Help Canon Rebel T7

[clementecamaril]

I need help, I've tried everything on youtube and the internet, and I'm sure someone has already had this problem before. Anyway, I know I messed up and shouldnt have done it, but I got frustrated because I could see some fibers through my lenses, and I thought it was my camera, so I removed the lens and cleaned it with a swab. Now, I cannot get focus on my viewfinder; I've tried everything. I've moved the diapoter, the autofocus, changed eyes, etc. However, when you put it on the screen, it does work and focuses well. Please help someone; I'm getting frustrated

[Tronhard · Accepted solution]

Hi and welcome to the forum:

If you had fibres that were visible, almost certainly they were on the base of the pentaprism or on the mirror - a foreign object on the lens is extremely unlikely to show.  You say you swabbed the lens, did you also attempt to swab inside the camera body, or have difficulty in seating the lens back in? 

Given, as you say, the images look ok through the rear LCD, but you cannot see through the viewfinder, I suspect you have displaced the mirror and it is no longer reflecting correctly through the pentaprism to give a sharp image in the viewfinder.  When looking though the viewfinder the image you see is reflected into the pentaprism by the mirror in the camera body, but through the LCD screen the mirror is flipped up and the image sent to the screen is from the sensor, which would be why the image appears ok when you are looking at the rear LCD.

I would suggest not playing further with this yourself, but take the camera to a reputable store and see if they can confirm this, and if necessary, relocate the mirror.  It's a fairly simple fix, but best left to a skilled techie.  They can also remove the offending object if it is still there.

[Tronhard · Accepted solution]

Hi and welcome to the forum:

If you had fibres that were visible, almost certainly they were on the base of the pentaprism or on the mirror - a foreign object on the lens is extremely unlikely to show.  You say you swabbed the lens, did you also attempt to swab inside the camera body, or have difficulty in seating the lens back in? 

Given, as you say, the images look ok through the rear LCD, but you cannot see through the viewfinder, I suspect you have displaced the mirror and it is no longer reflecting correctly through the pentaprism to give a sharp image in the viewfinder.  When looking though the viewfinder the image you see is reflected into the pentaprism by the mirror in the camera body, but through the LCD screen the mirror is flipped up and the image sent to the screen is from the sensor, which would be why the image appears ok when you are looking at the rear LCD.

I would suggest not playing further with this yourself, but take the camera to a reputable store and see if they can confirm this, and if necessary, relocate the mirror.  It's a fairly simple fix, but best left to a skilled techie.  They can also remove the offending object if it is still there.

[clementecamaril · Accepted solution]

Thank you Trevor , yup that’s exactly what it’s doing and exactly what I think happened. Yes I will definitely take it to someone that knows from know on.