Notes on changing the filter wheel:

1.  Make sure you know which filter wheel you are planning on putting into the camera, and also that you know which filters are in it.  For WySH, we have a text file saved on WIROPrime in the WySH directory.  ***You can't name two filters the same thing, or the GUI will get VERY confused!!***

2.  Under no circumstances should you touch any of the filters!  Check them for scratches and the fingerprints of others.  There should be some compressed air in the workroom which you will want to use to dust off the filters before (and probably after) replacing the filter wheel.  KimWipes are also at your disposal.  Handle the filter wheel as if your life depended on it.  One filter is worth a lot more than you if we broke you down into your chemical components (about $9), which is what will happen to you if you bust anything.

3.  Take off one side and the bottom of the light box.  Most likely, you will also want to take both bungee cords off so that you can move the filter wheel mount more easily.

4.  Now, there are two possibilities, but either way, this is always a two person job.

a.  There is already a filter wheel on the camera.
b.  There is no filter wheel on the camera.

If there is already a filter wheel on the camera:

1.  Loosen the 3 allen screws.  You can rotate the filter wheel in order to access them more easily.  As you rotate the wheel, you will hear/feel a click.  This is where the filter wheel locks into position.  It seems to be easiest if you rotate it slowly from position to position. 

2.  Before completely removing this wheel, you may want to make a mental note of where the filter positions are so that it will be easy to replace it with your filter wheel.  As you remove it, you can push back (slightly) on the dewar so that the filter wheel fits through enough to pull it out the bottom without scratching any of the filters.

3.  Putting your filter wheel on requires you to basically go backwards now from this step. 

If there is no filter wheel on the camera:

1.  Get the wheel onto the mount.  When doing this, push back (slightly) on the dewar in order to have enough space to slide the wheel through without scratching any of the filters.  Have one person identify the numbers 1 and 7 on the mount.  Have the other person identify those same filters on the filter wheel.  Get those filters lined up with their respective numbers on the wheel mount.

2.  There are 3 allen screws that you need to tighten.  You can rotate the filter wheel in order to access them more easily.  As you rotate the wheel, you will hear/feel a click.  This is where the filter wheel locks into position.  It seems to be easiest if you rotate it slowly from position to position. 

5.  Once you get the wheel on, it might be a good idea to use the compressed air once again to dust off the filters.

6.  Make 100% sure that both bungee cords are on correctly (see picture below), and close up the box.  You should probably test the filter wheel with the GUI to make sure it moves correctly between filters.  For WySH, it is easiest to move to V, which should have a dark blue/purple filter to the left (B) and an orange filter to the right (R), and then move all the way up to the WySH filters to make sure the wheel is moving properly.  This is sometimes even a good idea to do as part of the daily start up.

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