C14 HD and UK seeing

[seiko]

I'm tempted to purchase a new C14 HD on the CGE Pro mount but wanted to first check whether the UK skies and general seeing conditions would ever support the C14? I'm in the south east.

Im also considering the CPC11 HD as it would be easier to set up. Initially either one would be set up and taken down. As these would be long term investments they'd eventually be housed in a permanent observatory.

 

Does anyone have a C14 in the UK? Thoughts compared with the C11?

 

Lastly, I'm also going to look at the Mewlon 210. This would represent the TSA120's partner for lighter push to alt az mount viewing. The scope family would then consist of ...

a small 120mm (TSA)

mid 210mm (Mewlon)

and larger ?

 

So is the C14 going to reward me here in the UK from a light polluted location for mostly visual observing?

 

 

[theastrodragon]

Are you looking at planets of faint fuzzies?

If planets, a C14 is overkill.

If faint objects, the bigger the better even if you do have light pollution.

I think you will find the C-11 WAY easier to set up. down, and the best scope is one that's easy enough to use often.

[seiko]

I'd no doubt start on the planets but globulars and some faint stuff would be nice. I'd like to see Pluto for example just to cross it off my list.

[Peter Drew]

I have two 16" Meade SCT's, these give excellent lunar and planetary images on average or better nights here in the NW, the SE should offer  better conditions.

[michael.h.f.wilkinson]

I have seen some stunning planetary images taken with C14 and similar aperture scopes in our climate, so I do not think it will be overkill. Would love to own one myself at some point. I have some doubts about the necessity of the HD bit for planetary imaging and visual, as compared to the regular C14

[Chris]

12 hours ago, theastrodragon said:

Are you looking at planets of faint fuzzies?

If planets, a C14 is overkill.

I'm not sure why you think this? Damien Peach uses a C14 for planets and he's arguably one of the best planetary imagers out there. The more aperture you have the more resolution. Smaller scopes can cut through bad seeing better than larger apertures but I'm not sure a C11 would cut through bad seeing that much better than a C14. An ED100 or ED120 would be a better idea in really bad seeing.

54 minutes ago, michael.h.f.wilkinson said:

I have some doubts about the necessity of the HD bit for planetary imaging and visual, as compared to the regular C14

The HD's definately work better for visual if you are using super or hyperwide EP's, this was very noticeable when I went from a C8 XLT to a C8 Edge HD. I also thought they were slightly sharper on axis, and at the time found some info on the net to support this.

I think Stu had an HD for a while? I wonder if he ever had the vanilla C8 so he could compare?

I do miss the HD.

[Owmuchonomy]

Personally I wouldn't go the HD route for visual I can't see what advantage you will get.  I have a 9.25 SCT here in the NE which benefits from a permanent set up and thus permanent ambient temperature adjustment which believe me is critical. It would be more so on a 14". The views are pretty good but more aperture via my 12" Dob gives a marginally better view.

[theastrodragon]

9 minutes ago, Chris Lock said:

I'm not sure why you think this? Damien Peach uses a C14 for planets and he's arguably one of the best planetary imagers out there. The more aperture you have the more resolution. Smaller scopes can cut through bad seeing better than larger apertures but I'm not sure a C11 would cut through bad seeing that much better than a C14. An ED100 or ED120 would be a better idea in really bad seeing.

The HD's definately work better for visual if you are using super or hyperwide EP's, this was very noticeable when I went from a C8 XLT to a C8 Edge HD. I also thought they were slightly sharper on axis, and at the time found some info on the net to support this.

I think Stu had an HD for a while? I wonder if he ever had the vanilla C8 so he could compare?

 

Because he's talking about visual, not imaging.

A 14" has a resolving power that is rarely attainable in UK skies. Now if we were talking about a fixed scope in a dome, I'd say still go for the 14, because its still going to have better light grasp.

But he says he's going to be setting it up. This is HARD for a scope the weight of a C-14, a C-11 is a lot lighter, and you don't need as big a mount. If it gets hard, people tend not to use the scope as much.

Whether the HD is better than the base model I don't know, I've never used one.

[Chris]

8 minutes ago, theastrodragon said:

Because he's talking about visual, not imaging.

A 14" has a resolving power that is rarely attainable in UK skies. Now if we were talking about a fixed scope in a dome, I'd say still go for the 14, because its still going to have better light grasp.

But he says he's going to be setting it up. This is HARD for a scope the weight of a C-14, a C-11 is a lot lighter, and you don't need as big a mount. If it gets hard, people tend not to use the scope as much.

Whether the HD is better than the base model I don't know, I've never used one.

Ok fair points. I was concentrating more on the permanent obsy he want's for it, but yes the C14 would be a literal pain to setup in the meantime. I can't see the effect of seeing conditions being that much different between the C11 and C14 but I'll never have the money to do that comparison.

[Stu]

Just to add to Chris' comment, although I've never tried the non HD version, I really enjoyed my 8" EdgeHD and found that the field was nice and flat for visual use with widefield eyepieces. I used a 21 Ethos and 31 Nagler in mine a few times and was always pleased with the results in terms of edge sharpness.

I am a bit picky about star shapes and don't particularly like the slight fuzziness you get with SCTs on brighter stars, but once you get away from these there is no doubt that they perform very well.

I would tend to agree that there wouldn't be much to choose in terms of seeing performance between the C11 and 14. As Chris says, a much smaller frac would probably be more help in these conditions. I would concentrate on the practicalities of setup/breakdown and cooling times in order to make a decision.

[Grotemobile]

https://www.harrisontelescopes.co.uk/acatalog/Meade_LX200_ACF_12_Telescope.html

How about this. Lot easier to set up than the CPC 1100 HD  scope.

Bigger scope as well. It has got manual controls as well, which the CPC

scopes don't have.

[michael.h.f.wilkinson]

I use a Nagler 31T5 "Panzerfaust" and LVW 42mm in my C8, and cannot notice much loss at the edges. I would like to see a head-to-head with an Edge-HD before drawing any conclusion. Setting up a C14 needn't be a huge hassle:

 

[Owmuchonomy]

1 hour ago, Chris Lock said:

I'm not sure why you think this? Damien Peach uses a C14 for planets and he's arguably one of the best planetary imagers out there. The more aperture you have the more resolution. Smaller scopes can cut through bad seeing better than larger apertures but I'm not sure a C11 would cut through bad seeing that much better than a C14. An ED100 or ED120 would be a better idea in really bad seeing.

The HD's definately work better for visual if you are using super or hyperwide EP's, this was very noticeable when I went from a C8 XLT to a C8 Edge HD. I also thought they were slightly sharper on axis, and at the time found some info on the net to support this.

I think Stu had an HD for a while? I wonder if he ever had the vanilla C8 so he could compare?

I do miss the HD.

Aaahh, I wondered if the flat field could be incorporated into visual. That's interesting.  There is a white paper on the HD technology that I did skim over. It can be viewed via the FLO blog from memory.

[Chris]

Thanks, check out page 5 which shows better on axis performance by the Edge HD compared to a classic C8.

http://www.celestron.com/media/796136/EdgeHD_WhitePaper_FINAL.pdf

[michael.h.f.wilkinson]

3 minutes ago, Chris Lock said:

Thanks, check out page 5 which shows better on axis performance by the Edge HD compared to a classic C8.

http://www.celestron.com/media/796136/EdgeHD_WhitePaper_FINAL.pdf

Interesting stuff. I must say that at the low magnification of the C8 with the Nagler 31T5, the coma isn't that evident. I would really need to do a side-by-side comparison

[pyrasanth]

I use the C11 Edge & it is capable of producing stunning detail when the seeing conditions are good. Sadly that does not happen enough as I suffer from poor seeing however I don't photograph planets much as my hunting ground is in the deep sky fuzzies so the telescope does well. The Edge series are more suited for imaging.

I'm going to upgrade to a C14 in the next few months to continue my deep sky hunting with a camera. Seeing is important for planets but not so for fuzzies- they need light, focal length & processing care.

A lot of people are put off by the sheer weight of the C14 & are put off by sliding the dovetail into the clamp. However there is a way around this making set up much less of a chore. Remove the rail- its only bolted on with 4 allen headed bolts. You then need to fit a set of Parallax rings to your mount- get a saddle extension if you need to. The OTA can then be placed between the rings with very little effort & firmly locked in place. This is a much more rigid & convenient solution than faffing around with a rail!

[ollypenrice]

Maybe we should let Damian Peach speak for himself. 

"When we examine everything that makes a telescope great, there are many issues to take into account. Cost, user friendliness, optical & mechanical quality, potential performance. I think when we take into account all of these issues the C9.25 really is a rarity in today’s flooded “advertising rich” market.

 

There really isn’t much to say regarding this telescope. The images say it all. Before I obtained the images I have with this telescope I wasn’t of the opinion such results were possible with a telescope of less than 10” aperture. The C9.25 has changed my views, and proven it self to be a first-class performer. Visually, under excellent seeing Saturn doesn’t look any different to how it did through my excellent C11, and the images produced are as good.

 

When you consider the price of this OTA at $1300-1500, it really is a major bargain in today’s market. It delivers in so many areas – quality, portability, user-friendliness and flexibility. Is this C9.25s long standing reputation really a reflection in how it really performs? – Absolutely."

 

I think that the C14 is unlikely to out perform the smaller ones except under superb seeing. Damian Peach does his best stuff with a C14 but from Barbados.

 

For me the C14 has a major drawback as a visual scope. Its focal length is nearly four metres. We have a 20 inch with a focal length of just over half that. The implications for field of view are pretty serious and you'd have to be sure you didn't mind being locked into such tunnel vision for deep sky targets. If you don't mind, that's fine. Personally I already feel hemmed in at 2.5 metres by my 10 inch SCT.

 

Olly

[Stu]

9 minutes ago, michael.h.f.wilkinson said:

Interesting stuff. I must say that at the low magnification of the C8 with the Nagler 31T5, the coma isn't that evident. I would really need to do a side-by-side comparison

It would certainly be interesting to do a visual side by side to see if there is much difference. I can only report on what I saw with the Edge which I had, having not owned a standard unit.

One possible negative for the Edge is a probable slower cool down time because the baffle tube is effectively blocked by the additional optics. They do have small vents  but I suspect a standard scope with an SCT cooler would be better in this respect. I believe you can get fans which fit to the Edge cooling vents which seem like a good idea.

[pyrasanth]

4 minutes ago, Stu said:

It would certainly be interesting to do a visual side by side to see if there is much difference. I can only report on what I saw with the Edge which I had, having not owned a standard unit.

One possible negative for the Edge is a probable slower cool down time because the baffle tube is effectively blocked by the additional optics. They do have small vents  but I suspect a standard scope with an SCT cooler would be better in this respect. I believe you can get fans which fit to the Edge cooling vents which seem like a good idea.

Cool down is not an issue with the C11 if the telescope is kept out of doors & certainly it is a far more convenient instrument if it is permanently mounted. I have never suffered from any issues with cool down other than very rapid focus changes which is I guess the downside of an aluminium OTA. I read, so have not confirmed this, but the Edge 14 is remarkably thermally stable for an OTA of its size which flies in the face of convention.

[ollypenrice]

The alternative to cooling down is insulating, which is the preferred route on the Continent these days.

Olly

[michael.h.f.wilkinson]

For purely visual use, a big Dobsonian is near impossible to beat, I must agree with Olly. Having said that, I have seen many planetary imaging results with C14s which best C11 and C9.25 results, even from these latitudes. Yes, you do need really good seeing, but even my little C8 needs that.

[Stu]

3 minutes ago, pyrasanth said:

Cool down is not an issue with the C11 if the telescope is kept out of doors & certainly it is a far more convenient instrument if it is permanently mounted. I have never suffered from any issues with cool down other than very rapid focus changes which is I guess the downside of an aluminium OTA. I read, so have not confirmed this, but the Edge 14 is remarkably thermally stable for an OTA of its size which flies in the face of convention.

Well.... cool down is rarely an issue for scopes kept out doors???? Ability to keep up with falling temperatures during a night's observing/imaging is probably more important in your case, but the OP was not discussing this as permanently mounted as far as I'm aware?

[pyrasanth]

12 minutes ago, ollypenrice said:

Maybe we should let Damian Peach speak for himself. 

For me the C14 has a major drawback as a visual scope. Its focal length is nearly four metres. We have a 20 inch with a focal length of just over half that. The implications for field of view are pretty serious and you'd have to be sure you didn't mind being locked into such tunnel vision for deep sky targets. If you don't mind, that's fine. Personally I already feel hemmed in at 2.5 metres by my 10 inch SCT.

 

Olly

The C14 is a big instrument & not a cheap investment either when you consider the mounting requirements to get the best from it- it is simply enormous when compared with the average back garden telescope & thus the savvy astronomer would have done his research (we would hope). The focal length can be somewhat mitigated with the focal reducer to bring it down to F7.7- not fast but sufficient to be attractive at a more manageable less than 3 metres. What it does have, at least in the Edge variant, is a very nice flat field enough to cover an APSC sized chip and the all important image scale- there are very few fuzzies that wont fit on the CCD even at that focal length.

I think it's all about doing the research then choosing an telescope that measures up to your findings & using your gut feeling "....is this right for me?.....". Aperture is king when you seek the fuzzies of the Universe.....not so for planetary imaging where considerations of seeing play a substantial part.

[pyrasanth]

9 minutes ago, Stu said:

Well.... cool down is rarely an issue for scopes kept out doors???? Ability to keep up with falling temperatures during a night's observing/imaging is probably more important in your case, but the OP was not discussing this as permanently mounted as far as I'm aware?

A telescope out of doors if covered with the wrong type of cover can have greater cool down issues than a telescope kept in doors. Mitigated more in an observatory but both environments- under a cover or in an observatory "green House" can be very bad so it's all down to the circumstances of storage. My telescope is out of doors but the cover has an internal thermal shield so the scope even with the hot sun stays very cool- but under a standard cover it would probably melt.

It does not matter if the discussion goes on a bit of a tangent- it's all good discussion material.

[ollypenrice]

34 minutes ago, pyrasanth said:

The C14 is a big instrument & not a cheap investment either when you consider the mounting requirements to get the best from it- it is simply enormous when compared with the average back garden telescope & thus the savvy astronomer would have done his research (we would hope). The focal length can be somewhat mitigated with the focal reducer to bring it down to F7.7- not fast but sufficient to be attractive at a more manageable less than 3 metres. What it does have, at least in the Edge variant, is a very nice flat field enough to cover an APSC sized chip and the all important image scale- there are very few fuzzies that wont fit on the CCD even at that focal length.

I think it's all about doing the research then choosing an telescope that measures up to your findings & using your gut feeling "....is this right for me?.....". Aperture is king when you seek the fuzzies of the Universe.....not so for planetary imaging where considerations of seeing play a substantial part.

The focal reducer doesn't bring any visual benefit. It won't widen the FOV if using 2 inch visual back. The baffle tube sets the limit.

For DS imaging it's also a mixed blessing. It seems that it won't cover full frame CCD chips (44mm isn't enough for the big Kodak). Maybe working at native FL is the way. I aim to give it a go with a smaller flat field SCT.

Olly