Collimation

[Anthony1979]

Thank you for all your assistance.... When i looked at a bright star through it it had spickes coming from it

[Alan64]

On 29/04/2019 at 14:45, Anthony1979 said:

Thank you for all your assistance.... When i looked at a bright star through it it had spickes coming from it

Yes, that's due to the lovely spider-vanes supporting the secondary-mirror, just inside the front of the telescope...

It is possible to minimise, perhaps to even eliminate the effect, and with a single curved vane...

https://garyseronik.com/how-to-build-a-curved-vane-secondary-mirror-holder/

With my own 150mm f/5, it's particularly annoying when observing Jupiter, or Mars during its last opposition, but a variable-polariser works a treat in those instances, and perhaps for the brighter stars as well...

https://www.365astronomy.com/variable-polarising-filter-1.25-by-ovl.html

The object will be dimmer, of course.  In the case of Jupiter I was finally able to see the planet's features with the filter integrated.

 

[Anthony1979]

Thanks.... And little ticks coming of them... Its weird

[Alan64]

23 hours ago, Anthony1979 said:

Thanks.... And little ticks coming of them... Its weird

Ah, those may due to ghosts and glares, those in turn caused by reflections along the light path, whether within the eyepieces, a barlow if applicable, or the telescope itself. 

Have you ever heard of blackening and flocking the interior of a telescope?

[johninderby]

Use this

https://www.firstlightoptics.com/misc/black-velour-telescope-flocking-material.html

 

Edited May 3, 2019 by johninderby

[Anthony1979]

Never heard of it thanks

[Anthony1979]

Wouldn't this mean i would need to take the spider part off

[Alan64]

On 02/05/2019 at 19:55, Anthony1979 said:

Wouldn't this mean i would need to take the spider part off

Actually, you'd need to take the Newtonian completely apart, for a proper job.  Ah, but no more ghosts and goblins within the field-of-view.  When observing an object, the contrast would be noticeably improved, to see its details more clearly, and the background sky surrounding the object would be blacker, instead of just grey-black.  Have a look at what I did to my own...

https://stargazerslounge.com/topic/262096-deadening-a-150mm-f5-newtonian/

Any questions?  I'd be glad to help.

[Anthony1979]

Wow... I think i would need a lot more experience before i do anything like that plus the scope is new so i dont really want to be messing around with it 

[Alan64]

11 hours ago, Anthony1979 said:

Wow... I think i would need a lot more experience before i do anything like that plus the scope is new so i dont really want to be messing around with it 

Quite right, as you want to have experience with the telescope and its workings beforehand.  It was a year of observing before I began my own.  You would be without the telescope during the renovation, of course, but then you'd have the improved views of which to look forward once it's completed.  In addition to the flocking, I use matte, chalkboard-black spray paint, and I sometimes spray the paint into a condiment lid or other and apply the paint with artists' brushes, when applicable.

Within my link posted previously, I later abandoned the idea of flocking the drawtube of the focusser.  Its interior might need to be repainted however, if desired, and upon inspection.  The "black" paints used by the manufacturers are nowhere near the blackest available.

The goal is to make the front entry and the entire interior of the telescope up to the eyepiece as inhospitable to stray reflections of light as possible.

If I had to go back in time, and before my own was performed, I wouldn't observe with it until after I did it all over again.

[Ledge1962]

It is natural to be nervous of new equipment. Honestly, when I bought the 14", I got stressed trying to figure out what I could touch and how bad the views would be if I didn't collimate it. The views were fine and with the assistance of the good people of this forum, I now have added a Kendrick heater to the secondary mirror, I collimate the scope with ease and have even gone so far as getting an autocollimator.

Give yourself some time and read Astrobaby's guide a few times and you will become proficient at tuning. I personally (others may have a different view) would not suggest getting the autocollimator until you understand the basics of the mechanics of the scope and a bit more experience, as the instructions alone will give you nightmares. 

[Anthony1979]

Thank you 

[JG777]

13 hours ago, Ledge1962 said:

It is natural to be nervous of new equipment. Honestly, when I bought the 14", I got stressed trying to figure out what I could touch and how bad the views would be if I didn't collimate it. The views were fine and with the assistance of the good people of this forum, I now have added a Kendrick heater to the secondary mirror, I collimate the scope with ease and have even gone so far as getting an autocollimator.

Give yourself some time and read Astrobaby's guide a few times and you will become proficient at tuning. I personally (others may have a different view) would not suggest getting the autocollimator until you understand the basics of the mechanics of the scope and a bit more experience, as the instructions alone will give you nightmares. 

I second this. This thread has definately suffered from mission creep with talk of flocking , changing out spiders etc, etc, when all you need is some experience behind the focusser with a well collimated scope. Keep it simple and build up your experience observing and with basic telescope maintenance. ABs guide and a cheshire is all you need for now and a a good few clear nights.