Counterweights for HEQ5 and Esprit 100ED

[teoria_del_big_bang]

This sounds a silly question as the answer should be obvious (when you find them they often are).

But I now have a SW Esprit 100ED which is surprisingly heavy. In addition I have the flattener, filter wheel, and ASI1600 MM camera fitted and currently a fairly lightweight 50mm guidescope and Altair camera. I have not weighed all this lot and perhaps I should.

But I had looked about on Google images at pictures of similar setups and the few I found seem to show the HEQ5 with both counterweights attached but not at the very end of the bar. But with my bar fully extended and both weights as far down as I can get it still needs about another 1/2 kilo to balance.

It maybe the images I looked at had the extension bar added and I cannot tell.

So there must be plenty on this forum with similar setups do you have to use an extension bar or extra weights?

If so is it better to get a third 5 Kg weight which means the weights can go nearer to the mount than right at the end of the bar or stick to 2 weights with an extension?

Steve

[vlaiv]

That is kind of interesting, since your setup should not be that heavy. I've found that I need third counter weight with 12kg+ setup - which I would not recommend anyway on Heq5. I did use it like that, but it was at its limits (8" F/6 tube from dob + rings + camera + 60mm guide scope and guide camera).

Esprit 100 is listed to weigh at 6.3Kg. ASI1600 is fairly light weight camera. Not sure how heavy is your filter wheel. Guide scope should also be light.

I balance ~9kg scope (RC 8" + 50mm M90 extension and upgraded focuser), ASI1600, filter drawer and OAG and additional 1Kg weight to setup in DEC with 2 5kg counter weights without a problem. Counter weights don't even go down to the end of the shaft.

Maybe you can optimize your setup a bit? In the same way that you can get disbalance by moving CWs up and down the bar - you can do the same on scope side. If your guide scope is mounted on top of your imaging scope, can you change the distance between the two - can you get your guide scope closer to the imaging scope? Where is your filter wheel "pointing"? If body of filter wheel is rotated so that it is "up" or away from mount - bring it down so that it "hangs" rather than being "up" (silly usage of directions, I know, but hopefully you will get what I mean).

Btw, it is better to add more weight closer to mount then use extension bar as far as guiding is concerned. Setup will be heavier and there fore more solid, it will indeed produce more friction on bearings, but arm momentum will be smaller and mount more responsive to guide commands.

 

[Adam J]

1 hour ago, teoria_del_big_bang said:

This sounds a silly question as the answer should be obvious (when you find them they often are).

But I now have a SW Esprit 100ED which is surprisingly heavy. In addition I have the flattener, filter wheel, and ASI1600 MM camera fitted and currently a fairly lightweight 50mm guidescope and Altair camera. I have not weighed all this lot and perhaps I should.

But I had looked about on Google images at pictures of similar setups and the few I found seem to show the HEQ5 with both counterweights attached but not at the very end of the bar. But with my bar fully extended and both weights as far down as I can get it still needs about another 1/2 kilo to balance.

It maybe the images I looked at had the extension bar added and I cannot tell.

So there must be plenty on this forum with similar setups do you have to use an extension bar or extra weights?

If so is it better to get a third 5 Kg weight which means the weights can go nearer to the mount than right at the end of the bar or stick to 2 weights with an extension?

Steve

You need to provide a image and also weigh it for people to comment, 

I would also be very interested in the result as this is the setup that I intend to use. 

Perhaps the 6.3kg is without the tube rings and dove tail. Only one way to find out mate. 

Got to be honest though my setup which is identical to yours but with a 130PDS balances with just 1 x 5kg counter weight 1cm from the end of the bar. I refuse to believe that the Esprit 100 is more than 5kg heavier than my 130PDS....of course the second weight cant move all the way to the end of the bar though as the first is in the way., but the 130PDS is 4kg with its tube rings attached.

Best to weigh the scope with its rings and dovetail and then weigh it with the rest of your stuff added. That way there is no doubt. 

https://starizona.com/store/manufacturers/sky-watcher/esprit-100mm-ed-triplet-apo-refractor

16.3 LB according to Starazona's web page that is 7.4Kg not 6.3Kg.....huum the plot thickens. That extra Kg could well push it over two counter weights. But the total should still be under 10Kg for your equipment and I would hope the scope is closer to the pivot point than the weights. 

Adam 

Edited October 7, 2019 by Adam J

[teoria_del_big_bang]

53 minutes ago, vlaiv said:

That is kind of interesting, since your setup should not be that heavy. I've found that I need third counter weight with 12kg+ setup - which I would not recommend anyway on Heq5. I did use it like that, but it was at its limits (8" F/6 tube from dob + rings + camera + 60mm guide scope and guide camera).

Esprit 100 is listed to weigh at 6.3Kg. ASI1600 is fairly light weight camera. Not sure how heavy is your filter wheel. Guide scope should also be light.

I balance ~9kg scope (RC 8" + 50mm M90 extension and upgraded focuser), ASI1600, filter drawer and OAG and additional 1Kg weight to setup in DEC with 2 5kg counter weights without a problem. Counter weights don't even go down to the end of the shaft.

Maybe you can optimize your setup a bit? In the same way that you can get disbalance by moving CWs up and down the bar - you can do the same on scope side. If your guide scope is mounted on top of your imaging scope, can you change the distance between the two - can you get your guide scope closer to the imaging scope? Where is your filter wheel "pointing"? If body of filter wheel is rotated so that it is "up" or away from mount - bring it down so that it "hangs" rather than being "up" (silly usage of directions, I know, but hopefully you will get what I mean).

Btw, it is better to add more weight closer to mount then use extension bar as far as guiding is concerned. Setup will be heavier and there fore more solid, it will indeed produce more friction on bearings, but arm momentum will be smaller and mount more responsive to guide commands.

 

Cheers @vlaiv Yes one reason for posting what seems a very basic question is that I was surprised I might need a third weight.

But good tip about filter wheel. It is a 7 position SX USB which is well built and weights a bit and yes I do have it pointing up so will change that.

I am really surprised because my previous setup was the same with the exception of the main scope which was a WO Z73 - very light compared to the Esprit but I only has one weight and it was not at end of the unextended bar. So thought I would need two weights but no any more.

The guidescope and camera are very light and are on top of main scope but only the width of a vixen dovetail and normal scope rings.

Yes I have a slightly longer Losmandy for my Esprit than the very short supplies one so I can balance it easier without having the bar partially out of the saddle but it is aluminium and obviously very close to mount so should not be a big issue. Vixen for mounting guidescope is also aluminium.

Let me rotate the filter wheel and see if that gets me in balance, failing that I am just wondering if something is stopping the bar extending fully anyway and it is actually shorter than it is designed to be - I will check when I get home from work.

Thanks for the advice 🙂

Steve

 

[teoria_del_big_bang]

17 minutes ago, Adam J said:

You need to provide a image and also weigh it for people to comment, 

I would also be very interested in the result as this is the setup that I intend to use. 

Perhaps the 6.3kg is without the tube rings and dove tail. Only one way to find out mate. 

Adam 

Cheers Adam,

I will weigh the rig and take a pic. I am in the middle of fitting a better scope to use for guiding as my current starwave 50 mm is okay but some big halos on the stars, but the new one is heavier so will add to the issue.

I also need to look and double check the bar is extending fully, just something I thought of just now. I can't see why it should not be but should check to be sure.

Steve

[Adam J]

10 minutes ago, teoria_del_big_bang said:

Cheers @vlaiv Yes one reason for posting what seems a very basic question is that I was surprised I might need a third weight.

But good tip about filter wheel. It is a 7 position SX USB which is well built and weights a bit and yes I do have it pointing up so will change that.

I am really surprised because my previous setup was the same with the exception of the main scope which was a WO Z73 - very light compared to the Esprit but I only has one weight and it was not at end of the unextended bar. So thought I would need two weights but no any more.

The guidescope and camera are very light and are on top of main scope but only the width of a vixen dovetail and normal scope rings.

Yes I have a slightly longer Losmandy for my Esprit than the very short supplies one so I can balance it easier without having the bar partially out of the saddle but it is aluminium and obviously very close to mount so should not be a big issue. Vixen for mounting guidescope is also aluminium.

Let me rotate the filter wheel and see if that gets me in balance, failing that I am just wondering if something is stopping the bar extending fully anyway and it is actually shorter than it is designed to be - I will check when I get home from work.

Thanks for the advice 🙂

Steve

 

The fact that you also have a losomandy on a HEQ5 implies to me that you have replaced the basic clamp??? That must add weight on the scope side. 

Also if you have a vixen dove tail on top and the added weight on the longer losmandy they I that really will have an effect. 

Like I say, you need to weigh it all. 

Adam 

Edited October 7, 2019 by Adam J

[teoria_del_big_bang]

I have fitted a fairly hefty Geoptic saddle and puck so yes that will add some weight to the scope side but it is aluminium and the old clamp and puck were removes so should not be too much extra.

Steve

[Adam J]

5 minutes ago, teoria_del_big_bang said:

I have fitted a fairly hefty Geoptic saddle and puck so yes that will add some weight to the scope side but it is aluminium and the old clamp and puck were removes so should not be too much extra.

Steve

Yes but its that saddle + the longer losmandy + the vixen on top and the guide scope. All in all that will be at least another Kg if not more.even if they are aluminium That 1kg could be all it takes to move it over two weights. 

Ill be fixing my guide scope just to the top of the rear ring and changing the losmandy out for a solid vixen bar very little additional weight that way. 

At any rate, as above you really dont want it to be over two weights with a HEQ5 pro.  If you need more weight then I would not be going for another 5kg weight at any rate.  

Adam 

Edited October 7, 2019 by Adam J

[vlaiv]

Not sure if that helps, but I forgot to mention - I have same modification on my HEQ5 - Geoptic dual saddle plate (vixen + losmandy) and their puck as well.

Like I've written - it balances with 9kg scope + accessories ...

[teoria_del_big_bang]

1 minute ago, Adam J said:

Yes but its that saddle + the longer losmandy + the vixen on top and the guide scope. All in all that will be at least another Kg if not more.even if they are aluminium That 1kg could be all it takes to move it over two weights. 

Ill be fixing my guide scope just to the top of the rear ring and changing the losmandy out for a solid vixen bar very little additional weight that way. 

At any rate, as above you really dont want it to be over two weights with a HEQ5 pro.  If you need more weight then I would not be going for another 5kg weight at any rate.  

Adam 

Yes on reflection I agree about not adding another weight.

I will actually be interested to see what the scope rings weight they are fairly hefty things .

I will report back with the weights.

If my new guidescope I intend to use is heavier I wonder if a side by side setup would be better, I guess it is a try and see as the guidescope moves closer to the mount but then the added weight of the dual saddle? 

I did have my  Z73 setup like this in early stages but it had the skywatcher guidescope mount which is a great piece of kit but it weights a lot and really I didn't need it, as I always found a guide star without needing adjustment, so when I took it off decided just to reduce weight as much as I could so took the side by side ADM bar off as well and mounted guidescope on top of Z73. 

Steve

 

[vlaiv]

Just for reference, I measured length of CW bar on my mount and it is ~ 20.2-20.3 cm long fully extended. Gives you comparison value to see if yours is fully extended as well or maybe shorter or something.

[Tomatobro]

Its been a while since I sold my HEQ5 pro but I made up a 6 inch C/W shaft extension out of brass so I could move the weights out to get the balance. It had a belt modification fitted and it tracked very well with PHD, 60mm Altair guide scope and a ZWO ASI220 mono camera. I think you can buy a proper Skywatcher version (extension shaft)

I also had a new saddle fitted and it did move the scope out and away from the mount head a little more which further aggravated the balance issue

Flo list a bar under Skywatcher accessories and in the write up give its measurements. 

Edited October 7, 2019 by Tomatobro
extra comment

[teoria_del_big_bang]

Right, it all starts to make sense now. It's just maths. Although I have not done the maths as such as I have not measured any distances from centre of rotation. It does surprises me what some of this gear does weigh. The bar is fully extended by the way and measures same as @vlaiv

Now I did make one big error when balancing in that I left the lens cap on the scope and that weighs over 200 g.  With this removed as it stands I can just balance the rig with the two 5Kg weights (that do weight 5Kg I checked) but they are at the very end of the bar.

What is on top of mount:-

• New Geoptic saddle and puck (replaces old saddle & puck so not too much difference) ------------    1.02 Kg
• Losmandy Dovetail --------------------------------------------------------------------------------------     0.67 Kg
• Primaluce clamp (Used on Losmandy at top for safety  to stop rig sliding down when fitting to mount 0.29 Kg
• Supplied Scope Clamps (420g each x2) ----------------------------------------------------------------      0.84 Kg
• Esprit 100ED + Flattener + 20 mm spacer --------------------------------------------------------------     6.30 Kg
• Filter wheel + filters --------------------------------------------------------------------------------------     0.78 Kg
• ASI 1600 MM Camera -----------------------------------------------------------------------------------     0.43 Kg
• Vixen Dovetail on top of Main Scope rings to mount guidescope to ---------------------------------      0.47 Kg
• Guidescope, guidescope mount & Altair Guidescope -------------------------------------------------      0.85 Kg
• TOTAL ----------------------------------------------------------------------------------------------------     11.65 Kg

I didn't weight the dew bands and controller for these but they are not much.

There looks a lot on there but there was reasoning behind it.

The extra clamp under the losmandy is really useful as when lifting the scope you can safely slide it into the dovetail in the clamp and it only slides down as far as the clamp. So you are not trying to hold around 10Kg of expensive gear in one hand while tightening the clamp with the other on a cold night risking the whole lot sliding down onto the deck. Maybe overkill but I really feel much safer this way. Also it marks exactly the right position for balance each time it is mounted. I guess I could save 200 g if I replace with a 3D printed stop somehow.

The vixen on top of the main scope was for reason of rigidity to stop any flex between main scope and guidescope but again maybe this could be shorter and save another 200 to 300 g if it is shorter, or maybe if no issue with flexing then I could remove it and save all the 470 g and at same time it would lower the height of the guidescope.

So looks like I can easily save around 600 g and lower height of rig together with turning the filter wheel 180 degrees might in effect save 1 Kg and I then should be easily balanced with the two weights. I will let you know when I get this done. Only issue then is the new guidescope will weigh a bit more than the 50mm one I currently use and maybe have to decide do I continue to live with the current guidescope to save weight.

Steve

Edited October 8, 2019 by teoria_del_big_bang

[Adam J]

On 07/10/2019 at 21:17, teoria_del_big_bang said:

Right, it all starts to make sense now. It's just maths. Although I have not done the maths as such as I have not measured any distances from centre of rotation. It does surprises me what some of this gear does weigh. The bar is fully extended by the way and measures same as @vlaiv

Now I did make one big error when balancing in that I left the lens cap on the scope and that weighs over 200 g.  With this removed as it stands I can just balance the rig with the two 5Kg weights (that do weight 5Kg I checked) but they are at the very end of the bar.

What is on top of mount:-

• New Geoptic saddle and puck (replaces old saddle & puck so not too much difference) ------------    1.02 Kg
• Losmandy Dovetail --------------------------------------------------------------------------------------     0.67 Kg
• Primaluce clamp (Used on Losmandy at top for safety  to stop rig sliding down when fitting to mount 0.29 Kg
• Supplied Scope Clamps (420g each x2) ----------------------------------------------------------------      0.84 Kg
• Esprit 100ED + Flattener + 20 mm spacer --------------------------------------------------------------     6.30 Kg
• Filter wheel + filters --------------------------------------------------------------------------------------     0.78 Kg
• ASI 1600 MM Camera -----------------------------------------------------------------------------------     0.43 Kg
• Vixen Dovetail on top of Main Scope rings to mount guidescope to ---------------------------------      0.47 Kg
• Guidescope, guidescope mount & Altair Guidescope -------------------------------------------------      0.85 Kg
• TOTAL ----------------------------------------------------------------------------------------------------     11.65 Kg

I didn't weight the dew bands and controller for these but they are not much.

There looks a lot on there but there was reasoning behind it.

The extra clamp under the losmandy is really useful as when lifting the scope you can safely slide it into the dovetail in the clamp and it only slides down as far as the clamp. So you are not trying to hold around 10Kg of expensive gear in one hand while tightening the clamp with the other on a cold night risking the whole lot sliding down onto the deck. Maybe overkill but I really feel much safer this way. Also it marks exactly the right position for balance each time it is mounted. I guess I could save 200 g if I replace with a 3D printed stop somehow.

The vixen on top of the main scope was for reason of rigidity to stop any flex between main scope and guidescope but again maybe this could be shorter and save another 200 to 300 g if it is shorter, or maybe if no issue with flexing then I could remove it and save all the 470 g and at same time it would lower the height of the guidescope.

So looks like I can easily save around 600 g and lower height of rig together with turning the filter wheel 180 degrees might in effect save 1 Kg and I then should be easily balanced with the two weights. I will let you know when I get this done. Only issue then is the new guidescope will weigh a bit more than the 50mm one I currently use and maybe have to decide do I continue to live with the current guidescope to save weight.

Steve

Did you sort this? How is it guiding now? 

[teoria_del_big_bang]

On 06/02/2020 at 10:54, Adam J said:

Did you sort this? How is it guiding now? 

Hi,

Well sort of, I did get the weight down and used it once or twice with reasonable guiding (can't remember exactly what I achieved though) but then I bought a new CEM60 mount with more payload capacity. Due to weather I have only had one session with this new mount so not really sure how good I can get this to guide but should know soon if the cloud clears.

It may well be when I get a few more sessions under my belt with the new mount I will be asking for help again, but will try to get it the best I can first.

 

Steve

Edited February 7, 2020 by teoria_del_big_bang