What happened to my sensor?

Was shooting in burst mode, EOS T4i, and suddenly noted a black band on corner of last images.
Noting wrong with lens but on checking, the sensor, noticed a black rectangular piece that is free on one end and moves (rotates to some degree). It can manually be pushed back under lower frame but will come back with next few shoots.
Surprisingly everything else is working fine, including normal metering in various lights and shutter speeds.

Below is images of the this thing over the sensor and resulting images.

Any idea what has happened and anything I can do to spare an expensive repair center visit (That may actually cost me more the price of a new / refurb camera)?

That looks to be a shutter blade.

Exactly what I thought but then, if one of the blades is missing, how is that exposure in various light condition is still fine and unaffected?

I know what it is...

... a good excuse to order the 5D Mark III you've been thinking about.

samsen wrote in post #17760252
Exactly what I thought but then, if one of the blades is missing, how is that exposure in various light condition is still fine and unaffected?

depends sometimes which curtain is affected as to how bad the shots look.
Either way you've broken a shutter - quick check online and looks like the part itself can be had for as low as $40 so I'd be getting it off to Canon for a quote before deciding whether to proceed or not with repair.

Certainly stop using the camera as a broken shutter leaf could start causing other problems...

Considering the price of the repair will probably be in to $250-400 price point, it may indeed be time to get a new camera. There are 15% off coupons from the canon refurbished store right now.

Thanks every one for your time and worthy input.

Yes seems the inevitable has happened and this is one is best to be called RIP as after watching this shutter repair (1D n) --L-I-N-K-- that comes in three part and about 40 minutes running time (Including fast forward shooting) the end result is goose bumping only to me. I doubt if T4i is any significantly simpler to get into shutter.
I guess there is no chance of repair in DIY fashion, based on this review.
Then repair seems to be in $500 range! by repair center.

With the current triple discount coupon, and other sales, I did manage to get a T5 (not T5i) with two lenses including a nifty fifty for $250 (Including tax and shipping). So not bad but I am going to miss the Touch Screen and articulated LCD of this one...

Now last question:

Should I put it on sale at ebay for "Part Only" disclosing the flaw, that I see should bring about $150 or so, to me (After deduction of sale cost) or is there a hope to use it only for Astrophotography where I really do not need the accurate blades of shutter when most exposures are going to be 30 sec or more/time-lapse that will kill shutter count of other cameras? Till it die in harder way. That is if I can get rid off this, one loose blade. May be I can shave it with out damaging the Lowpass filter or forcefully pull it out!
Any thought?

samsen wrote in post #17761339
Now last question:

Should I put it on sale at ebay for "Part Only" disclosing the flaw, that I see should bring about $150 or so, to me (After deduction of sale cost) or is there a hope to use it only for Astrophotography where I really do not need the accurate blades of shutter when most exposures are going to be 30 sec or more/time-lapse that will kill shutter count of other cameras? Till it die in harder way. That is if I can get rid off this, one loose blade. May be I can shave it with out damaging the Lowpass filter or forcefully pull it out!
Any thought?

Always be honest and disclose everything when selling, otherwise you could end up being out the camera and money, and disputes, etc. Nobody is going to really shoot this with a loose shutter blade, because invariably it will damage the sensor/AA filter. Just list it as For Repair/Parts in your listing and put your pics that you posted here. Just say the camera works wonderfully except for the shutter failure. The alternative is to tear the camera apart and sell the parts yourself, you might get more, but it is more hassle.

If the camera can't be used as-is (it shouldn't be, anyway), AND you have already gotten another camera, get the $40 part and try to repair it yourself. You said you'll miss the touchscreen. At least if you mess it up, you already have another camera. If you are successful, then you have two cameras and some intimate knowledge of the inner workings. This is what I would do, but I love to take things apart and put them back together.

I always end up with that extra screw, though. Always.

MedicinSC wrote in post #17761438
If the camera can't be used as-is (it shouldn't be, anyway), AND you have already gotten another camera, get the $40 part and try to repair it yourself. You said you'll miss the touchscreen. At least if you mess it up, you already have another camera. If you are successful, then you have two cameras and some intimate knowledge of the inner workings. This is what I would do, but I love to take things apart and put them back together.

I always end up with that extra screw, though. Always.

That could be fun, and I would probably do this too. The worst case is that I would have various parts I could sell, like the LCD, outer shell, etc.

Sorry your camera broke. May I ask how many shutter actuations?

TeamSpeed wrote in post #17761456
That could be fun, and I would probably do this too. The worst case is that I would have various parts I could sell, like the LCD, outer shell, etc.

+1, sounds like fun to me!