I've finally ordered a Mesu 200 MK2 (Mesu e200)

[Jonk]

On 01/02/2020 at 13:50, WanderingEye said:

Great, found them, 300mm x 450mm £150, that is not bad considering how much dovetails are... and with M6 tapped holes too.. 👍😀

Here's the reason I thought it would be a good idea...it all fits with room to spare...

Later on, I plan to make a solid block (maybe with adjustment) to hold 3 x Star 71s and a TEC140 or equivalent (in a few years' time!) rather than spaced out on a plate.

For now though, this will be fine to play with.

[WanderingEye]

1 hour ago, Jonk said:

Here's the reason I thought it would be a good idea...it all fits with room to spare...

Later on, I plan to make a solid block (maybe with adjustment) to hold 3 x Star 71s and a TEC140 or equivalent (in a few years' time!) rather than spaced out on a plate.

For now though, this will be fine to play with.

And that will bolt directly to the mount...? Or will you still use a saddle and dovetail...?

[tooth_dr]

It's nice to have so much payload to play with that you can do this!  With my EQ6 and the 180ed alone I am on the threshold of weight.  It will be nice to get a dual rig up and running again.

[Jonk]

21 hours ago, WanderingEye said:

And that will bolt directly to the mount...? Or will you still use a saddle and dovetail...?

The large plate will bolt directly to the mount, with scope rings or whatever clamps I use directly to the plate.

There are dovetails on the photo above as that's what I have for now as a mockup.

I'll use this plate like this for testing whilst I draw up something better, which may take a couple of months to draw / make I guess.

20 hours ago, tooth_dr said:

It's nice to have so much payload to play with that you can do this!

Yes, a very important consideration when deciding a. which mount to buy and b. how much to spend!

I've said it before and I'll say it again, buy once cry once.

[Jonk]

I've had a couple of nights to play and learn how this all works.

1st thing is, very different to what I'm used to - EQMOD and worm drives with backlash etc.

Have spent a long time setting everything up from new, carrying out various PA routines to see what works best (drift aligning for me!), testing all the parts together, I finally got to the stage where I was able to turn on, point, sync, calibrate guider, goto and guide.

Plate solving isn't working correctly, so I need to get to the bottom of that next.

There may be a reason for this - one thing I've learnt about friction drive is slippage.

In RA, I am fairly well balanced. In DEC I am not, as I just connected a couple of scopes for weight to test. These are not balanced at all in all directions, and I found that the RA was driting very noticeably. A quick email with Lucas Mesu and he suggested the RA speed can be adjusted, by letting the mount track in RA for 24 hours, counting the encoder ticks and then he would reset my sitech settings to suit.

I wasn't sure this was it, as this should have been done (and more than likely was) before he despatched it.

I found that slippage was more likely to more out of balance the mount was, so given that it was only DEC that was out, I tested this by pointing in different directions.

Low and behold, the RA tracking speed was fine in places and slow in others. At least I now know.

Back to plate solving, the mount moves to adjust out the error, but then goes back to its starting point immediately - this may be slippage, it may be something else - watch this space.

So, last night, before I packed up, I got what I consider to be very good news, bearing in mind the rough PA, imbalance, wispy cloud and pointing somewhat over the house roof, I was pleased with the 5 minutes I got.

I have never seen my AZ-EQ6 with clean 1" guiding!

Onwards and upwards.

Edited March 7, 2020 by Jonk
Need to learn to type properly

[SamAndrew]

On 09/10/2019 at 20:47, Jonk said:

After all this time, reading, learning and having a word with myself on more than 1 occasion, I've just placed an order for a new Mesu 200 Mk2 mount.

It's being referred to as a Mesu e200 (e for enhanced).

I'm now skint, but hey ho it was a long time coming!

It will be delivered in the next week or so but I can't install it yet as there are a number of things I need to do.

1. Make an adaptor plate to fit my pier.

2. Collect my pier from the powder coaters (very shortly).

3. Purchase some 316 stainless steel billet to make some counterweights. These will easily be less than half the cost of the commercial ones available.

4. Dig a hole and pour the concrete.

5. Locate the mount.

6. Build the observatory around the mount.

7. Hopefully start enjoying it and really getting some good imaging / observing done!

Thanks to @carballada for his enthusiam and updates / videos, it has certainly helped me to push the button.

I'll try and keep this thread updated with progress, but not for a while yet so watch this space if you're interested!

Ciao for now.

Jon

I've just done the same! have wanted one of these for years and finally decided to take the plunge. Think I've got the last one of the current batch as the price of the next batch is expected to go up due to the weakened Pound.

Just bought a wedge for now as I'll fit it to a pier - will visit the idea of the bent pillar in the future. Weights and wedge are on order - so may be a while before I can collect the mount.

Plan to mount a dual rig to it, so I will be interested to see how you get on.

Top of my todo list is designing a new observatory to house it

[Jonk]

Nice! Hopefully a decision you won’t regret, I don’t think you will 👍🏻

[ZS1RA]

On 09/10/2019 at 21:47, Jonk said:

After all this time, reading, learning and having a word with myself on more than 1 occasion, I've just placed an order for a new Mesu 200 Mk2 mount.

It's being referred to as a Mesu e200 (e for enhanced).

I'm now skint, but hey ho it was a long time coming!

It will be delivered in the next week or so but I can't install it yet as there are a number of things I need to do.

1. Make an adaptor plate to fit my pier.

2. Collect my pier from the powder coaters (very shortly).

3. Purchase some 316 stainless steel billet to make some counterweights. These will easily be less than half the cost of the commercial ones available.

4. Dig a hole and pour the concrete.

5. Locate the mount.

6. Build the observatory around the mount.

7. Hopefully start enjoying it and really getting some good imaging / observing done!

Thanks to @carballada for his enthusiam and updates / videos, it has certainly helped me to push the button.

I'll try and keep this thread updated with progress, but not for a while yet so watch this space if you're interested!

Ciao for now.

Jon

I’m about to order but was told that there’s a 10 week lead time. I don’t know how I’m going to contain myself once I hit the BUY button

[ZS1RA]

On 30/01/2020 at 12:23, Jonk said:

I received this photo today...

16.5kg each. This weekend I’ll put one on and get the mount slewing and under control hopefully.

What are the dimensions to give you 16kg

[Jonk]

14 hours ago, ZS1RA said:

I’m about to order but was told that there’s a 10 week lead time. I don’t know how I’m going to contain myself once I hit the BUY button

The last conversation I had with the UK reseller was the motors availability was holding back the next batch, and they were due in August. Not that I'm going to buy a 2nd mount!

14 hours ago, ZS1RA said:

What are the dimensions to give you 16kg

I used 150mm diameter stainless steel 316 billet (marine grade) at 125mm length, with a bronze insert pressed in and polyacetal tipped thumbscrew.

[Davey-T]

1 hour ago, Jonk said:

polyacetal tipped thumbscrew.

Hi Jon, do you have a source for these or did you have to make them ?

Dave

[Jonk]

Alright Dave? I bought them from Berger Tools -> https://www.berger-tools.co.uk/Hand_Knobs_Star_Knobs_Wing__Knurled_Thumb_Screws__Nuts/

Take your pick!

[SamAndrew]

Have done some initial tests with mine. Hope to have it up and running fully in the next couple of months ready for the autumn. I think this guide graph is certainly hitting the limit of resolution you can get through a 50mm guider. Next test will be guiding at a longer focal length. I did have to adjust the RA ticks per revolution as it was drifting in one direction slowly.

[ZS1RA]

On 09/07/2020 at 12:49, Jonk said:

The last conversation I had with the UK reseller was the motors availability was holding back the next batch, and they were due in August. Not that I'm going to buy a 2nd mount!

I used 150mm diameter stainless steel 316 billet (marine grade) at 125mm length, with a bronze insert pressed in and polyacetal tipped thumbscrew.

Thanks, very useful information. I also just noticed that there is a big difference on the pier attachment. I am puzzled by the Azimuth adjustment. Do you know how fine adjustments to the Azimuth is done,?

[tooth_dr]

14 hours ago, SamAndrew said:

Have done some initial tests with mine. Hope to have it up and running fully in the next couple of months ready for the autumn. I think this guide graph is certainly hitting the limit of resolution you can get through a 50mm guider. Next test will be guiding at a longer focal length. I did have to adjust the RA ticks per revolution as it was drifting in one direction slowly.

The only time I got figures like with my Mesu e200 was a fortnight ago when I changed from OAG to finderscope guider, and when setting up a new profile in PHD2 I incorrectly entered the FL of the guidescope as 500mm (that is the focal of my imaging scope) as opposed to 185mm.  That is very impressive - have you definitely entered the right focal length in PHD2 so that it is reporting the right figures?!

What do you think would be gained from guiding at a longer FL?  If you can achieve an RMS of 0.21", then you can image at a resolution of 0.420"/px.  With your 1600MM you could image at a focal length of 1850mm and still achieve 0.42"/px just by using the finderscope.

Good to see such excellent results early on though 👍

 

[SamAndrew]

Yep I doubled checked, I was guiding at 4.07"pp so 0.05pixels = 0.2". The question is how accurately can phd meause the star centroid at 4.07"pp. With better guide resolution, the level of precision will be better.