The importance of collimation

[paulhutch]

Just a quick note to let all the newbies like myself how much difference collimation of your new scope makes. I bought a Next generation laser collimator last weekend and managed to work out how to use it (quite easy really). Me and her indoors (reluctantly) set about twisting and turning the mirror knobs and within an hour it changed the view of Jupiter from good to outstanding. We currently have a 300p dob and keep moving it from the front room to the garden, all this shifting and knocking must have slightly moved the mirrors out of line. So have a read of your manual and the section regarding collimation, it can be done inexpensively and is well worth doing.

[barkis]

Absolutely Paul. And good advice.

It can't be stressed enough how important it is to ensure the Newts. and Compound Scope, are perfectly collimated.

Ron.

[Si W]

Accurate Collimation, Very important indeed....

[JimStan]

Learn how to do the collimation on real star images. That is THE most accurate way to achieve the results you desire.

Actually, you can use the sun's image reflecting off any shiny, curved surface to create an "artificial star", and get results that are very close to ideal. Just DON'T aim the scope directly at the SUN itself ! I have been successful in seeing the Sun's reflection in garden chrome ball decorations, bumpers of automobiles, etc. and using them to line up the mirrors.

Some laser collimators are inaccurately aimed, and will throw your results way off! Just a word to the wise.

Jim S.

[Shibby]

Jim, that sounds like potentially dangerous advice - I would avoid using the sun in any way, curved surfaces vary.

But you've reminded me to check my collimation Paul It's been a while since I have!

[paulhutch]

Thanks Jim but I'll stick with the laser for now, it seems to have worked brilliantly. I couldn't believe how clear one of Jupiter's moons were, not only the satellite itself but the shadow it cast upon Jupiter once collimated. An amazing difference.

[JimStan]

Quite safe as long as it is something like a shiny ball, or curved part of a bumper, etc. When our club does daytime outreach events with solar filter equipped scopes, we ALWAYS make sure that the public understands that they must NOT by any means, look directly at the Sun. I am very aware of what is safe to look at, and what is NOT! However, if there is any uncertainty about it, it certainly is safest to NOT try it !

Point well taken.

Jim S

[ismangil]

I've seen the advice of Christmas decorations ball as well in collimating the Astromedia paper reflector.

It mentioned that it is safe because the reflection is really small.

What is the recommended distance of such artificial star?

Perry Ismangil

[Luke]

Good point, Paul, I wish I had learnt it sooner. I spent months avoiding high power eyepieces on my dob when all it needed was a few minutes of collimation to get the high mag sharp again

[Si W]

using a ccd is my preferred method to tweek my scope, i just get a nice donut on the screen and take it from there, works a treat.

[paulhutch]

Good point, Paul, I wish I had learnt it sooner. I spent months avoiding high power eyepieces on my dob when all it needed was a few minutes of collimation to get the high mag sharp again

I would like to say it was a few minutes but alas it was over an hour.....On the bright side I now know German as that is the language the instructions were in.

[JimStan]

I've seen the advice of Christmas decorations ball as well in collimating the Astromedia paper reflector.

It mentioned that it is safe because the reflection is really small.

What is the recommended distance of such artificial star?

Perry Ismangil

That works very well, Perry, and I have made an "artificial star" using a ball bearing ! As far as the distance to such an artificial star, you must be able to focus the scope on the point of light. That point of light is going to mimmic a star, as it is very tiny, but of course, the surface of the ball is at a certain distance from the scope, and the scope must be able to reach focus at that distance. It is a tradeoff between the perceived size of the ball, and the actual distance, but as long as you can focus on it, you will be OK. Most scopes I have played with will focus down to around 250 feet or so. That is about the equivilent of two suburban lots.

Jim S.

[swamp thing]

Hi Paul

In my experience larger mirrors ( over 10") should be collimated every time the scope is moved from one place to another.

The larger and heavier the mirror the more chance it will move out of alignment.

small lighter mirrors do not seem to need the same amount of attention. Although it is always a good idea to check collimation anyway.

It only takes a minute or two.

Regards Steve

[ItIsOnlyMe]

I too have just saved up the pennies for a Baader Laser Colli and first night out after that was the first night I saw the GRS on Jupiter. Amazing!! Had looked about 20-30 times previously and either I was very unlucky and it was the "back"of the planet or collimation really does make a difference. Now I am collimating each time I use the scope as it is also a 300P. Its a piece of cake to do once you get over the fear of breaking it or making it worse.