10-Micron GM2000HPS - installed and waiting :-)

[ChrisLX200]

I finally finished installing my 10M GM2000HPS-II U/P but of course now the weather is dreadful (to be expected). So I've done all I can for now and I'm just awaiting a chance for first light. This mount will replace my venerable Losmandy G11 as the main imaging mount but I will keep the G11 as a portable setup - talking of which, whoever suggested the name 'Ultra-Portable' for the GM2000HPS was surely having a laugh because it's quite large and heavy. I'm just glad I got this version and not the monolithic version because at least this one can be split into two main parts.

A bit late for an un-boxing pic?

I needed to make a new pier adapter of course and this was completed in due course. I went to the trouble of making it so that it could be accurately levelled but in fact this is not essential for the mount to work correctly. No matter, it's done now.

I also needed to adapt my home-made weights to fit the larger 40mm diameter counterweight shaft, that meant boring them out but also making some Delrin sleaves so they could be swapped back onto the G11 if required.

Additionally, I wanted to avoid the annoying issue I put up with for years with the G11 - that of the scope/camera threatening to hit the pier when pointing near the zenith. To that end I made a saddle extension which provided an offset of about 3". I just tried it out today to test all-around clearance and it works! No more worrying about the scope hitting the pier :-) It will also carry a small accessory shelf when I get around to making it.

Last couple of pictures, the mount installed on the pier, and the scope and connections all sorted - and a small person shown for scale :-)

I'll follow this up with a report when I've managed to get first light :-)

ChrisH

[triton1]

That's some nice engineering work going on there(ex toolmaker myself).I hope you get clear skies very soon,good luck.

[mcolbert]

like the mount, but the cables - now there lies another thread...(now where's the smiley for perplexed?)

[ChrisLX200]

like the mount, but the cables - now there lies another thread...(now where's the smiley for perplexed?)

Ah yes, forgot about those :-) They are not plugged in as shown, I wrap them around the OTA and lift it all off in one piece for transport and that is how it is in the photos.

ChrisH

[ChrisLX200]

That's some nice engineering work going on there(ex toolmaker myself).I hope you get clear skies very soon,good luck.

Thanks John, these tools have come in quite handy for this job.

ChrisH

[ChrisLX200]

It was a rainy afternoon so I made a small bracket to hold an electronic finder scope (a QHY5L-II + lens) , this comes in handy to see exactly where/what the scope is pointing at. There are quite a few obstructions around the garden (trees, hedges, buildings etc) so using this camera I can immediately see whether a target has cleared one of them. Also quite handy for creating a mask for Per Frejvall's Model Maker for the GM2000HPS. I've tried the camera in daylight to align it and also at night when off the scope so I know it works.

ChrisH

[Zakalwe]

What a lovely looking installation. I do like the electronic viewfinder too...very clever.

:icon_salut:

[perfrej]

You won't need that finder... That is one thing that is for certain!

/p

[ChrisLX200]

You won't need that finder... That is one thing that is for certain!

/p

Oh, it's not for finding stars - it's for seeing the local obstructions!  Wish I had a clear horizon all around then I wouldn't need it :-)

Handy also for watching the FOV so if an aircraft or satellite goes through the field during a long sub I just cancel and start again (I live not far from Manchester airport and a low plane can ruin a sub sometimes). I don't sit there watching intently, just keep an eye out while doing other things on the computer :-)

ChrisH

[ollypenrice]

Ah yes, forgot about those :-) They are not plugged in as shown, I wrap them around the OTA and lift it all off in one piece for transport and that is how it is in the photos.

ChrisH

Awe, I thought you took power from three different power stations just in case! 

They are great mounts, no question whatever.

And I do believe you have the same colour of Hammerite on the pier as we have in the robotic shed here. It's a sign!

Olly

[ChrisLX200]

Well despite very poor conditions I managed to get First Light with the mount tonight :-)  First I had to route my cables so there was no issue during median flips, balance the scope (not too carefully I must confess, I was in a hurry!) then learn how to generate a sky model using Per's Model Maker for the first time. There were a few stumbling blocks along the way but nothing serious. It was only after I finished for the night and took the scope off that I noticed the dovetail bar which is bolted to the scope was loose!  It was never going to fall off or anything but there was certainly enough movement there to mess the model up. Anyway, the model I finally got was not too bad despite that and I tried 3 x 20min unguided Lum subs of M33, I reckon under the circumstances the result is encouraging. With the dovetail bar correctly tightened up to remove flexure (!) and no pesky clouds it will be much improved :-)

ChrisH

[perfrej]

Very nice result! It looks like you will be doing OK with that setup.

/per

[johnrt]

That's some bit of kit, jealous? Me, no! Honest!

[ChrisLX200]

Very nice result! It looks like you will be doing OK with that setup.

/per

It's going to work just fine Per, and a final act of faith - I've now removed the guidescope.  I'm going to miss those 'Lost Guidestar' beeps from PHD2, now how am I going to know it's gone cloudy? :-)

ChrisH

[ChrisLX200]

I managed to generate a decent model tonight after securing the scope so it doesn' t rattle :-)   RMS error of 3.25 arcsec.  Shortly afterwards the clouds roll in so I'm still waiting to test the tracking.

Just for laughs I recorded the view from my electronic finder during the 75-point modelling run :-)

ChrisH

[CCD Imager]

Hi Chris

Congratulations on the new mount and getting up to speed. I am in a similar situation to you having played with Model Maker and getting used to the GM2000. I will be off to Kelling Heath Sar Party next week, so hope to get some concrete imaging done there. I will just take my little TAK FSQ and go to sleep when its imaging

My only issue is that I had imbalance in DEC and so bought a new APM Losmandy plate to move the scope further up the mount. I don't know how much an issue imabalance is, but most 10 micron users say it is a must and there is a section in the manual describiing its importance.

Adrian

[ChrisLX200]

Hi Chris

Congratulations on the new mount and getting up to speed. I am in a similar situation to you having played with Model Maker and getting used to the GM2000. I will be off to Kelling Heath Sar Party next week, so hope to get some concrete imaging done there. I will just take my little TAK FSQ and go to sleep when its imaging

My only issue is that I had imbalance in DEC and so bought a new APM Losmandy plate to move the scope further up the mount. I don't know how much an issue imabalance is, but most 10 micron users say it is a must and there is a section in the manual describiing its importance.

Adrian

Hi Adrian,

Thanks, I did see your comments on the 10-Micron site. I have not used the motor torque method of balancing, just did it by eye (but I'm a good guesser ;-) ). The weather has been abysmal ever since I put the mount on the pier and there's been little chance to experiment further, I certainly hope the weather will be better for you at Kelling!

I also struggled with DEC balance and replaced the dovetail bar for a longer one, my original was home-made for the G11 but it is too short for this saddle. I got the impression from the manual balance was not _that_ critical, in fact it says the mount can cope with a 'reasonable' amount of imbalance but if excessive will cause motor strain. I should think balance would need to be a long way out before that happens. For pointing the scope, the motor(s) will draw as much current as needed to put the scope where the encoders say it should be, only if something is physically loose will imbalance affect accuracy (ask me how I know this...).

I'm still looking at options for an additional OTA that will provide me with more reach for galaxies, PNs, and similar small/faint objects. Has to be light enough to be handled by myself alone - and mounted/dismounted each session. I'm looking at Orion Optics (UK) ODK12 at the moment but am wary of big reflectors like this in case internal bits move when slewing/tracking. That would ruin any chance of operating unguided.

ChrisH

[wolfman_4_ever]

I usually just eyeball balance with my gm3000hps.  I have then done the balance routine in the HC and am usually close enough.  With the premium mounts and encoders, you don't need to imbalance the east side or hand weights off the scope (hehe)

Chris, I currently am running an np127is as well.  I also have a Planewave 14 waiting to be installed but am waiting for the Baader Planewave Saddle to do a much more ridgid side by side setup (more real estate for a hub and rigrunner).  Not sure how the ODK's manufacturing tolerances are.  Maybe a RCOS 12 or PW 12.5?  AG Optical?  CFF Telescopes might be an option.

Make sure you take into account for the image circle in your next scope. If you plane on going to a larger ccd sensor.

[PaulB]

It all looks very impressive Chris,

It's just a shame the missus won't allow an obsy.

And the cloud will insist on spoiling all the fun

That bracket looks interesting to hold your little camera. 

BTW.

Does your daughter know. She's now the un-offical, 10 Micron advertising model 

[CCD Imager]

Hi Chris

In the old days it was good to have a little imbalance as the teeth would mesh better, but not only 10 micron, but many other manufacturers now say that mounts needs to be well balanced. I also haven't tried the balancing technique, perhaps something to play with when it is cloudy at Kelling!

I have the scope you are looking at. I have had the 12 inch ODK for about a year. I will be trying it this Autumn once I have my pier adapter installed, but the optics are fixed and I have a feathertouch focuser on it, so am cautiously optimistic. BTW the scope is perfect for longer FL imaging - I have a FL of 2M with a ratio of F6.8 giving a "good speed" for imaging and give a native flat field. There is very little alternative to longer FL imaging on the market than Optimized Dall Kirkhams that offer a a fastish focal ratio.

Adrian

[ChrisLX200]

Hi Chris

In the old days it was good to have a little imbalance as the teeth would mesh better, but not only 10 micron, but many other manufacturers now say that mounts needs to be well balanced. I also haven't tried the balancing technique, perhaps something to play with when it is cloudy at Kelling!

I have the scope you are looking at. I have had the 12 inch ODK for about a year. I will be trying it this Autumn once I have my pier adapter installed, but the optics are fixed and I have a feathertouch focuser on it, so am cautiously optimistic. BTW the scope is perfect for longer FL imaging - I have a FL of 2M with a ratio of F6.8 giving a "good speed" for imaging and give a native flat field. There is very little alternative to longer FL imaging on the market than Optimized Dall Kirkhams that offer a a fastish focal ratio.

Adrian

Well that's interesting to hear about your ODK12, it will be interesting to see what RMS you can get with the sky model when you eventually get to try it. This OTA does tick all the boxes for me, as you say - focal length, aperture, spot-size looks good (if true!), weight, and the image circle is hopefully just about big enough (16803 sensor is 37mm square, 52mm diagonal and the ODK12 quotes 52mm circle). For a focuser I need something other than a Crayford, the FLI Atlas looks stiff enough but only 8mm of total travel makes it tricky to get initial focus in the first place. I really need a good R&P focuser and will look at other alternatives (did Orion Optics supply the Feathertouch or did you source it yourself?) The most important feature for me though is how the primary is retained in its cell.

ChrisH

[ChrisLX200]

It all looks very impressive Chris,

It's just a shame the missus won't allow an obsy.

And the cloud will insist on spoiling all the fun

That bracket looks interesting to hold your little camera. 

BTW.

Does your daughter know. She's now the un-offical, 10 Micron advertising model 

Well an Obsy would have to be where the pier is - which is a tad inconvenient in the middle of the lawn [unless you feel like digging it up again? :-)]  I sort of expected the 'new kit clouds' but it will all start again when that new camera turns up, so I figure the next clear sky might be around December. Remind me to ask Santa for one.

ChrisH

[CCD Imager]

Which camera have you got? I have the QSI 683, so not full frame. Having a full frame camera brings a whole load of new problems - flat field, bigger filters, all costing a lot more than just a new camera!

I sourced a few things myself for the ODK, Losmandy plates, focuser and also a circular Kendrick secondary dew heater that initially pinched the optics! This is a necessity if you don't have an observatory. The primary rests on the central hub and the baffle tube locks down onto the mirror to secure it in place and gives a solid connection, although there is cork between the baffle tube and mirror that could change with a change in temperature. I too was initially concerned about the mirror potentially sagging, but OO advised that it is not an issue with a 12 inch mirror and I have not had any problems.

This is going a bit off topic, happy to take private if you want to chat more or even move to the telescope section?

Adrian

[ChrisLX200]

Which camera have you got? I have the QSI 683, so not full frame. Having a full frame camera brings a whole load of new problems - flat field, bigger filters, all costing a lot more than just a new camera!

I sourced a few things myself for the ODK, Losmandy plates, focuser and also a circular Kendrick secondary dew heater that initially pinched the optics! This is a necessity if you don't have an observatory. The primary rests on the central hub and the baffle tube locks down onto the mirror to secure it in place and gives a solid connection, although there is cork between the baffle tube and mirror that could change with a change in temperature. I too was initially concerned about the mirror potentially sagging, but OO advised that it is not an issue with a 12 inch mirror and I have not had any problems.

This is going a bit off topic, happy to take private if you want to chat more or even move to the telescope section?

Adrian

It's about what the mount will carry so it can drift a little :-)  I use an Atik490EX with the NP127is, and have a Moravian G4-16000 arriving (when it feels like it). The filterwheel is a 7-pos with 50mm square filters, using Baader for LRGB and Chroma 3nM for narrow band (the latter weren't cheap in 50mm square!). I may have to machine a tilt adapter for the focuser in order to ge it flat but that's no problem, and it looks like the focuser attaches to the backplate and not the mirror carrier/cell. I'm rather curious what the function of the three large cap-head screws are on the back plate - collimation? Support plate?

ChrisH

[CCD Imager]

I have stripped the scope down, so I should know, but without looking (scope packed away atm) it may be due to a circular piece of card that sits just above the mirror and prevents light scatter. I said to Barry, you mean TDE, jokingly!

I needed a plate on the rear of the OTA to take the feathertouch and OO made that for me.

I don't know much about the Moravian CCD camera's, so will be interested to hear how you get on.

Adrian