There comes a time when everyone has to clean their corrector plate. As it's exposed to the elements
it will collect dewdrops, bug poop and dust. To clean it is not a large problem as long as you are
prepared ahead of time and take some care.|
Both of the following cleaning solutions work, I prefer the Windex one.
Cleaning solution #1
500 ml 99% isopropyl alcohol
Dawn dish soap (or another detergent with no citrus extract, fragrances etc)
Cleaning solution #2
1 bottle original Windex with ammonia (no vinegar)
Firstly get your supplies ready. You'll want to get a large wad of cotton surgical cotton. If you can't, then get cotton balls or white, unscented Kleenex (my favourite). For your cleaning solution you'll want a 1 litre mason jar or squirt bottle and some coffee filters.
To prepare your cleaning solution clean thouroughly your bottle. Then run the distilled water and (if you're using it) the Windex through seperate coffee filters and mix your solution. If you're using Windex it's a 50:50 solution, if you're using the alcohol it's 250ml of alcohol, 750ml of distilled water and ONE DROP of dish soap.
To start, remove the retaining ring that holds the corrector in place. On a C8 this is a plastic ring held by six small hex screws. Taking care not to put any thumb-prints on the glass take out the screws and put them in a safe place.
Now, there should be a piece of white paper around the edge of the corrector somewhere that shows how it has to be aligned. This should be next to the serial number etched along the edge of the corrector. Use a pencil and mark the metal ring of the cell where the factory mark is just in case it falls out. Also look for any cork spacers and/or paper shims that were put in at the factory. Note their locations with pencil so that they can be replaced correctly. They all tend to fall out when you pull the corrector plate out.
Next you'll want to carefully lift out the corrector by the secondary holder. If it's a bit tight give it a soft wiggle until it pops free. Now lay the corrector down on a clean surface standing on the light shield around the secondary mirror.
Check the spacers. If they're still there OK; if not replace them. Use a small touch of craft glue to hold them in place. They had a pre-stick backing that may have worn out.
Holding the corrector by the secondary on an angle flood 1/2 the corrector with the cleaning solution. Use handfuls of cotton (Kleenex if you're using it) to carefully move off any residue. Change the cotton often and don't press at all, just use the pressure of the cotton. Now turn the corrector 180 degrees and do the rest of the same side. When you're done flood the corrector with plain distilled water to rinse it turning it as you go so rinse the whole surface.
Any droplets left can be lifted with kleenex or paper towel. DON'T WIPE, just lay it flat (better if it's folded 4 times for softness) and lift up the water.
Repeat on the other side of the corrector.
When the corrector is clean replace it in the cell, between the spacers with your mark aligned with the serial number. Then carefully replace the retaining ring and put the screws in. Don't tighten them a lot, just finger tight with the short end of the allen key for torque. Like a tire, criss-cross from screw to screw to get an even tension.
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