HELP! Newbie. Blurry view in eyepiece for Celestron Astromaster 70eq Telescope?

[DaveMoss]

Hi all, Another newbie here - I found this forum after searching for help with my out of focus Celestron Astromaster 70eq. I’m not sure if this original issue was ever resolved but I’m having similar issues with my focus, I’m wondering if anyone had any ideas?

 

I bought the telescope brand new a week ago and was able to view the moon no problem. As I took it out the garage for a second I stupidly managed to knock the telescope (I think the erect image diagonal hit the wall). Now I am unable to get clear focus on anything, even when looking at a house 1km down the road through the full range of focus.

I can’t see that anything is damaged (it wasn’t knocked very hard) and both eyepieces are fine. 

When I remove the eyepiece and look directly down the erect was image diagonal I just get blur, however when I move my head up about one foot away from where the eyepiece goes I can see the image clearly in focus (though my eye is now at a distance from the eyepiece part). It feels like if the focus knob could keep moving the device outward it would eventually focus, but all I’m getting is a smudged image. 

I managed to get Venus centered last night, but no matter how much I played with the focus it just moves in and out of being more/less in-focused.
 

Any ideas on what might resolve this, or does it sound like I’ve broken something and need to send it back?

 

Thanks for any advice!

 

Dave

[RT65CB-SWL]

Hi @DaveMoss and welcome to SGL.  

Sorry to read about your mishap. You could try a few things...

• Not sure whether the you have misaligned the focusser/drawtube. Even if slightly out of alignment, it will cause focus issues now or later and may/will require a replacement part or parts. 
• Can you focus the OTA and e/p without the diagonal in place? - (note: some 'scopes the diagonal makes up part of focal length) - if you can focus without it, than you may have misaligned the diagonal. If it can focus, then buy another diagonal, (see sellers/vendors T&C's regarding returns before purchase). A replacement, (not neccessarly the same type or of the same brand; but as long as it is 1.25"), it maybe better than the original.
• Are you a member of a local astronomy society/club? or is there one nearby to you? - If "Yes!" ask and see if you can borrow one; even if it means taking along your 'scope to try it; assuming you can get out and about and the society/club is 'open' due the current COVID-19 lockdown/curfew restrictions. 
• As a last resort; you could contact the seller/vendor for a one-to-one replacement; assuming there is no physical or visible damage and you have all the original packaging. If it was delivered via postal service or courier; then you may or may not be responsible for the costs of returning it.

[ronl]

Hello Dave and welcome to SGL, sounds like you have damaged the diagonal, you should replace it with a

new one, they are not that expensive. Good luck.

[Louis D]

As @ronl suggests, the diagonal might be damaged.  It's easy enough to verify by putting an eyepiece directly in the focuser draw tube and looking straight through.  You'll need about an extra 60mm of out-focus (extension) to reach focus without it in the optical path, so you may end up having the hand hold the eyepiece behind the fully extended draw tube to reach focus.

[DaveMoss]

Hi all, thanks for the welcome and for your posts - REALLY helpful. I tried as @Louis D suggested and after getting a slightly sore neck it does seem to focus when I fully extend the focus draw and hold the eye piece around 6cm away from the entrance. So it sounds like I need a new diagonal piece - I’ll have a search online. 
 

Thanks for getting back to me so quickly I really appreciate it - hopefully the replacement part works, I will keep you posted!