Used the first contact cleaning material on a little C6 sct. I removed the corrector plate and primary mirror and was able to give all the elements a good clean. The material does a good job , as noted in the instructions water spots might need more attention but dust is removed completely. Probably the biggest thing is allow adequate time for the material to dry before removal. The secondary had flocking on the baffle tube , not sure if it's standard or the previous owner had installed it but the secondary mirror was very dull, maybe vapour from from the flocking sticky side. First contact really cleaned it up well 🙂. Apart from the drying ,using o-rings (made of epdm material) as demonstrated on their website to prevent runoff is something to be aware of and maybe practice before cleaning a apo refractor .
