I think I've become a Refractorholic.

[osbourne one-nil]

A couple of months ago, I started pondering about my next purchase...the telescope to plug the gap between my TV85 and my Sumerian Optics 10" Dob. In the end I went for a Celestron C6. 

Tonight, I took a very rare night off and set up my C6 on its lovely ZEQ25 mount ready to spend the evening staring at Jupiter and Mars. I also took out my puny little TV85 on its non-driven Porta II, just in case. 

Guess which one showed by far the nicest views......yep. 

Weird isn't it. No matter how much you read about the subject, until you get a side-by-side comparison between two totally different scopes, you don't realise that size isn't everything. I assume the C6 has cooled properly; it's been outside in the shade from lunchtime to now, but there just isn't that moment when everything's perfectly sharp, and while the image is bigger, I could see FAR more detail through the Televue with a 7mm Ethos. 

To think - a few weeks ago I was close to placing the Televue and its mount on the market!

[oldpink]

sometimes size isn't everything

[Stu_2011]

I'm the same really, love my refractors for the pure views you get. However I do believe that on planets SCTs win out when you get to 8" / 9.25" or bigger. I have a couple of 80 mm triplets (one being a Lomo lens WO which is one of the finest 80mm triplets ever made) but on planets my CPC925 wins out easily.

You just need lots of scopes I reckon!

Sent from my iPad using Tapatalk

[cotterless45]

Had comparison views last night, 10" Lightbridge vs 12" OO vs C6r. The frac won outright with Mars.

This week on ebay , a 102 Vixen on it's mount went for £128. Nobody wants the old stuff !

Nick.

[chiltonstar]

It is said that the only known cure for being a refractorholic is to go out and buy another one...... (only works for a few months though).

Chris

PS They do give lovely views though, don't they!

[osbourne one-nil]

This is fantastic; please keep going because soon I'll have to buy another one so I don't hurt anyone's feelings.

There is a Takahashi FS102 going on ukastrobuysell, which is tempting, but I'm uncertain whether my Porta II would carry it. I was also uncertain whether I'd actually notice any difference over my TV85 as it's not a huge increase, but then Ed Ting's gone and posted  review where he says the difference between an 80mm and a 90mm is noticeable.

I do need lots of scopes, and lots of mounts....and lots of money.

[ronin]

I have found exactly the same, my best views - often of planets - have always been better with a refractor. As you have said the image is not as big but the definition outweighs this by a reasonable extent.

[osbourne one-nil]

Perhaps my C6 needs collimating, but I just couldn't get it to snap to focus. In the TV85, however, the planet snapped right in there and looked gorgeous hanging in the darkish sky (the Moon wasn't too far away, of course). What I really liked though was a definite and quite sharp darkening down the left hand limb, which, looking at maps, I assume was Syrtis Major? Whatever it was, I couldn't see it in the C6. Also, I had a 7mm Ethos in, giving a magnification of around x85, and I could track nicely with the slow motion controls on the Porta II.

The best views of the night were with my Explore Scientific 9mm (100 degree) eyepiece though. It might "only" offer x67, but it looked wonderful and showed the full disc of the Moon very comfortably.

The ES102ED looks good value. Hmmmmmmm.

[Owmuchonomy]

What an interesting thread.  Reading the rest of SGL you would think an SCT was unbeatable on planets.  I have over the past 2 weeks used my 9.25 XLT SCT AND an AA 102 EDT.  My own experience this week is that Jupiter is best observed through the frac; it even picks out round moons!  The resolution appears much higher although the tech heads say that's impossible.  Mars is my next test for the 9.25, which actually was disappointing through the frac on Tuesday.  A scope for each planet? Ouch!  My seeing hasn't been great so far as I only managed 140x.  I'm not a technical guy so I can only go on what I see.

[GuillermoBarrancos]

What an interesting thread.  Reading the rest of SGL you would think an SCT was unbeatable on planets.  I have over the past 2 weeks used my 9.25 XLT SCT AND an AA 102 EDT.  My own experience this week is that Jupiter is best observed through the frac; it even picks out round moons!  The resolution appears much higher although the tech heads say that's impossible.  Mars is my next test for the 9.25, which actually was disappointing through the frac on Tuesday.  A scope for each planet? Ouch!  My seeing hasn't been great so far as I only managed 140x.  I'm not a technical guy so I can only go on what I see.

The resolution in the 9.25 SCT is much higher than the 102 refractor.

With an SCT you are more than likely to go for higher magnification views (due to much longer focal length) than with a refractor and then with bad seeing conditions the views through the SCT will look worse than through the refractor.

Caused by seeing conditions and not the optics.

It would be a much more honest comparison, when both refractor and SCT are properly cooled down and than use matching EP´s in both SCT and Refractor, so the magnification (focal length) is the same with both scopes.

When you do that, you will notice the difference in views might not be that much different afterall. In fact, due to the sheer aperture difference between the 9.25 and 102, you should be able to see more details in the 9.25 SCT at medium power.

PS. Also don´t rule out bad collimation of the SCT as a possible factor.

[Owmuchonomy]

The resolution in the 9.25 SCT is much higher than the 102 refractor.

With an SCT you are more than likely to go for higher magnification views (due to much longer focal length) than with a refractor and then with bad seeing conditions the views through the SCT will look worse than through the refractor.

Caused by seeing conditions and not the optics.

It would be a much more honest comparison, when both refractor and SCT are properly cooled down and than use matching EP´s in both SCT and Refractor, so the magnification (focal length) is the same with both scopes.

When you do that, you will notice the difference in views might not be that much different afterall. In fact, due to the sheer aperture difference between the 9.25 and 102, you should be able to see more details in the 9.25 SCT at medium power.

PS. Also don´t rule out bad collimation of the SCT as a possible factor.

Thanks for the info.  Both scopes used at 140x max so far and collimation of the SCT is bang on.  I even used the same diagonal.  I'll have another bash this weekend.

[Merlin]

When it comes to star clusters, nebulae and galaxies, a bigger, well-made, Newt will outperform a smaller cat or frac.

[osbourne one-nil]

A scope for each planet? Ouch! 

At least with Pluto's demotion we only need eight...or maybe just seven if we don't count the Earth. Sorted!

PS. Also don´t rule out bad collimation of the SCT as a possible factor.

Yeah, wondered this last night as the out of focus images looked a bit odd - not the nice lovely clean discs in the refractor. Need to suss out how to collimate an SCT.

[F15Rules]

Without wanting to open up once more the Frac vs SCT vs Newt vs everything else debate, I do think the British weather makes all the difference. It's rare to get two nights of exactly the same seeing, whereas for example a lot of Cloudy Nights observers enjoy dry, desert skies where the atmosphere allows the optics to give of their best.

After many years of using refractors and agreeing with the OP that they give much the most pleasing stellar and planetary images, I concluded long ago that fracs are just less susceptible to these atmospheric changes and will, on any given night, deliver a higher percentage of their potential performance than any other optical system - bar none.

Dave

[perfrej]

Yep! Once you go frac you never go back

(I have two more on the way in)

/per

[John]

I was a "refractor only" observer for many years and I still enjoy them today. 3 of my 4 scopes are refractors. I've found though that a newtonian with good optics, in good collimation, can provide really excellent views of traditional refractor targets such as the planets, the moon and binary stars. I have to admit that my 12" F/5.3 Orion Optics based dobsonian has become my most used scope over the past year with the refractors not really getting too much use in all honesty. And I never thought this would be the case .... 

[russ.will]

Yep! Once you go frac you never go back

(I have two more on the way in)

/per

I dunno. I've had three fracs and four Newts of varying sizes and focal lengths/ratio and decided the winner was....

One of each!

Russell