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I'm interested in astrophotography using a C14.? I would need to transport the C14 though as my condominium lacks a suitable setup location.? Due to portability requirements, I was leaning towards the C11 but I've heard rumors that the C14 is, in fact, a small scope...
So with this in mind - portable astrophotography using the C14 - I've got quite a few questions I've compiled after doing some Internet research on the topic.? Any advice/opinions on the following questions are much appreciated.
1) Mount - Is the ASA DDM60pro really suitable for C14 astrophotography or would I be much better off with an AP 1100GTO?? Dale Liebenberg? - ?- uses the ASA DDM60pro and seems to achieve good results... but the 28kg maximum payload for the DDM60pro worries me.? Moreover, Dale's C14 is housed in a remote observatory and thus is somewhat shielded from wind.? To the extent that a DDM60pro is sensitive to wind under high loads, my field setup would obviously be much more prone to wind-induced instability. 2) Corrector Plate Reflection Halo - Dennis di Cicco's review of the C14 in the February 2011 issue of Sky and Telescope noted that bright stars sometimes cause halos due to reflection off the corrector plate.? An example of this is shown here: However, the only mention I could find about?corrector plate reflection halos is the S&T review.? In practice, are reflection halos an issue to be concerned about? 3) Celestron's EdgeHD Reducer - I've read that the EdgeHD reducer is somewhat difficult to use.? What are the issues associated with the reducer? 4) Cooling - For portable use, are?cooling fans (e.g., TEMP-est) necessary?? If installing TEMP-est fans onto a C14 EdgeHD, is any drilling of the OTA required?? 5) OAG and Guide Stars - How difficult is it to find a guide star using an OAG at f/11?? I was thinking that Innovations Foresight's ONAG (http://www.innovationsforesight.com/) might be a better solution.? Does anyone have experience with the ONAG?
Thanks in advance for any feedback.
Dave
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I have an observatory-mounted C14HD on a CGE-PRO?mount.? Have you ever seen this beast?? It is much larger and heavier than you think.??Unless you are a body builder, I don't recommend this set-up as a transportable imaging platform.? It is huge, awkward, and very heavy.??However, image quality is superb. ? The CGE-PRO is at it's limit with this scope and is only marginally steady enough for AP.? Look at Astro-Physics or Paramount mounts. ? I have never seen a corrector plate halo.? It is coated so well that I can barely see it. ? The Edge reducer is very heavy and positioning is essential at 146mm behind the?rear of the scope.? Otherwise, no problem. ? Temp-est fans are essential.? No drilling required.? Very easy to install.? I use dew heaters and a dew shield -- essential in my climate. ? Suggest a small 80mm light-weight refractor for guiding. ? I would emphasize that this is a big, long focal-length scope, and AP with it will not be easy.??Unless you have lots of prior experience, think in terms of smaller, shorter fl, more easily transportable. scopes. ? Clear skies.?? Lou ?
To: C14_EdgeHD@... From: dhank1ns@... Date: Fri, 21 Feb 2014 01:14:44 -0800 Subject: [C14_EdgeHD] A Plethora of Questions Regarding C14 Astrophotography
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I'm interested in astrophotography using a C14.? I would need to transport the C14 though as my condominium lacks a suitable setup location.? Due to portability requirements, I was leaning towards the C11 but I've heard rumors that the C14 is, in fact, a small scope...
So with this in mind - portable astrophotography using the C14 - I've got quite a few questions I've compiled after doing some Internet research on the topic.? Any advice/opinions on the following questions are much appreciated.
1) Mount - Is the ASA DDM60pro really suitable for C14 astrophotography or would I be much better off with an AP 1100GTO?? Dale Liebenberg? - ?- uses the ASA DDM60pro and seems to achieve good results... but the 28kg maximum payload for the DDM60pro worries me.? Moreover, Dale's C14 is housed in a remote observatory and thus is somewhat shielded from wind.? To the extent that a DDM60pro is sensitive to wind under high loads, my field setup would obviously be much more prone to wind-induced instability.
2) Corrector Plate Reflection Halo - Dennis di Cicco's review of the C14 in the February 2011 issue of Sky and Telescope noted that bright stars sometimes cause halos due to reflection off the corrector plate.? An example of this is shown here:
However, the only mention I could find about?corrector plate reflection halos is the S&T review.? In practice, are reflection halos an issue to be concerned about?
3) Celestron's EdgeHD Reducer - I've read that the EdgeHD reducer is somewhat difficult to use.? What are the issues associated with the reducer?
4) Cooling - For portable use, are?cooling fans (e.g., TEMP-est) necessary?? If installing TEMP-est fans onto a C14 EdgeHD, is any drilling of the OTA required??
5) OAG and Guide Stars - How difficult is it to find a guide star using an OAG at f/11?? I was thinking that Innovations Foresight's ONAG (http://www.innovationsforesight.com/) might be a better solution.? Does anyone have experience with the ONAG?
Thanks in advance for any feedback.
Dave
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Thanks Lou. >>? Have you ever seen this beast?? It is much larger and heavier than you think.??Unless you are a body builder, I don't recommend this set-up as a transportable Yes, I'm aware of its size.? But there are those who transport this instrument.? And besides, it's a small scope :-)
Prior to watching the above video, I had completely ruled out transporting a C14.? But having watched the video, I think it's worth some consideration, though in the end, I may go with the C11.
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I own a C14 on an AP1100. Both are in theory portable, but frankly I would only take them into the boonies if it is for more than one night. For more casual portability I would suggest a C11 on a lighter mount (AP900 or a Mach1?) ?as far more likely to be carried around. For DSO imaging I would strongly suggest a Hyperstar, since this ought to enable unguided imaging with subs under a minute each. Get a camera with tiny pixels and you end up with an image scale not too far from the average seeing limit. Using a modded Canon DSLR makes the imaging almost snapshooting, no long cables anywhere, no PC, no bulky batteries. OK, I exaggerate a bit, but you get the "drift". While the Hyperstar ought to keep any beginner at DSO imaging happy for at least 5 years, the C11 Edge HD really ought to be used with its custom-design reducer, at the exact distance specified by Celestron. Anything else is a compromise on what is a fine instrument. Make sure your OAG can be used without messing up the desired back focus distances, both at f11 and at the reduced focal ratio. Reflection halos from bright stars. I suspect that such comments apply to imaging with the Hyperstar at f2, not at the longer focal ratios. At f2 we just have to put up with this nuisance by avoiding bright stars in or very close to the FoV. If your condo has a flat roof, that Hyperstar will be fun.
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Dave, With respect if you are just starting to learn astrophotography you need to simplify your setup significantly. Here are a few suggestions in no particular order. a. The most important component is the mount. I have an AP Mach1 that works great with a C-11 as well as my little 110mm refractor. In fact is easier to get excellent results with the low weight refractor and is especially easier to select suitable guide stars with my ST-4000 XCM camera (which does not break the bank and eliminates the need for a separate guide scope). b. I can barely handle the C-11. As stated in other replies the C-14 is a beast. c. If you think you need a focal reducer for your objects of interest?get a shorter fl scope instead. d. Greatly simplify your camera/guiding setup. A dedicated guide scope is good but it is also another component to setup/align every time. e. Take the time to research and?study the software you will need. The learning curve is steep.
regards, Ron K
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Thanks all.
A little more information to help guide the discussion: 1. I'm not interested in beginning astrophotography.? Sorry if I gave?this impression. 2. Although I may eventually be interested in the Hyperstar configuration, at present my interest is imaging at native f/11 or at f/7.7 with the reducer. 3. I anticipate extreme difficulty guiding the C14.? I really don't think I can get away with a guide scope.? Hence my interest in the ONAG. 4. The "halos" I'm specifically interested in knowing about are those that Dennis di Cicco reported as originating from the EdgeHD corrector plate.? The only mention that I've read of halos originating off the corrector plate is the S&T review... so perhaps this is a non-issue.? But if you've heard about such halos or have personally encountered them I'd like to know about it. 5. I will be using a large chip CCD - perhaps the KAF-16803 but likely an interline such as the KAI-11002 or similar ilk. 6. And sadly, my condominium is such that any onsite observing is literally impossible - no space/deck/roof? on my condo, no balcony, lots of tall trees in the surrounding common grounds and bright lights everywhere.? So it is likely that I'll be making multi-day trips out to eastern Washington (I live near Seattle, Washington) to take images. 7. And thanks for the multiple warnings about the C14 weight - yes it's huge (bulky) and heavy (48 lbs).? So my initial impression is that it's crazy to haul that scope around.? But a few brave souls do so and, honestly, lifting the C14 onto its mount is what scares me the most.? These fears have been allayed by Greg Nowell's excellent - and humorous - video.? And besides... if the bulk of my imaging is going to come from multi-day trips, the additional inconvenience of the C14 over the C11 becomes less of an issue for me.? But I still haven't made up my mind on this and am leaning towards the C11.
Dave
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Have a meeting I need to get to but just a few comments from one who started out using a C14 for astro photos.
Number one.... If you can, get the absolute best mount you ever think you're going to need..... ever! ?Pay the bucks, do it right, will save you in the end.
Second make sure your scope is faststar ready and buy a Hyperstar for it from Starizona. ?it makes getting into astro photography a snap ( well lots easier than trying to image at 3000+mm.... even with a reducer F7 ?requires much longer exposures than f2 with a hyperstar.
Do that and you'll start out having fun and getting some very good stuff vs being very very frustrated. ?You'll be getting great pictures while learning the ropes.
Have to run, but that's my 2 cents.
Al
Al Acker
On Fri, Feb 21, 2014 at 2:14 AM, <dhank1ns@...> wrote:
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I'm interested in astrophotography using a C14.? I would need to transport the C14 though as my condominium lacks a suitable setup location.? Due to portability requirements, I was leaning towards the C11 but I've heard rumors that the C14 is, in fact, a small scope...
So with this in mind - portable astrophotography using the C14 - I've got quite a few questions I've compiled after doing some Internet research on the topic.? Any advice/opinions on the following questions are much appreciated.
1) Mount - Is the ASA DDM60pro really suitable for C14 astrophotography or would I be much better off with an AP 1100GTO?? Dale Liebenberg? - ?- uses the ASA DDM60pro and seems to achieve good results... but the 28kg maximum payload for the DDM60pro worries me.? Moreover, Dale's C14 is housed in a remote observatory and thus is somewhat shielded from wind.? To the extent that a DDM60pro is sensitive to wind under high loads, my field setup would obviously be much more prone to wind-induced instability.
2) Corrector Plate Reflection Halo - Dennis di Cicco's review of the C14 in the February 2011 issue of Sky and Telescope noted that bright stars sometimes cause halos due to reflection off the corrector plate.? An example of this is shown here:
However, the only mention I could find about?corrector plate reflection halos is the S&T review.? In practice, are reflection halos an issue to be concerned about? 3) Celestron's EdgeHD Reducer - I've read that the EdgeHD reducer is somewhat difficult to use.? What are the issues associated with the reducer?
4) Cooling - For portable use, are?cooling fans (e.g., TEMP-est) necessary?? If installing TEMP-est fans onto a C14 EdgeHD, is any drilling of the OTA required?? 5) OAG and Guide Stars - How difficult is it to find a guide star using an OAG at f/11?? I was thinking that Innovations Foresight's ONAG () might be a better solution.? Does anyone have experience with the ONAG?
Thanks in advance for any feedback.
Dave
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Dave, Sorry but it did sound like you were looking at just starting.
For your multi-day field setup you may be interested in a Telegizmos cover. I have used one for my C-11/Mach1 for continuous months over a three year period of time with no issues.
I am curious as to why you believe that the C-14 will be difficult to guide?
regards, Ron K.
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>> I own a C14 on an AP1100. Both are in theory portable, but frankly I would only take them into the boonies if it is for more than one night.
Agree. ?For my portable setup, I have all the computers etc in a small utility trailer and set up a 10x10 EMT box that I use as a ?"tent". ?The EMP supports tarps on the sides ( for walls ) and can cover the scope in the daytime. ?My C14 sits on a MEII mount and I would NOT want to set this all up for a single night of viewing. ??
Al
Al Acker
On Fri, Feb 21, 2014 at 5:46 AM, <samirkharusi@...> wrote:
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I own a C14 on an AP1100. Both are in theory portable, but frankly I would only take them into the boonies if it is for more than one night. For more casual portability I would suggest a C11 on a lighter mount (AP900 or a Mach1?) ?as far more likely to be carried around. For DSO imaging I would strongly suggest a Hyperstar, since this ought to enable unguided imaging with subs under a minute each. Get a camera with tiny pixels and you end up with an image scale not too far from the average seeing limit. Using a modded Canon DSLR makes the imaging almost snapshooting, no long cables anywhere, no PC, no bulky batteries. OK, I exaggerate a bit, but you get the "drift". While the Hyperstar ought to keep any beginner at DSO imaging happy for at least 5 years, the C11 Edge HD really ought to be used with its custom-design reducer, at the exact distance specified by Celestron. Anything else is a compromise on what is a fine instrument. Make sure your OAG can be used without messing up the desired back focus distances, both at f11 and at the reduced focal ratio. Reflection halos from bright stars. I suspect that such comments apply to imaging with the Hyperstar at f2, not at the longer focal ratios. At f2 we just have to put up with this nuisance by avoiding bright stars in or very close to the FoV. If your condo has a flat roof, that Hyperstar will be fun.
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"rumors that the C14 is, in fact, a small scope"
"1) ASA DDM60pro?.. or?... AP 1100GTO" Probably doesn't make that much difference. I recommend AP because of long experience but I can't really?judge?ASA.? It adds significant cost (maybe for future upgrade?) but the AP1100 hi-res encoder/tracking system is amazing.
"2) Corrector Plate Reflection Halo" I don't buy it. It is difficult to imagine an optical path that would bring in a significant correlated reflection from the corrector.? The artifact in that image looks much more like a reflection from a reducer or corrector or filter or other element near the camera.? In any event, that star is impossibly bright and atypical of 99% of the target fields?for C-14.
"3) Celestron's EdgeHD Reducer..." There are numerous reports of difficulty with the reducer.?If you plan to chronically reduce then also consider a classical SCT with the Celestron 0.63x reducer/corrector or Starizona 0.5x (see the Starizona site for ray traces of those options).
"4) Cooling" For high-res (prime FL or Barlow)?get a cooling system (not so important for reduced imaging). There are several different ones.? I forget the name or web page but a member of this forum did a robust study of this issue (maybe he'll chime in here).
"5) OAG and Guide Stars..." Part of that equation is the FOV and sensitivity of the guide camera (e.g. ZWO ASA120MM is very sensitive but small).? The key to OAG is pre-planning the rotation and offsets via "The Sky" (or similar).
Stan
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Hi Dave, Yes, the C14 is quite heavy for the DDM60. But I did manage to trim down, replacing the heavy STL with a FLI ML and getting rid of my rotator. But the wind is still a factor with the large wind area of the OTA and quite a bit of flexure in my pier. Adding on the dome has also helped. I'm not sure if a solid tripod as you will be using will eliminate the flexure caused by wind. In theory, the DDM with motor drive and sensitive encoders should respond well and counteract the effects of?wind gusts. Dale
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Yes, I agree with the wind problem for a C14... well any scope for that matter but the bigger OTAs really catch it. ?That's why I have my "tent" setup when I go portable... I think there are some shots of it up on my astro photo site. ? if anyone is interested.
Al
Al Acker
A
On Sat, Feb 22, 2014 at 10:02 AM, <dale.liebenberg@...> wrote:
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Hi Dave, Yes, the C14 is quite heavy for the DDM60. But I did manage to trim down, replacing the heavy STL with a FLI ML and getting rid of my rotator. But the wind is still a factor with the large wind area of the OTA and quite a bit of flexure in my pier. Adding on the dome has also helped. I'm not sure if a solid tripod as you will be using will eliminate the flexure caused by wind. In theory, the DDM with motor drive and sensitive encoders should respond well and counteract the effects of?wind gusts.
Dale
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Lou Halikman