Swag of issues with setup...help needed

[dpastern]

OK, I'm not sure if I should have posted this in here, or in equipment. Mods, move as you think is needed.

OK, I have a swag of problems. I'll go through them in order, any help/comments etc are appreciated.

1) Focuser keeps slipping when my camera is attached. Said camera is a Canon EOS 1D Mark IIn (about 1.5kg, including battery). I have tightened what I believe is the focuser tension bolt, see the image in the following link (I've circled it Red).

http://www.macro-images.com/web/astro/probs/focuser_adjust.jpg

It made a difference for one viewing session, which was a week and a half ago. My viewing session from Monday night was horrendous - the focuser started slipping immediately. I basically cannot focus in past a certain point and have to place physical pressure behind the focuser unit for it to 'grab'. I would not expect this to damage the focuser, but please let me know if you think it will (and why). Worse, I cannot reach focus with the camera at all. Now, it's worked in the past, and I cannot see why it stops working to be honest. I can only suspect that something internally is slipping.

I also use a Williams Optics 2" diagonal as part of my usual setup. I removed that, and tried to focus with the DSLR directly attached to the OTA's focuser - no go. Could not reach focus with the camera. I tried moving both the WO diagonal in and out a bit, and same with the T adaptor, no luck. It's not dew on the sensor either - I put a 50mm lens on it and checked and no dew in sight. I could reach visual focus with just using the diagonal & eyepieces. Below is an image of the moon at best focus - very badly OOF (out of focus) as you can see.

http://www.macro-images.com/web/astro/probs/oof_moon.jpg

It is becoming increasingly frustrating and I'm really tempted to talk to Lee @ Andrews and see if I can maybe swap the Equinox out for a Williams Optic Megrez 90, or something that has a better focuser. I believe some CCD cameras weigh 1.5kg or more, so if the scope's focuser can't handle this, it's not much good to me down the track. It has worked in the past, so I *know* the scope (and focuser) can do it. I cannot see why it is failing to be able to reach focus. The drawtube correctly goes in all the way and out all the way, so unless it's an internal problem, I cannot fathom why this is happening. After the first set of problems with the focuser, I didn't use the setup for around 6 or so weeks as I'd lost heart in it all. I ended up tightening the focuser and the next time I tried the camera, I had no problems. Surely the camera can't keep continuously causing the focuser to slip?

2) Said WO diagonal is very very tight to fit in the Equinox' focuser - and I mean *really* tight. I have to physically force it with quite a fair bit of strength for it to go in. Removing it is even more difficult imho. I do not believe that this is right. It has always been like this.

3) The rotating collar on the Equinox unit is quite stiff, and very difficult to tighten and lock (and loosen for that matter). I basically have to put enough force behind it so that the OTA moves. More on this later. I have tightened and loosened it quite a fair bit in order to try and ease the stiffness, without much luck.

4) On Monday night, when trying to loosen/tighten the collar mentioned in 4), and rotate the focuser/diagonal, the OTA moved in the dec axis. Now, I had the dec axis locked, surely it shouldn't have moved? Could this cause problems with the mount? If so, how & why?

5) As I was about to give up on the night, I decided to tell the mount to go back to the parking position and turn it all off. The EQ6PRO mount made a horrendous grinding noise, far worse than usual, 3 or 4 times as loud and was moving very slow, probably a quarter of it's usual speed, if not slower. I noticed the battery's charge LED was flashing. Worse, the mount parked the scope completely upside down, much to my dismay, see image below.

http://www.macro-images.com/web/astro/probs/incorrect_parking.jpg

I presume that this was due to the power from the battery draining to a point where the mount could not operate properly. Could this have possibly damaged the mount? There was no warning with this, and the charge LED was solid until the problem hit. I left the light on the battery to drain the rest of the power so I could recharge it. See point 6)

6) I went to charge the battery (Celestron Powertank 17) and it refuses to charge. I've tried several known working power points to no avail. The charging LED does not come on at all. Unit is like 4 months old, used maybe Six times. If I haven't used it for 3 or 4 weeks, I've completely drained it before recharging it, as per instructions. I presume the battery is faulty and dead as a door nail. I've rang the supplier (York Optical) who expressed surprise at this problem, indicating that they'd never seen/heard it happen before. Interestingly, research on the web (thanks Google) shows that this is a common problem. I suspect said retailer didn't want to admit that ;-) Why did I purchase it from York & not Andrews? Andrews didn't have any batteries in stock at all when I purchased the mount/OTA/accessories etc. York was the only one that had something in stock at the time. edit: If the battery has damaged the mount, then I believe Celestron is liable to pay for repairs to the mount. I've followed all operating instructions to the "T", it's failed without warning. What are your thoughts on this as consumers?

7) I ran CCD inspector on an image that I took of M42 when I first used the scope, to try and determine field curvature etc. If I'm reading the graph right, there's moderate field curvature, and the scope is badly collimated. Edit: I guess this could be curvature in the DSLRs sensor (that isn't very good if that's the case), or more probably, the T adaptor/camera were not aligned correctly in the focuser tube. See CCD inspector images below. I've also included the original M42 image for your perusal.

http://www.macro-images.com/web/astro/probs/ccdinspector.jpg

http://www.macro-images.com/web/astro/probs/ccdinspector1.jpg

http://www.macro-images.com/web/astro/probs/_DN_1977pp_cropped.jpg

This is a simple 30 second exposure, one shot, no stacking. Very rough polar alignment as you can see. In fact, it's the best I've managed out of Six or so attempts...despite totally guessing due South on my very first attempt (and being quite out, at least if my Solar noon calculations are anything to go by).

If the scope is not collimated, how do I adjust it? I don't see any adjustment screws at the front element of the OTA, which is what the SkyWatcher manual says...

8) I'm not even going to really discuss polar alignment problems in detail...despite quite a fair bit of effort, it's not even close and I'm going backwards with it all in this respect imho. I do suspect that my alignment due South is better, but the latitude adjustment is way off due to the mount's inaccurate latitude markings. I'm working on getting an electronic inclinometer, which should hopefully help solve that problem.

9) I'm not able to get the scope to balance properly with the DSLR attached - even with the scope and dovetail as far forward as possible. This is in the dec axis. RA axis balances fine as expected. I'm not sure what to do to combat this problem...

Sorry for such a long post, but I have so many problems, and I'm getting extremely frustrated with it all. That frustration does nothing for my health, nor nothing for my enjoyment in the hobby.

I do not have a car, so I'm not able to take my gear to meet ups etc. If I had a car, that'd be the first thing I'd do. If people in the Brisbane area want to pop in and see me, they're most welcome to PM me.

Thanks in anticipation.

Dave

[madwayne]

Hi Dave

I can feel your pain and am sorry to hear that things aren't working for you.

Firstly what is the telescope you are imaging with?

What is the other thumb screw just in front of the one you have circled? From memory the front one is the one that locks the focuser in place, the one you have circled is the one that adjusts the tension within the focuser when you are racking the focuser in or out. At least that is how the 10:1 GSO focuser works on my ED80 from memory, seldom touch mine as that way I don't have to re-focus.

If you are happy with the telescope you have don't get rid of it simply upgrade the focuser, mind you it looks like quite a nice focuser for what you are doing.

Low voltage will do what you described. The way I work my EQ6 is once that power light starts flashing it is time to park the scope and load it up with some fresh battery power. The other night at home I was tinkering with my EQ6 and the battery was on it's third night without charge. I was inside watching the scope slew from Sirius up to M46/47. It went from Sirius up to M46 then back to Sirius then back up to M46. Took a look at the power light sure enough it was flashing. Parked the scope, changed the battery pack over and it worked well for the rest of the session.

As far as the pack not holding it's charge, I would suggest it has died. I'm no battery expert, others on here should be able to better explain the reasoning as to why it has died. In fact I think it was on this site that I read something about not running these battery packs completely flat.

In answer to your balancing question how about some sort of magnet at the front of the OTA. Or is the imbalance that big?

Good luck with it all. Please hang in there, keep asking questions and I'm sure one of the kind folk from Brisbane will be along soon to offer a helping hand.

Wayne

[troypiggo]

G'day Dave,

I was going to set up this weekend to do some testing etc, but just remembered as I type this that I have a 40th to go to. I'd rather be imaging :)

I can't come around in the next week or 2, but keep me posted if you continue to have problems or if you've solved them. Can't help with the powertank issue, but can help to look at the focuser, balance and your polar alignment etc.

[toryglen-boy]

Sorry to hear your not having a very good time!

Most scopes (except the really high end stuff) come with a 'standard' crayford focuser. Not that its a bad thing, but they are primarily intended for visual use, and TBH when most people get into serious imaging, they tend to change the focuser as one of the first steps, alot of the quality replacement focusers come with a weight rating as to what they can happily accept, and they are built beefier. I use an Orion ED80, and i am luck, as in the person i bought it from, sorted the focuser right out, so if it wont stay, then look at replacing it, i am sure the experienced imagers on here can point you in the right direction.


As for reaching focus, this is always hit and miss, with my Orion ED80 i can ONLY focus the shot with the camera attached via the T-ring and it wracked out, visually it will only really come to focus when using a diagonal.


not much,. but i hope it helps

;)

[marki]

Dave, one bolt locks the focuser and the other adjusts tension. Have a play with both with the scope off the mount. Sometimes tightning the bolt will release the tube allowing it to move independantly off the adjuster. On my ed80 which had a similar system the bolt had to be fully undone to get any grip. The rear bolt adjusted the tension and the front bolt acted as a lock. Got a moonlite on it now and that fixed all the problems.

Mark

[RobF]

Are you sure the Powertank says to drain completely before charging David? That sounds more like old NiCad instructions. Usually these sorts of things contain SLAs (sealed lead acid), and you want to take out as little charge as possible each use, then recharge as quickly as possible.

If it is SLA, would be best to get it on charger and leave there as long as possible. Failing that, it might need a smarter multi-stage charger to kick start it back up over the min point at which basic chargers will start to work.

[dpastern]

Thanks for the replies guys, much appreciated.

It's a SkyWatcher Equinox ED100 refractor. The circled bolt is, I believe for adjusting tension, and yes, the other one (silver coloured) is for locking the focuser. Well, that's what I've come to the conclusion of ;-)

I'm glad someone else has seem similar behaviour from a mount and when a battery is low...

Rob - you are absolutely right...my bad, looks like I've probably damaged it then :-( I'm sure I read somewhere to completely drain and charge...oh well. I'll take it into York Optical and keep my mouth shut and hopefully it'll get repaired free of charge. They make enough money on the damn units as is imho. My dad has a normal battery charge, could be worth a shot I guess. I'm more worried about long term damage if how I've been recharging it is wrong :-(

Mark - yeah, that's what I've been doing. I think I've been forgetting to lock the focuser when the camera is attached, so gravity and a weak (imho) focuser unit have conspired against me. Still, tightening the focuser back up again should resolve the focus issues...it still doesn't explain why I can no longer reach focus at all with the camera attached.

Duncan - it's a Crayford style 10:1 focusing unit, you are correct. Focus seems smooth and I'd read good things about it before buying...maybe I got a dud, I don't know.

One thing I'm suspicious on, is that I'd told Andrews that I'd buy the Equinox (last unit, demo model). Right at the end, after I'd placed the order, but before the money had cleared and the items had shipped, I changed my mind and asked if it was possible to get a Williams Optics Megrez 90 instead (primarily cos it looked sexier and had faster optics). They told me that they had none in stock. A few days after I got the unit, they updated the website indicating that WO Megrez units had arrived. I have a strong suspicion that they wanted to get rid of this model, maybe they were discontinuing this range, I don't know. Maybe I'm just being paranoid. I just checked, they no longer stock Equinox units. Interesting.

Also, I tried to talk them down in price but got nowhere, in fact, they put it up by a $100 between me committing to buy the unit (via EMail) and depositing the money, which was over a period of a week. I was basically waiting to get paid...their reasoning was the dollar crash. I tried to argue that they bought the units before the crash, so the crash didn't effect them at all, at least with this scope, but he would have none of it. So, in hindsight, I feel a bit dirty about it all. I haven't really dwelt on it though, better things to do with my time. This is the first time that I've really given it all a 2nd thought since I bought the gear.

Troy, would be good to meet up again. Bring along some snags and a steak and I'll fire up the BBQ :-) Bring the missus if you want.

It looks like I'm going to be out of action for a while though - York Optical said that they've changed distributors and it takes longer to get the units looked at/repaired. Not a happy camper am I! I hate being a newbie sometimes...

Thanks again for the help guys, much appreciated.

Dave

[marki]

Dave you shouldn't have to lock the focuser only when the thing is straight up and down and then only if you have a large payload or a crappy focuser. Must admitt I am a little confused about the focus problem though especially since it used to come to focus. Does it still have full travel or is something stopping it moving all the way out?

Mark

[dpastern]

It has full travel in and out...that's the odd thing. Externally, it looks fine. I can only think that it's an internal issue of some sort. But - after I tightened the tension lock up on it nearly 2 weeks ago, the next time I used it, I was able to reach focus again. The inability to reach focus seems related to the slipping problem. Maybe I don't have enough tension on the focuser drawtube, hence it doesn't have enough strength to hold the camera in place. Remember, the camera is 1.5kg, so it's not light. But it doesn't seem much heavier than a CCD imaging unit, either, so that sort of makes me think that the focuser in this unit is faulty, or I simply have it too loose. I'm going to have another look at it on Saturday and test everything again.

Did you check out the ccd inspector images as well? I wonder if I'm reading them right - if so, the OTA either is badly miscolliimated, or the sensor on my DSLR isn't very good, or I haven't had the t adaptor squarely inserted into the focuser tube. Or, all of the above ;-)

Oh well, time for bed...

Thanks again.

Dave

[marki]

It could be a whole host of things:shrug:. It is pretty rare in my experience for a refractor to need collimation though many have the facilities to do so. I have never had to do it on mine even after changing the focuser for another.

Mark

[dpastern]

Well, I could run ccd inspector on a few other images (moon image comes to mind), although that was taken in the same imaging session as the M42 image above. I have a few other images from different nights though, might give it a bash.

Dave

[dpastern]

Update:

Just for fun, I plugged the battery into power this morning and the damn thing started bloody well charging...what gives!!?!?!?!! Yes, I had the button set to charging. Yes, I had the power adaptor plugged into the wall socket properly, the switch turned on, and the power pin plugged into the battery properly. Yes, I'd tried depressing the fuse switch as well...I have no idea why the sucker is working now, but I'm *happy*.

I'm about to go have a play with the focuser and see what I can manage.

Polar alignment and drift alignment will just be a matter of practice and refinement of technique. I'm still at a lost as to why the focuser won't reach focus at all once the focuser has started to slip.

Thanks once again everyone for help and advice.

Dave

[troypiggo]

Good news. Keep persevering with that focuser! :)

[dpastern]

:D:D:D:eyepop::D:D

Sure aiming to do so!!!

There are a few other hex bolts under the focuser, I'm not sure what they do, and SkyWatcher doesn't seem to provide any information either...pretty poor documentation to be honest.

Dave

[marki]

Be careful with those Dave as they are most likey the screws which set the preload on the bearings. Too tight and you will damage the draw tube.

Mark

[dpastern]

mmm, I did tighten them a fraction, but cautiously. If anything happens, as far as I'm concerned it can be repaired under warranty - no instructions, no warnings on the unit, they can't blame me for their own lack of instructions.

Dave

[TrevorW]

Dave

A are you using your scope at home if yes then

a) buy a long extension cable
b) a power board with switches
c) 12v 5 amp hour regulated power adapter and get rid of the tank

As to the focuser get rid of the standard Skywatcher one buy a William Optics crayford focuser cheaper than the rest and work well

As too focus buy two extensions tubes a 50mm and 100mm as sometimes their isn't enough back focus to bring the scope too focus

PS: IMO don't trust DSSInspector depending on what settings etc you give it such as monochrome or bayer image, what size camera pixel you input, focus length of scope, whether single or multiple images, whether image stacked with a dark, these will all retrurn conflicting results

look at you diffraction rings in and out of focus to and this will give you a guide as to whether the scope needs collimating

Cheers

[dpastern]

Trevor - my deepest apologies, it seems I missed your reply back when I posted this. Thanks for the reply and info, sounds good.

Things are looking better on a few issues.

1) Whilst the focuser is slipping, it does only seem to be when the OTA is basically pointing towards Zenith. It does slip even with the Andrews 2" 80º eyepiece, which is NOT that heavy. Slipping isn't really an issue with the eyepiece when away from Zenith. The camera (Mark IIn) seems mostly OK as well now, at least from my experience over the past 2 outings with the scope setup.

2) My ability not to achieve focus seems to be only when using the WO diagonal. When imaging, I am now removing the diagonal and attaching the camera directly to the focuser. No further issues, focus achieved every time. Much happy am I!

Thought that I'd update everyone :)

Dave