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who has what REFRACTOR, REFLECTOR OR BOTH


spaceboy

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What's the cool down like on a SCT??

I would estimate the 6" SCT needs a minimum of 30 minutes cool down time and the 9.25 SCT needs at least 45 minutes.

I usually move the scope to my unheated conservatory in the afternoon if I think there is a chance that I might be able to get some observing in that night, so the cool down time is never much of an issue. Though more often than not the clouds do not clear and the scope is moved back to its storage room unused...

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How about a TAL100RS I hear these are considered near to the quality of a APO

I doubt that they are, but they are very good. A long refractor, like F10 or more, will have far less of a chroma problem than a short one. With good eyepieces I don't really notice the chroma on my one unless I am looking for it.

tal01.jpg

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How about a TAL100RS I hear these are considered near to the quality of a APO

The TAL100's are very good achromats but I think "near apochromatic" is pushing it too far. The one I had was as well corrected as the Vixen 102mm F/9.8 that preceded it and that's a compliment as the Vixen's are also fine achromats.

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How dose it stand with aperture with Achro's. I hear the larger you go the more emphasized the faults are. This is why I find it a hard decision to go down the frak route. Smaller would mean better quality but bigger would mean a more deeper view. Apochromatic appears to be the perfect solution but price puts this out of the reach of most budgets. I have seen a Helios 120 on a EQ4 mount go for £125 on eBay and I kick myself every day for not bidding but at the time I was looking for a larger aperture dob to compliment my then 200K.

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Hi

Well done :)

I was hoping no one would notice.

If I took a pic now the barlow would be after the diagonal.

I had a panic attack when the scope guided near vertical last night and the gap underneath could be measured with a feeler guage !!

I'd read that barlow pre-diagonal was a better setup.

Just shows you shouldn't always believe what you read . Well perhaps for other types of scope, but not this one.

Won't do that again.

Neil

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How dose it stand with aperture with Achro's. I hear the larger you go the more emphasized the faults are. This is why I find it a hard decision to go down the frak route. Smaller would mean better quality but bigger would mean a more deeper view....

As refractor aperture increases, for a given focal ratio, it becomes more challenging to control chromatic aberration (CA). So a 150mm F/8 achromat will show more CA than a 120mm F/8, and so on.

CA can also be controlled by increasing focal ratio (slower) so an F/15 100mm achromat can be virtually colour free but the tube will be unwieldy and challenging to mount. These latter problems also affect F/8 refractors of 125mm and more in aperture.

While expensive, apochromatic refractors can be faster, therefore shorter, lighter and easier to mount.

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Thanks John.

I still have a bit of saving to do but should a 100ED come up at the right price my credit card will be taking a hit. I think it is more likely I will be settling for a 120 Achro if I can find one second hand close to home.

The results so far are still in favour of a frak.......

REFRACTOR...................44

SCT.............................21

MAK.............................8

REFLECTOR....................24

MAK-NEWT....................3

RC................................1

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I started with a 4.5" newton for my 62nd birthday (late July 2010) to "test the waters" and found I got bitten by the Astronomy bug very hard ;) I then seriously went through the refractor/reflector debate within myself and ended up with a Celestron Omni XLT 120 refractor. I then sold my newton and eventually replaced it with 8" Skywatcher Dob. And now after seeing one, I wish I had a Celestron C6 RGT refrector - maybe eventually it will replace the Omni refractor ;). This all happened within about a 5 month span........... :)

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TBH it has come as a shock how many members have refractors. When ever I have asked the REFRACTOR vs REFLECTOR I always come away with my head spinning. There always seem a steady argument for and against and there is never a clear resolve. I understand from what is said that if you can afford ed/apo optics you can't really go far wrong other than increased cool down times with triplets.

I hope it will help others that have asked the same question as I really thought it was going to be a run away win for reflectors as so many complain false colour & CA let fraks down and you get so much more aperture for the money from a flek. I know we have some rich and dedicated astronomers on the forum but they can't all be £££££ colour correct apochromatic fraks.

Thanks to everyone who has participated but there appears no doubt in my mind a refractor is worthy of it's heritage and a place in my collection. I don't suppose there is anyone near Birmingham who would let me have a quick look through their refractor ??? I say quick look as we don't seem to have much else lately :)

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TBH it has come as a shock how many members have refractors. When ever I have asked the REFRACTOR vs REFLECTOR I always come away with my head spinning. There always seem a steady argument for and against and there is never a clear resolve. I understand from what is said that if you can afford ed/apo optics you can't really go far wrong other than increased cool down times with triplets.

I hope it will help others that have asked the same question as I really thought it was going to be a run away win for reflectors as so many complain false colour & CA let fraks down and you get so much more aperture for the money from a flek. I know we have some rich and dedicated astronomers on the forum but they can't all be £££££ colour correct apochromatic fraks.

Thanks to everyone who has participated but there appears no doubt in my mind a refractor is worthy of it's heritage and a place in my collection. I don't suppose there is anyone near Birmingham who would let me have a quick look through their refractor ??? I say quick look as we don't seem to have much else lately :)

I personally dont think there is a clear "winner" between both. They both have their pros and cons in equal measure.

I personally think the BIGGEST factor and deciding factor is value for money. Reflectors are cheap(er) and offer more aperture for your money.

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