any point ? Bahtinov mask that is !

[blacksaltire]

Hi folks, have been reading about these mask thingies

and was wondering if one would help my situation ? Got a skywatcher 150 6" refractor, hoping to do some "not so serious" imaging with my canon eos 300d so far dashed problems ! firstly with the sloppy focusor on the scope, (thanks to glider from these forums for the ptfe tape. now sorted !) Secondly due to no live-view available for the 300D and my **** eyesight:icon_eek: still focussing probs. Lots of trial and error i understand ! But can anyone advise on whether one of these Bahtinov dudes would work for me and if so how so ? Thanks a lot peeps:icon_scratch:

ps the mount is manual if that helps ! ta !

[ollypenrice]

These masks are excellent. When in focus they give an image of a bright star with three cat's whiskers coming from each side. When in focus the central pair of whiskers make a straight line through the star. When not in focus this straight line appears either above or below the centre of the star so you adjust the focus accordingly.

However, without a Live View, what will you do? Hmmm. I don't know if the Bahtinov Whiskers will show in the viewfinder. I seem to think that they do on bright stars but I'm not sure. Someone else will know. Otherwise you would just have to click off and discard a succession of images of the whiskers getting better or worse, I imagine.

Olly

[blacksaltire]

I think i understand now:icon_scratch: maybe lol ! Question is do they work with refractors ?? it seems to me that any body who talks about Bahtinov masks has a SCT or DOB or REFLECTOR !! aarrgh tres confusing mon amie !lol! excuse the french i can barely speak english (Ecosse oui ! haha ) I now understand the principal behind them though Merci !

[ncjunk]

Yes, is the answer. With my nikon and a refractor, i would put the mask the refractor take a photo and then view it on the pc. Change the focus, if it is incorrect, and repeat.

[Psychobilly]

Even though my camera have liveview I prefer to take 6s shots at high ISO using the supplied EOS_Utils and review the image on the PC I then use the Bahtinov Grabber app to analys the image and give a precise indication of focus...

I only use live view as a last resort if the camera isn't tethered to a PC... Used for any length of time liveview heats the Sensor causing "glow" artefacts and increased noise...

Peter...

[adamsp123]

Here is a pic when using a mask as is in focus, it is very sensitive method a slight tweak of the focuser will move that middle line very clearly.

[blacksaltire]

wicked guys thanks ! looks like it's bloo peetah time again woohoo !

(wife hates those days!) haha ! thanks again to all,,.,.,.,

[Tim]

yep, three words sum it up:

Get one now

I wouldnt be without mine

[Euan]

A Bahtinov Mask will change your life*

*a slight exaggeration but they extremely useful

[gary1968]

They really take the guess work out of focusing, I have 3 now, 1 each for my zs66, c80 and 8" newt.

As the others have said, get one, they are the dogs doodahs......

Gary

[simon955]

I have seen home made masks on some scopes, does anyone know where you could download patterns?

Have laser cutter at work and i fancy making some, possibly to give away to my AS members.

[Psychobilly]

I have seen home made masks on some scopes, does anyone know where you could download patterns?

Have laser cutter at work and i fancy making some, possibly to give away to my AS members.

Here you go Simon there are quite a few "generators" on the net... Google should throw up a few more for you...

astrojargon - Bahtinov Focusing Mask Generator: Overview

Peter...

[adamsp123]

This is the site I use for all of mine that I have made

http://focus-mask.com/Free_Templates.html

[r3i]

If, like me, you're not that skilled with a cutting knife or if, like me also, you don't have the patience, then good quality masks can be purchased from Bahtinov Focusing Mask and Bahtinov Mask Specialists | Stay Focused I bought one for my SCT and one for my short tube refractor and like everyone else has said, they are superb.

[rawhead]

Stay Focused also appear to be on ebay

Bahtinov mask 80mm to 110mm telescope refractor on eBay (end time 15-Jul-10 11:17:09 BST)

bit cheaper i think...

[simon955]

Thanks for the links guys, will try one out on the machine.

[Shibby]

I have one made out of paper, held on with a hairband Can't see any interference pattern through the camera so I have to take 8s exposures (*after* aligning mount/scope) to see the pattern, tweak, take another, tweak, etc, etc...

[TheThing]

I've got an AstroTak version and it is superb! I had trouble seeing the spikes clearly on a laptop screen with a webcam, so I used a parfocal EP visually to get it right and then put the webcam in. Works a treat!