Inherent flaw with mirrorless cameras?

[Finelld]

I am a retired broadcast studio engineer and have maintained many electronic cameras over my career all the way back to vidicon tubes.  I have a big concern with the mirrorless design because when the camera is in use the sensor is exposed and even when it isn’t the shutter is absorbing all of the light energy from the lens.  Lenses are basically just complex magnifying glasses.  Have you ever seen what the sun will do to leaves or paper through a magnifying glass?  Many of the sensors I have worked with over the years were sensitive to high intensity light and could be permanently damaged by it.  Especially the vidicon tubes but CCDs and others to lesser extents.  I am concerned about sensor damage and to a lesser extent shutter damage on mirrorless cameras when framing a scene with the sun or other high intensity light sources like lasers.  I have heard of several instances of sensors of mirrorless cameras being damaged after shooting concerts or nightclubs with laser shows.

DSLRs don’t have this issue unless you are shooting video or live view.  They direct the light around the shutter and sensor and out the eyepiece.  As such very little energy from the light is absorbed by any internal camera components.  The sensor and shutter would only be exposed during the fraction of a second the mirror is swung out of the way.

I have a tremendous amount invested in my EF lenses and DSLR bodies and don’t intend to change anytime soon.  But with Canon discontinuing DSLRs and the EF line these will no longer be supported and I will need to change unless Canon reconsiders its decision.  As shooting backlit images with the sun in the frame and concert photography aren’t uncommon I want to know how mirrorless manufacturers address these concerns and what other photographers experiences are.  Manufacturers like mirrorless because they are less complex and cheaper to make.  But how will that affect consumers if they need to routinely replace the sensor which is arguably the most expensive camera component. 

[Waddizzle]

I would be just as concerned, if not more, about sunlight damaging the lens than the image sensor in the camera.  I not aware of any image capturing device that can be pointed at direct sunlight and not be damaged without some type of light filtering.  Do you?

[TomRamsey]

I have been taking sunrise and sunset photos for years with DSLRs using liveview and have not had any problems.  Now I would not take pictures of the sun directly when it is higher up, that’s just not good sense.  I think it was a real concern in normal photography we would have heard a lot more about it, since mirrorless cameras have been around for quite awhile now.

[Tronhard]

Let's unpack this a bit... I think we have two issues here:
1. Potential technical issue with not having a mirror mechanism in MILCs and thus damaging the sensor. 
To quote the OP:  "I am concerned about sensor damage and to a lesser extent shutter damage on mirrorless cameras when framing a scene with the sun or other high intensity light sources like lasers."   
One of the things one learns early on in life is not to stare at the sun directly, certainly not through a magnifying glass or a telescope - it can blind you. Even reflected light off snow can cause snow blindness, something the ancient Innuit bands of the far north combatted with snow goggles, just as we use sunglasses for today.  So, looking at a bright light without optical focusing is, in itself, a high-risk endeavour - common sense applies.  If one is shooting a solar eclipse there are lots of advisories on how to do so to  protect cameras and our eyesight: e.g. this warning from NASA "

#1 – Safety First

Looking directly at the Sun is dangerous to your eyes and your camera. To take images when the Sun is partially eclipsed, you’ll need to use a special solar filter to protect your camera, just as you’ll need a pair of solar viewing glasses (also called eclipse glasses) to protect your eyes." 
Ref: Five Tips from NASA for Photographing a Total Solar Eclipse - NASA 

Such warnings have not been limited to MILCs, or even DSLRs - they have been relevant for as long as photographers have had the ability to photograph the sun.  However, cameras are not simply just magnifying glasses.  They have a wide range of focal lengths that can reduce the size of the sun to a tiny fraction and intensity of what we can see with the naked eye, and they have usually multiple layers of coatings to reduce glare.  Finally, they have an aperture to cut down the total amount of light reaching the viewing mechanism or sensor.  MILCs have the ability to automatically close the aperture to reduce light intensity, and many actually have a mechanical shutter to further protect the sensor.

As far as lasers are concerned there have been numerous instances of people shining lasers at aircraft where the pilots have been temporarily blinded by the intensity of the light, and that is without magnification - there are legal measures and penalties against doing so. For laser lights at a show, that is something the performers need to control under health and safety legislation for each country, and anyone photographing them would be wise to avoid looking into them as previously explained.  Again it's not so much a case of the viewing device as the common-sense measures of protection and accident prevention.  In line with other countries, NZ has brought in legal measures to control high-powered lasers, including importing for shows to quote from the legislation:
"In brief, these laws state that: 

• you need consent from the Ministry of Health in order to import a high-power laser pointer
• you need authorization from the Ministry of Health in order to supply (sell or give away) a high-power laser pointer
• you need authorization from the Ministry of Health in order to acquire (buy or receive at no cost) a high-power laser pointer."  Questions and answers: New controls on high-power laser pointers | Ministry of Health NZ

Lasers | Civil Aviation Authority (caa.co.uk)  
Sony Officially Warns That Lasers Can Damage its Cameras' Sensors | PetaPixel
Do Bright Lights Damage Camera Sensors? - Your Photo Advisor

I could go on but I hope I made my point...

With DSLR's the risk is far more personal, as the mirror is reflecting the intensity of light straight up to the viewer's eye with the aperture fully open for focusing. That could cause serious eye damage if one was using a telephoto lens and shooting at any intense light source like the sun.

Opinion as Requested:
I have been shooting with both SLRs, DSLRs and Mirrorless for quite some time. In the former, since about 1980 and in the latter category I would include point and shoot MILCs from over 10 years ago and the M-series cameras that behave just like their R-series descendants.   I have never been unwise enough to point my camera at an extremely bright light source without careful risk analysis and mitigation.  However, I would actually prefer to have to take the risk with a MILC, as the sensor is bearing the brunt of the light energy and not my eye directly, as it would through the reflected light of the mirror.  I would much rather burn out a sensor than my eyesight. 

Finally, one has to ask how often we will find ourselves in that situation where we are engaged in such an activity.  I would hazard that it is not often unless one specialized in such efforts, in which case that would come with some education and an abundance of prudence.

So, in summary, the issue is not specific to MILCs, it's not even specific to cameras or binoculars or telescopes.  It's about assessing risk and applying common sense.

2. A personal preference for DSLRs over MILCs:
That is a purely personal choice which one is absolutely at liberty to have and apply - no argument there!  It is unwise to try to underpin that personal preference by dubious amplification of risks as above.  The argument does not hold water (or bright light).

That said, Canon is not alone in moving from DSLRs to MILCs - every major brand is doing precisely the same.  So, I would encourage our OP to buy the DSLRs he prefers from wherever, while they are still on the market if he wants a new one.  That said, I would still caution him to not point them at bright lights.

List of References:
Can the Sun Damage Camera Sensor? (And How to Protect It) (digitalworldbeauty.com)
Questions and answers: New controls on high-power laser pointers | Ministry of Health NZ

[ctitanic]

First of all, you need to use common sense. Here is what I found looking around the web:

"A commercial laser used in a concert can potentially damage a mirrorless camera sensor. Concert lasers are often powerful and, if they strike a camera's sensor directly, they can cause significant damage. The intensity of the laser can burn or permanently damage the pixels on the sensor, leading to dead or stuck pixels, discoloration, or other forms of sensor malfunction.

The risk is higher for mirrorless cameras, where the sensor is more directly exposed during shooting (especially in live view or video mode) compared to DSLR cameras, which have a mirror mechanism that might offer some protection when not actively capturing an image.

To avoid this risk, it's important to be cautious when filming or photographing in environments with laser light shows."