Special steps for 550D Modification

 

 

***550D 12. In the photo below, the ribbon cable connectors are labeled "A" through "L" for reference. We will disconnect all of these ribbon cables in the next steps.

A. This is a "slider" type of ribbon cable connector, not a "hinged" type. Insert a toothpick in the small hole in the ribbon cable and wiggle the cable gently from side to side as you apply pressure away from the connector to pull the ribbon cable out of the connector:

B. This is a hinged type connector. Use a small flat head jeweler's driver to flip up the dark part of the connector which is hinged so that it moves up and away from the ribbon cable allowing the ribbon cable to be removed. Remove ribbon cable with rubber tipped flat head tweezers:

C. This is a "slider" type of ribbon cable connector. Insert a toothpick in the small hole in the ribbon cable and wiggle the cable gently from side to side as you apply pressure away from the connector to pull the ribbon cable out of the connector.

D. This is a "slider" type of ribbon cable connector. Remove ribbon cable with rubber tipped flat head tweezers.

E. This is a "slider" type of ribbon cable connector. Use the edge of a razor knife to loosen and remove ribbon cable with tweezers.

F. This is a "pop off" (plug type) connector. Lift it off with a tooth pick or your fingernail:

G, I, J, K & L. These are hinged type connectors. Use a small flat head jeweler's driver to flip up the dark part of the connector which is hinged so that it moves up and away from the ribbon cable allowing the ribbon cable to be removed. Remove ribbon cable with rubber tipped flat head tweezers.

H. This is a "pop off" (plug type) connector. Lift it off with a tooth pick or your fingernail.

All the ribbon cables "A" through "L" have now been disconnected:

There is one more cable connected to the upper right corner of the circuit board that needs to be removed. To get access to this connector, follow these steps:

13. Remove the diopter adjustment screw and cam:

14. Remove three screws as shown and remove the front camera cover:

15. Remove two screws on bottom of camera as shown:

16. Lift the camera bottom plastic up and over the metal tripod socket and push the front camera plastic part off:

17. Take top off camera to access the final white pull-out type connector. Disconnect this white connector on edge of circuit board with a flat head jewelers driver. Also note the black fiber optic cable that pulls out of a small white connector as shown below.

18. Place removed circuit board in a sealed container:

19. Remove two screws on grounding strap as shown below. The screw on left is covered with a black plastic tape. Lift the tape up with tweezers to access it.

20. Remove small ribbon cable using rubber tipped flat head tweezers:

21. The CMOS assembly unit is held in place with three Torx head screws that are also used for adjusting focus and tilt. These three screws may be fully seated or may not be and they need to be returned to their original position later in order to maintain accurate focus.

One way to do this is to place a mark on each screw head and note or mark its position. Turn each screw inward while noting how many turns until the screw is fully seated. During re-assembly you will need to fully seat the screw and use the mark as a guide for loosening the screw the correct number of turns for each screw.

Another way to do this is to etch a thin line on the black plastic pin that sticks up through the shim of each mounting screw. This etched line can then be used as a quide during re-assembly.

Another way is to measure the length of the black plastic pin that sticks up through the shim of each mounting screw and a make a guide that can be used during re-assembly.

Note: You may want to do all three methods above to improve the accuracy of returning the screws to their original position.

Clean the black adhesive from each of the three mounting screws with a razor knife and remove the three screws using a Torx T-7 driver. Be careful when doing this since the mounting screws are spring loaded and there are thin shims on each of the screws. The number and thickness of these shims is important to restoring the camera for sharp focus across the field of view, so be careful when removing the shims and note their location so that they are returned to their original positions. When the Torx mounting screws are removed the springs will also be loose so be sure they don't fall out of the camera.

Brent Maynard reports that a Torx T7 was not the correct size needed to remove his CMOS assembly screws, but a T6 size worked instead. He notes: "Canon could be using different sizes."

22. The next step is to remove the CMOS imaging chip/circuit board assembly. Be careful when removing it because there will be an exposed filter on the back side. The assembly needs to clear small black pins first to become totally free. Here is the assembly removed:

 

CONTINUED Next Page - Camera Disassembly Continued


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