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Filters and O rings on the FW8G-STT filter wheel.

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#1 DJohnson


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Posted 10 May 2013 - 08:47 PM

I recently purchased the above filter wheel for my STT camera, and am slightly confused at the instructions concerning the O-rings and filters.

I have a set of LRGB and Ha filters from Astrodon. According to that site the filters are 3mm thick. By the SBIG instruction manual, I should put one of the supplied O rings, then drop in the filter, and then put back on the filter retainer plate.

When I do that, the filters stick up above the surface of the filter wheel by a non insignificant amount. When I try to put back on the filter retainer plate, and because I am only using 5 filters, the retainer plate does not sit 'flat', and some of the filters, (namely those adjacent to the empty filter holes) look to be slightly tilted in their seats.

I removed the plate, pulled out the filters and reinserted them, sans o rings. Now, the retainer plate will reattach flush with the filter wheel, but the filters themselves appear to be a tiny bit loose. When I used some compressed air to clean them off, I could see them very slightly moving in their seats.

I appreciate any and all assistance in this manner.

#2 Joe C

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Posted 16 May 2013 - 10:38 AM

In my FW8-ST8300, I placed my filters in the wheel then the o-rings then the filter retainer. That way, the filter retainer, when not sitting flat still holds onto the filters but only contacts the o-rings. This allows for the filters to have a full contact on the wheel and the retainer to have multiple contact points on the o-rings.

#3 Amletico


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Posted 29 June 2013 - 01:21 PM

Hello DJohnson
I have a problem very similar;
I use a FW8G-STT wheel, and 3 Astronomik filters, and they are only 1 mm thick;

1) when I insert only 1 o-ring, the filter is very loose: it makes a lot of vibration and noise while the wheel is rotating !
2) when I insert 2 o-rings,(the filter is put in the middle of them) the upper oring sticks above the surface, and filter retainer plate is impossible to close.

How did you solved the problem ?
I used the original SBIG o-rings, and you ?

I will appeciate any help !



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