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bonzodog

Help focusing Phil Dyer Camera on SW 200p

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Hi..
I bought a PD Video Camera Dec. last year - to use on my SW 200p reflector - I would like some advise
on how to achieve focus - from someone who has succeeded on the SW 200p. i.e. what do I need to place in the
eyepiece to get the correct back-focus. I've tried loads of combinations to no avail..
even a sipmle pic. diagram - doing me head in.
kind regards.

 

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Most standard Newts have an issue with back focus.

This means that you cannot focus close enough to the focuser to acheive focus.

There are a few options.
1. Buy a low profile focuser - this MIGHT help and give enough back focus.

2. The standard Skywatcher focuser used to come with a removeable part (the part that the Eyepeices slot into), this left a T thread for use with camera. This often gave enough back focus - but you had to screw the camera into the T thread.

3. Move the mirror up the tube - I did this on a 150P - it worked really well, but it was a bit of work to remove an inch from the bottom of the tube and drill new holes and re-attach. Quite a scary thing to do to a nice shiny new scope. But it DOES work.

4. You could use a Barlow Lens. A barlow lens will increase the effective magnification of the setup - it has several effects. It increases image scale, lowers the speed of the scope (F5 to around F10 for a 2x barlow), but crucially it also moves the focus point out so you should be able to focus with your camera. 

Hope that helps. 

Ant

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ARGH - forget all that.. the dual Power/Video cable supplied was Faulty - just bought a replacement 10m BNC DC cable.. wallah focused puurfect.. - I could almost cry - months and months - all those clear sky sessions wasted trying to get an image on screen - all those various length focal adapters - all those un-answered support emails to Phil Dyer - whatever moving on..

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Lol - it won't be the last time a lead lets you down :)

Glad your focused OK now.

Ant

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On 28/10/2016 at 12:23, bonzodog said:

ARGH - forget all that.. the dual Power/Video cable supplied was Faulty - just bought a replacement 10m BNC DC cable.. wallah focused puurfect.. - I could almost cry - months and months - all those clear sky sessions wasted trying to get an image on screen - all those various length focal adapters - all those un-answered support emails to Phil Dyer - whatever moving on..

Hi Bonzodog. I had exactly the same problem as you, only i was using it with a Celestron C9.25 OTA. The cable was rubbish and i got a snowy signal until I bought a better quality cable. I also ended up having to buy a better USB video capture cable as that was also pants lol. Anyway glad you got it sorted!

Nuka 

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absolutely spot on - it's hit and miss.. if you can recommend a particular one let me know.. 

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the focusing solution is to get a C mount 0.5 focal reducer - actually managed some Moon images.. :)

photShop_01.jpg

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