Rainer

1 hour ago, Anne S said:

I'm eventually going to do the same thing with my Cem60 once I've got used to it. I've asked Ian from Altairastro to show me how to do the Dec rotation when I'm at a Kelling Heath next month. I'll post details once I've seen how to do it. I'm worried about damaging the cables as I'll need to use the USB ports for the second telescope camera and filterwheel.

I imagine it'll be similar to your mount but I can ask him if there are any pitfalls if you like.

Hi,

There is absolutely no danger if you take off the saddle and turn it 90° or just ake it off for looking how it is set up.

The DEC head should have slots in order to accommodate the cables coming from the hollow DEC axis. As the mounts have the function Search zero position they have a built in sensor which reads the position of the DEC head and you can only have ONE Zero position.

The same was on my CEM 120EC2 mounts. Unscrew the 4 screws which hold the saddle plate and turn it 90 degrees and you have the double telescope set up possibility and you do not need to take off the stopper screw which acts on the DEC head and NOT on the saddle.

Again, I do not understand how iOptron does deliver such contradicting information being so easy to change it to a side by side arrangement.

On 19/08/2019 at 02:53, Juicy6 said:

Just received answer from iOptron Tech Support:

"You have to remove the stopper and be careful not to over turning it. Yes, you need to remove and rotating the saddle 90 degree in order to make Zero Position Sensor works."

Christer, Sweden

This is an ambiguos answer. The CEM 40 has a built in search position sensor and so if you take out the stopper screw you can not use so you have to turn the saddle around for using the Zero Positio sensor.

Why do they give such stupid answers instead of just saying Turn the saddle by 90° ...

11 hours ago, Juicy6 said:

"this is good question. if you unscrew the saddle means you might modify the zero position. if you turn it 90° degrees it might not work. and if you don´t go for a dual saddle setup but for a classical one, telescope over telescope? The problem is the safety lock..I was having them in my past meade telescope and alway to be careful. also if you risk to to too close to the edge near the stop position, I don´t want you to risk to damage the mount. better to arrange the setup for me.."

WOW 🤔

BTW you can not damage the ount as the steppers just make an awful grinding noise but nothing happens ... It is just not nice to hear them whining 🙂

I have two CEM 120EC2 mounts and have seen the CEM 60EC mount of a friend and they have this stops which act on the DEC head and not on the saddle.

Just tne sure to keep the DEC head pointing to the north and turn only the saddle by 90°, The footpreint of the 4 screws golding the saddle is square ...

My mounts have white arrows on the DEC head and those should point North. That is it. And so the Zero position is correct and you can slew to North and South about +-170°

On 14/08/2019 at 00:21, Juicy6 said:

Morning everyone!

The saddle on CEM40 has internal wiring for 12V and USB2. In order not to twist cables, there is a stop preventing it to turn more than one revolution. What is best way to attach my side-by-side setup scope? Am I supposed to unscrew saddle, turn it 90 degrees and tighten it or should I just define a new home position? Changing position of saddle will move mechanical stop to East or West I guess. Now it is at North, home,  position.

Christer, Sweden

Hi,

Yes that is the solution to unscrew the saddle and rotate it 90 degrees. The stop touches the lower part of the dec head and not on the saddle.

The best is to unscrew the saddle and take a look where the stop is.

Rainer

42 minutes ago, RolandKol said:

As per their Facebook comments, they tested the mount on the pier and used SW tripod to make a picture....

Thanks. I looked at thei webpage but no signs there of that mount .

Now is the admisible load 100 kg with NO counterweights ?

Thanks

5 hours ago, Kaliska said:

 

Is that the tripod which comes for a mount for 100 kg payload ? Looks a bit flimsy to me ... a Losmandy type tripod would be much more adequate, like this one 

Now payload means according to what I know the total admissible weight something can carry  ad in this case it would be Telescope equipment plus counterweights or are they using Payload just for telescope equipment plus additionally counterweights ?

https://www.merriam-webster.com/dictionary/payload 

On 07/07/2019 at 12:41, MakeItSo said:

Simple question for opinions.

Whats the best mount for under £5.5K?

Context:

Will sit in an observatory on a pier

Used for deep sky AP

Will need to carry a 14 inch SCT OR a 130mm refractor plus imaging kit.

(not both scopes at the same time)

Portability not important

Weight capacity is important

Accuracy critical

Ease of set up and use very important 

 

Hi MakeItSo,

Any updates ? 🤔

Rainer

40 minutes ago, MakeItSo said:

Hi Rainer,

how easy are those mounts to set and use?

Hi,

As easy or as difficult as any other Ecuatorial mount brand.

Do you have experience with an Ecuatorial mount ? If yes then you have nothing to be afraid of. I am 66 years old 168 cm short, not in good shape, and managed to lift up the mounts onto both of my piers and they are high, one is 1.65 meter and the other one 1.55 meter (measured to the top of the aluminum plate). The mount weighs without counterweight shaft about 26 kg. The CW shaft is about 4.5 kg.

You set it on your pier. Level it as best as you can. Adjust your North pointing by moving Azimuth and altitude hardware adjustements. They are quite precise. Azimuth has a 3' arc minute scale and Altitude has a 0.5' arc minute scale and once set up the position are very accurate for repetitiveness.

If you better post your specific doubt it is easier for me to answer.

I have both drift aligned with the Guiding software PHD2. I tetsed Polar ALignemtn with SHarpCap and aslo have a QSY PoleMaster. While they also align your mounts the best accuracy is with Drift Align. OK, you need to invest time for Drift Align but being permanent in an Observatory you perhaps will check Alignment every 4 or 6 months.

Having encoder on RA makes you guiding more comfortable as you do not deal with Periodic Error and just correct for Polar Aligment drift and Atmospheric refraction drift and NO encoders are not for unguided imaging 🤨 IMHO. OK you can make unguided images but after a session of 3-4 hours you will see drift in your images getting worse the nearer you approach the horizon.

Just ask and I will try to answer your questions.

JMHO and YMMV

Rainer

Hi,

I do not know the CGX-L nor the Skywatcher EQ 8 but I know for sure the Losmandy G11 and the CEM 120EC2.

Do not touch the Losmandy G11GT as the backlash problem is not solved here. Believe. I did fight with that for the last 16 years 😎 I even invented a floating worm systen for the G11 15 years ago.

Now since Novemeber 2018 I installed two iOptron CEM 120EC2 mounts inmy observatory and I could not be happier. 

On one mount I have a Mewlon 250S side by side with a SKY 90 as well as a FSQ 85ED and the counterweight shaft carries 54 kg of counterweights.

I do not know how much your SCT 14 weighs and the 130mm + all other but I would bet that you can set it up all on a CEM 120. I would get the EC model and if you can afford it go up to the EC2 and you are done for the rest ? of your life ...

I do not recommend exchanging too often the telescopes ...

But as always I am stronlgy biased toward iOptron and is JMHO 🤔

regards Rainer

deleted

On 24/06/2019 at 20:06, Chris Tardif said:

My questions are do I buy the forever mount (CEM60), the cheapest mount (EQ6R) or the newest mount (CEM40).

Hi Chris,

I am strongly biased but I would go for the CEM 60 and if the money does allow go for the EC version.

Rainer

3 hours ago, Chris Tardif said:

Nothing like being late to a thread, but in my quest for a new mount (still undecided (CEM40, CEM60, EQ6R-Pro)) I found a graphic that shows how the capacity of a mount falls off as the diameter of the OTA increases.  It lives here: https://astro-physics.com/mach2gto 

I would think that all mounts would behave in a similar manner.

 

Hi,

That is a nice example of how to specify the real carrying capacity of a mount 👍

What are you going to mount on the new mount you intend to buy ?

Rainer

On 16/05/2019 at 04:26, Stratis said:

Hi all,

Coming back to astro after a long break, many ups and downs  

I recently hauled my trusty CEM60 out of limbo and realised I'd like to shift to a smaller mount, as I have never come near the incredible weight limits on this mount for imaging or visual. The new CEM40 really looks perfect in most regards, so I am hoping that will serve as my new main imaging mount. I image with apo refractors, from a 7kg 115mm TS triplet down to a little WO Megrez 72 at only 2kg on an AstroTrac, with both DSLR and QSI 583wsg (so about 2kg camera package). My greatest imaging load has never exceeded 12kg.

I already have an amazing Avalon T-110 T-pod underneath the CEM60, with an iOptron adapter atttached, this one in fact: https://www.teleskop-express.de/shop/product_info.php/language/en/info/p10799_Avalon-T-Pod-110-130-Adapter-Kit-for-iOptron-iEQ45-and-CEM60-Mounts.html

This adapter has the central peg for iOptron, plus mounting holes set around the perimeter for the alignment pegs. The adapter has two sets of two threaded holes; the first set is 130mm apart across the centre, and fits the CEM60 perfectly. The second set is 120mm apart across the centre, and I think is meant to fit the smaller iOptron mounts like the iEQ30. 

So the £1400 question; can the adapter accept a CEM40 mount? Can the two threaded holes set 120mm across the centre mate with the CEM40? If anyone has any info on the absolute mounting hole arrangements for the CEM40 alignment pegs it would really help  

Hi Stratis,

Any news about your project about downgrading from CEM 60 to CEM 40 ? 😲

Rainer

29 minutes ago, Nigella Bryant said:

The only huge momentum would be while slewing to an object,

For me that is not a problem.

But are you sure a Dome inhibits Air Currents ? I have never had a dome but the wind gets in everywhere ¿ or ?

Rainer

1 hour ago, Nigella Bryant said:

An f4 I think 1558mm in length. 5ft 3in in old money I think. At the mo, my 12inch f4 is 1200mm or 4tf.

OH I see quite long telescopes and ehre the weight is not relevant but the moment arm and how much it acts as a sail ...

Maybe a Truss Newtonian and not a tube Newtonian ?

Hi Stratis,

Is this what you want to load on a CEM 40 ?

https://www.teleskop-express.de/shop/product_info.php/language/en/info/p3041_TS-Optics-PHOTOLINE-115-mm-f-6-96-Triplet-APO-with-2-5--RP-focuser-1-11.html

If yes, I do not recommend to go down to a CEM 40.

Weight is not everything. Moment arm is more important then total weight ...

There is a big difference between a cylinder 40cm long weighing 7 kg or a cylinder 100cm weighing 7 kg. Both have the center of gravity in the middle but the moment arm exert totally diferent forces on the mount if 40cm or 100cm at the same weight ...

You can test it your self. Take a 40 cm long stick and move it rotational back and forth and take a 100cm long stick and do the same ...

regards Rainer

27 minutes ago, Nigella Bryant said:

next year to upgrade to a 16inch newtononian

Hi,

How long will that Newtonian be ?

Rainer

2 hours ago, DaveS said:

Oh, I'm not decrying the CEM120, just saying that the DDM mounts would probably be stopped from hitting those limits.

For what it's worth, if I hadn't bought the DDM mounts then the CEM would be at the top of my short-list. Mind you, having grown used to the utter silence with which the DDM slews, hearing gears whirring is a bit novel.

Yes at 4° per second = 960X the CEM 120 is a bit noisy but at 512X ~ 2.13° you do not hear it anymore ...

Of course that is very annoying when slewing once per night to find the object to be photographed  🤣  for 4 o 5 hours and then another slew for parking 😱 ... a bit of fun must be allowed ...

Unfortunately the GoT speed can not yet be adjusted and is done always as 960X ... has been suggested to iOptron already ... 

14 minutes ago, DaveS said:

I'm not sure the ASA software would allow you to do that, but in any case there are no gears, wheels, belts etc to break.

... and good for the ASA mount owners like you, who do not have to worry about that, but as you know Mr. Murphy is out there and in the least thought moment he plays you a trick ...

There is no product which is 100% fool proof ...

You are right but the purpose was to demonstrate that the mounts are robust ... No more no less ... 

Also as there are many Urban Myths out there complaining about so called Mass Produced Chinese Mounts are rubbish and delicate ... specifically because they are not machined out of a block of Aluminum ...

BTW the CEM 120ECXXX are not a mass produced product ... but there is still the thinking of the people that anything made in China is MASS produced ...

2 hours ago, Nigella Bryant said:

I'd only be looking at the non encoder at what I can afford but with guiding would that still be good if it's not 100% beta tested. I'm really taken with the Cem120. 

Hi,

As far as I can judge the CEM 120 Plain Vanilla is as troublefree as any other mount and as written ... where do you get that carrying capacity for that amount of money ... and believe me ... the mount is robust

https://vimeo.com/277888636

https://www.youtube.com/watch?v=KsHkzgjPYGA&list=UU-Y3S_VW6ek5nBOkoeiUZ_w&index=9

As you can see nothing breaks and NO, I did not loose the 2 Year Warranty by doing that 😱 or at least iOptron has not told me 🤔

So far I have not seen a video by somebody doing this with a so called " Premium Mount " like Astro Physics, ASA, 10micron, Paramount, you name it ... 😎

Rainer

11 hours ago, Nigella Bryant said:

Cus in light polluter skies more shorter image's stacked are better than less longer one's. I saw a convincing talk on this recently. 

Hi,

Understand and I guess it is all a question of what objects we do image.

I asked because I image from a suburban sky and make 900 second exposure time images.

I have two CEM 120EC2 and I would say it is the best investment ratio so far. 115 lbs carrying capacity (no counterweights included in that ratio, to added to it) for each US $ 6.998,00. No other mount brand has a carrying capacity including encoders for that  price.

The Plain Vanilla CEM 120 is US 3.998,00 which is also inbeatable.  You will not find a mount with this carry/price ratio. Perhaps the Skywatcher EQ-8 ?

OK the mount is out now for about 18 months but I know as having beta tested a lot for iOptron that the mount is ripe to about 95%. Mechanically the mount is very robust (OK, the USA market does not like injection molded parts) perhaps because they are not shiny and you have no bling bling moment 🤣

The base model CEM 120 ist I would say 99% ripe. iOptron Customer support is first class.

As you see I am very biased but also very satisfied with my two mounts and they carry a lot.

Rainer

PD Look where I am 😱

On 12/05/2019 at 01:44, Nigella Bryant said:

I can also do unguided images for 45 to 60 secs which is enough in Mt light polluted sky.

Hi,

Why do you limit yourself to this exposure times ?

Rainer