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Jen
09-07-2008, 05:46 PM
Hello everyone :hi::hi::hi::hi::hi::hi:
I am not happy with the way my barlow lens works :mad2::sadeyes::(:(
When i focus in or out it also moves up and down :screwy:
Should it do this? :shrug:
Is this normal or is it a common problem with these or is there a way to fix this i cant seem to see any screws around this that i could tighten any more to fix this problem
And its really annoying :doh:
:help::help::help::help:

Kevnool
09-07-2008, 06:09 PM
It should move up and down cause its connected to the focuser and the eyepiece ...but on the otherhand if you cant focus with it in there pull it out 1/4 inch and lock it in again ..thats what happens when i use my barlow.....cheers...Kev.

Ric
09-07-2008, 06:27 PM
Hi Jen, Kev is right the barlow sometimes needs readjusting in the focus plane to get the best and sharpest focus.

Also if the seeing or atmospheric conditions on the night are not good then then the barlow can be rendered almost useless at high magnifications.

Cheers

erick
09-07-2008, 10:09 PM
In and out - OK understand that. Up and down? Nope don't understand - can you explain further? What is the "it" that moves up and down? :confuse3:

OK checklist since you have tried some novel approaches before :D. You have put the barlow into the empty focuser (what barlow is it? is it a 2 times? Is it 1.25" diameter or 2" diameter) Then you have put the eyepiece into the barlow? Which eyepieces have you tried?

Glenhuon
09-07-2008, 10:53 PM
I think you have the standard Skywatcher rack and pinion focuser Jen. Correct?
Sounds like there is up/down movement in it like mine was.
Its not really noticable with just an eyepiece, but when you put the barlow in and eyepiece on top it becomes a nuisance especially if you are focusing with the focus tube a fair bit out.
You might have to fit an extender before the barlow so the outward travel is not so great. Either that or fit a Crayford and extension like I did.
The other suggestion of having the eyepiece/barlow out about a centimetre or so would help too.

Bill

Kevnool
10-07-2008, 06:21 PM
Sorry for being dumb who needs ejumacation:sad:

Kevnool
10-07-2008, 06:36 PM
Lets try this Eric :P

The focuser being either the the standard model or the 10:1 model in which case the tiny gearing mechanism spins ten revolutions to one revolution to get movement in and out fast or slow.

Then the barlow is inserted to this focuser then the eyepiece is inserted into the barlow and then the whole shebang moves in unison ( in & out)

But remember Jen i tried to help you in a simple way .....:hi: cheers Kev.

Jen
11-07-2008, 04:54 PM
:lol::lol: Ok let me explain it a little better hahahah :screwy: :doh:well i will try
The steel piece that moves in and out of the barlow well when i first go to focus on something it will move up and down first its like its like it has a movement there that shouldnt be because it does make it hard to focus does this make any sense now lol sorry Eric :screwy:
Um i wouldnt have a clue what brand the barlow is it came stock standard with my scope a 2x barlow is all i know :help: Oh and the eyepieces i use are a 25mm and a 10mm

Jen
11-07-2008, 04:57 PM
Hey Bill yes that sounds about right so it is a common thing for these then? :mad2: Dam it oh well good excuse to update already then LMAO :D:P:thumbsup:

Jen
11-07-2008, 05:02 PM
:hi::hi::hi:
Thank you so much Kev the next time i get a nice nite i will try and do that if it annoys me too much i will just get a new one :P:D I only have to try and focus in just the slightest touch and it will go up or down depends which way im going grrrrrrrrrrrrrrrrrr before it focuses in and out :screwy::screwy:
:thanks:

Kevnool
11-07-2008, 05:51 PM
Whats that Jen, until you get a nice night , it should be the same here ( cloudless ) 441 klm,s is not that far away......:driving:.cheers Kev.

Glenhuon
12-07-2008, 12:36 AM
There is one thing you could try Jen. On the underside of the focuser you'll see 4 small screws that hold the pinion shaft in place. Tighten them equally about a turn or so, but not so tight it makes it hard to move the focus tube. Under the plate that they hold on is a spring that pushes on the pinion shaft and presses the inner tube against the inside top of the focuser housing. It has a strip of nylon inside, so wont go metal to metal. Should help to take up some of the movement.

Cheers
Bill

Jen
12-07-2008, 07:01 PM
Hey there Kev i know 441km away dosnt sound like much but dam we have had clouds here 4 two weeks now :sadeyes::tasdevil::tasdevil::tasde vil::tasdevil::tasdevil:



:thumbsup: Cool thanks Bill i can see the small screws there if only i can find something small enough to use on them :screwy: i wi:Dll have to raid hubbys shed tonight :lol:
:thanks:

Globular3
12-07-2008, 07:04 PM
Hello Jen,

This up and down movement is something that I've seen to happen as the rack and pinion focuser reaches either end of its travel. I'd try moving the focus knob in or out slightly to avoid this. If you can't get a clear image, then try doing what the others suggested by moving the eyepiece out of the barlow slightly. Just make sure that the thumb screws are tight to avoid the lens falling out.

Hope this works for you.

Regards,

Glob.

Jen
12-07-2008, 07:15 PM
Thanks Glob it seems to move up and down no matter where it is along its travels i have two things to try out so i will see how I go :)


Thanks for all the help once again guys :thumbsup:
i just hope this works cheers ;)

Kevnool
13-07-2008, 05:21 PM
Was just wondering :confuse3: Jen did you get a 3x barlow with your scope when you brought it ?

Jen
13-07-2008, 11:30 PM
No it only came with a 2xbarlow :screwy: