Collimation Tools. Do You Really Need Them?

[Mav359]

I'm quite comfortable with collimating my SCT, turn of a screw here, recenter there but I'm always left wondering if it could be better. Its all well and good me looking at the star and saying "Yes they are as concentric as they are going to get" but someone else may think it can still be improved.

For imaging does 'near as dammit' cover it? is that good enough? I look around at the differences between collimator's and everyone seems to have a difference of opinion about how good or bad they are, so, are they any more accurate then my own eyesight?

The new ho-tech collimator on FLO website seems to be a very accurate system but at £390 it needs to be, is it or any other collimator truly 100% accurate and therefore do i stick to the star/eyeball method or is it worth investing some money & if so on what?

Cheers

[DirkSteele]

I will leave it to others to offer opinions on whether £390 is money well spent for excellent collimation. However, this solution is close to free (scissors, cardboard and some patience) and achieves very good results. It is called a Duncan Mask.

http://www.astrovox.gr/forum/download.php?id=17658&sid=646453d99bbd6eef6845f3d3254b6ff9

Clear skies,

[Mav359]

Deffo giving this a try, can't believe i haven't seen this before

[Mav359]

Matthew is there an easy ay to re-size the print out to fit a 9.25" scope?

[DirkSteele]

I scaled it up for my C11 scope by hand. Perhaps blowing up the image using a photocopier?

[Freddie]

MetaGuide and a high fps cam is the way to go for me. It's a free download.

[perfrej]

Defocused star and concentrtic rings - that's you basic measure. Next, add CCD Inspector and let it measure an image. It will tell you how well collimated you are.

/per

[Digz]

I am by no means an expert in this but my understanding would be for imaging, collimation is critical. It also becomes more critical, and harder to achieve, the faster the scope is.

As for the tool, I couldn't say what is best, people use cheshires, sight tubes, lasers, star tests etc etc.....

[Mav359]

i mocked up this Duncan mask using a bit of cardboard and tried to have a go before the cloud that wasn't suppossed to be there rolled in. I'm well impressed it so simple to use, gives you a reference for the screws to turn. didnt really get a chance to finish but i was impressed enough to order a sheet of perspex to create a permanent mask. i'm also going to mock one up in carboard in the style of my bant mask which just hangs of the end of the scope.

Great shout Matthew

[DirkSteele]

You are more than welcome.

Clear skies

[alan potts]

Depends on the scope, My SCT RC and Mac Newt are all colimateable with a star and a bit of messing about with an allun key. So in my case no it is not necessary to have fancy gear, but nice if you have nothing else to spend money on.

For Dobs and Newtonains the colimation is much more difficult without aids, so for these I would say they are needed.

Alan.