5 replies to this topic

[TareqPhoto]

Hi,

 

I keep searching a lot for the two scopes to be used in my dual imaging system plan, but i have budget limited and i have the mount capacity limitation too, so i should really start with the mount first than wasting long time already on the two scopes while i might save a lot knowing more about my mount.

 

Anyone here can confirm me about EQ6 mounts ability for carrying 2 scopes of 6" Newtonian for imaging and good enough tracking up to 300-600sec with guiding?

 

This answer will make me relax, if i have to go with smaller scopes then most likely it will only refractors and many people told me only think about triplets, i can't afford two triplets any soon anyway, and if i have to wait longer then i can simply buy another mount less then my EQ6, something like HEQ5 for example and get another 6" Newt and done with it, but before i go for another mount which is also not possible very soon i want to see if i my mount can handle two 6" with accessories including one guide scope/camera and 2 cooled cameras and 2 filter wheels [or even one if i use one cooled OSC camera in future], the tube alone with mounting ring and finder is about 12lb, both are 24lb, if i add two cameras + 2FWs + 2CCs then i don't know what will be the total weight, and i don't know if i better use the side by side option or use the extra saddle came with my mount?

 

Thanks

[johnpd]

I also have an AZ-EQ6. It is a wonderful mount. My understanding is that the AZ-EQ6 can handle 45lbs on each side in dual scope mode. I have seen some posts with scope combinations such as a 6" refractor and a C-8 as dual scopes on the mount. The problem I see is that you would be imaging in Alt-Az mode which would lead to field rotation when imaging. So your sub-frames would be limited. Apparently you can guide using PHD2 but there are some limitations. See this page (https://telescopemou...-great-results/) for details.

 

EDIT: I forgot to add although you can align two scopes in altitude to match the views in each scope (there is an adjustment screw for that), there is no such adjustment screw to align them in azimuth. Unless you have mounting rings that allow you to adjust the scope in azimuth, you may not be able to get exactly the same view in both scope.

 

 

JohnD

Edited by johnpd, 17 September 2020 - 03:15 AM.

[TareqPhoto]

I also have an AZ-EQ6. It is a wonderful mount. My understanding is that the AZ-EQ6 can handle 45lbs on each side in dual scope mode. I have seen some posts with scope combinations such as a 6" refractor and a C-8 as dual scopes on the mount. The problem I see is that you would be imaging in Alt-Az mode which would lead to field rotation when imaging. So your sub-frames would be limited. Apparently you can guide using PHD2 but there are some limitations. See this page (https://telescopemou...-great-results/) for details.

 

EDIT: I forgot to add although you can align two scopes in altitude to match the views in each scope (there is an adjustment screw for that), there is no such adjustment screw to align them in azimuth. Unless you have mounting rings that allow you to adjust the scope in azimuth, you may not be able to get exactly the same view in both scope.

 

 

JohnD

What about side by side on the top of the mount instead?

 

I remember i once slew the mount from PC and it was tracking, not great tracking but it was tracking at least for like 1min or 2 at best, so i can try this also rather than let the mount go to, but i feel this is a risk, or i should buy a pier so it will make things easier, but i still have the idea of side by side anyway, just not sure this is enough for two 6" Newt anyway.

[johnpd]

What about side by side on the top of the mount instead?

 

I remember i once slew the mount from PC and it was tracking, not great tracking but it was tracking at least for like 1min or 2 at best, so i can try this also rather than let the mount go to, but i feel this is a risk, or i should buy a pier so it will make things easier, but i still have the idea of side by side anyway, just not sure this is enough for two 6" Newt anyway.

[I don't know if you saw the additional qualification regarding aligning the two scopes I made probably after you responded.]

 

Mounting scopes in tandem (on a tandem bar) can be tricky to balance.

 

Can I ask why you want to have two identical scopes mounted for imaging purposes? I can see maybe one scope would be smaller to get a larger field of view or having cameras of different resolutions would be some possibilities.

The pier would give you more stability, but still the main issue in Alt-Az mode is field rotation. There is no way around that unless you have derotators on the cameras.

 

How much imaging have you done with a single scope? You may be biting off more than you can chew.

 

JohnD

[TareqPhoto]

[I don't know if you saw the additional qualification regarding aligning the two scopes I made probably after you responded.]

 

Mounting scopes in tandem (on a tandem bar) can be tricky to balance.

 

Can I ask why you want to have two identical scopes mounted for imaging purposes? I can see maybe one scope would be smaller to get a larger field of view or having cameras of different resolutions would be some possibilities.

The pier would give you more stability, but still the main issue in Alt-Az mode is field rotation. There is no way around that unless you have derotators on the cameras.

 

How much imaging have you done with a single scope? You may be biting off more than you can chew.

 

JohnD

Sounds you are still in that Alt-Az method then.

 

So no one did dual imaging system or three scopes for DSO imaging? I can link some who did it, but i don't like to link about others because i always get that kind of response "Ask them, question them,....", so it sounds if someone doesn't know how to do or what to suggest then they assume different methods that doesn't work or not what we look for.

 

Thank you very much.

[TareqPhoto]

I did use single scope or setup for almost 3 years, in all and each and every night it was really   NIGHTMARE and headache, even when i tried my Canon lens F2 at F2 i got data in 2-3 nights, i hate it, i don't like to take one filter per night or almost full night, and when i tried all filters in one night i never get any good results, so the only way i can go with it is to have two different filters in one night together, and each has enough time alone, for example i won't do 3 hours total for 3 separate filters and each taking 1 hour only, mainly for NB, so i want to have 3 hours for one filter and 3 hours for another filter so that yields me 6 hours per night rather than 6 hours in 2-3 nights.

 

I will keep trying until it is done, i was talking with one man yesterday from USA, he simply told me "Tareq, i did it, and you can do it, it is simple, don't listen to others who doesn't know or don't like to have efforts to do it", so in those 3 years i got the answer of that i must use 2 or more setup and not single at all, with single i may image for 1 or 2 more years for not much targets and give up after that no doubt, and if you telling me that a dual system will be even more problematic, i have to do that then i can judge, i already have problems with one setup, i don't mind another problem at least getting something more at least.