Telescope Focus

[Renau]

Hi everyone, Renau here! I would try to explain my problem the best I can in my bad English, so be with me please.

I am new to this hobby and I have a poor eye site, so my question is regarding the focus mechanism on the telescope I have at the moment, when I try to focus at an object, when I turn the wheels on the focus bit, I only have a very very little moviment to try to get the object in focus and most of the time I can't get it right, so my question is, can I change the mechanism on the telescope for a better one that can give me more scope to focus the object, or I can't and the eye pieces can help or not?

Sorry if you have this questons a million times before, but I would like some help on this please, cheers

[damnut]

Hi Renau,

Stunning location you are at!  And near a great golf course... You can buy a dual speed focuser, but these are expensive. Its usually a case of practice, and spending time with the scope. Please can you post details of which telescope you have.

If it is not the focuser the the telescopes optics may be out of alignment. Do try and achieve focus during daylight but try and use an object that is at least a few hundred metres away.

[Dr_Ju_ju]

Although its difficult to see from the photograph, the focuser has a small knurled screw under the 2 focuser wheels, which applies tension to the focuser tube, this may need to be released to ensure that you have full travel of the tube.

[ronin]

Cannot work out what the scope is.

Few things come to mind, how well collimated the scope is as that may be causing the image to lose sharpness, which can translate as not too good on focus.

What are the eyepieces and and which are you using, the higher power one(s) if supplied with the scope are often not great and again can give a poor image.

Finally if the focuser is a single speed then it can be difficult to get it "just right".

That is sort of 3 possible things and it may be one or more.

[Renau]

Hi Renau,

Stunning location you are at!  And near a great golf course... You can buy a dual speed focuser, but these are expensive. Its usually a case of practice, and spending time with the scope. Please can you post details of which telescope you have.

If it is not the focuser the the telescopes optics may be out of alignment. Do try and achieve focus during daylight but try and use an object that is at least a few hundred metres away.

Hi, the telscope I have now is a aspen 1000x130 reflector, how much you are talking about, thanks

[Renau]

Although its difficult to see from the photograph, the focuser has a small knurled screw under the 2 focuser wheels, which applies tension to the focuser tube, this may need to be released to ensure that you have full travel of the tube.

Hi Julian: I check and this one not have a screw underthe mechanism, thanks

[Renau]

Cannot work out what the scope is.

Few things come to mind, how well collimated the scope is as that may be causing the image to lose sharpness, which can translate as not too good on focus.

What are the eyepieces and and which are you using, the higher power one(s) if supplied with the scope are often not great and again can give a poor image.

Finally if the focuser is a single speed then it can be difficult to get it "just right".

That is sort of 3 possible things and it may be one or more.

Hi , the telscope I have now is a Aspen 1000x130 reflector

[damnut]

Hi Renau,

The start cost is c£100, but I have not found one suitable for your scope. :-- http://www.widescreen-centre.co.uk/Products/Dual_Speed_2_Inch_Crayford__.html

Your scope is too narrow for this model.

Do try to spend some time at the scope as it may just be a case of practice.

[Renau]

Hi Renau,

The start cost is c£100, but I have not found one suitable for your scope. :-- http://www.widescreen-centre.co.uk/Products/Dual_Speed_2_Inch_Crayford__.html

Your scope is too narrow for this model.

Do try to spend some time at the scope as it may just be a case of practice.

Thanks Damian, I will and I will check the link, cheers

[damnut]

Hi Renau,

The dual speed on the link will fit down to 150mm and yours is 130mm. But will give you an idea, if I find something suitable I'll post in this thread.

[jonnymac]

Im not sure what type of focuser your telescope has but the youtube link below might be useful, it wouldn't do any harm to take it apart and give it a clean and inspect it for any issues  though I would think it is more related to your collimation.  I would try and identify where the issue is before buying any new equipment.  As damnut said, get your telescope out during the day and point it at something at least 0.5km away, you should be able to achieve a crisp focus, try more than one eyepiece and check your collimation.

 https://www.youtube.com/watch?v=ofOSAMlqZWw

[Cornelius Varley]

Google "diy telescope electric focuser" for some ideas for a motorised focuser. The Skywatcher autofocuser might also be adaptable for your telescope. Another option might be to change one of the focuser wheels to one of a larger diameter (larger sponge rubber wheel stuck over the existing) . This problem has been discussed before on the forum so you might be able to find a solution after searching here.