Is my collimation out?

[WestAusChris]

Hi again all

I took the bino's out to have a look at venus tonight and when i looked at it it appeared to be a bright dot with no sharp points coming off it which im guessing is a good thing but noticed just below it what looks similar to a nebula which i know it isnt.

Hard to explain really but if i closed my right eye and looked through the left lens on the bino's i see the bright dot of venus, then i close my left eye and look through the right side of the bino's and the bright dot is gone replaced by the shape of venus but looks more like a nebula.

If anything it looks similar to the crab nebula but ofcourse tiny and far less detail.

Being new to astronomy (other than looking with my naked eye) im a little confused as to this, am i using the bino's wrong or is the collimation out or have i just bought a crap pair lol.

P.S After doing a bit of reasearch, if they werent collimated right i would of thought id get two images of venus looking exactly the same not 1 image being clear and the other looking like a big blury nebula, im wondering if maybe one of the lens is out of wack and not the prisms but again im new so im just guessing

[noswonky]

Did you focus the two eyes separately? It sounds like the right ocular is just out of focus.

[WestAusChris]

Hi Peter

I did or atleast thought i did focus both eyes separately but when i try adjusting the diopter adjuster the image does seem to merge more into one image although turning it one way they will start to come together but then i run out of adjustment and they wont turn any further.

I have a feeling im just going to have to pick the brightest star and keep fiddling until i get it right, try try try again :)

[erick]

Do more testing during daytime, Chris. Easier then to see if there is a focus problem or collimation problem. Tougher to deal with these matters using the night sky.

[WestAusChris]

Well i tried as you said Eric to do some tests during the day.

Put lens cap on the right lens focused using my left eye turning the centre focus wheel got it in focus (or atleast a half decent image) , put lens cap over left lens and used the diopter ring and tried focusing with my right eye.

One problem the diopter forcus ring wont turn any further clockwise to achive any better focus, the image when i get a semi decent focus seems cloudy/milky aswell.

tried focusing on a roof of a house and im sure i can see two images aswell which leads me to think that collimation is out aswell.

Should of saved my $229 and bought a kiddies telescope im sure id get better images in them than these Bino's!!!

Im very tempted to email the website i bought them from and tell them they just dont work and want a refund :(

[erick]

Doesn't sound good, the adjustment should cover a good range of variation in eyes. But here are a few ideas:- Do you wear glasses for distance? Try it again with glasses on. Have someone else who has different eyesight try it.

$229 should have got a respectable pair of binoculars. Australia website? Might be easy to get them to respond and swap for another pair. Overseas website - maybe harder to achieve.

[WestAusChris]

Dont wear glasses, as far as i know i have good eye sight.

Took them over for my father to try and he does wear glasses but seems to think he cant even get both images to merge into one and cant seem to get a half decent focus.

I tried them again today during the day and i seem to get them to merge into one image at a tree and get them in focus but hen i still look at venus i seem to see one pin point star and another below it that seems out of focus.

very frustrating :)

Just wish AOE was open would of bought from them first :(

[erick]

Running out of things we can do via message exchange, unfortunately. It's a matter of step by step checking each "element" in the system - left barrel, right barrel, focus of each, then both together, focus of both together then followed by collimation. The Zoom control throws an extra curved ball into the system. Where are you Chris - close to Perth or not?

I should have said that "glasses" was really about checking focus. If the naked eye needed a lot of adjustment, beyond the range, it is likely the glasses-corrected eye required less.

[WestAusChris]

Hi Eric

Im actually south of Perth in a sleepy town called Bridgetown.

Id say id email Saxon and ask where they hide their collimation screws but im not even sure how to adjust, i have a feeling moving the right screw clockwise moves the image down and to the left but i would research that before hand or i could make them even worse.

I will try tonight as we have clear skys here to see how they go then one more try tomorrow during the day and if all else fails will do as you said and see if they can send me another pair.

[erick]

Yep, try for a replacement pair. I suggest you don't go adjusting the prism tilt screws until you are very certain that both barrels are focusing fairly well and that there really is a need for collimation adjustment. From what you have described, I'm still unsure about that. Sorry mate, if you lived down the road we'd have it sorted.

That's why I asked about Perth. You could walk into one of the few shops there and see if someone who knew binoculars could have a quick look.

[WestAusChris]

Well some good news, looked at venus again and it seem to be 1 image, not sure what i did but everything seemed quite clear.

Do find it hard to get a good focus as i move around the night sky though but what i need to do is either build a better mount or buy a better tripod as this cheaper one moves around alot.

Will have another look tomorrow night and see how i go :)

Thanks for all the advice will keep yu posted on how things progress