Try taking a picture (I realize that you cannot “see” what you are taking) and then download it to a computer.
''If the picture on the computer is OK'' then most likely you have a motherboard problem in the camera that is not allowing the image being “seen” by the camera’s CMOS image sensor to be transferred to the camera’s display screen, which you say is still working. (can you view the menu screens OK?)
''If the picture on the computer is not OK'' (perhaps just a black image) then most likely you have a CMOS image sensor problem or a motherboard problem or both.
Replacement [https://www.ebay.com/itm/Canon-EOS-70D-Camera-CCD-Image-CMOS-Sensor-Assembly-Replacement-Repair-Part-/371920600725|CMOS image sensors] are not cheap. (Although if this is the problem you may find one cheaper ;-)
=== Update (10/02/2018) ===
-
Hi @emilysmith ,
-
Perhaps the card slot is the problem by not detecting the presence of a card (have you tried a different one?)
+
Having now seen, after your update, that the “white screen” you mentioned is actually an error message perhaps the card slot is the problem by not detecting the presence of a card (have you tried a different one?) and not what I suggested above
If it is not detecting the memory card, perhaps that is why you cannot see an image. No point showing you a new image if you cannot "save" it to anywhere.
This is just a guess on my part and may be totally wrong
Try taking a picture (I realize that you cannot “see” what you are taking) and then download it to a computer.
''If the picture on the computer is OK'' then most likely you have a motherboard problem in the camera that is not allowing the image being “seen” by the camera’s CMOS image sensor to be transferred to the camera’s display screen, which you say is still working. (can you view the menu screens OK?)
''If the picture on the computer is not OK'' (perhaps just a black image) then most likely you have a CMOS image sensor problem or a motherboard problem or both.
Replacement [https://www.ebay.com/itm/Canon-EOS-70D-Camera-CCD-Image-CMOS-Sensor-Assembly-Replacement-Repair-Part-/371920600725|CMOS image sensors] are not cheap. (Although if this is the problem you may find one cheaper ;-)
+
+
=== Update (10/02/2018) ===
+
+
Hi @emilysmith ,
+
+
Perhaps the card slot is the problem by not detecting the presence of a card (have you tried a different one?)
+
+
If it is not detecting the memory card, perhaps that is why you cannot see an image. No point showing you a new image if you cannot "save" it to anywhere.
+
+
This is just a guess on my part and may be totally wrong
Hi @emilysmith ,
Try taking a picture (I realize that you cannot “see” what you are taking) and then download it to a computer.
''If the picture on the computer is OK'' then most likely you have a motherboard problem in the camera that is not allowing the image being “seen” by the camera’s CMOS image sensor to be transferred to the camera’s display screen, which you say is still working. (can you view the menu screens OK?)
''If the picture on the computer is not OK'' (perhaps just a black image) then most likely you have a CMOS image sensor problem or a motherboard problem or both.
Replacement [https://www.ebay.com/itm/Canon-EOS-70D-Camera-CCD-Image-CMOS-Sensor-Assembly-Replacement-Repair-Part-/371920600725|CMOS image sensors] are not cheap. (Although if this is the problem you may find one cheaper ;-)