William Optics GTF81 APO arrived today at last - hooray!

[choochoo_baloo]

This instrument arrived from the USA today, after being released from HM Customs. Am very excited about venturing into astrophotography properly now. What would be the first things others would attempt to photograph with it?

[Atreta]

You could try the milky way or the moon and planets, but i think the moon will be a better target to start.

don't know much about the gtf81 but the focal length is a bit more than the one i use, so the planets magnification

won't be that high unless you use a barlow.

the milky way is a very nice start too.

[tingting44]

forget the moon and planets!!!! with a scope like this get guiding and get some Deep sky objects!!! the veil, the iris neb, andromeda (low), M33 a bit lower... plenty to choose from in the Cygnus area  

[Alien 13]

If it was me i would go for the moon 1st just to get a feel of how well the focusser behaves with a load and its position as well as getting the general scope balance set up.

Alan

[wuthton]

forget the moon and planets!!!! with a scope like this get guiding and get some Deep sky objects!!! the veil, the iris neb, andromeda (low), M33 a bit lower... plenty to choose from in the Cygnus area

My thoughts exactly, jump in the deep end!

[Astrosurf]

What a lovely scope! If you have an iPad / iPhone, download SkySafari Plus. It gives you a list of 'Tonight's Best' objects. Then you can double check on Google which ones you'd like to try. To see how the object will fit your field of view, input your scope and camera in this:

http://www.12dstring.me.uk/fov.htm

He's currently working on a new version with NGC numbers.

Or you can check this site : http://dso-browser.com/

I like this too: http://en.wikipedia.org/wiki/List_of_Messier_objects

Good luck!

Alexxx

[choochoo_baloo]

Thanks all.

Have just located the focal plane of the scope with my Canon 450D, sadly it is beyond furthest travel of the telescope focuser.

Though the end focuser surface to cameras steel lens plate separation is only about 15 mm. Obviously it would be preferable to use a long enough T adapter and t ring, instead of buying a shorter T adapter + extension tube + T ring. The fewer joints sturdier the whole thing will be.

From the image it looks like the Skywatcher 2 inch T adapter would be sufficient: can anyone confirm the length of increased optical train? Looks to be about 1 inch, but I can't find any specs or drawings for it so would like a value for increase in optical train.

Thanks in advance.

[Alien 13]

I cant comment on your specific scope but you normally require 2" of extension to allow for the removal of a diagonal i use the WO  camera adapter to a std t ring on the camera.

Alan

[wuthton]

I cant comment on your specific scope but you normally require 2" of extension to allow for the removal of a diagonal i use the WO  camera adapter to a std t ring on the camera.

Alan

As above 2" ish, you are better off with some extra rather than having the focuser close to full extension.

[tingting44]

what mount have you got, and are you guiding?

[choochoo_baloo]

what mount have you got, and are you guiding?

Celestron AVX, yes will be guiding.

I gather the WO 2" extender would be the best choice?

[m37]

Dude, that is a beautiful scope. The new R&P focusers on those WO fracs are just dreamy. I binned my motor focuser because I just didn't need it with the fine focus knob being so smooth.

Sweet.

[choochoo_baloo]

Cheers m37; I'm a firm believer in spending/saving a bit more to get an excellent product 

Not had first light with the bad boy yet, though must admit to having spent a good 10 mins just watching the fine focus knob whirling around.........

[Christopher Davenport]

Thanks all.

Have just located the focal plane of the scope with my Canon 450D, sadly it is beyond furthest travel of the telescope focuser.

Though the end focuser surface to cameras steel lens plate separation is only about 15 mm. Obviously it would be preferable to use a long enough T adapter and t ring, instead of buying a shorter T adapter + extension tube + T ring. The fewer joints sturdier the whole thing will be.

From the image it looks like the Skywatcher 2 inch T adapter would be sufficient: can anyone confirm the length of increased optical train? Looks to be about 1 inch, but I can't find any specs or drawings for it so would like a value for increase in optical train.

Thanks in advance.

You could look at focal reducing and flattening which will speed it up and allow for focal point to be closer in.