Thoughts on a change of kit

[eifionglyn]

So. When I first got into astronomy a few years ago, the advice from everyone was , get a Dob, get a Dob. But I didn't fancy a Dob, I fancied an equatorial mount so that's what I got. I didn't like the thought of nudging the scope to keep up with the object, so I got a 200p on an EQ5 and added the RA/Dec motors later.

Now was very happy with this setup for a while, but it does take a while to set up from where I have it stored, past my furniture, into the garden, at least 4 trips counting mount, tube, counterweights and accessories, more trips if I want to take out a sky atlas, or a glass of wine. And with each trip opening the patio door earns a disapproving look from the other half as I let more cold air into the house.

To make the most of short breaks in clouds, and to preserve domestic harmony I got myself a Heritage 130, very happy with it, it's great optically, can be carried in one hand, so quick to set up, and having used it, you know what? It's not so bad nudging the Dob mount to keep up with the stupid planet rotating inconveniently under my feet. Not so bad at all in fact, it's got me thinking. See I always thought I'd done well with the EQ5, being an EQ mount I could use it for astrophotography, however, having tried it, and read up a bit, the standard EQ5 doesn't really cut it. It's a good equatorial mount for visual use, but for AP, in all honesty doesn't cut the mustard. Not with a 200p, a DSLR and someday a guidescope mounted.

So, I figure I can go one of two ways from here. I can sell the 200p OTA, get a smaller lighter OTA for AP, say a Mak 127, or a short tube refractor, which will not overtax the EQ5. Or, I can sell the 200p and the EQ5, and get a larger Dob, probably the 250 or maybe even the 300, enjoy the large aperture visual observing, while saving up for a couple of years to get a HEQ5 or EQ6 if I still feel the need for imaging.

Wondered if anyone had any thoughts. Also how do the solid vs flex-tube dobs compare in terms of ease of carrying, setup etc. If I go for 12" then it will definitely be a flex tube, but the 10" is available as a flex and solid.

[ronin]

One aspect is the 200P is a longer focal length then the 130P so you will get greater magnifications, this means smaller fields of view so more frequent nudging to keep anything in view.

From what is seen most people carry the dobsonians out in 2 goes not one, someone I know with an 8" takes 3 trips from their car to get all the sections. Wine and Sky atlas will still need seperate trips as with the EQ. What alters most is the weight that you haul round, and the setting up.

If you want to try AP before the EQ6 route get a small ED refractor for the EQ5 say 70mm ish.

[Naemeth]

It's 3 trips for my 10" dob. One for the OTA, one for the mount, one for my eyepieces and star atlas. Very easy to move down stairs, quite light (13kg OTA, 15kg base) and great views. Plus set-up time is about the 30 seconds it takes to put the OTA on the mount.

Unless you cannot store / transport a 1.2m tube, don't bother with the flextube, it's more expensive and is actually heavier than the solid tube.

[eifionglyn]

Unless you cannot store / transport a 1.2m tube, don't bother with the flextube, it's more expensive and is actually heavier than the solid tube.

I hadn't considered that, but thinking about it for a minute it's obvious. The flextube packs the sufficient rigidity into less structure, so clearly it's going to have to be heavier to do the job. Maybe the 10 inch solid tube Dob is the way to go...

[Charic]

eifionglyn.......

Not sure the Dobsonian mounted newtonians are the best way forward for astrophotography. I like your self went for a 200mm 8" and really happy with it so-far, but I  just make out M31, Its there, but not Wow! can also see M110 next to it,  ( Light pollution at my site -  I can read my books at night, so really need a better dark place to  better test ) but not sure I`ll get much better than I already have, At least I can see the Galaxy.

You asked for thoughts. I`m seeing some truly spectacular images of M31 from people using refractors in the 70 - 100mm range. That might be my next choice, although I initialy thought I should be  buying  a Catadioptric?
Whether you sell or purchase another telescope is going to give you `astronitus- sleepless nights` till you come to your decsion. As for carrying Dobs, because of their design and position of the tension handles (Sky-watcher Skyliner) the assembly becomes taller whilst carrying, so height restrictions and or weight of the assembly require attention, so watch out when going through doorways, or out of sheds. Ive not had the experience yet, but aware of the outcome. you mention flex tubes. Not ever owing one, FLEX does`nt inspire any good thoughts. Does it require fresh collimation everytime its extended, is the locking system so good, that  collimation is not required, and images of flextubes without jackets!..........surely a route for stray light to enter from all angles? Might be wrong. still learning myself.
 

[Luke]

My thoughts are leave the imaging for now and have a ball doing visual. Imaging can really suck up your time and cut down on how much observing you do, especially if you do not have an observatory to ease the setup. If you spend an hour or so setting up (sometimes it took me up to two hours to get going with my most complex imaging setup) it can dampen your drive to observe, and if you keep looking at the laptop screen that probably doesn't help with night vision.

Re: flextube versus solid tube, I prefer solid tube if the scope is for home only. My solid tube dobs have been more resistant to dew, hardly ever need to be collimated - I check about every six months (I had to collimate my flextubes every time, though some people find they do not need to do this - not a big deal to collimate, it takes me about two minutes), do not need a light shroud, and of course do not need to be extended.

Flextubes are fantastic scopes and are really not much hassle at all, but I love having an easy to move dob that is as low on hassle as possible while having a large aperture. It gets a ton of use as there is so little time investment to pop it out and get it ready to use.

I find the 12 Skywatcher's a little bit of a heft to move while my 10 inch GSO dob feels pretty effortless (I carry it out in two goes - base on its own, then tube).

The 12 is not that difficult to move, I am just a very lazy observer at times and I like next to no effort to get me to put the scope out on nights when it might not clear later or be clear for long.

Another thought - could you store a dob in a shed outside? The dob would then already be cooled down and of course it would cut down your trips in and out of the house.

[eifionglyn]

Yes I know that Dobs are not the way to go for AP. What I'm thinking is that nothing on a standard eq5 is going to be that good for AP so until I've got the money to sink into an EQ6 I might as well enjoy the quick and simple setup offered by a Dob. Why am I spending ask the time and effort carrying all the gear out and doing a polar alignment when the mount isn't going to track that well no matter what you do. Or its it me not running the mount well enough.

I have considered a small refractor on the EQ5 for AP but not sure if it's worth it until I have a really sturdy mount available that will take the wrought of a guider, camera and the imaging scope.

Sent from my Nexus 4 using Tapatalk now Free

[eifionglyn]

Thanks for the insight Luke, I'm leaning towards switching to a 10" Dob and leaving AP until I've got the money and time to do it properly. I know it's possible with the EQ5 after a fashion, but at the moment I'm spending a clear evening imaging and just not getting results I'm happy with - and as you say missing out on visual observation. I too am also a lazy astronomer, and the one thing I love about my Heritage is it takes absolutely no time to set up. I like the idea of getting almost the same convenience with twice the aperture. On a clear evening I can take the base and the tube out in two goes fairly early on before it gets too cold to be opening doors, set the thing up and let it cool down while I have dinner, ready to observe later. No polar aligning, no extension lead to trip over, power supply to connect up.

One thing that still has me uncertain about switching is that when I added the motors to my mount I found an immediate improvement in the views, just by having the mount track in RA without my touching it rather than using the slow motion controls, which however smooth you try to be always induced some vibration in the mount. Wondering how this would be on a 250mm Dob, it's not so bad on the 130, but will it be worse on the bigger scope with the longer focal length?

[jnb]

My thoughts, if you're likely to want to try AP in future then stick with the equatorial or you'll just be swapping equipment back and forth. I would suggest getting a shed, doesn't need to be large but if you can store a lot of the kit there then you can set up much more easily without upsetting domestic harmony and the cost of a shed is probably less then the cost of swapping all that kit around plus if you do start AP and can't find space for an observatory then the scope can be set up outside with power laid into the shed which then becomes a warm room for those long sessions.

of course this presumes that there's not some pressing reason why you can't build a shed.

[RikM]

Thanks for the insight Luke, I'm leaning towards switching to a 10" Dob and leaving AP until I've got the money and time to do it properly. I know it's possible with the EQ5 after a fashion, but at the moment I'm spending a clear evening imaging and just not getting results I'm happy with - and as you say missing out on visual observation. I too am also a lazy astronomer, and the one thing I love about my Heritage is it takes absolutely no time to set up. I like the idea of getting almost the same convenience with twice the aperture. On a clear evening I can take the base and the tube out in two goes fairly early on before it gets too cold to be opening doors, set the thing up and let it cool down while I have dinner, ready to observe later. No polar aligning, no extension lead to trip over, power supply to connect up.

One thing that still has me uncertain about switching is that when I added the motors to my mount I found an immediate improvement in the views, just by having the mount track in RA without my touching it rather than using the slow motion controls, which however smooth you try to be always induced some vibration in the mount. Wondering how this would be on a 250mm Dob, it's not so bad on the 130, but will it be worse on the bigger scope with the longer focal length?

I have a solid tube 250PX Dob for visual use and love it. I usually make two trips from the garage to the garden, telescope+base fully assembled with a foam dewshield on the end and then a second trip for EP case and observing stool. My copy of S&T pocket sky atlas lives in my EP case. Carrying the full telescope, I do have to be careful negotiating the garage door, but it's not a big deal if you are fit and capable of lifting it safely. It fits in car easily for trips out to the country as well. 

I find larger dobs are actually 'easier' to use than the smaller ones. They move more smoothly and don't vibrate as much due to the larger mass. For the equivalent magnification, the extra focal length is fairly irrelevant. 150x is 150x it just means you can use a longer FL EP to achieve it in the larger scope, which (depending on EP design) might mean a more comfortable experience. I do use 70­° aFOV eyepieces though, which gives more time for the object to pass through between nudges, but I don't find it any bother to track things even at ludicrous power sometimes (430x is my max available but very seldom useful!).

[Scott]

I think you've been very wise to view ap and visual as two separate fields of astronomy. Just wondering how handy you are with wood work? Is it possible you could build a base for your 200p? that way, if you ever felt the need to mount it on the eq the option is there. you've probably done it, but turn your motors off to give you an idea of how fast things move across the fov of your 200p.

Hope this is of some help

Scott

[Naemeth]

One thing to note with smaller dobs that the eyepiece is often quite near to the ground. An observing stool or seat is always a good idea .

[eifionglyn]

I know what you mean jnb, swapping equipment back and forth is costly as you never get back what you paid when selling stuff on, even if it is in perfect condition, as buyers of 2nd hand stuff expect a reasonable drop in price over new. And I will want to try AP in the future. It's why I got the EQ5 mount in the first place, its just what I've realised now is that for AP I'm going to have to upgrade from the standard EQ5 anyway, and I'm not in a position to do that at the moment. Ideally I'd like a permanently mounted pillar in the garden, which can have a sundial or birdbath on it during the day, which can then be removed to reveal the attachment points for an EQ mount. They say the scope that shows you most is the one you use the most, at the moment I look at my EQ5, tripod, rings, weights, power cables, just can't be bothered with it and take out the Heritage instead, especially if the forecast is marginal. As such the 200p / EQ5 setup is getting less and less use.

A shed would be mightily useful, however my garden is problematic when it comes to sheds. Or any kind of serious hard landscaping really. As a small, suburban garden in a mid-terrace, I have no access to the garden other than through the house, which means everything for the base, any sand, cement, gravel or slabs have to come through the house - not to mention the shed itself. Then all the spoil from excavating for the base has to come back through the house and away to somewhere. Adding anything larger than a potted shrub to my back garden is quite an undertaking. Additionally the ideal space for a shed is currently taken up by 6 tree stumps of some leylandii I cut down 7 years ago which have so far resisted all my attempts at removal including axes, chainsaws and splitting wedges. My two log splitting wedges are currently embedded and stuck in the largest stump. I have thought about getting one of those plastic chest style garden storage units but concerned about how dry they'd be for keeping astronomical instruments in them.

Having said all that with the way the weather's been lately I'll settle for 5 minutes looking at the moon through bins!

[bingevader]

I think you've been very wise to view ap and visual as two separate fields of astronomy. Just wondering how handy you are with wood work? Is it possible you could build a base for your 200p? that way, if you ever felt the need to mount it on the eq the option is there. you've probably done it, but turn your motors off to give you an idea of how fast things move across the fov of your 200p.

Hope this is of some help

Scott

I wondered the same myself! It wouldn't be an expensive mod and would allow you to see for yourself before investing in a bigger dob or saving for the new mount or AP 'scope.

Cheers

[eifionglyn]

Starting to think of a different idea now. Talk of sheds is getting me thinking. Does anyone have any experience of storing telescopes and mounts long term in a plastic garden tool store thingy? Thinking one of these type of things?

http://www.ebay.co.uk/itm/KETER-STORE-IT-OUT-XL-IN-BROWN-PLASTIC-GARDEN-SHED-WHEELIE-BIN-STORAGE-/180916580513?pt=LH_DefaultDomain_3&hash=item2a1f77f0a1

It would be against the house wall on one side and a 6 foot fence on another so hopefully sheltered from the worst of the weather. I know it says that it keeps things dry, just wondering if "dry" for the purposes of garden tools and BBQs is the same "dry" as we need for astronomical instruments.

[eifionglyn]

Right been thinking even more (hard work this thinking lark) The 200p / EQ5 setup is on fleabay and under a reasonable offer, so I need to start making decisions. I've tried to list them rationally but find that writing stuff down just makes me think of even more options and factors and considerations. Couple of days ago I was 99% sold on the 10-inch Dob and forget AP for the time being. Now, I'm not sure at all. AP will be a minor interest for me, can't see me ever getting into cooled CCDs and hours upon hours of exposures, but I would like to be able to webcam a planet, do prime focus DSLR imaging, or even piggy-back a camera for wide field constellation / milky way images, and that means an EQ - driven, (guided?) with all the attendant weight and hassle and setup issues I'm trying to avoid in the first place arrrggghhh, it seems the more I think about it the more I drive myself round in circles!

1. Skyliner 250, RACI, Rigel - £535

Forget AP for now, start a fund for HEQ5. 

Pros - More aperture, quick setup. Within Budget

Cons - Will I miss RA tracking for visual?

 

2. Skyliner 200, RACI, Rigel - £380

Forget AP for now, £100 to kick start fund for HEQ5 or 2x Explorer BSTs

Pros - I know I can move / store an 8", more eyepieces, quick setup

Cons - same OTA as now so why change? - Will I miss RA tracking

 

3. Keep existing setup, persevere with EQ5 for visual (OK) put up with its shortcomings for unguided AP, sort out garden storage, DYI build Dob mount.

Pros - no immediate spend. £230 to spend on garden storage / Dob mount build. Keep RA tracking when I can be bothered to set up EQ5, develop AP skills, better alignment, balancing, shorter exposures.

Cons - High probability of screwing up Dob build, wasting materials. Flogging dead horse with EQ5 carrying 200p + DSLR. Need to budget for new focuser at least.

 

4. Keep EQ5, sell 200p get lighter short tube refractor for AP, start fund to upgrade EQ5 with Synscan to allow guiding.

Pros - Always fancied refractor, EQ5 might perform better with less weight.

Cons - 200p OTA only won't sell well, unknown budget, putting more money into EQ5 might not be good idea - dead horse?, no medium-large aperture scope available for visual use

What's the minimum I need in terms of a mount to be able to reliably take say 30 second subs without trailing on a DSLR? Can it be done with anything less than a HEQ5 guided or equivalent? If the answer's no, then I know there's no point me persevering with my EQ5, and I just have the choice of 8 or 10 inch Dob.

[Naemeth]

Option 1 is the best, although 3 definitely has it's merits. A dob mount shouldn't be too difficult to make for the 200P, and there are plenty on here who have excellent wordworking skills (Moonshane, swamp_thing to name a few).

The minimum you want is the HEQ-5, while mounts like the EQ3-2 and EQ5 can do, they are much more comfortable with just a camera. There have been plenty of members who have successfully imaged with an EQ-5, but you have to throw a lot more subs away than you would with a HEQ-5. I honestly think the ED80 / HEQ-5 combo is so popular because it just works. Doesn't tax the mount or the operator.

[RikM]

Best 1 hours worth of 90sec unguided subs from 4 hours taken. Canon 1000D with a remote shutter release on 150P + EQ3-2 with the dual axis motors. Normal aluminium tripod, no modifications, no polar scope.

You can do it, it just takes extra effort and you have to be realistic about the targets you go for and the quality you can achieve.

With an HEQ5 and more important an autoguider, you will have a much easier time of it. More stable so less subs lost to the wind = shorter actual time and less noise, plus longer subs available so more detail in the faint areas, sharper stars etc. just better all round.

[Stargazer_00]

quality picture from a 150p.

On the OP, I'd say sell up and get a 200p or a 300p.  The 250px is much more demanding on eyepieces than either of these scopes.

I hada  250px and it was a really good, easy to set up scope.  My scopes are stored in a shed in the garden though so setup time for any size is the same.  This is why I got a 350p, it's the most I can manage on my own.  Takes the same setup time as my old 250px, less than 5 minutes(including collimation).  Pretty much bang on ambient temperature as well as it's stored outdoors.

[AlexB67]

I hadn't considered that, but thinking about it for a minute it's obvious. The flextube packs the sufficient rigidity into less structure, so clearly it's going to have to be heavier to do the job. Maybe the 10 inch solid tube Dob is the way to go...

I would only buy a flextube if transport is an issue or perhaps because it fits somewhere in a magic corner where a solid tube would not fit and that matters to you. I bought one because of the former, it is an ideal fit for the car.  In the end the flextube OTA weighs about 3 - 4 kg heavier also and it needs a light shroud that will cost extra, but can be cheap if home made. That being said, it is very easy to pick up the OTA because it has a rim around it where the truss tubes go through. I find this provides an ideal way to pick them up and you have nothing obstructing your face going through doors, you can see where you are going.  They are heavier, but the 10 inch OTA is surprisingly easy to carry. To put it in perspective, I find the mount more awkward to get through the doors.

[eifionglyn]

On the OP, I'd say sell up and get a 200p or a 300p.  The 250px is much more demanding on eyepieces than either of these scopes.

Can you give more information on that?

I understand it's something to do with fast scopes being harder on lower quality eyepieces. Would something like a BST Explorer suffer too badly from it? I have the 18mm and intend to buy more to replace the 10 and 25 skywatcher ones I have.

The Explorer 200 I have is F5, which is pretty fast, I've never noticed the images suffering terribly, then I've not got much to compare it to, being the only "real" scope I've spent serious time with. When you say they are demanding on eyepieces what would that actually look like compared to a less demanding scope. The current 200mm Dob is f/5.9, while the 250 is f/4.7 so not that much faster than what I'm used to. The 300 is only available as a flex-tube, and I think is over budget in terms of money and space / handling.

However, am prepared to be persuaded if collective wisdom and experience says I'll see more out of the 8-inch with average eyepieces than the 10-inch, though there's always the fear of the nagging feeling of looking through the 8 and wishing you'd got the 10.

As for my options 3 and 4 above, they've been taken away as the scope has sold for the asking price and is being collected tonight, so I have a budget of around £550 that needs spending on telescopes before I waste it on such trivialities as rent and food.

[eifionglyn]

Went for the 10-inch Dob, Rigel Quick Finder and the 9x50 RACI finderscope.

Now begins the waiting for the postman game!

[Naemeth]

Good choice .