Amateur attempt at Antares 29 Apr 11

[Sivakis]

Good to hear you made a barndoor too!

I'm probably gonna start with a manual one but was wondering where I would buy a synchronous timer in Singapore for the 1rev/min motion. Wondering if it can be found at SLT.

[timatworksg]

Mine is manual driven too. With a 50mm lens it's 1/4 turn every 15secs with a 1/4"-20 Threaded Bolt. I made the curved drive rod version so no tangent errors.
But you could get motors from SLT...just need to add a PCM type circuit for control of speed. Or maybe grab a 2nd hand deal on some RA motor perhaps. In the midst of making a slimmer version and hopefully a motor to add on...also in the planning is a Tangent Arm version ala AstroTrac. Dunno if it'll work but I enjoy trying!

[Airconvent]

Congrats! You have taken your first steps....keep walking bro and taking photos bro!

[Sivakis]

Wanting to mount my DSLR to my reflector, I understand that this would require a suitable T-ring + T-adapter.

I'm concerned about exposing my camera sensor while taking the shot and I read that there are T-adapters that allow the fitting of a filter to prevent just this.

The T-ring is pretty straight-forward, but there's a lot of T-adapters out there and I'm pretty confused - which ones can accept filters, which cannot...... What would you recommend for me in this situation?

[Robin Lee]

Wanting to mount my DSLR to my reflector, I understand that this would require a suitable T-ring + T-adapter.

I'm concerned about exposing my camera sensor while taking the shot and I read that there are T-adapters that allow the fitting of a filter to prevent just this.

The T-ring is pretty straight-forward, but there's a lot of T-adapters out there and I'm pretty confused - which ones can accept filters, which cannot...... What would you recommend for me in this situation?

Exposing your camera while taking the shot? I don't quite get it. Could you elaborate?

What kind of filters are you looking for? Light Pollution? There are such filters that you can slip it inside the sensor chamber, namely Astronomik CLS filter.

As long as the T-adapter has an inner thread at the "nose-piece" end, then you can attach a filter onto it.

[Sivakis]

Ahhh hmmm, how to elaborate?

I may be wrong here, so bear with me if I am:
When I attach the T-ring+adapter to my camera, effectively it's a camera with no lens attached, ie:
Camera Body --> T-Ring --> Adapter
In this case, the camera sensor is exposed to dust yes? Unless the adapter is sealed off by a glass element (either built-in or filter).

I'm worried cos the sensor will be electrically charged when taking shots and this will attract dust particles.

Hope the above made sense.....

[Robin Lee]

Ahhh hmmm, how to elaborate?

I may be wrong here, so bear with me if I am:
When I attach the T-ring+adapter to my camera, effectively it's a camera with no lens attached, ie:
Camera Body --> T-Ring --> Adapter
In this case, the camera sensor is exposed to dust yes? Unless the adapter is sealed off by a glass element (either built-in or filter).

I'm worried cos the sensor will be electrically charged when taking shots and this will attract dust particles.

Hope the above made sense.....

Oh... you mean worry of dust getting in. There is less to worry if your camera has built in supersonic dust removal function. Though, prevention via an attached filter is better. And yes, you are right about the combination.

There are two alternatives for you. First is built in filter like the Astronomik CLS. Second, it's the filter attached via a T-adapter. The second is probably better since the 2" filter can also be used for other observing applications such as attaching it to eyepiece.