4" DIY Refractor

Hi all, my 4" DIY refractor telescope had first light in November 08, rendered crisp images of moon & jupiter, this achromat lens was bought from Cloudy Night Telescope Reviews classifieds last year. Project involved lot of machinining & fabrication work. I had to run around places to get things done, but i enjoyed this project. Optical tube weighs 8 kg's. This is my second BIG project after my DIY floorstanding speakers.

Carton had an excellent reputation years ago for manufacturing scopes that rivaled Unitron in terms of quality. Scopes came with nice optics and fine mechanical quality. Astro-Physics also used the Carton mounts with their APOs in 1980.

Review on CARTON 100mm f/13 at Telescope Reviews

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Hi Anil

Thanks for sharing your work on the refractor. It is truly great professional looking telescope u have there. Hope to see more posts about your scope and best of luck for all your future projects.

Clear skies
Ravi

Great work Anil.

Fantastic!!! The progression shows every step in great detail.
Perhaps you could also write a small section about the challenges faced and how you overcame them so that everyone can learn from your experience.

Congratulations!!

Hi Anil,

Congrats, on the new scope...As far as I know this is the best home-brew telescope i have come across...Its optical quality and mount quality is excellent..( no vibrrrrrationnn!!!!!)& good resolution for a 4 inch refractor.

I should remind readers that the effort put by Anil for this project is tremendous...!!! Organizing for Raw material and getting it machined to perfection and last but not the least good paint job.

Its a signature for Anils passion and attention to detail...a lesson or two to be learnt as to how meticulous planning and vision will help. All these has been done with limited resource and time.

Once again good show Anil and the pic. says it all....

Put it to use and enjoy.

The telescope looks great and performs ever greater. In fact, the advantage of not having a central obstruction is quite apparent. The contrast is very good and resolution is great. A project very well executed. Keep it up Anil. Hope you will complete the drive assembly also at the earliest.

Thanks to Ravi, Vishwa, Kiran, Prakash & Chandra for comments.
Drive assembly is getting ready, hope to complete before next outreach session


Anil

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A small scope that gets used often is a better investment than a big scope that stays in the closet

Hi Devdatta, welcome to AAC, thanks tor the comment.
Light path in a PVC tube bends in case of long refractors [f/10 & above] this results in alignment problems. In fact i tested my lens with PVC tube first.
Since i am a hardcore DIYer i always prefer professional looking scope, so weight is not a issue here. Because for this reason i went for aluminium tube. Aluminium is easy to work with. In case of PVC tube surface is more prone to damage & paint does not stick to it. My OTA is powder coated, looks professional!!!!

At ABAA we use PVC tubes for 6' & 8' mirrors, they are quite good & sturdy for reflector telescopes. I spent 22k for this project.


Check this for more info:

My Carton Refractor

My DIY floorstanders






Regards,
Anil






[quote="devdatta"][font=Verdana]
Hey, first of all, thanks for letting me know about this place. The telescope looks quite good. very sturdy. and the resolution power of the lens is quite good i must say. I am curious about one thing though. It looks like you've used metallic tube. Have you thought of using a lightweight PVC pipe rather than the metallic? If yes, what was the reason of not using it? Some of members of our organization have made similar telescopes using PVC pipe. they work great and are of less weight. btw, the mount is just amazing!!

What's overall amount of money you had to spend while building this??