Observing pier hight

[crush]

Hi all.

I am thinking of building a viewing platform and having a permanent pier for observing but from what I have been able to find, I am not sure what hight the pier should be.

Is there a rough setting for the hight of a pier?

Does it make a difference what scope is used?

Is it just personal preference? 

Are piers mainly used for AP not observing? If used for both is there a difference between them? 

Sorry if the questions seem a bit daft but I am still very new to this hobby.

Thanks for reading.

[Carbon Brush]

Not at all a daft question. In fact it is a question I asked myself when building my observatory.

Yes scope type does matter. Certainly for visual use.
Think of a long refractor looking near the zenith, the eyepiece is near the floor.
Now a short tube MAK/SCT. The eyepiece does not move by much.
Now put a big newtonian reflector on there and fetch a step ladder to reach the eyepiece!
Is your current scope a keeper? Might you be tempted to try other scopes? Yes of course you will.

A pier purely for AP can be any height - provided it clears fences, etc.
The inconvenience of kneeling, or climbing a ladder to fiddle around is not that often.

When building my pier, I wanted to ensure the pier was low enough for a 10" reflector to sit on top of a mount (bigger than EQ5 that I would probably buy) and the roof slide over.
I built a bit low, meaning I could add a spacer to increase height if necessary. Studs protruding from the pier top to a plate gave height adjustment.
My Alter D6 mount with Intes MN78 on top, parked horizontally,  does clear the roof.
A 25/30cm step stool is a good idea for viewing near the zenith.

Have a try out with a tripod based mount and any scopes you can borrow. That will give you a good idea of a target height.

Good luck with the research, David.

 

[crush]

Hi @Carbon Brush thanks for the reply.

It seems like a lot in this new hobby I have found, its not straight forward. This is really good info though.

At this moment I have a SkyWatcher 254x1200 dob mounted on a AZ EQ6 mount and tripod, when I read that it could put the eyepiece in odd positions I thought people were exaggerating but now I know they were not. I have a stepladder when viewing but there are some positions were I just have to admit defeat.

So if I build the pier a bit shorter to cater for the dob it would be a good idea to have an extension for a refractor that I am sure to have at a later date while keeping in mind I may want to build a shed over it at a later date as well.

Don't know anyone near me yet with a telescope but I do need to get round to joining my local club.

 

[mikeDnight]

 I've always found tripods and piers to be too short. For me there's nothing worse than being scrunched up while observing, as it hinders breathing and becomes uncomfortable and distracting.  Years ago after buying a sizeable refractor I decided that the scope, heavy mount and my back would benefit from a tall pier. I also had the silly viewpoint at the time that looking directly through the scope was better. With all this in mind my pier, which was buried into my back lawn, had to be above head height including the mount head. It worked well for many years, and when not in use I'd take the scope inside the house and cover the mount and electronics with a canvas garden chair cover tied with a bungee cord. It never got wet! 

To give an idea of the pier height I was 6 ft 1" tall.

 

Today I still use a pier for most of my observing. When I designed this latest pier I wanted the scope to be comfortable to observe with from a standing position, although nowadays I always use a diagonal prism. So I can stand and look down into the eyepiece without being uncomfortable.  My pier is a 6" steel square section tube made by a local sheet metal worker, and has a 7" square, 1/2" thick top plate. These days I observe from the comfort of an observatory, and after burying a couple of feet of the pier int a hole filled with concrete, and the added height of the observatory floor 1 ft above ground, the pier top allows me to observe from both a standing position, and with the use of a hydraulic swivel chair and by tilting the diagonal, also from a comfortable seated position.  Again my scopes are refractors, so the pier needs to be tall. If for a Newtonian I'd design it so that the scope eyepiece would be in a comfortable position view able from a standing position.

In this second pic, the top of the mount head is just shy of 6ft above floor level.

It is very comfortable to stand and look down into the eyepiece while observing the Moon and planets. 

Equally I can observe while seated by simply tilting the diagonal.

 

 

[M40]

This is an interesting conundrum. How about something like a Todmorden pier where you can add or remove blocks to suit your telescope? You could start with a height to suit your reflector and add blocks at a later date if you change to a refractor. 

[bosun21]

1 hour ago, crush said:

At this moment I have a SkyWatcher 254x1200 dob mounted on a AZ EQ6 mount and tripod, when I read that it could put the eyepiece in odd positions

If you are doing visual you can always flip your AZ-EQ6 into Alt/Az mode. This will keep the eyepiece in a respectable position for observing with your Newtonian.

[crush]

@mikeDnight that is a very nice set up you have. At only 5' 9" I would of needed a stepladder to reach the eyepiece in your first set up. The info from your pier set up now is really interesting and answers another one of my questions that it is personal preference as well as including how tall you are.

The photo from outside with your scope just peaking out of the top has raised another question for me. 

I was planning on making a raised decking platform of about 1m high, the reason being I have a railway fence at the rear of my house and at that hight the top of the fence would be just above the horizon giving me as much sky as possible. Am I expecting to much from a scope to be looking low in the sky even in good seeing conditions?  

[crush]

@M40 I had looked at the Todmorden pier and have not yet ruled it out for the reason of being able to adjust the hight, but if I do go with a raised platform I am not sure it would be the way to go. 

[crush]

@bosun21 I have used the mount in AZ but I am trying to use Ascom and CdC with varying degrees of success and as I found in an earlier topic post I made the rooky mistake and was struggling to get it lined up, so it is at least for now in EQ mode.

[bosun21]

9 hours ago, crush said:

@bosun21 I have used the mount in AZ but I am trying to use Ascom and CdC with varying degrees of success and as I found in an earlier topic post I made the rooky mistake and was struggling to get it lined up, so it is at least for now in EQ mode.

You can use ASCOM in AZ mode as well as plate solving. I use Sharpcap for plate solving in both EQ and Alt/Az mode.

[crush]

Thanks for the info I will keep it in mind.

[crush]

I have been looking into how to do a base for this and came across info that it does not need to be to wide but does need to be deep the dimensions were 15 inch wide by 5 foot deep, the depth seems a bit excessive to me.

Does this seem correct?

[Carbon Brush]

For a definitive answer you need a consulting engineer who specialises in groundworks and foundation😁.

In reality the size depends on the size/weight of the pier.
If you make it 60cm deep, that is plenty for most purposes.
As for diameter, that is a bit different.
If you want a 'perfect no instability' pier, you don't want to be stamping your feet on it. Hence the idea of a narrow column.

However, you are going to be standing on the ground near the pier.
If you put down a bit of decking, floating over the pier, you isolate the pier from vibrations.
My observatory has a one piece foundation and concrete pillar.
Later the shed base was poured - leaving a gap to the pillar.

When building my setup, there was much less information readily available.
The lump below ground was almost 1 metre cube. With hindsight, more than required.
I figured that once you start to dig, it is little effort to dig more. Concrete is not that expensive.
A base that is too big juust gives you more excersize digging and costs a bit more sand & cement. Having already hired/borrowed the mixer.
If the base is not good enough, you have to dig it out and start again.

If the ground moves seasonally, or more slowly, it is not a big issue. Just visit your polar alignment occasionally.
If ground moves slowly, your base was not deep enough.

I'm sure others will be along with their experiences.

[Naughty Neal]

Height might depend on comfort, some like to stand ideal for straight thru viewing .   

Others will like to be seated esp if using mirrors/prisms and  at the eyepiece for some time, there is no one answer.

Edited April 18 by Naughty Neal

[crush]

@Carbon Brush that is really useful information and has helped me understand a bit more how I could make what I want to do work. I do not have any experience in building so thanks.

 

@Naughty Neal I have started to understand there is no exact answer that I was hoping to get but the answers I have had have definitely given me a lot to think about.

 

It is going to be interesting and hard work to build and hopefully it will work out.