Help Imaging Venus

[Sunshine]

Gave Venus a go with the new refractor tonight, the 115mm 805mm FL Eon, using my old Neximage 5 which i used with satisfying results with my 15mm mak with much higher focal length. Unfortunately this camera does not jive so well with my frac, i didn't have enough travel on the focuser but, moving the camera out just a half inch did the trick and i was able to focus. Venus was very small, using a barlow was out of the question as i would have needed another 6 inches of draw tube to focus. I am assuming this is not the right camera for this scope, or, am i missing something? should i be using an extender tube before between camera and focuser to give me extra room for focus?. Also, is there a way to magnify Venus more without running into the  issue where i don't have enough focus travel?.

Edited April 11, 2020 by Sunshine

[Sunshine]

I'm a bit surprised an imager hasn't weighed in on this lol.

[misterp]

Have you a diagonal to increase the draw tube length?

Ian

[CraigT82]

On 11/04/2020 at 02:43, Sunshine said:

Gave Venus a go with the new refractor tonight, the 115mm 805mm FL Eon, using my old Neximage 5 which i used with satisfying results with my 15mm mak with much higher focal length. Unfortunately this camera does not jive so well with my frac, i didn't have enough travel on the focuser but, moving the camera out just a half inch did the trick and i was able to focus. Venus was very small, using a barlow was out of the question as i would have needed another 6 inches of draw tube to focus. I am assuming this is not the right camera for this scope, or, am i missing something? should i be using an extender tube before between camera and focuser to give me extra room for focus?. Also, is there a way to magnify Venus more without running into the  issue where i don't have enough focus travel?.

Well the frac will be designed to be used with a diagonal so that's where your lack of out-focus is coming from. Could either use camera in the diagonal or use an extension tube? 

[Sunshine]

7 hours ago, CraigT82 said:

Well the frac will be designed to be used with a diagonal so that's where your lack of out-focus is coming from. Could either use camera in the diagonal or use an extension tube? 

Great point, my mistake was I removed the diagonal and inserted the camera, thanks.

[Tommohawk]

On 11/04/2020 at 02:43, Sunshine said:

Venus was very small, using a barlow was out of the question as i would have needed another 6 inches of draw tube to focus.

A barlow will need to intercept the light cone before the focal plane, so if anything it should reduce the extension of the focuser. Of course you will need separation between the barlow and the camera so overall the camera will be further away than unbarlowed. Does that make sense?