Should I buy a 'frac?

[DRT]

This probably sounds like a stupid question to most people here but I can assure you it is completely genuine.

As can be seen from my signature and the various threads I have participated in I own an 11" Schmidt-Cassegrain and an 8" Dob. I have never looked through a Refractor.

I see lots of discussion about Refractors and imaging. I am an observer and have no interest in imaging other than putting my iPhone up to my eyepiece and clicking.

So, from that standpoint, is there any point in me owning a Refractor?

What would it let me see that I can't with my other scopes?

What size of aperture would I need to compete with the scopes I already have?

Would I need a separate mount or could I piggy-back the CPC to take advantage of the GOTO/Tracking (remember I am not imaging, so no equatorial stuff required)?

Is there a place called Astronomers Anonymous where I can go to tell like-minded souls "Hi, I'm Derek, I'm addicted to spending money on things that point at the sky?"?

[rowan46]

I really don't think there is a frac that would compete with your present  scopes unless you were to sell your scopes and probably your house as well. however a small frac makes a nice grab and go  with no cool down needed. ultimately apparure rules  a 100mm apo might give your 130p a pasting in the contrast and sharpness stakes  but it wouldn't see any more on dso's and against the 11" no contest on dso's

[ronin]

If you have no interest in imaging then No.

You have a good set of visual scopes getting a refractor is not likely to add to what either of them can do.

[swamp thing]

Can't see any reason for you to buy one...

However, when did something as silly as reason ever stop anyone.

[lensman57]

You seem to be grared up for visual-planetary stuff. The cpc is also on a fork mount that is of no use to any other scope. Unless you just want a short frac to dabble in imaging, anything else, Apos or EDs,  to compete with your present aperture sizes will cost a great deal of money and on the top you need to spend another £1000.00 for the mount at the absolute minimum.

Sounds like a very expensive itch.

A.G

[Stu]

This probably sounds like a stupid question to most people here but I can assure you it is completely genuine.

As can be seen from my signature and the various threads I have participated in I own an 11" Schmidt-Cassegrain and an 8" Dob. I have never looked through a Refractor.

I see lots of discussion about Refractors and imaging. I am an observer and have no interest in imaging other than putting my iPhone up to my eyepiece and clicking.

So, from that standpoint, is there any point in me owning a Refractor?

What would it let me see that I can't with my other scopes?

What size of aperture would I need to compete with the scopes I already have?

Would I need a separate mount or could I piggy-back the CPC to take advantage of the GOTO/Tracking (remember I am not imaging, so no equatorial stuff required)?

Is there a place called Astronomers Anonymous where I can go to tell like-minded souls "Hi, I'm Derek, I'm addicted to spending money on things that point at the sky?"?

Hi Derek,

To answer your last question first, I think you already found it here? ;-) Most of us are just as bad!

I agree with the comments above in that buying a frac won't compete in absolute terms with your other scopes. You will generally always see more in terms of both resolution and brightness through a decent large aperture scope.

However..... You wouldn't expect someone owning 5 of the pesky things to give up that easily would you? :-)

I would not suggest piggy backing on the CPC1100, although it would work with no problems, I think that would lose the convenience you would gain from a smaller scope.

So... How about a 4" frac? Either something like a TAL 100RS (which have a great reputation but I've never looked through one), or an ED doublet on an Alt Az mount like a giro or similar? This would be very quick to set up, would need little cooling time and allow you to catch small observing opportunities. The TAL is much lower cost, but also has a long focal length so is more suited to doubles and planetary than Widefield, so perhaps an ED doublet is better.

I will confess that whilst I see a lot more through my 12" dob, I enjoy the views through my fracs more just because of their nature. They give such lovely pure star shapes, they cut through poor seeing very well so quite often my 6" will give as good an image on planets as the 12", and the contrast is wonderful.

I know you've discussed getting a wider field in another thread. I have a 4" apo triplet with 690mm focal length. With a 31mm Nagler this gives a 3.68 degree field of view. It is at its best under dark skies but with good dark adaptation and, where relevant, an OIII or UHC filter, the views of open clusters and nebulae are gorgeous. This scope will also cope with x230 or a bit more for very nice planetary views. You don't need a triplet for this, a good ED doublet would be fine but make sure the focal length is right.

Examples of what you can fit in this fov below.

This last one is Kemble's Cascade, normally a binocular object but will fit into the fov of a Widefield frac.

Don't buy a frac to compete with, or beat your other scopes because it won't. Buy it to complement them and show you a different perspective on the same objects, or to allow you to see large objects in their entirety.

I'll be quiet now :-)

Stu

Sent from my iPhone using Tapatalk

[swamp thing]

One word of warning, if you get the TAL your 31mm T5 won't focus there isn't enough in travel. I tried mine in Astro baby's and no luck.

[Stu]

One word of warning, if you get the TAL your 31mm T5 won't focus there isn't enough in travel. I tried mine in Astro baby's and no luck.

There you go, all the justification you need for a nice apo triplet ;-)

There is another very valid point which I read about the other day. Some of the entry level triplets seem to be being specifically designed around imaging so focussing with diagonals and eyepieces may need extra extensions or other changes. So perhaps sticking to a known quantity would be better.

The 'trouble' with the ED100 and 120 is that at 900mm focal length you wouldn't quite get the same fov experience. John has a lovely Vixen 102 which does the job, something similar would be nice.

Stu

Sent from my iPhone using Tapatalk

[ollypenrice]

The only rational reason would be to have a shorter focal length for a wider field of view. A big refractor with a focal length similar to what you have will not give any rational benefits. However, I couldn't live without a short FL refractor for the widefiled views, the entire Veil Comples, the Rosette, the Double Cluster framed with stock 11, etc etc. This could piggyback on your SCT if light. (I have a TeleVue Pronto and light it ain't...)

Now for the irrational reasons. There is              no doubt whatever that the finest views of the night sky come from insanely expensive apochromatic refractors. Winding up the Dob Mob? Me?? Would I do that? (The smilies have stopped working for me but I want one of a saint and one of a little angel to put here now...) Heh heh.

Seriously, I love the view through the TEC140 Apo and don't feel it can be matched at similar aperture by anything other than another premium apo but I bought it for imaging. I couldn't justify it purely for visual.

Or could I????

Olly

[chiltonstar]

Yes, of course (to the OP's question).

Chris

[brantuk]

Hi Derek - if you'd like a look through a frac you'd be very welcome to drop over to my place some time for a session. I have a couple of acro's, a duoblet, and a triplet, so you'd get a good idea to compare with your other scopes. I bought the first one out of curiosity and a vague desire to do imaging. So far I've used them mostly for observing and a tiny little bit of photography.

Alternatively you could attend a session with East Mids Stargazers and I'll bring one along with me.

[Charic]

Interesting..........Unless the TAL 100 Refractor can better the image of my 8" Reflector for visual use, then my search is over.

[swamp thing]

Interesting..........Unless the TAL 100 Refractor can better the image of my 8" Reflector for visual use, then my search is over.

They're good, but not that good.

[Charic]

Steve....I was in favour or either scope when I first started on SGL, but the overwhelming advice at the time was to get the 200P. Ive had no regrets since, apart from the extremely light nights I'm experiencing at present. But the thought of a Refracor re-occured last Month on a visit to North Wales. Portability and ease of use for planetary use was my thought process.

[Jim Steele]

Portability and ease of use for planetary use was my thought process.

That's why I bought my Tal. Quick and easy to setup, the tube is surprisingly light and can be carried via its dovetail one handedly.

I'm sure the 200p wood give brighter images but it would spend most of the time in storage.

[JG777]

How can you possibly get through life without a decent refractor?

[michael.h.f.wilkinson]

I use an 80mm F/6 triplet next to my C8, but not often. It is great on certain targets (listed above), but I did buy it with imaging (plus wide-field views) in mind. For wide-field targets I use the 15x70 bins FAR more often, despite these being of lower quality optically. I made a comparison here

http://stargazerslounge.com/topic/193207-tales-from-santa-luce-tuscany-episode-v-great-globular-and-wide-field-shoot-outs/

Note that the conclusion is to keep both. Incorrigible, aren't we

[todd8137]

I sold my carbon fibre edt 5" frac to,fund a 16"" hand made mirror set,and truss tube ect and boy am glad I did as already said you need a good frac,and they not cheap and you may not be that happy

Pat

[swamp thing]

How can you possibly get through life without a decent refractor?

Look through other people's at group sessions

Skinflint of Sutton

[D4N]

I can carry my lil frac and a mount for it in one hand... don't try that with an 11" reflector

If you need a grab and go they are great

Sent from my iPhone using Tapatalk

[DRT]

Hi Derek - if you'd like a look through a frac you'd be very welcome to drop over to my place some time for a session. I have a couple of acro's, a duoblet, and a triplet, so you'd get a good idea to compare with your other scopes. I bought the first one out of curiosity and a vague desire to do imaging. So far I've used them mostly for observing and a tiny little bit of photography.

Alternatively you could attend a session with East Mids Stargazers and I'll bring one along with me.

That is very kind, Kim. Damian is going to text me the next time you are all heading to the dark site and I'll pop down if I'm at home. I am only 30 minutes away

Thanks to all the others for the kind words of encouragement in my continuing quest to empty my bank account

[michael.h.f.wilkinson]

My C8 is practically as much grab and go as the frac. Given that aperture is king for visual, the C8 gets much more use.

[Tim]

I wonder if all this "visual astronomy" malarkey will catch on????

Blow all your wonga on a nice 6" apo. The views on clusters, bright nebula, planets, comets are super crisp, colourless and all round snap-to focus lovely. Take a pic through that with your iphone and you will fall right down the hole into the dark side

Cheers

Tim

[Luke]

Fracs are pretty good for solar observing and imaging! With the correct solar safety filters, of course! One big plus is you can use compatible fracs with a Herschel wedge for great views of the Sun in white light. You don't need huge aperture for the Sun. My tiny grab and go 60mm scope does pretty well on the Sun with a Herschel wedge!

I also like fracs for quick views/low hassle. My most used scope at the mo in these Summer months is an 85mm and I was out looking at the Moon the other night with a 60mm. Would barely make a finder scope for some of the dob mob!

Each to their own. I haven't yet met a telescope I didn't like. I'd love to try a Mak one day.

[wavydavy]

I think most comments above are completely right, theres no real point to getting a refractor.