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Changing lenses


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Hi

 

I have been a Sony user for nearly 5 years now and I note that I am tending, as others as well, to use just prime lenses.

During a recent short trip to Wales the weather was bad but I still took some photos and of course changed lenses. On getting back to the hotel the sensor was no longer clean and I had to find a shop which would sell me a sensor cleaning kit - so far so good.

But then I asked myself why?

On mirrorless cameras there is a shutter which goes across the sensor! Why cannot I close this before changing lenses? A control in the menu is (IMHO) all that would be required. The possibility to assign this to a button on the camera would also be nice to have. With a closed shutter the sensor would stay clean.

Or am I missing something and this can actually be programmed?

This is not practical on the Sony A-mount as here the shutter is behind the mirror and the mirror is fixed.

Surely this is a simple thing that could be done in software and would mean that one would only have to clean the sensor only very occasionally - instead of after each trip when the weather is bad (OK you can be very very careful but with damp and windy weather there is still a chance that the sensor will be soiled)

 

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Hmmm, if the dust falls on the shutter, and then you put on the lens, where does the dust on the shutter go next ... thats how it goes with prime lenses.

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Hmmm, if the dust falls on the shutter, and then you put on the lens, where does the dust on the shutter go next ... thats how it goes with prime lenses.

Dust is going to fall into the camera, not land on the sensor but end up inside the camera anyway. If dust was to fall on the closed shutter it would probably also end up in the camera when the shutter closed. So probably you would end up with just a bit more dust inside the camera but as I said one would need to clean the sensor - and the inside of the camera - occasionally anyway.

Often I find the sensor has a tiny drop on it which causes a mark on the sensor - if this fell on a closed shutter it - probably - would have no effect.

"thats how it goes with prime lenses." sounds very defeatist, if my suggestion would improve things then it should be done. I never said it would solve all the problems when changing lenses!

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if my suggestion would improve things then it should be done. I never said it would solve all the problems when changing lenses!

 

It does seem obvious, and there's doubt that Sony hasn't thought of it too.  If they haven't implemented it, it's probably because not only will it not improve things, but it might actually make things worse.

 

Think about it: the sensor has a glass surface, any dirt that gets onto it, you just wipe off and that's the end of the story.

On the other hand, the shutter is a complex mechanical component with several interacting moving parts.  Any dust or dirt that gets in there is much more difficult to remove.  And if it stays there, then it could gradually increase the wear'n'tear.  Which reduces the lifespan of the the shutter, which was already limited in the first place.  And once there's enough build up of this dust and dirt, it will eventually work its way through to the sensor anyway.  So not only will it cause other problems, but it won't even solve the problem its meant to solve, it would only delay it.

 

With all that in mind, it's more preferable to simply have to clean the sensor from time to time.

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It does seem obvious, and there's doubt that Sony hasn't thought of it too.  If they haven't implemented it, it's probably because not only will it not improve things, but it might actually make things worse.

 

Think about it: the sensor has a glass surface, any dirt that gets onto it, you just wipe off and that's the end of the story.

On the other hand, the shutter is a complex mechanical component with several interacting moving parts.  Any dust or dirt that gets in there is much more difficult to remove.  And if it stays there, then it could gradually increase the wear'n'tear.  Which reduces the lifespan of the the shutter, which was already limited in the first place.  And once there's enough build up of this dust and dirt, it will eventually work its way through to the sensor anyway.  So not only will it cause other problems, but it won't even solve the problem its meant to solve, it would only delay it.

 

With all that in mind, it's more preferable to simply have to clean the sensor from time to time.

 

Not quite logic: all DSLR would suffer from the same problem, as the mirror offers just partial protection to the curtain/sensor dust/spray capturing. And they promise as long shutter lives as any mirrorless. Shutter wear is not the issue and it would be stupid to preffer sensor smearing to preserve your shutter, as image quality is the first goal of the camera manufacturers.

On the other hand, it is curious that I needed to clean my sensors more often when I used DSLR's while I keep the same lens changing method. I suspect that the mirror acts like a fan, blowing the dust sitting inside the camera at every exposure.

While my opinion may not be the last word, I agree that if dust gets inside the body it may move to the sensor later, shutter open or closed. But with it open you exponentially increase the odds that it happens while changing the lens.

As the SLR's have the provision for a cleaning mode, when the mirror is raised and the shutter opens, it would surely be an easy and wise measure to do provide the opposite for the mirrorless cameras: an option to close the shutter for lens changing. So I agree with Kestrels. And I said an OPTION​, as suggested in the original post, you may use it just if you wish.

While we wait for the engineers to understand this simple question, I keep my strict measure not to open a camera body in dangerous (for the sensor) environments. Also prefering primes, I try to carry as many bodies as the lenses that I may need (eventually a zoom to cover the less probable focal lenghts). So each body may be specifically set for the lens it is carrying.

And I do change lenses only in clean an DRY environment.

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On the other hand, it is curious that I needed to clean my sensors more often when I used DSLR's while I keep the same lens changing method. I suspect that the mirror acts like a fan, blowing the dust sitting inside the camera at every exposure.

 

That is curious.  Even moreso when you realize that DSLR's keep the shutter closed all the time, except for the fraction of a second during an exposure.  (Edit: or an extended period of time during live-view)

This implies that closing the shutter is simply not an effective way of keeping the sensor clean in the first place.  But I'm sure there are more forces at work that we have not yet considered here.

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Use one large ratio zoom in bad weather. 

  

Or use an SLT adapter and requisite lenses. 

  

Or use a straight thru adapeter and requisite

lenses but also suff a piece of colorless gel

filter in the tube. Stuff it anyway but parallel to 

the sensor to avoid reflections. 

  

Or ypu can carry 2 or 3 E-mount bodies with

lenses already in place.

  

If your adapted lenses are from an SLR, you

could skip theadapter and the Sony body and

just use the SLR.

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Little sideways on the topic here but...

I caved when I switched from DSLR to Mirrorless and updated my lens changing "workflow".   Now I use a large Giottos Rocket air blaster and blow off the camera, then then new lens, then take off the lens, blow off the sensor, blow of the new lens and attach it. Then I blow off the old lens and put the caps on and back in the bag. If I'm shooting in a dusty environment, I live in a desert, I 1st do the sensor cleaning operation, but rarely.  

Yes, it takes longer, but now I've got it down so fast that it's not much longer. And since I've started doing it I haven't had dust in any of 1000's of images. 

I hope there's a better answer in the future, and it's a trade off I'm willing to make to save the weight and get it IQ in such a small package.

 

Also, while I do carry primes, and use them, since I bought the 24-70 GM, I find that I'm changing lenses less and less. 

Other's suggestions here are great. 

 

 

My son is watching "Bob's Burgers" in the background and I just heard "when dust hits the ground does anyone hear it?" hahaha. 

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