Anyone regret buying a 'Large' Refractor??

[wigggyy]

I have the Esprit 120ED you won't be disapointed I love mine and got some great images.

[pyrasanth]

I've have just faced the same dilemma.  I wanted image scale & I wanted speed. I could not afford a 36" F5 scope. I have compromised and bought a Celestron 11" F2.2 RASA. I can now use this for wide field deep sky & the C11 edge for brighter small objects at F10 or F7. I have a Hyperstar as well but that has  been negated by the RASA.

[Jonk]

I'm also in the market for a good frac.

I also want to get the Canon 70-200 2.8 IS ii....I'm guessing this will be great for large nebulae?

Mainly it'll be used for daytime photography, but I've seen fantastic nebulae photos using this lens..

Someone tell me what frac to buy for DSO imaging!

[F15Rules]

I've never regretted buying a large refractor (that was the original question:-)..

Dave

[Chris]

As a non-imager; what does a 120mm F7 frac at 840mm FL 'manage' that a 8SE with an F6.3 reducer/corrector at 1260mm can't in terms of getting closer to small DSOs?

In my head (a messy place, I'll admit) the SCT working at F6.3 is both faster and working at a greater image scale, plus potentially more stable owing to the more compact length. I'm assuming optics/mirrors aren't deficient in either respect, both are well collimated and sensor coverage isn't an issue

Is this purely a central obstruction issue and if so, what is the issue generated - Contrast? Can't that be sorted in Photoshop?

Russell

The only two things I can think of which let the standard SCT down for imaging are, 1) primary mirror flop, and 2) placing the flattener at the back of the scope is sub optimal as it can't fully flatten the field in that position.

The Edge HD varient gets round these problems by placing the flattener at the optimum position inside the scope, and also primarry mirror locks to help prevent mirror flop.

Still lots of images out there taken with SCT's, just not as many as fracs and newts from what I can tell.

[davedownsouth]

Yes. I have an 8SE, and I was very tempted to sell this on, get the Edge HD with the reducer / flattener which should on paper be the better option.  A couple of things put me off this route, i.e.; even with a dew heater / strips, the 8SE is a [removed word] for dewing up, and for me it has always restricted my viewing sessions to 3 - 4 hours at best.  Now, at this time of the year, that is going to be long enough  , but come winter, when we get those one or two lovely long clear nights, the dewing up is going to get annoying.  Being honest, this was not the really reason I did not go down this route though, it was more I have really liked my 80mm refractor, so I just wanted another one which could get me closer in.  I have had the 120mm scope for well over a week now, and the curse of the new equipment influencing the weather has certainly hit me big time and I have only managed to set it up properly once.  I thought the few shots I have got from it were very promising though and I am really looking forward to trying it out again, but unfortunately, I do not think the weather is going to allow it any time soon .

[ollypenrice]

As a non-imager; what does a 120mm F7 frac at 840mm FL 'manage' that a 8SE with an F6.3 reducer/corrector at 1260mm can't in terms of getting closer to small DSOs?

Russell

It won't 'get closer' at all, as I suspect you suspect! The thing about a good refractor is that it has very fine optics giving small, tight and shapely stars over a large chip, assuming the right flattener. Here's the full size of our last refractor image, the Leo Triplet in a TEC140. I don't regard 980mm as a 'galaxy' focal length but it is often great for galaxy groupings. I feel sure that my SCT would not give so good a result even though the FL is longer.

http://ollypenrice.smugmug.com/Other/Best-of-Les-Granges/i-NNsK787/0/O/LEO%20TRIPLET%20TEC140%202015%20web.jpg

Olly

[Davey-T]

I can't get all three in my SCT FOV.

Dave

[russ.will]

.....as I suspect you suspect!

As a non-imager, I suspect that you don't suspect that I suspect that I don't suspect to presume to suspect anything about the subject. I also suspect that if you'd just said 'star shapes', I suspect that would have been ample explanation.

I also should have suspected your response and postulated my original question with the caveat; the answer should not be what can be managed with an OTA of any sort that costs four times the amount of an 8SE.

Michael taking aside, that image (I suspect!) encapsulates the difference between imagers and visual observers. For starters, I should say that I think it is fantastic, but I mean that in both the common and true sense of the word.

In the common sense, it shows an amazing amount of detail compared to the three smudges I'm used to seeing and thus it's a joy to look at. In the true sense, I'm also aware that it's as much a result of image processing and that the photons that died on the sensor to make the image, would never look like that, no matter how many were captured and stacked.

I guess that encapsulates the differences between imagers that can magnify a 'scope's faults and an observer, that merely asks his scope to make the subject accessible.

Yours, deeply jealous of having neither the time nor climate to indulge in both,

Russell

[ollypenrice]

I hope that my are images are not, in the literal sense, 'fantastic.'  In processing you only work with what's there, you can't invent what isn't. What I'm saying is that 'what is there' in a refractor is often tighter, better resolved, than what is there in optics of theoretically higher resolution. In other words, for imaging, refractors (good ones) punch above their weight. That doesn't mean they punch above their price tag and it would be hard to argue that they did...

Whether or not they do so for visual observing has, perhaps, been mentioned once or twice before!!!   

Olly

[JDFlood]

No, but I did regret buying the 11' reflector I bought about 15 years ago. I'm definitely much happier with sharper optics. If I upgraded I would add a 6" to my Tak family. JD

[Philip Benson]

I use a TMB 152mm F8 apo and would never part with it.   Optically I have never experienced anything better.   At 16kg it is not a light OTA but the EQ8 handles it with one eye closed.  If I want larger aperture I use an Orion 16" F4dobsonian.  Not in the same class optically but visually brilliant on DSOs as you would expect.

[Physopto]

I like my WO 132mm not tried any other refractors so cannot comment. Had a Meade lx200 but nowhere as good, mainly because the mount was useless for imaging. I only wish I had bought a ~100mm like the FSQ106. I like the wider field I see in so many astro photographs. I just need more experience before I go elsewhere in astrophotography.

Derek

[DirkSteele]

Short answer is no.  But there is a caveat.  The 180mm triplet (see photo compared to my 105mm which is my most used scope) is so large and heavy that I currently use it infrequently due to it being a handful to set up and take down.  For quick one to two hour sessions after work in the week it is not appropriate to use.  However, I am intending to build it a permanent home in the future and then its use will no doubt increase substantially.

[DaveS]

Now that's just showing off    ! I know how much those things are  .

As much as I'd like (And could afford) one of those, as I'm almost exclusively an imager I'd go for something a bit smaller and faster.

[HD-AP]

Er no

Never regretted buying a large refractor ,they are old by today's standards but still hold their own today in my opinion .

VIXEN 150 ATLUX ED  AND ASTROPHYSICS  180 EDT....