SCB 2000 New to this and need advice

[SupahNube]

Hey guys.

Name is James, new to all of this VA stuff and have been running into several problems that im hoping you can help me with.

Last night i had a nice clear night so i got the scope and Sammy out for the first time to try my hands on Video Astronomy.

It did'nt go very well as i ran into various problems

The first problem is the FOV. The Sammy acts like a 6mm eyepiece which is very slow and narrow. I used a 0.5x reducer which i connected to the end of the 1.25 nose-piece adapter which connects to the cam. I then place the cam into the scope.

The FOV is still very narrow and still tiny... am i connecting it together right or do i need a different reducer? Or do i need another reducer and a spacer?

The other problem i had was with Hot pixels on screen which seem to be in the same place every time can i get rid of these somehow?

The last problem i had was getting the whole thing into focus. I could see some very blurry stars trailing across the screen leaving streaks. I dont have tracking on the scope as my Dec and RA motors are broken. Is there another a way to solve this? or do i need to fix my tracking?

Can anyone help?

Thanks.

I

[Psychobilly]

Hi James , Welcome to the VA sub board

You will need to fix the tracking  to stop the smearing...  you should only need to sort out RA tracking if it's on an EQ mount...

How are you displaying the output of the Camera ? is it straight onto  a  video monitor or is it on  a computer via a capture device? If it's a computer what software are you using?

Sorry to answer your questions with more questions

I had re-created the Focal Reducer thread here's a link to it... Sorry it's a terrestrial target rather than Celestial.....

http://stargazerslounge.com/topic/115811-samsung-scb-2000-with-sct-reducers/

Peter...

[DoctorD]

Hi James

Welcome to the group.

Unfortunately narrow field of view is one of the prices we pay for using relatively low cost CCTV cameras. You have not mentioned what scope you are using - you may be able to get a little more reduction if you can increase the distance between the reducer and the camera but do not expect big changes - also the greater the reduction the more inwards focus travel you will need on your  scope and this may also become an issue.

If you have no RA drive then try reducing the SENSUP or manual exposure to no more than x12 - this should give about half a second update (if you turn the SSNR to OFF). The camera is not operating at it's most sensitive but you will begin to see things that you cannot see with the naked eye.

As Peter mentioned, RA drive is pretty much essential if you are going to set the exposure to anything more than 1 second (the SC2000 at x512 will give you about 10 seconds and you will really begin to "see" stuff that you cannot with the naked eye). 

Hot pixels are another one of the things that we have to put up with - you can get rid of them is you choose to process the captured video later, but it's difficult to do "live" - I use an app called Camtwist for OSx which can subtract a "dark frame" in real time and reduce the appearance of hot pixels.

Virtualdub is a similar application for Windows and is used by some people who broadcast on the Night Sky Network - I have not used it myself.

I suggest you get the basics working before you consider further processing - getting the tracking working on your mount is probably the first thing to tackle.

Have you removed the IR filter from your camera - it will make it more sensitive but will mess up the colour balance if you use it in daylight?

Let us know how you get on and don't be afraid to ask for help - we're all learning here too

Clear skies

Paul

[SupahNube]

Hi guys thanks for the nice welcome and your sound advice.

Sorry i should have let you know what scope i am using...silly me. Its a Meade Lx10 pretty old but still a good scope it comes with the fork mount but the tracking is broken.

The RA motor works but there is a small cog at the back that wont latch to the RA adjustment nob. I tried to glue it on but it didnt work. Im sure i can fix that but if i cant is there an alternative RA tracking method or will i need a new mount?

Im using a computer screen with a capture card at the moment and using SharpCap Software which seems to be good but is there any better software i could use?

Peter - that link you sent me is perfect and lets me know what i need to get the right amount of reduction on the Cam. Thanks  

DoctorD - Thanks for the tips ill try using at Sens x12 while the RA tracking is out. Ill remove the IR filter, i wasnt sure if it would make a diffrence to the sensitivity but if it does consider it gone.

Thanks Guys 

[Psychobilly]

Ideally you want to be using the scope in Equatorial mode -  with a fork mounted SCT this means using a wedge and polar aligning the mount..

If your handy with the tools you can knock something together from Plywood which would probably be OK for the relatively short stacking time you get with the Samsung cams...

If you use if in alt/az mode you will need to get both drives working and field rotation  becomes an issue but again will probably be ok for the short stacked exposures...

Peter...

[DoctorD]

Hi James

If you have an SCT you should look out for an F3.3 focal reducer - I use one with my C8 and my Skymax 102.

Have a look at my gallery to see what's possible (my SDC435 is exactly the same as your SCB2000).

However. You should still get good results with the x0.5 reducer.

I use my C8 on a Minitower and don't find any issues with field rotation, however Peter is right, if you use the scope in AZ mode you will need to get both drives working.

Let us know how you get on.

Paul

[Dragon Man]

G'day James. Yep, as Paul says, you'll need a 3.3 Focal Reducer because you are using a Loooong focal length scope (a 'slow' scope)

To make the scope into a 'fast' scope the focal reducer effectively reduces the focal length.

Don't worry about suffering Field Rotation with Video Astronomy. The exposures aren't long enough to see any. Quite a few people use their AstroVideo cameras on Alt-Az mounts.

And welcome to Video Astronomy 

[SupahNube]

Hi guys 

Thanks a lot for the replies.

Im looking into getting an f3.3 reducer however i just want to make sure that my setup is right before i go any further. Im not 100 percent sure about how im fitting the cam to the scope and want to make sure that im doing it properly before buying anything else.

here's a rough example of how im attaching  the cam to the scope

Also i do have An EQ wedge for the mount so its just a matter of getting the RA motor working.

Anyone know anything about the old LX10 RA drive? Ive opened it up and there's pretty much nothing inside apart from a wee chip and a cog, it seems to me that the motor isnt getting any power. Its running off a battery which ive replaced but still no luck. broken fuse perhaps?

[DoctorD]

Hi JAmes

That looks spot on - if you get the F3.3 reducer you will need to put it before the 1.25" Visual back on the scope - have a look at my set up:

This is on my little SW MAK but the principle is the same on an SCT .

With the reducers the distance from the reducer to the CCD chip sets the amount of reduction you get, however with the stronger reducers such as the F3.3 if you go much outside of the design parameters you begin to get distortions.

Sorry I cannot help with the LX200 RA drive - might be worth posting in the Mounts section for help?

Clear skies

Paul