Regretting Purchase of new telescope

[pevsfreedom]

I take it the adjustment screws on the finder should be relatively cranked down? They were pretty loose before, I figured it was normal since they are ADJUSTMENT screws, I'll have a look tomorrow and see if they are aligned at all now that I've cranked them, maybe that's the problem.

[kens]

The silver "locking" screw is spring loaded and keeps everything reasonably snug. Makes it much easier to adjust than having three screws to fiddle with. The two adjustments screws should each have a locking nut on them. Once you get aligned then set the lock nuts so the adjustments screws cannot move.

[alfingido]

Just looked at a picture of your scope, the finder has its own mount near the focuser, so it shouldn't move. Generally, the finder is held in place by the rubber ring at one end and by three adjusting screws. One is normally spring loaded and the other two are used for adjustment. The finder should be firmly held in place by all three screws, if its flopping about, they must be loose and this is why you are losing alignment.

Observing on a windy day is a nightmare, the tube will vibrate and move. If its windy outside, I stay inside.

I can't understand why you are squinting to see through the eyepiece. You need to be in a dark place with no immediate lighting, and allow your eyes 10-20 minutes to adapt properly. Either the image is too bright or it is out of focus. Jupiter is pretty bright anyway, but even through my 8" sct, I don't squint to see it.

It all points ( in my opinion) to bad collimation. I remember a 6" newtonian I had many years ago that was badly collimated and I had to squint to try to focus anything. I never knew about collimation and gave it away to a local school group, who collimated it and were very happy with it!

I think you need to read up on collimation and make sure it is as it should be. You shouldn't need to squint to see anything.

Allan

[pevsfreedom]

No lock nuts, just thumb screws that are wobbly unless cranked. 

[pevsfreedom]

Just looked at a picture of your scope, the finder has its own mount near the focuser, so it shouldn't move. Generally, the finder is held in place by the rubber ring at one end and by three adjusting screws. One is normally spring loaded and the other two are used for adjustment. The finder should be firmly held in place by all three screws, if its flopping about, they must be loose and this is why you are losing alignment.

Observing on a windy day is a nightmare, the tube will vibrate and move. If its windy outside, I stay inside.

I can't understand why you are squinting to see through the eyepiece. You need to be in a dark place with no immediate lighting, and allow your eyes 10-20 minutes to adapt properly. Either the image is too bright or it is out of focus. Jupiter is pretty bright anyway, but even through my 8" sct, I don't squint to see it.

It all points ( in my opinion) to bad collimation. I remember a 6" newtonian I had many years ago that was badly collimated and I had to squint to try to focus anything. I never knew about collimation and gave it away to a local school group, who collimated it and were very happy with it!

I think you need to read up on collimation and make sure it is as it should be. You shouldn't need to squint to see anything.

Allan

I'll review it again tomorrow, pretty sure I had it spot on. Did it initially indoors and took it outside and checked with laser and it seemed good. May have overlooked something. Definitely won't go out with wind again... it was VERY, VERY windy, maybe that was my main problem. It's definitely flopping around, but the screws were loose like I mentioned, will try again with them tighter. I was definitely squinting. 

[alfingido]

No lock nuts, just thumb screws that are wobbly unless cranked. 

They need to be tight against the finder body

[happy-kat]

I'll review it again tomorrow, pretty sure I had it spot on. Did it initially indoors and took it outside and checked with laser and it seemed good.

If the laser is out then you will have problems.

Do a star colimation test, don't use the laser.

[pevsfreedom]

They need to be tight against the finder body

Very well might be the problem, I'll try it again tomorrow. I suppose they wanna be fairly tight? (the screws themselves). For some reason I thought them being loose would be ok since they're 'adjustment screws' so that was dumb on my behalf.

If the laser is out then you will have problems.

Do a star colimation test, don't use the laser.

Any simple explanation of how a star collimation test goes? I'll look it up otherwise, thanks. I noticed stars (like Rigel) looked pretty good, despite everything else. I think this finder scope fix will help me a lot.

[happy-kat]

There is an excellent star test sheet showing in and out of focus stars and what the various distortions mean

http://www.telescope-optics.net/diffraction_pattern_and_aberrations.htm

[alfingido]

This might help, although there are many articles online about how to do this.

http://astronomy.stackexchange.com/questions/150/how-can-i-collimate-a-dobsonian-telescope-with-a-laser-collimator

Good luck!

Allan

[pevsfreedom]

I have a stupid question. Everything I see about laser collimation says don't look at laser. How do you use the laser if you don't look at it? How can you see it in the center circle on primary without looking? Mines very dim however so it's not bad at all. 

[pevsfreedom]

And thanks for help and links everyone

[Space Beagle]

Astro Baby (a well respected member on SGL) has done a really good collimation guide, which works for me! Here's a link - good website too!

http://www.astro-baby.com/collimation/astro%20babys%20collimation%20guide.htm

Hope you get sorted soon as that looks like a nice scope!

Regards,

Doc

[pevsfreedom]

Astro Baby (a well respected member on SGL) has done a really good collimation guide, which works for me! Here's a link - good website too!

http://www.astro-baby.com/collimation/astro%20babys%20collimation%20guide.htm

Hope you get sorted soon as that looks like a nice scope!

Regards,

Doc

Thanks, looks very detailed. 

[pevsfreedom]

As far as the scope itself how long before I start observing should I bring it outside? 30 minutes to warm-up/cool-down? Thanks

[pevsfreedom]

I've also noticed laser collimators generally seem frowned upon. Same was stated in that guide that was posted. Would I be better off just selling this laser one and getting a cheshire collimator? Thanks. 

[bogdog]

you should maybe ask a friend to help you out?

by that i mean you get somebody to confirm that they see exactly what you see,if you set it all up and focused ask them if they see it the same

if they see it all blurry ask them to turn focuser gently to bring it close so it is normal for them,then you look

it would then confirm if its you or the scope

dont let the frustration of it beat you to the point you give up

hope you get sorted out

[happy-kat]

I have a smaller telescope but I just use my lowest powered EP 32mm for the first 30 minutes or so.

[NGC 1502]

Hi there. You have a lot of good advice, Ill just add, how about contacting / visiting a local astronomy club for help ?

Of course, I can't guarantee how helpful they may be, but in the UK the majority go out of their way to give advice.

Hope you make progress, it's definitely worth the effort, Ed.

[leelee970]

You can check your laser is correctly collimated by making a very simple V block.

 

You need a piece of flat wood and 4 long nails. Hammer the first two nails into one end of the wood to make an X, and then hammer the other two nails a little distance along the wood to make a second X.

 

You need the distance between both sets of X's to be shorter than the length of your laser.

 

Place this rig some distance from a white wall (the further away the better, but 20ft will do).

 

Place your laser in the rig and switch it on. You should have a laser dot on the wall. Now carefully and gently rotate the laser and watch the dot. (Make sure rig doesn't move, only laser).

 

Your laser dot should remain in the same spot. If it moves in an arc then it is out of alignment and so using it on you scope would be useless.

 

You can adjust the laser but it can be more hassle than it is worth.

 

At least by checking your laser you will know if it is out of alignment.

Lee

[Cath]

If a pair of binoculars lets you experience what a telescope doesn't, then ..

[gbarnett]

Hi,

stick with it.

You've only had a few sessions so it's very early days yet. You'll get there.

If you bought a cheap laser and it's not working out it will still be useful for the barlow laser method ... if you get a barlow at a later date that is!

Graham.

[daz]

When people say don't look at the laser - what they mean is don't stare directly at the beam. In other words, don't shine it in your eye!

It's fine if it's a glancing view as you are going through the collimation process, but don't deliberately stare at the beam....

[gnomus]

Yeah there's a rubber oring. It still flops about though.

I wonder if this might be the key (to the finderscope issue anyway).  The finderscope should not "flop" about.  It should be held in place by the spring-loaded pin and by the two adjustment screws.  You need to tighten the adjustment screws so that they are snug against the tube of the finderscope.  They don't need to be uber-tight, though.  After that you align the finderscope by making small adjustments to these screws.  You may find that you have to slacken off one screw to adjust the other.  Everything should be fairly snug though.  The finderscope flopping about is definitely not normal.  If the finder still flops about when everything has been tightened up, I suppose that the only other thing that it could be is the spring-loaded pin becoming "un-spring-loaded" in some way.

[Dave Lloyd]

I have a stupid question. Everything I see about laser collimation says don't look at laser. How do you use the laser if you don't look at it? How can you see it in the center circle on primary without looking? Mines very dim however so it's not bad at all.

That's not a stupid question.