EQ8 or Mesu200 advice please

[RayD]

I am looking to get a brand new mount for my new observatory which I am currently building.  I have the AZ EQ6 out in Spain which I am very happy with, and am looking at possibly getting the EQ8 for here for a small amount of future proofing.  However, I could go to a Mesu200 so my question is, with me only really doing small(ish) refractor imaging (100mm Esprit), would I or could I benefit from going for the Mesu, or would you think the EQ8 would "more" than meet my demands i.e is the Mesu200 really that much better than the EQ8?

I do use filter wheel, guide scope etc. but obviously don't really load things up massively, and the largest OTA I use is the C8 with either a small CCD or DSLR, so I assume the weight capacity of the EQ8 would be fine.

I'm ok to spend the additional money, but would prefer to only if opting for the Mesu would be noticeably worthwhile.

What are your thoughts?

[Dixie]

Ray

Do you plan on possibly getting a heavier scope at some point in the future?

R

[RayD]

Just now, Dixie said:

Ray

Do you plan on possibly getting a heavier scope at some point in the future?

R

I currently don't plan it, but you know how it is with this hobby, you see something you can't resist.........

I think I would probably only go up to something like the SW Quattro if I did get anything bigger along the reflector lines.

[ollypenrice]

Well my thoughts are going to be very predictable to anyone who reads this forum.  The quality of construction of the Mesu is a lot further ahead of the EQ8 than the price difference between the two might suggest. I watched a strip down video of the EQ8 on here and thought that some aspects of the construction were downright grim. Grubscrews tightening down onto threads. Ouch! You will not find that on a Mesu. My own experience of the EQ8 was that it had backlash in dec for part of the wheel rotation. I was accused of scouring the net in search of similar problems so I would simply advise you to check that out and see how much scouring you need to do. 

I'm not anti-Skywatcher. I would honestly ask you whether, at the weight and focal length of an Esprit 100, you need more than an EQ6. Under guiding it is a very good mount and fantastic value. I use two of them here. I find that our Avalon Linear is more consistent than the EQ sixes and, on average, a little more accurate - but is also more affected by wind. It was also a lot more expensive but will, I think, run for longer without attention. We also have a Takahashi EM200. It is beautifully made but, despite its astonishing price, does not significantly out perform the EQ sixes under guiding. (That is about as fair a comparison as I can make. I wonder how many flying bricks it will attract.)

You mention future proofing. If this future proofing involved doubling up your Esprit 100 with a second one then the EQ8 might well make sense. If it meant doubling your focal length and so your need for guiding precision then, in my view, you would do much better with the Mesu. I don't think weight has much to do with it.  In my view the EQ8 and the Mesu are big mounts. The Mesu, however, is an big and an accurate mount.

Olly

[RayD]

Thanks Olly, a very comprehensive response.

I think the future proofing I refer to is probably more an increase in focal length than pure weight.  I do also want to ensure accurate tracking/guiding, so in this regard your comments seem to intimate the Mesu making more sense.

Appreciate your input and will look along this route I think.  I'd rather go OTT (relatively speaking) now, than in 2 years look back with regret.

Are there any specific mount adaptor requirements for the Mesu200 i.e. does it need an adaptor specially supplied by Mesu Optics?  I am getting a custom pier made so can get this incorporated in to the design.

Also am I right in thinking the Mesu is 24V?

[ollypenrice]

Our Mesu is 12 volt but it's an original spec one. I think the one on our robotic shed is 12 volt as well. In fact I'm sure it is, and that's a much newer spec. Not sure about the pier top. There will be a drawing on the website though.

Olly

[derrickf]

Ray,

I have owned an EQ-8 and currently have a Mesu200; I usually image at medium to long focal length (1700 - 2500mm) - as you know it is image scale that is important but focal length serves as a reasonable analogue in this case.

The EQ-8 was a very sturdy mount with low PE and was easy to use via EQ-ASCOM. Mechanically the mount was adequate but even after less than a year there was some cosmetic tarnishing of fasteners etc. that indicated where low cost materials had been used. Imaging performance at 1500 - 1700mm was IMO just about acceptable - I didn't need to be constantly fiddling with mount balance etc and would typically lose about 15-20% of subs due to mount aberrations (small transient jumps, slips, unexpected drift etc.) - at a shorter focal length (more generous image scale) these may not have been noticeable but imaging at < 1 arcsecond pp is pretty unforgiving.

I found imaging at longer focal length (>2000mm) was frustrating and I found myself losing significant amounts of imaging time trying to fine tune the mount to overcome the effects of the mechanical compromises made in the mount design and manufacture. Typically I was lucky not to lose more than 50% of images from a session. Remember though that this is fairly extreme imaging at around 0.5 arcseconds pp which not many people engage in. The net result was that I spent far too much precious imaging time nursing the mount and far too little of the available clear sky time actually collecting usable photons.

I replaced the EQ-8 with a Mesu200 about 2 years ago and after the initial setup have lost very few images to mount issues. On the odd clear night I open up the observatory, fire up all the equipment and image without any concerns at all about whether the Mesu200 carrying my qpprox. 50kg imaging setup will perform as expected - it just does. Typically I see guide errors at around 0.25 arcseconds rms with no unexpected glitches, farts or transients.

I can think of no better endorsement of a mount for imaging - the Mesu just works as it should.

HTH

 

Derrick

[RayD]

1 hour ago, derrickf said:

Ray,

I have owned an EQ-8 and currently have a Mesu200; I usually image at medium to long focal length (1700 - 2500mm) - as you know it is image scale that is important but focal length serves as a reasonable analogue in this case.

The EQ-8 was a very sturdy mount with low PE and was easy to use via EQ-ASCOM. Mechanically the mount was adequate but even after less than a year there was some cosmetic tarnishing of fasteners etc. that indicated where low cost materials had been used. Imaging performance at 1500 - 1700mm was IMO just about acceptable - I didn't need to be constantly fiddling with mount balance etc and would typically lose about 15-20% of subs due to mount aberrations (small transient jumps, slips, unexpected drift etc.) - at a shorter focal length (more generous image scale) these may not have been noticeable but imaging at < 1 arcsecond pp is pretty unforgiving.

I found imaging at longer focal length (>2000mm) was frustrating and I found myself losing significant amounts of imaging time trying to fine tune the mount to overcome the effects of the mechanical compromises made in the mount design and manufacture. Typically I was lucky not to lose more than 50% of images from a session. Remember though that this is fairly extreme imaging at around 0.5 arcseconds pp which not many people engage in. The net result was that I spent far too much precious imaging time nursing the mount and far too little of the available clear sky time actually collecting usable photons.

I replaced the EQ-8 with a Mesu200 about 2 years ago and after the initial setup have lost very few images to mount issues. On the odd clear night I open up the observatory, fire up all the equipment and image without any concerns at all about whether the Mesu200 carrying my qpprox. 50kg imaging setup will perform as expected - it just does. Typically I see guide errors at around 0.25 arcseconds rms with no unexpected glitches, farts or transients.

I can think of no better endorsement of a mount for imaging - the Mesu just works as it should.

HTH

 

Derrick

Thanks for that great overview Derrick.  I think my mind is made up, and rather than kick myself down the road I will invest the extra in the Mesu200 now.

[Astroscot2]

I was in the same position a few years back,  EQ8 or Mesu? -  On paper the EQ8 seemed perfect for that I needed and initially I was very happy with it.

I started imaging with short focal lengths and all seemed fine , the guiding was good and the stars were pin points. It was only when I mounted my heavier 10" newt that the issues became apparent,  the backlash in Dec was a killer,  the amount of backlash would prevent guide star calibration and as I like to dither between subs the mount struggled to re-centre the star before the next sub started.  I tried all the tricks in the book, offsetting the polar alignment, extra weight on 1 axis, even a bungee rope was tried at one point. The last option was to open up the mount and I was not prepared to do that. I gave up In the end after spending an unusual run of 5 clear nights just trying to get good guiding.  So far the Mesu is doing its job with the heavier load, Im still a member of the EQ8 Yahoo group and I don't think much has changed with this mount?

 

Mark 

[RayD]

38 minutes ago, Astroscot2 said:

I was in the same position a few years back,  EQ8 or Mesu? -  On paper the EQ8 seemed perfect for that I needed and initially I was very happy with it.

I started imaging with short focal lengths and all seemed fine , the guiding was good and the stars were pin points. It was only when I mounted my heavier 10" newt that the issues became apparent,  the backlash in Dec was a killer,  the amount of backlash would prevent guide star calibration and as I like to dither between subs the mount struggled to re-centre the star before the next sub started.  I tried all the tricks in the book, offsetting the polar alignment, extra weight on 1 axis, even a bungee rope was tried at one point. The last option was to open up the mount and I was not prepared to do that. I gave up In the end after spending an unusual run of 5 clear nights just trying to get good guiding.  So far the Mesu is doing its job with the heavier load, Im still a member of the EQ8 Yahoo group and I don't think much has changed with this mount?

 

Mark 

Thanks for the input Mark, which seems to highlight a recurring theme.

[Wieben]

I have been through the exact same thoughts.

An almost new 2nd hand Mesu made the choice a little easier. I just got the equipment delivered this week. Dry run in the flat setting up the software. First light should happen soon. So excited. 

On paper I think the Eq8 looks great, but based on the positive reports from fan base of the Mesu, this would be the safer albeit more expensive choice. 

I will post more in a separate tread later.

BTW. Went for the Altair Starbase. Great "engineered" match.

Br. Heine

[kirkster501]

I've likewise opted for the MESU. 

With only small refractors I question why you need a beefier mount than a NEQ6?  My "6" never missed a beat in the three years I had it with my small refractors.  It even worked well with my [very] much heavier TEC140 too.  However, due to a ODK14 ambition that I have next year (and a good bonus ) I thought "now or never" and I sold it with a heavy heart to make way for a MESU. 

My MESU is incoming mid January.  There is a long waiting list building up for a MESU by the way; you don't just phone FLO up for one of these bad-boys....  Who said there is no money about?  £5500 with weights and saddle plate!  No, have not told my GF........!

[RayD]

I think I like the idea of the friction drive, and the fact that in the future I'm probably not going to need to worry about changing OTA or adding kit.  I do also have the 8" SCT, so hopefully this means I can use that more and push it a bit.

Been dealing with Bern at MA today and all sorted.  Delivery at the moment is early March, so that's fine.

Looking forward to getting it, and thanks all for helping me make my mind up 

[si@nite]

Glad you went for the starbase as im pleased with mine, the mesu sits lovely on it