webcam + 10" DOB

[RolandKol]

Hi guys,

 

I have Skywatcher DOB 250 Flexitube GOTO and recently noticed HD webcam in my friend's place...

(AUSDOM AW615 1080P Full HD 12.0M USB2.0)

 

So I received it for few of beers and managed to place it into 1.25' EP holder without any struggle.

 

I haven't removed any filters from webcam, just wanted to see if it will fit in and it did, so I was really happy, but...

 

(unfortunately word "but" always comes after word "happy"),

 

but... the only thing I can see on the screen is my Primary and Secondary mirrors

I think, this webcam would be perfect for collimation however, what to do next? 

I want to see something more than just mirrors, - Moon and Jupiter maybe...

I tried to attach 2'' adaptor which comes by default with the telescope to increase the distance between mirrors and webcam... the result is the same.

 

I also used flexitube ability to shorten the tube and reduce Focal length, - no result, just the size of the image is different.

 

Should I try Barlow?

 

 

[Cornelius Varley]

You will need to remove the webcam's lens to get it to work. With the webcam's lens in place you will only see the secondary and primary. You will also need to either rehouse the webcam in a suitable box and add a 1.25" nosepiece.

[RolandKol]

24 minutes ago, Cornelius Varley said:

You will need to remove the webcam's lens to get it to work. With the webcam's lens in place you will only see the secondary and primary. You will also need to either rehouse the webcam in a suitable box and add a 1.25" nosepiece.

 

yep... silly me, - it works without lens ...

thanks

[RolandKol]

My Jupiter

 

Does not look good at all... the dot in the centre, looks like the secondary mirror...

sadly, I woke up too late and had no time to experiment properly...

 

It was with Focuser full way in, otherwise I could not see anything....

 

We have no moon at the moment, so I could not try out on it...

 

Neighbour windows are more or less in focus, but they are only in aprox 500 metres distance.

 

 

[Cornelius Varley]

The camera is too far away from the point of focus so hat is why the image is blurred. You can use a barlow lens to move to point of focus outwards sufficiently to achieve focus.  The video shows how to attach a dslr to a Newtonian shows the principle of how the barlow fixes to problem.

A couple of photos of how you are attaching the webcam to the focuser might be helpful.

[RolandKol]

Thanks for a nice video Cornelius Varley, it explains everything I need.

I have read about Barlow previously, but I was confused as I had quite a good focus on neighbour windows.

I hope I will receive Barlow quite soon, to experiment further.

While I wait, I will try to attach webcam directly into 2" holder somehow (as it will bring the webcam much closer to the tube), - maybe it will help... As I afraid, I will not be able to keep Jupiter in target with higher magnification.

P.S.

"A couple of photos of how you are attaching the webcam to the focuser might be helpful. " - I simply stick webcam into EP holder instead of the EP, - it fits in quite modestly without external focuser ring.

(it has internal focuser ring which is probably 1.24" diameter which sticks out from the webcam body for around 0.12", so the EP holders are able to catch it, - it is not perfect, but good enough for initial experiments).