Filter/Imaging Chip Assembly
Resting above the CMOS imaging
sensor are two filters. The frontmost filter is Low-pass Filter
#1 (LPF#1). The filter below it is Low-pass Filter #2 (LPF#2).
LPF#2 is the "IR Cut filter" that needs to be removed.
Canon made a change from previous models in that both of these
filters are glued into the plastic filter frame, instead of only
one being glued and the other held in place with a metal clip.
We are going to remove and replace
the "IR Cut Filter" only. The "Low-pass 1"
filter will be left in the camera so handle it carefully.
22. Remove two screws at the locations shown
below. Lift one corner of the metal frame up with a small jewelers
driver and pop the metal frame off. Be careful not to scratch
23. Now we will separate the filter assembly
from the CMOS imaging chip. The black filter assembly is held
on to the surface of the imaging chip by a thin strip of double-sided
tape. This adhesion can be weakened by using an exacto razor knife.
I used a flat "Chissel" type razor and patiently pried
between the black plastic frame and the metal base, all around
the unit as shown. There are two pins that position the frame
correctly. Once loosened, lift the filter assembly to remove it.
Place the CMOS imaging chip into a sealed container to keep it
dust-free as you continue to work on the filter assembly. During
these steps, make sure all optical surfaces are kept free of dust
and clean with a blower's bulb if needed.
24. Low-pass filter #1 is glued inside the
plastic frame at four locations shown by the yellow arrows in
the photo below. Use a razor knife to cut the adhesive along the
side edge of the filter glass at these four locations. Use a small
flat head driver to pry the filter up as shown in the photo. Work
your way around the entire filter, applying only a little pressure
to work the filter free. Do not apply too much pressure in order
to avoid stressing or breaking the filter. Some adhesive is under
the filter's edge so the filter needs to be worked loose by prying
it up. When the filter is loose, remove it, wrap it in lens paper
and place in a container for protection.
25. Remove the original IR Cut Filter (blue
glass) from its frame. It is glued in the plastic holder at the
four corners. Use a razor knife to loosen the glue in each corner.
Pry the glass up at each corner. If the filter breaks, no problem
since the filter will be discarded.
26. You can use nitrile gloves to apply pressure
on the filter to help remove it from its frame to avoid breaking
27. Glue the replacement Baader filter into
the plastic frame by using very small drops of silicone glue in
each corner. Be sure to use a glue that doesn't outgas as it may
affect the optics. Do not use much glue here so that it doesn't
run into the field of view. I left the glue dry overnight to be
sure it was well cured. Below is the plastic frame with the new
Baader filter glued into place.
28. Glue the original LPF#1 filter into the
plastic frame by applying silicone glue at the four locations
marked by yellow arrows in the photo below. There are small wells
there that will hold the glue. As was done for gluing the LPF#2
filter, be sure to allow the glue to dry overnight to be sure
it is well cured. Below is the plastic frame with both filters
glued into place.
The disassembly and filter replacement
are now completed. If there is any dust on the filter you can
remove it with a blowers bulb or flick it away with a camel hair
brush or the end of a microfiber lens cleaning cloth. On the next
page, you can continue to follow re-assembly directions that should
be easy since you'll be going through the above process in reverse.
CONTINUED Next Page - Imaging Chip Re-Assembly
If you completed the modification
and would like to let me know how it went for you, you can contact
me at the following email address:
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modification instructions that might be helpful to others and
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