Bukko

On 26/10/2021 at 20:17, Andrew INT said:

I've had my eye on the 3m scopedome for several years now. When the v3 came out, I was determined to take the plunge. Base and pier built in anticipation of the new arrival and then, somewhat out of the blue came Covid, furlough and redundancy.

Thankfully I'm back in work again and looking to relocate from a Bortle 4 to somewhere darker. Fingers crossed my some will become reality at some point.

In the mean time, I have thoroughly enjoyed reading Gordon's adventures in France.  I shall make copious notes for future reference!

May I ask why you decided to raise the domes? Was is predominantly to create space of equipment under the flooring or for other reasons (such as ventilation?

Thanks once again for such a terrific thread

Andrew

 

Hello Andrew,

I am pleased you have enjoyed my post.

There was several reasons to elevate the domes. I wanted to get further off the ground, to reduce the effects of moisture, etc. rising from it. It also gave me space to house equipment like a UPS, cabling and a computer. There is a small ventilation fan on a changeover switch with a dehumidifier. The fan is below the internal floor, the dehumidifier sits on top.  I also thought it would add some security, as any would-be thief would have to deal with the height. As the whole dome rotates, I could not build any fixed steps and I know from experience, it is a real pain to swap out equipment. I wanted to make them somewhat higher, but was limited by planning consent and I did not have eenough pipe to make the piers any higher. One wall is 50cm high and the other 80cm. The height was simply governed by the size of the bricks.

I have a 12" Newt in one dome and it takes up a surprisingly large amount of space. tracking objects low in the sky leaves me having to crawl under it. I have thought about reducing the internal floor height to make this easier, but right now, it works fine for visual too.

The domes are quite exposed and I suffer from wind. (no sniggering, please) It took the roof off my warm room and to protect the domes, I drilled the concrete base and installed 8 lengths of studbar connected to the fixed ring of each dome.

My original NEQ6 got very tired and worn out. It was replaced a year or more ago with a CEM70.  More recently, we had a lighting strike close by. It damaged a camera and one of the PC's. Both needed replacing. Unexpected upgrades and now I am looking at having to install a decent grounding system....

Heres hoping you get to build your dream system sometime soon.

Gordon.

The plate does look like an exquisite piece of engineering and a $500 price tag for small prioduction run seems more than reasonable for the design and work carried out.

However.

To hold an AVX mount, the plate is so over-engineered and the cost to do such a basic task is ridiculous. With a Newt, the ota is likely to hit the plate when getting close to the zenith. I get really close with my 8" pier and CEM70 - within the extra 2" radius for sure...

Just my 20 cents worth...

Gordon.

Hello Aldrin,

I do not recognise the shutter mechanism - I have the 3m version - what size is your dome?

If the teeth of the cog is slipping out, then the motor assembly needs to me adjusted to make the teeth engage better. As I said, I do not recognise the mechaanism, so can't help you on what to adjust.

But the motor and rearbox should be on a bracket that can be adjusted. Could you take a picture showing how the assembly connects to the dome?

Gordon.

On 16/01/2021 at 17:34, DeepSkyMan said:

Ok, so having read up on data cabling, and considering that I will laying about 30m of data cable in-line with my power cable, I’m thinking that my best option is outdoor rated CAT6/6A solid F/FTP to minimise the possibility of EM interference.  

A minor wrinkle in the decision making concerns the bending radius of solid CAT6 in the context of the observatory build.  My intention is to run the data cable up through the centre of the observatory and into the pier, which means that it will need to go through a 90 degree change from horizontal to vertical, my concern is that the solid construction might not cope with this and that consequently stranded might be better.  On the flip side, solid cable being less flexible should be easier to run through the conduit.

Can anybody recommend a good cabling supplier?

 

Kind Regards

Paul.

 

 

 

 

Hi Paul,

Just a few thoughts...

Having a single trench is OK, I assume you will have a separate conduit for the power and signal cables?

 I assume the conduit would be a coil? Is so, it should have a draw wire running through it, so all you need to do is securely attach the cable to the wire and pull. It might be neccessary for someone to also push at the other end, if it gets tight... If you are using straight lengths, then push some wire ahead as you join them together.

It would also be a good idea to separate the two conduits as much as you can in the trench. Anything is better than nothing.

If you use armoured cable, ground the armour and it will act like a faraday cage and reduce interference.

And solid strand Ethernet cable can easily be bent pretty tightly. I would not keep tightly bending and straightening it more than neccessary, but making a 90 degree bend should not be much of a problem.

Good luck.

Gordon.

16 hours ago, Paul M said:

Ah! But even though time machines put the traveller somewhere else in space in a lot of films, a real time traveller will already know his geographical location so the calculation just got easier!  

Just a thought...

If they only jump in time, would the earth not be there when you stop jumping?

And possibly for that matter, the rest of the solar system too if you jump enough...

Gordon.

5 hours ago, smr said:

Thanks for the replies. 

Yes my interest is in astrophotography and imaging so I would need an automated dome, I basically want something to house all my equipment in ready to image within a few minutes with everything set up, and sit in the warmth of my house whilst imaging.

At the moment I have my mount in my house and I just take it outside, place on the patio and do the polar alignment, plate solving, and then remote control from laptop in lounge to laptop outside, it probably takes me around half an hour to forty minutes getting everything set up.

I don't want to have a dome where I'd need to go out and move the dome to adjust to the sky so that would have to be automated - what's the cost involved in doing this?

It's also worth mentioning that I am completely useless when it comes to DIY and don't know anyone that would be able to help with diy stuff so it would have to be something which is ready off the shelf so to speak.

As you are finding out, there is no single answer, with both ROR and domes having as many positives as negatives. One common positive is significant reductions in setting up times.

I also note your comment about DIY. Both options will need home assembly but of course you can outsource this for a price. A dome will need an accurate base, probably more so than a ROR. Don't assume it will fit together perfectly out of the box.

Circular or rectangular base will not really matter for the dome, I cast circular pads and it was a lot harder to get both circular, flat and especially level. I have fitted a dehumidifier to each dome and run them 24/7 to prevent the formation of dew.

Where do you expect to go with your telescope? a 2.2m dome is probably limited to nothing bigger than a 12". A 12" Newt will fill the dome leaving little room to get around. I have a 12" f4 newt in a 3m dome and it often gets in the way while working around it... This would be where the ROR scores, but if you intend to always work this remotely, then its not such an impediment.

Hope this helps.

Gordon.

I have the SBIG version and the dessicaant failed. Different design, there is a small bag secured in with the chip. Moisture manaaged to get into the miscolenses and changing the dessicand did not fix it.

After a lot of thought, I disassembled the glass cover over the CCD and put the camera in a warm oven at about 45 degrees C for an hour. Re-assembled with fresh dessicaant and it is like new again.

Not sure of the message, apart from don't ignore it, or if it does get really bad, there is a fix!!

Gordon.

Hi Krikus,

I have a HEQ5 and run a William Optics FLT110 triplet frac on it. Plus filter wheel, cooled camera, OAG and guide camera.

Still within the capabilities of the mount, it guides well.

I would say the 110 frac is a good size for the mount, I guess you could go bigger, but I am happy with the combination. I get nothing like the wind effect a big newt would get...

Hope this helps.

Gordon.

On 19/09/2020 at 23:48, JamesF said:

Yes, I think that's true to a certain point.  We do seem to be moving from "box" style designs to cylindrical form factors.  I suspect that's because cylinders can enclose the same space for less material, making the design both cheaper and lighter.  It's not as though the electronics take up lots of space and restrict the design.  The biggest component in (DSO) cameras seems to be the heatsink.

James

Interesting thread... Thinking about replacing my old SBIG 8300 chipped camera and really not sure about the change to CMOS so this all helps. As I already have the setup for LRGB + NB, I am looking to stay with mono though.

James, I think the use of cylindrical cameras might be for hyperstar configurations

Gordon

1 hour ago, Waldemar said:

I think there is no such thing as 'overkill' when mounts are concerned, especially not when imaging comes into play...
 

 

Your occasional imaging will probably change into serious imaging, once you get into a succes mode with it... 

With an unlimited budget, you can keep on going forever - my point was the 70 would be more than adequate for the VX12, even for long exposure imaging... There is plenty of growing room with the 70 and it is light enough to be portable. The 120 is getting big and heavy.

Removing the price constraint would see us all owning observatory class mounts "just in case". (you with the DDM85 and my ME2 being good examples)

Aperture fever for mounts perhaps..

At the end of the day, it is the budget of the OP that will decide..

Gordon.

Another happy VX12 owner here...

Successfully ran the scope on an NEQ6 for many years, with the belt drive mod fitted after a few years. But mine was in a dome so wind not a problem and also used an OAG to manage drift.

The main drive cogs in the NEQ6 are only 90mm in diameter - the CEM70 is around 150mm so giving a whole lot more suppport than that from the NEQ6. They are also engaged with full contact throughout the axis rotation, unlike the NEQ6. And has a belt drive as standard too.

I am also looking at a replacement for the NEQ6 (actually worn out) and place the CEM70 as the best option for me. For an eternity, I procrastinated over the CEM60 until it went out of production. No concerns about capability, just too much else to do.

For the VX12, I would say the CEM120 was overkill but in terms of cost per kg of payload, is better value. Where you have windbreaks, I am not sure there would be a big advantage with the 120, certainly compared to having a nice guide system...

Good luck with your choice.

Gordon.

+1 for a used HEQ5 or used iOptron CEM25p.

Good luck.

survey completed.. 👍

I noticed the bigger CEM60 has a new stablemate in the CEM70... Built in iPolar and a higher payload. When I saw the 25 was unavailable, I guessed the 60 would not be long for this world. Today I noticed the 60 is marked as unobtainable on the FLO site too.

The price difference between the 60 and 70 was not so bad, assuming you want the iPolar. But the 25 has no obvious replacement. The CEM 40 is twice the price so the only obvious iOptron choice for a £700 mount is the SW HEQ5.

I think they have made a hole in their range...

Gordon.

Hi Vin,

Here is a thought...

Make a list of all the things you do for your better half. Include everything you have compromised on or where she has insisted on something. (I am sure there will be a list) Then explain how it is not a good idea to compromise on the siting and design of the pier and trying to make it do other things. Explain how you are only looking for a small corner and it could be painted any colour she likes, but please don't mess up a design just because... Promise her a new pair of shoes or handbag, or maybe that potted plant she had her eye on...

Good luck.

Gordon.

On 13/06/2020 at 06:33, Rusted said:

I wonder if T-S or Baader do an adapter ring to go between a 3m Ø octagonal building and a 2.7m Ø round tartan dome?

It is all very well making a plywood "adapter ring" but I'd still need a giant bell washer to throw the rain outwards.  Or would I?

The full height [walled] domes are simply placed onto a flat concrete foundation and silicone sealed.

Does anybody here have any direct experience of fitting the short wall Pulsar to a flat roof?

 

Deciding on what domes to get, I also considered the half height dome from Pulsar.

I had drawn up plans to build a wooden structure a couple of metres high out of wood and then use the half height dome on top. (I also considered mounting the full height dome on a lower structure...)

My biggest concern with a wooden structure was the fact wood moves and grows/shrinks with atmospheric conditions and especially for the half height (and the Scopedome for that matter) was the potential for twisting on the base where the dome was secured to a moving structure.

Anyway, the Pulsar website does include some basic drawings and shows there is a flange face on the bottom of the short wall. This would get you half way to making it water tight, with a run of adhesive flashing tape on top might be enough.

HTH.

Gordon.

https://www.pulsarastro.com/ekmps/shops/b585dc/resources/Other/27shortheightdr.pdf

1 hour ago, Rusted said:

Camo? What about a tin of Union Jack?  Suits you sir!

A tin of Tartan paint would look nice also..😂😂😂

On 10/06/2020 at 20:55, Rusted said:

Thanks Dave.

I did some homework and zinc is four times heavier than aluminium and quite costly too.
There is also the problem of having to cut literally every panel [of 60!] to fit.
Which was what I did with the plywood using a sled on the table saw.

Starting a new build from scratch I would make every gore identical.

I heard back from Bresser and they are still looking into delivery costs.
Having raised Gordon's suggestion of a box van they say they would worry about damage in transit.

Pulsar used split pipe insulation for the lorry journey over to Bresser.
With the lorry packed tightly with dome parts.
I was quite mistaken in thinking they used pallets. 
I must have seen that in another video somewhere and filled in the blanks.

Delivery using large pallets forces the use of a much larger vehicle with increased delivery costs.
Then a fork lift is needed at the other end to unload the pallets.
How that works with back garden installations is a further problem.
Not everybody has access to a gang of willing volunteers.

The MD was not amused by seeing the dome in white!  😱
Not sure whether a white Pulsar would look much smaller with its low profile shutter and smoother exterior.
I suppose I could throw a shade net over it to make it look green.
The MD suggested I put the drive electronics in a plastic lunch box and wear a cagoule when it rains. 

If Bresser are packaging the dome to take rough transport, the packing on its own can run into hundreds. I still expect the carriage to hit a grand at least, but don't understand the issue getting a price. I am pretty sure you are not the first to purchase a dome from them, so they really should have a good handle on the costs.

If you collect, it would be a great idea to bring some of the pipe insulation they talk about, plus bubblewrap and some polystyrene foam to pack it for the journey.

But I had another thought.

The plywood covering could be replaced with EPDM roofing sheet. With the rubber glue, it could be pulled tight and glued in place, with some clout nails to hold it. EPDM is used in tyres - particularly the whitewall on tyres, plus it is blended for inner tubes. It is hugely resilient, totally water tight and will not be harmed by nailing it in place. It is not cheap, but is a lot cheaper than starting the whole dome again. It also takes paint too - acrylic water based goes on fine, solvent based paint will adhere better, but will react a bit with the EPDM when wet.  At least worth thinking about...

My local village is about 2 miles away - 3.3km - and from the village, the two Scopedomes in white stands out in the countryside background... The domes are hardly visible from the house, so not a problem for me, but I can understand your MD having a bit of a problem with a white dome, even if white would be better to reflect heat.. Gold is, of course, better so maybe suggest white is a compromise to coating it in gold leaf !! Haha.

Gordon.

16 hours ago, Rusted said:

Thanks Gordon. 

The reference to "low loaders" was my [less than subtle] attempt at humour.
I was going by the description given by Bresser's contact whom mentioned two large pallets.
In fact Pulsar shows the dome sections already palletised on their Facebook page.

I take my homework seriously just like any other self-respecting, obsessive-compulsive shopper for obs. domes.
In fact I came very close to buying a 2.7m a year or so ago until I realised my 7" f/12 just wouldn't fit.
I must have seen every single dome video on YT more than ten times by now.
Read the pulsar website dozens of times in case of change.

Pulsar were talking about a 3.5m model but gave up on the idea. Shame because I was very interested in one.

 

Haha. The low loaders did get me worried for a while. 

I do understand the pallet size. My Scopedomes arrived on huge pallets, I had to cut them into quarters to be able to dispose of them afterwards. I can imagine the trouble they will cause to normal carriers geared up for the usual size of loads.

Until I retired, I was an Engineer in the chemical industry and worked on some large projects worth billions each. I made significant technology decisions in a blink of an eye, compared to the time I spent going over the Pulsar vs Scopedome vs ROR vs any other option. So  I understand what you are going through. Trying to house your 7" frac would also be difficult for the 3m Scopedome. Although it is bigger than the Pulsar, there is a shutter motor which sits at the top of the roof and would take away form of the clearance. But as you do not plan to fit the automation, with some weight on the focuser end, should be OK in the dome. But its more money and you are still caught in the delivery cost problem...

Good luck.

Gordon.

5 hours ago, Rusted said:

The "universe" and Bresser are out to get me!

They admitted the €70 delivery charge was a fiction! 

I can feel a missive to Margrethe Westager in the offing! 

Bresser muttered something about needing police outriders for the two, heavy transport, low loaders.

I don't care how much practice they've had with wind turbine blades.. they'll never get those down our drive!

More later.

Well, I called it.

Hopefully, my comments earlier softened the blow a little for you.

I had two, 3m scopedomes delivered to site in a fair sized panel van. With just the dome section and small wall, they should be easily able to fit them in an ordinary van. Even an open truck as you have nothing to be damaged by some rain.

If you have exhausted your discussion with Bresser, is it worth contacting Pulsar directly and making a trip over to collect yourself? You absolutely will not need a police escort or a heavy low-loader to move one dome.

Good luck getting out of this one.

Gordon.

Such a healthy attitude to life, the universe, everything.

It is a shame you could not catch the water damage earlier, but that is the past and as you say, time to look forward. You are right about the fixed installation making a big difference; little need to plan, look at the clouds, if looking good, then head outside.

A ROR 14 feet off the ground? Love to see that photo.

Good luck with Bresser !!

Gordon.

I do hope the repairs are not too difficult and you make good progress on the rebuild.

Gordon

6 minutes ago, Rusted said:

Thanks Gordon.

You will be the first to know the truth once I hear from Bresser.

As will everybody else here of course.

The price for a fully automated Scopedome is indeed very close to a Pulsar with all "the hidden extras."
The Scopedome just doesn't appeal for my unique situation.

I would have to rebuild the entire structure from the ground up to make it fit.
The Pulsar is a simple, flip-top head job for my particular build.

I get to keep my building with everything I have tailored and improved since I built it.
Security, access, monitor and electronics, Wifi, swivel chair and imaging desk wrapped around the isolated pier.
Nothing changes except I will no longer need a bathing cap. 
 

I agree - The Scopedome needs a dead flat and level base within 1mm. I was going to build it on a wooden platform but decided against it as the engineering grew a lot. Wood moves and if bolted down, might warp the base rings and stop it revolving smoothly. At your elevation, I would think this would be even more difficult so it is probably best not to do it, unless you want to put in some sort of rigid platform to build off.

I am sure you did not plan for this change, especially after you have put in so much work on your original dome, but unless you can waterproof it, damaging the scope, electronics, etc. would be a hobby killer.

Gordon.

Don't think it is false advertising...

They talk about shipping period of a few daays, but point out they cannot accept an order vias the website. I really doubt they keep them in stock, so will be really interested to find out what they say.

For delivery costs I quote the site:

"This article cannot be ordered online! Delivery by forwarding agent requires an individual agreement. Please contact us by phone or e-mail for further information!" I was going to purchase direct from Pulsar and have a carrier bring it over and the manufacturing lead time was a couple of months or more. No idea what covid-19 has done to this so don't be upset if the manufacturing lead is longish...

And I understand what you say about the automation costs. But you can always retrospectively install later, even if you only do the dome rotation motor.

Gordon.

Oh, just followed the link to the Bresser site.

Delivery will only be a few days, but when I enquired of both Pulsar and Scopedome, the manufacturing was a couple of months' lead time. The website also says they need to engage a forwarding agent so forget the Eur70. Are you also adding the automation kit? When added together, this is whaat pushed the Pulsar costs close to the Scopedome for me.

I also saw your earlier post with the pictures. Looks like there is room on the outside, assuming your existing dome is a similar size to the Pulsar.

Good luck,

Gordon.