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Hi Rod Apparently the EZ Focuser won't remove the mirror shift problem. It is inherant with most SCT focuser designs. The new RCX Meades get around it by focusing using the secondary mirror and not the primary. I found this quote on the EZ focuser site
quote
"Typically, another 8% of the focuser backlash is due to mirror shift. Your SCT’s primary mirror assembly rides up and down the scope baffle tube to achieve focus. The focus mechanism is attached to a point way out on one edge of the mirror assembly. If the mirror assembly doesn't fit tightly around the outside of the baffle tube, the mirror will "wiggle" a bit from side to side if you push and pull on one edge (which is what the focuser does). THIS WIGGLING IS WHAT WE CALL MIRROR SHIFT. You will be turning the focuser knob while the mirror is shifting, but since the center of the mirror isn't moving until the mirror has completely shifted, you will be experiencing focuser backlash during this period of time.
The EZ Focus kit does not address this secondary backlash source directly"
end quote
Glad the new kit does what its supposed to.
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