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Flocking A Newtonian

How could I improve the overall performance of my 8 inch Newtonian without breaking the bank.  I had read several tutorials on flocking Newtonians and now it was my turn to give it a try.

 

Materials used

 

· Flocking paper, purchased from ScopeStuff.com

· Black Sharpie permanent marker

· Yardstick

· Scissors

· Exacto knife

· Masking Tape

          

Total cost of this project was $26

To me this was the moment of truth.  I brought the scope in from the garage.  Some quick math told me the 24” X 47” piece of flocking paper would cover the interior of the scope in one piece.  I would have to cut and piece it in. 

 

 

To save as much pain as possible I marked the primary mirror cell and tube with masking tape.  This would allow me to replace the cell the same way in the tube.  Hopefully this would minimize collimation issues.  I did the same with the spider and front edge piece of the tube.

 

 

This photo shows the marked spider and an idea of the reflective nature of the paint applied to the interior of the tube.  A flash was not used for this photo. 

 

 

So far, so good.  I removed the front end of the tube and spider.  Notice the reflective edges of the secondary mirror.  I wanted to minimize the effect of this. 

 

Next I removed the focuser and finder scope base.  I used a small plastic bowl to keep track of all the screws and small bolts.

 

I removed the primary mirror cell and mirror.  This was a good opportunity to really inspect the mirror.  I bought this scope used and was pleased to see no discernable flaws in the mirror.  I thought about blackening the edges of the mirror but decided against it. 

 

With the scope disassembled I measured out six inch strips on the flocking paper backing.  I went with six inch increments because I thought this to be the widest size I could apply without running into problems.  I decided to not attempt applying the paper length wise in the tube.  The major reason for this was my arm wasn’t long enough.

 

I worked the paper around the interior of the tube.  I did not want to pull the backing off all at once.  This would have made the paper to hard to control.  This technique worked well.  I applied about 3-4 inches at a time, pulling the backing as I went.  I made sure to have enough overlap .

Here you can see the finished product.  This picture was taken using a flash.   .

I had noticed what I thought to be a lot of reflection off the edge of the secondary mirror during collimation.  I blackened the aperture side of the secondary using a black sharpie pen.  I hope this will cut down the internal reflections I was seeing.

I reassembled and collimated the scope.  This photo shows how much the internal reflections had been reduced.  I cant’t wait to get it under a clear sky.

Since undertaking this project I have had the opportunity to test it under a clear sky.  My personal opinion says it was definitely worth the effort.  There was an increased contrast in every image I saw.  Saturn was unusually bright.  Well worth it.