Collapsible Dob Tube on a EQ6 mount

icytailmark (Mark) · #1 22-12-2009, 06:09 PM

Would it be possible to put my 12" Skywatcher Collapsible Tube on a EQ Mount?

AlexN · #2 22-12-2009, 06:20 PM

Would it be possible, probably yes... Would you be able to easily balance it? maybe not... Would the truss setup on the scope hold the whole thing square when its tilted and rotated around on its axis? I dunno..

You would need a rather large mount to hold it... a set of custom made rings and a long dovetail that would allow a lot of movement for balance...

mswhin63 (Malcolm) · #3 22-12-2009, 09:31 PM

It has already been investigated by someone, They told me to find the centre of balance of the tube and that will be the point of fixture. On a collapsable DOB that is very low near the mirror.

For observing that would make the eyepiece very high up on the mount although I thought about that and the tripod could be lowered to compensate.

Plausable but not sure if it will be worth it. Am considering it myself.

icytailmark (Mark) · #4 22-12-2009, 09:52 PM

i was gunna start doing some astrophotography next year and was just wondering if i could buy a EQ6 pro mount and put my 12" collapisble tube onto the mount. Would it be hard to do?

mswhin63 (Malcolm) · #5 23-12-2009, 01:15 AM

I believe you would need to machine a bracket, although not sure, clamps to fit around the lower part of the tube would be the critical factor. I am really concentrating on Bartel and EK if possible to provide better views and imagery than trying to go for EQ mounting.

astronut (John) · #6 23-12-2009, 08:39 AM

Mark,
Here's an image of a 10" Lightbridge on a EQ mount.

mswhin63 (Malcolm) · #7 23-12-2009, 09:59 AM

Quote:

Originally Posted by astronut

Mark,
Here's an image of a 10" Lightbridge on a EQ mount.

Cool Bananas

nice rig. Noticed your tripod is lower, did you use standard mounting or are they modified.

astronut (John) · #8 23-12-2009, 10:12 AM

Malcolm,
This is not my rig, so I can't give you any specs, sorry.

ang (Angelo) · #9 23-12-2009, 01:06 PM

Mark,
I recently bought a Skywatcher 12" collapsible as my first scope. I've found these pics and info on mounting it to a EQ6.. something i might try in the future when I get the funds.
Ang

http://www.astronomyforum.net/skywat...be-auto-2.html

AlexN · #10 23-12-2009, 05:30 PM

If you're hoping to do deep sky imaging, I think once you add cameras, guiding gear, and all the other bits and bobs required for deep sky imaging, you'd need something like a Losmandy G11 as a minimum... Even then, in a breeze you might get a case of the wobbles... An EQ6 Pro would probably hold the weight, but I would be skeptical of its performance with that much load and the long moment arm of a 12" F/5 newtonian... be it tube or truss setup..

I hate to sound like a kill joy, but thats pretty much the facts.. I loaded an EQ6 with an 11" SCT + guider/cameras/extras etc and found it VERY difficult to get a decent image out of it... I dropped back to an 8" RC telescope and the results started pouring in.. Its all about weight...

If you were hoping to do planetary imaging - forget everything I said above... It'll be right as rain... just make sure its balanced well..

mswhin63 (Malcolm) · #11 23-12-2009, 11:45 PM

My intention is to get items a bit at a time, I like the idea of a challenge and would equipment the DOB on the mount and look at the issues. Later when the budget tends to itself then upgrade the OTA.

Get the mount first if you want and try it out, nothing to loose really other than having to purchace an OTA later. At least it will be a heavy duty mount and be able to handle anything the future brings out.

Visionoz (Bill) · #12 24-12-2009, 02:48 AM

Quote:

Originally Posted by icytailmark

Would it be possible to put my 12" Skywatcher Collapsible Tube on a EQ Mount?

Hi Mark

See this link here: http://www.myastroshop.com.au/produc...sp?id=MAS-040J

Skywatcher already makes an 12" with the NEQ6Pro Goto mount ready for it with the correctly styled beefier saddle and 12" OTA rings and it looks like the better deal to go with if you have not yet got the collapsible 12" SW

I own a 12" Collapsible SW myself but I had to buy a Losmandy G11 mount as well which can handle the weight of that 21kgs of whole OTA - I am in the process of producing curved blocks to mount a beefed-up D-saddle for it - I tried to get the 12" SW rings originally but was told they would cost more than $300 for the pair !

The posted link to Andy Booth's mod for the EQ6+12" collapsible is where you can get some idea as to where the balance point is but if you want to then do astro-imaging you must consider a way for the balance point to move further forward (well past the top edge of the bottom tube!!) which will be creating more dramas for the mechanical stability of the whole set-up - Andy himself stated that as it stands with just the way he's done it that is very unstable in the presence of wind/breeze - from that it can be inferred that the set-up with the normal EQ6 is very marginal at best

Cheers
Bill

telecasterguru (Frank) · #13 24-12-2009, 11:06 PM

What sort of mount will I need to get a 16" f4.5 truss dob up and running? I am sure it would be cheaper than a 16" SCT.

Frank

stephenb (Stephen) · #14 27-12-2009, 08:07 AM

Sounds like you've set yourself a big challenge there, Mark. My main concern would be the height of the eyepiece once the lower tube assembly is mounted in rings.

The good ol' Skywatcher 12" on an EQ6 looks impressive. I nearly bought one a few weeks ago.

Quote:

Originally Posted by telecasterguru

What sort of mount will I need to get a 16" f4.5 truss dob up and running? I am sure it would be cheaper than a 16" SCT.

Frank

Frank, I have been thinking about this also.

mental4astro (Alexander) · #15 27-12-2009, 08:44 AM

I guess anything is possible to stick anything to anything else, so long as the superglue holds...

I would suggest a couple of things to keep in mind.

* the truss system of the SkyWatcher is a three pole set-up. This design does not have the structural strength of the Light-Bridge to deal with the 'crush' of mounting rings. 'Triangles' are needed here.

* If you have this set-up any where but an observatory, the sail effect of the OTA with be more heightened by its light-weight materials. The materials the dob is made from is not designed for this mounting system. You are asking this OTA to perform in a way it is not designed for.

You may need to do some 'surgery' to get such a large OTA up to scratch for this type of work if you want more than just planetary photography.

Meade had a range of f/5 newts on eq. mounts some thirty to twenty years ago. The mounts where massive, stumpy things, some designed for their giant 16" f/4.5 newt. May be worth stratching up a few images to get some ideas. One thing with these is that the centre of gravity is higher as they are solid tubes.

telecasterguru (Frank) · #16 27-12-2009, 08:49 AM

Hey Stephen,

Where can I get that scope?

Frank

mswhin63 (Malcolm) · #17 27-12-2009, 06:03 PM

I am considering fork mount for the 12" collapsable, main reason is the DOB mounts seemed to be perfectly positioned already and balanced.

I am looking at the option now, hard to find ATM fork plans.

bmitchell82 (Brendan) · #18 27-12-2009, 06:13 PM

I run a 10" dob on a eq6 and let me tell you straight away even though a eq6 will hold it and you "CAN" get decent images out of it its a very very big mission and 9 times out of 10 you will be dissapointed with what you capture for astro photography.

i have tuned the guts out of my eq6 fabricated 25mm thick saddle plates reinforced the hell out of my rings pretty much i have made everthing capable of holding way more than they are and where the EQ6 falls down is it phiscally cannot hold the weight from swinging around my mount has no decernable back lash, yet if i tap the counter weight the ota wobbles, thats just from a small tap. Presently im running a ed 80 with a modified finder -->guider and in heavy wind i still have round stars i get great results all the time.

If you have a dead still night and your seeing is great then the eq6 can point the ota and make sure it stays on target, if you have a really light breeze thats constant the eq6 can give you a 50-75% return for good images, anything much more than about 5km/h breeze game over.

i think the saying goes, "you can only squeeze a lemon for juice so much..."

If your keen to run such large scopes for imaging have you looked at the servo cat/argo navis with a field de rotator? i havn't done any research but thats your tracking/pointing ability and you can run some serious kit with those things that can be adapted to biger/alternitive ota's

icytailmark (Mark) · #19 27-12-2009, 11:39 PM

I think i will sell my Collapsible DOB and buy this

http://www.myastroshop.com.au/produc...sp?id=MAS-040J

I really wanna get into astrophotograhy and you cant really do astrophotography on a DOB.

What camera do you use Brendan? I want to start off with taking picture of planets then as i get more experience do deep sky stuff.

bmitchell82 (Brendan) · #20 28-12-2009, 01:07 AM

well you have 2 options. you can either spend your money and then spend alot more money, or do it right straight up and produce results your happy with.

1st thing, astrophotography is hard work sometimes.

2nd thing, everybody tells you to start off with starter gear. ive always done this treck and ended up spending about triple what i should have.

get a cooled dedicated astro ccd, this will save you no end of headaches why? NOISE... dslr's are great for putting on and getting going but you soon find the limit of the dslr as for me it took me about 4 months to reach this limit but im stuck with what i have for now.

qhy8 is a great starter or a atik 4000 there are others too ask your questions do your research most importantly have a look at other peoples gear.!

as for a telescope, if you want to use a 12" newt on a gem, FORGET THE EQ6 for reasons mentioned before. they just cant handle it and i know that the neq6-w is no different to a eq6pro that i use, they hvae a few other bits, but nothing different where it needs to be.

get a losmandy g11, or astrophysics equivelent, and a nice little scope, wide field is best for starters, you could even start with a little ED 80 skywatcher, they can be had for nix, a good ccd and mount will make the ed proform really well, then you can figure out where you want to go. aka what you like to image

i love to image nebula, so i use a mixture of the 10" newt and the ed 80.

to do it right, you will be looking at about 8 - 10 grand, shudder if you will at that but its not something that depriciates or will cost you more to keep operational.

to do it semi right you could get away with it for about 4-5 grand.

and to do it the wrong way will cost initially 2-3k, but then triple or quadriple it and add in the time andd headache

pm me if you would like some more help.