teoria_del_big_bang

1 hour ago, souls33k3r said:

Another vote for CEM60. I had the EC version and had nothing but issues with it. It wasn't a mechanical thing, it was a firmware thing but I can't wait on the company to produce better firmwares so went down the vanilla CEM60. Another thing to add is that the weight of the CEM60 is so much lighter than the NEQ6 Pro that I had. That thing was built like a tank but that's not to say that CEM60 is not quality finish, it screams quality at your face. 

If I had money to burn, I would've gone for MESU 200 myself but then I also like to travel with my mount so yeah the decision for me was easy. Hope this helps

Yes helps a lot thanks. I have always liked the look and the functionality of the IOptron mounts but as put off with a few horror stories of issues with them but maybe this is the more sophisticated units, like you say with firmware. Maybe the simpler CEM mounts are fine, certainly the CEM60 seems to get a lot of good reviews. 

Steve

2 hours ago, Wiu-Wiu said:

With an EQ mount I was able to move far beyond the equator when imaging. 

(I should specify I rate mounts by their use in astrophotography, not visually)

the cem has 2 options: “at x degrees beyond equator: stop, or flip”.

i have never taken the flip option. This limits my imaging time on a single image per night, which I do not like. 

I have yet to find software that handles a perfect meridian flip and continues. With an apo, I would consider that. With an sct... not that much...

Thanks for the explanation.

With my HEQ5 most sessions I flip anyway using APT and seems to work like a dream. First couple of times I tried it I set my alarm to get up before it as APT tells you exact time it is going to do the flip and watched it as I was worried but all went fine. It does a plate solve just before the flip then again afterwards to ensure it is in the same spot almost exactly. Yes you have images 180 different but then PixInsight takes care of all that so  you don't have to do a thing.

So I am guessing that should go the same way with a CEM, I hpe anyway.

Steve

Thanks for the advice @vlaiv I am now looking more seriously at this option. Although I was not looking for a 60lbs payload the actual weight of this mount still makes it possible to move in and out of my garage so that is not restrictive in any way.

The more I read up on this mount the more I am beginning to like it, the way it balances, the way the worm gear works etc. Not sure about the so called internal cable management as the USB looks to be only USB2 which might not work with the 1600 camera too well.

This is certainly a candidate now.

Do you think then that this is a better way forward than a smaller mount with encoders?

Steve

This looks a very interesting project, good luck with it.

Steve

10 minutes ago, Wiu-Wiu said:

I second the CEM60 idea. I had an IEQ45 and while it is an excellent mount, it was quickly too light for my never ending aperture fever. It handled my 127mm apo triplet quite good, but the Esprit 120 was too much. Anything equal and less than that, and the ieq45 will be an excellent candidate. I think your Esprit 100 might be on the limit too.

The CEM60 is a whole other league. But you will have to cope with the meridian flip. For me, that is the only downside to that mount. I have sold the IEQ45 and if I buy another mount, it will probably be another CEM. 

The Esprit 100 is certainly on the top limit for the HEQ5 but I think is okay for the IEQ45 according to the specs.

What do you mean by having to cope with the meridian flip with the CEM60, is that any different to the flip with the HEQ5 (excuse my ignorance here this is the reason for getting as much info as I can before paying what is probably my biggest single outlay so far 🙂 )

Steve

11 minutes ago, vlaiv said:

Any reason for not considering CEM60 (non EC version)?

Probably my lack of knowledge. I had looked at this, and with a tripod or the tri-pier which I quite like would be within my price range but upper end.

It is bigger payload than I was thinking of but I have not ruled out an obsy build for my retirement so that would fit the bill.

I think rightly or maybe wrongly I had thought if I do not need such a large payload then the money was better off spent on something with encoders for accuracy (or am I mislead here ?)

Steve

As I am due for retirement next year I am thinking of investing in a new mount while I still have some cash coming in. 

I currently have a HEQ5, belt modded which works well but whilst I do not have an unlimited budget would like something with a bit more payload and accuracy regarding tracking.

I would say my comfortable budget would be around £1500 to £2000 (assuming I will sell the HEQ5 for say £500) but would stretch it a bit more if the benefits were there.

My current thoughts for a while have been either :-

Sky-Watcher EQ6-R PRO Go-To Astronomy Mount

Sky-Watcher AZ-EQ6 GT Pro GEQ & Alt-Az Astronomy Mount

BUT, I know this is double the price but are there significant benefits to something in this price range

iOptron GEM45-EC German Equatorial GoTo Mount with RA Encoder

I have read quite a few reviews on all these and really not heard much bad said against wither SW mounts, although most reviews do consider the price and do add "for the money" which is fair enough as they are very reasonably priced, and whilst the IOptron does look to be a step up in manufacturing quality I have read some alarming reports about IOptron mounts failing.

I would be most grateful for any advice on the above OR other mount suggestions (but under £3000 at least).

Steve

If there is room to fit the filter drawer then yes you should be able to do so. Don't forget to add 1/3 of any filter thicknesses in path after flattener, including the LP filter in the flattener itself (if you have added one).

Steve

I think the canon T mount thickness should be 11mm which combined with the 44mm distance from sensor to camera mounting face makes up the 55 mm. But worth checking the t Mount you have is actually 11mm.

Steve

I am a little confused because yes everywhere I look at the Flat61A is says adjust to 12.9 mm but there is a back-focus drawing that sort of says 18.10 mm.

I am assuming this is an old drawing and is for the original flattener that was not adjustable. You cannot be over 5 mm out otherwise there would be more than a bit of coma.

Have you got a filter in the flattener ?

If so then on the adjustable flattener the filter is the camera side and so needs to be accounted for by adding 1/3 thickness of the filter. Depends on your filter but they are normally around 3mm so you could be 1 mm out.

Steve

27 minutes ago, masjstovel said:

@Ishan Mair i am still not 100% satisfied with my problems yet, but i dont mind at if you're posting about your problem too:)

I might have a sollution for you.

In Martin Pyotts videos on youtube he mentions the exact problem you describe. Its a common mistake that the whole brass-wheel gets greased, when its just the teeth that need greasing. Symptoms when greasing the whole part, is as you describe: The clutch dont brake very well.

I too had the problem like you, just not as bad as you describe. When i did the supertuning there was alot of grease on that brasswheel where the clutch grips (factory grease - 2nd owner but saw no signs that the mount had been disassembled before), which i removed. Now the clutches grip very well. 

Never thought of that, but yes that could cause the issue.

Steve

Ishan,

I am not fully sure what you mean, but those taper roller bearings are there as thrust bearings and as I said above are there to stop any movement in the direction of the double arrow on my very crude drawing. There are other bearings there to take care of the rotational movement. Certainly do not leave them so loose that thee is any chance of movement in that direction and  possible a small amount of nip to give some pre-load but really not very much. By all means use some sort of tool on it I am not saying only use your hands as it is difficult to turn a castellated nut by hand but I use the expression hand-tight to convey the sort of force to apply when tightening.

Also how free it rotates should only aid the balancing because to balance well if it is tight at all then there can still be some small out of balance but you will not see the axis move.

However, neither of the above should have anything to do with the axis slipping when the locknut is tightened. I would say something is not set right with that or something missing. Make sure the brass button is there under the locking screw, also ensure the screw is wound in enough before screwing on the lever, from memory you need to screw the screw in till you just feel it start to tighten up then back off about 1/8 turn and then fit the lever so that 1/4 turn or so on the lever totally lock the axis in place. But make sure the brass button is there otherwise you will damage the spindle with the end of the screw.

See here:-

heq5-rebuild

Steve

Maybe this can explain better than I could:

How Telescopes Work

Also some good answers on this old thread:

slow-scope-fast-scopewhat-does-it-all-mean

Steve

I only took up astrophotography about 14 months ago so my advice is nothing like as useful as some of the advice given above.

But what I would add is that it is not an easy hobby and there is an awful lot to learn to get a good image. I too started out by asking advice on this forum about a setup to do both planetary imaging and DSO's and was heading down that route. But when I started to get advice and also read up on both of these they really are two very different things and require different kit (Ideally). Also techniques are different.

So after much thought my own decision was to pick one and concentrate on that. My thinking was that for one learning both would be harder, also whatever I buy will be a compromise and sooner rather than later I am sure I will regret it and end up buying a scope suitable for one or the other.

You have a DSLR which is great as it saves a lot of expense but again at some stage you may well will find yourself wanting a dedicated astro camera and whilst there are ones suitable for both, again it will always be a compromise.

I think what I am saying it was my point of view anyway that it is better to be good at one (or at least as good as possible) rather than struggle and maybe get okay images of both.

So I chose DSO's but I always though that when money became available and in the near future I would also buy some planetary gear. I did get a camera 2nd hand but to be honest I have found there is always so much to improve on your techniques and also just so amazed at what is out there regarding DSOs and even those are not all the same and require different approaches that is more than enough for me at the moment.

If you are absolutely sure you must do both then fine but have a real good think before you buy 🙂 

Also you have the camera put at least half your budget, or more, into a good sturdy mount. I have often heard that you can great images from a fairly cheap scope (especially 2nd hand) but will struggle and you will get frustrated with a poor weak mount.

Steve

Yes those are the bearings I meant.

They only need to be tight enough that the rollers are always in contact with the race. So I would not say make them loose but it is very east to over tighten them when using tools to tighten them. But unless you are a body builder then I would say it is difficult to over tighten by hand, but do not leave them loose at all.

I do not know if you followed this guide but it is worth a look.

Astro Baby Guide to EQ6 Stripdown

This actually shows tighteneing with a tool but stresses not to overtighten. I did not have such a tool at home so I think used two allen keys in the grooves of the nut and then just tighened by my hands.

Essentially they need very little pre-load, if any, you just need to sure there is no movement at 90 degrees to the bearing (I hope that makes sense). See my very bad quick sketch below.

I guess temperature can make a difference as when very cold I guess the pre load will go up a bit due to the spindle contracting, so I would say if hand-tight at normal room temperature (20 C or so) then they may get a bit tighter when nearer to 0 C but not by much so would be fine they are unlikely to get looser.

I tried to look at the video but I am currently working in China and the internet is really slow despite my VPN so the video is really not easy to watch or download so difficult for me to comment. Just make sure the axis is not stiff at all and that there is no movement as shown above.

Steve

I fitted new bearings and added the Rowan belt mod to my HEQ5 and assume yours is similar.

The aligning of the worm in Ra is very tricky. I too made it so thee was no backlash and all seemed fine for a while then when I mounted my scope the motor stalled every so often. It took me quite a while fidlling with the two grub screws to get the motor to work without stalling and have the least backlash. Basically I just kept adjusting then moving Ra through the full 360 degrees a few times at full speed to ensure no stalling, when I adjusted it too much so the motor first stalled I then just backed it off ever so slightly and it has been fine since.

I have only owned one Skywatcher mount and as an engineer they are great mounts for the money but are not perfect by any means. I would say all of these mounts to some extent will have some periodic backlash to these gears. They are not perfectly manufactured and there is some cyclic tight spots within this worm gearing so you can set it so at the tightest point there is little, or no, backlash but then as the worm turns it will get less tight and there will be some small amount of backlash.

Points I noted on my HEQ5 (so not sure if exactly the same) are:-

• Do not over-tighten the thrust bearings or the taper roller bearings, I found literally just hand tight was enough. Too tight and that also puts extra load on the motor.
• Take time over setting the worm backlash it is a lengthy job to do right and it will never be perfect.
• With the Rowan belt mod it is even more important to precisely balance your scope.

Regarding the periodic error you will have due to this worm I believe there is something you can do to at least make it better, although as a relative newbie to all this have not done it myself and it is called PEC (Periodic Error Correction).

There are quite a few threads about this (here's one I was looking at recently)

using-pec-with-heq5phd2

Like I say I am relatively new to all this only been imaging for around 14 months and I didn't get a lot of chance to do it anyway due to work and the UK weather 😞 so this is only my experience to date and hope I have not said anything misleading. I am sure some of the many experts on this forum will correct me if I have.

Good luck with it 🙂

Steve

Fantastic image 🙂 

Steve

I can on reiterate what is being said above, by anyone's standards that is a cracking image with great detail and superb colour.

I think if you look around there are always other images about, on this forum alone, that you will consider better than yours (I think we all are generally very self-critical) but an image like that is definitely something to be proud of 🙂 

Steve

Bryan,

Superb image, absolutely nothing about it I do not like, colour and detail are just great 🙂 

Steve

That is one special video from a very special place. absolutely fantastic.

Steve

Yes I had quite a few night trying to get to grips with guiding and not getting any worthwhile subs. But for sure it cannot be considered as wasted I am sure we all have been through something similar. I find it hard to believe anyone has clicked on PHD and guided to perfection just like that.

So I think 3 nights fiddling about is not bad at all.

Steve 

Even a 1 amp fuse in the mains plug means the unit could still deliver well over 10 amps at 12V.

If the supply was 100% efficient then in theory a 240V supply could supply around 20 amps at 12V.

Now nothing is 100% efficient, far from it and there is maths involved when converting AC to DC but for sure a 1 amp fuse would not necessarily prevent this.

A 1 amp fuse in each output to the dew straps would be the best  thing to do.

Steve

I know I am talking small flexible couplings here but I have worked in Engineering for over 40 years that use flexible couplings and some small enough to suffice for this application. The flexibility it up/down and left to right, there is no rotational flex at all. We work to under 2 micron precision for size and for angle +/- 0.01 degrees so if we use these for our absolute encoder feedback in the loop of our servos there can be no angular error.

I agree some alteration to the design to account for the bigger diameter coupling would be necessary but stand by the fact they would still be an improvement. 

Steve

4 hours ago, Kev M said:

I have been trying to obtain a polar scope cover for an HEQ5....with no success.

However I have came accross this from someone who must have had the same problem.

https://www.thingiverse.com/thing:2806098

Is there anyone with the skills and equipment to print one of these off....I have neither....😫

I would be more than happy to reimburse for materials and a bit extra for labour etc.

As well as immense gratitude for whoever could do this.

Kev

 

 

Funnily enough I do not use a polar scope as I have a Polemaster fitted and was annoyed at the small amount of movement I could get on the altitude bolt at the back of the HEQ5. I littrally could get just 1/2 turn when the cap was in place. and had to unscrew the cap to be able to turn it properly. So I removed the polar scope and designed a shallower cap and printed it so I now do not need to remove it.

So I would willingly print you one of these but unfortunately I am now working in China until just before Christmas.

But if nobody else offers by the end of the year I will give you a late Christmas present, PM me after 18th Dec if you do not have one by then 🙂

At this rate I will have my own business going by the time I retire in March 2020 🙂 

Steve

4 minutes ago, Pompey Monkey said:

Agreed!

There is so much negativity and hate going on online.

This is a smashing haven for the sane and well-meaning.

Absolutely, although I totally agree with the well-meaning you may be on dodgy ground mentioning sane (well for some of us anyway 🤣 )

Steve