this clears things up for you.
Originally Posted by CDiperri
When a shutter is designed, it is made of mechanical components that have to be sized for strength, durability, wear and tear, and they must be specified of particular materials, eg. high strength light weight steel for springs, pivots, etc. There are trade-offs in the design because you want to have the greatest durability possible (which can be done with big components) but since the mechanism must be made as lightest as possible (to sustain high frames per second and allow reasonably sized bodies). There's also the cost of higher quality, higher strength, and lighter weight components. The higher end bodies will have the more durable shutters built of the best materials obviously.
How mechanical components like shutters are rated for life is based on wear and tear of the components and the fatigue life of the mechanical components, like springs and pivot pins. For fatigue life, components are built to survive a certain number of cycles, statistically, before fatigue in the metal components causes something like a pivot pin or spring to break. That is the 300,000 shutter activations.
However, the most important thing to remember is the shutter life is a statistical estimate. Depending on other factors, like the quality of assembly, operator abuse of the camera (like throwing it around), average ambient humidity of operation (which may cause corrosion), and other arcane factors, the shutter life can be greatly higher or lower than what is stated. If you were a war photographer, the conditions you subject your camera to would be greater than a studio wedding photographer and there would be a higher likelihood of the shutter dying sooner. For the former, perhaps you shutter would only last half as long at 150,000 activations and the shutter for a studio photographer may last twice as long at 600,000 activations.
Camera manufacturers are probably conservative in their ratings to ensure a good reputation for their products. For anyone who is approaching the shutter life of their camera, it is something for them to be aware of. If you have been putting your camera through a hard life, you may want to bring along another body or have your shutter replaced if you have a mission critical shoot.
Check out this website to see the variations in shutter durability:
http://www.olegkikin.com/shutterlife/sitemap.php
That's a very interesting site....
One caveat with the statistics gathered is that for many models, the credibility is low due to the lack of data. It's nobody's fault, really, but it is important to keep this in mind when interpreting the charts.
Another caveat is that there is likely to be some degree of selection bias, the extent of which is unknown. That is to say, the data is not a truly random sample from the population, and it is likely that users whose shutters have failed are slightly more likely to report this data than those whose shutters have not failed. I believe that the effect of such bias is to lower the empirical survival probabilities for shorter shutter lifetimes (i.e., there will be over-estimation of prematurely failed shutters).
A third (!) caveat is that there is a right-censoring effect in the upper range of lifetimes of certain bodies' shutters because they are too new for their owners to have racked up that many shutter actuations. This data is therefore not (yet) available. For example, even if we were able to survey all the 5D Mark II owners and get an accurate count of their shutter actuations, it is unlikely that enough of them will have reached far beyond 150,000 actuations simply because the camera is still relatively new.
Of course, as more people report and the cameras continue to age, the credibility of the survival model will increase.
Finally, in a more theoretical vein, mechanical failures are generally well-modeled with distributions that are positively skewed, which means that their medians tend to be (but are not always) less than their means. Thus, MTBF (mean time between failures) is not necessarily a faithful representation of real-world performance, since it is entirely possible that more than 50% of devices fail prior to the MTBF.
I love looking at this stuff because it's right up there with my background in loss modeling. It would be great to collect more data! [8-|]
BTW, I'm not sure if anyone said this but 300,000 shots is a lot of photos.
300,000 picturesishuge load of photos even for a pro! Assuming you keep most of them.
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