How to improve visual performance of an Achromat Refractor RE EDITED

Owners of Achromatic Refracting telescopes will find that the Chromatic aberration effect or false colour creating deep purple halos around planets, bright stars and the moon may be detered from these effects. Here in this video guide we A4B we here to show you all what can be done to help reduce these effects and help improve on your telescopes performance. This is the only video guide on the net which is available which demonstrates this CA problem. For more updated video please subscribe onto my channel on:

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David Dowson says:

hi martin just to say what a brilliant job you are doing.

Kelly Taylor says:

After viewing the images you can see
light scatter from the internals of telescope tube.
Protostar makes a flocking material for very low cost that will improve the contrast greatly.
The brightness in the center of the field shows this issue.
I have flocked every scope I have and the difference is worth the effort.
Google Protostar Flocking.
Highly recommended.

geoffers77 says:

PS Martin, I have the 2.5 and 5X POWERMATES  AND THEY ARE  SUPERB, CHEERS , NOW GOING TO BY THE Explore Scientific 80 mm Carbon Fibre Triplet ED , HOPE YOU APPROVE Martin LOL

long knight says:

Get a minus blue filter and it will be fine.

Dan Kahraman says:

You can collimate the lenses with the push-pull screws. This doesn’t affect how the lens elements are oriented with respect to each other. I have the Baader semi-apo filter and it does reduce the CA in achromats.

Ted Williams says:

I first want to say great video! I recently purchased a Achromatic AR102mm Telescope from Explorer Scientific. However the only issue I have was with the filter and your images. You’re taking pictures of the outside in daylight and comparing Semi-APO filter from Baader. Wouldn’t it have been best to do night time photos of the moon or a planet per say to get the true spectrum and color since the bright sun or atmospheric spectrum reflection can ruin an image per say.

I heard people can use a CLS filter along with either the Baader Fring Killer filter or the 945N Yellow Longpass filter and that will eliminate the CA all together.

Still a great video but I would have done night shots so people can see it from a night time perspective. If they are using this kind of scope for nature shots then yes this would be cool to see.

Dennis Rogers says:

this company know how to make decent telescopes and hardly any false colour and we’re all doublets no triplet objectives back then.

southernexposure123 says:

Thanks for the video. You answered a lot of my questions.

TheT0nedude says:

Fast achromats excel at terrestrial and wide field views of dso’s, but pumping the power too much and the image breaks down very quickly due to the obtrusive secondary spectrum. Hence they are not designed for planetary and high power work. But for value for money and low power wide field crisp views they can’t be beat…

menacegtr says:

hi to you, I am liking all your videos and hope you can give me your view on the skytravel 120 mm AZ3. I want this scope for terrestrial  use and the moon and hopefully further. If any good what Barlow and eyepieces would you recommend. Regards

Kelly Taylor says:

I use this filter and add the Badder
IR/UV filter with it.
Once you see the difference you will understand.
The filters can be threaded together.
Piggybacked if you will.
I use them on my 204mm F/9 refractor
as well as my 150mm F/15 refractor
and my 150mm F/5 refractor.
Also to note a Good barlow place between
diagonal and focuser improves things as well.
Takisha makes a prism 1 1/4″ that also helps the simple two element refractors.

erics vids says:

I wished you would sort some sort of mike out on your reviews cant here you

sam lambrechts says:

That’s my scope 🙂 great video, Martin 😉

Gerard O'Born says:

Great work Martin. Many thanks.

erics vids says:

hi have you reveiewed the altair astro 152 with the 3″ focuser thanks

southernexposure123 says:

I just gave a friend a link to this video. I’m sure he’ll click on several of the others. Good work.

Robert Cole says:

Black edging optics reduces BDRF improving contrast by eliminating optical noise by about 1 magnitude will not effect chromatic aberration this is caused by badly designed lenses

geoffers77 says:

HI Martin ,just discovered you Vids Brill , you are doing a fantastic job mate. I have been doing astronomy for twenty plus years and you have taught me a few things, nice one So pleased you have gone away from yhe Dreaded Mobile Vids Cheers

Mohammad Was A PEDOPHILE says:

Great,just need a bit of a jump in audio levels,too low.

jay racz says:

I have the Skywatcher 105/500. l found one of these filters locally for a deal. I decided to give it a try after watching this vid. I did not find it helped that much to be honest. I was comfortable taking my scope apart so I decided to take a sharpy to the lens sides. That actually made a better improvement then the filter. I then decided to do all my eye piece lenses as well and my prisim. All these improvements worked real well. l also use the dew cover during the day. Cutting down the amount of light works well for day use.

Dennis Rogers says:

The reason you get CA on modern refractor a chromatic lens is the f ratios are too loo

Have had way back in the late 70’s an f16 102mm refractor, hardly any noticable CA.

They used to make refractor back in the 60’s that preformed as well as triplets.

They make them with small f numbers now as its cheaper.

Utrion made the best refractor which could compete with any triplet but very expensive and very long.

They can do it easy, but don’t these days to keep costs down.

Zombie Woof says:

Very helpful, thanks!

Matthew Knight says:

so many ad’s in the video gg gets annoying going about making money on YouTube the wrong way man you only need 2-3 ad’s you’ve like eh 8 ad’s in this video man 🙁

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