150p eq3-2 non guided AP Expectations

[Peco4321]

Had my lovely Skywatcher 150p on eq3-2 for a few months and absolutely hooked on this new hobby. I have also got loads of planetary pictures and lunar shots using my canon 1100d at prime focus and eyepiece projection methods of AP. 

I have now started to try DSO pictures at prime focus but limited to only a few seconds exposure due to not having any motors for tracking. Last night got my first pictures of Andromeda Galaxy and though I am chuffed, they are nothing special, as focus is not great.

Do I need to accept that this scope is never going to give great AP results for DSO's even with tracking, due to not really reaching focus very well, or should I get the motors and just give it a go?

I was heartened by some prime focus shots of Polaris, I could get a lot longer exposures due to less noticeable movement, so that gave me a sense that tracking would be the next step. 

Thoughts please if I am just expecting far too much from the 150p-ds's little brother (or sister!)

 

 

[nightfisher]

An RA drive motor would make a difference but if your going to get into deep sky AP you will need a better mount, i have the larger EQ5 with dual dc drive and i can get over a minute unguided on a good night

[Peco4321]

55 minutes ago, nightfisher said:

An RA drive motor would make a difference but if your going to get into deep sky AP you will need a better mount, i have the larger EQ5 with dual dc drive and i can get over a minute unguided on a good night

Think I'll have to stick with eq3-2 as need other things first like RACI finder scope and just make do. So with motors I could maybe expect up to 1 minute subs in good conditions?  My main concern is getting a better focus and if that is expecting too much. 

[ronin]

The 150P is I think 1200mm focal length so you are not going to get a long exposure of any sort untracked. There used to be a sort of "guide" as in 600/Scope focal length = exposure in seconds for untracked, but that always seemed a relatively short result, so not sure what it was.

Guess you have 3 problems, no idea why I am laughing as I write this:

Scope is really too big, both weight ahd physical size.

Mount is a bit too lightweight, EQ5 would be better.

No drive on the mount.

Reason for "laughing" comment was i realised I was about to say mount and scope are both problems and really that leaves nothing else. DSLR is hopefully OK.

However you have what you have and are not asking about upgrades. You will need the dual axis drive for immediate improvement, if the EQ3-2 does not have a polar scope then you will want one of those. Get used to getting the polar alignment as good as possible, take your time but get it as good as reasonably possible. Find out inexpensive options to get the mount as stable as reasonable. Extra weigh or pads seem the common items.

Check the balance of the scope, with DSLR on, you may be able to improve matters a little via this.

With tracking and good polar alignment I would expect you to get 30 seconds and maybe up to 60 seconds (questionable). I assume you have an intervalometer/remote time thingy. So if you get motors (£100 area) you could try say a 45 second exposure, a 15 second wait and say 15 exposures. That will occupy 15 minutes of your life and give you a set of exposures to play with. Pick say 4 different targets and repeat. Targets say: Pleiades, Casseiopia, Cygnus, M13. Then it is off to play with DSS. I think DSS will handle jpeg files now (?) so maybe keept it simple and try that option at first. Maybe 18 exposures, that way if 1 in 3 fail you have 12 exposures to stack.

Owing to the scope size avoid wind or breeze as much as possible, this would make the scope move and so you lose images. The physical size and focal length both contribute to this.

One aspect of getting tracking on the EQ3-2 is that you can remove the scope and attach a DSLR all on it's own and get some nice widefiled shots - Cygnus and Casseiopia for the milky way behind them.

After that it really is better equipment, a "small" set up would be EQ5 and a 72mm refractor, or the 130PDS, and the 130 would be better on the HEQ5. Will say t eh HEQ5 is good, solid and far too heavy to be a mount to grab and head out into the night to get a few images with. The EQ5 is better suited to grabbing images at short notice, just you lose stability a bit. But an EQ5 being used is better then an HEQ5 not being used.

[Peco4321]

10 minutes ago, ronin said:

The 150P is I think 1200mm focal length so you are not going to get a long exposure of any sort untracked. There used to be a sort of "guide" as in 600/Scope focal length = exposure in seconds for untracked, but that always seemed a relatively short result, so not sure what it was.

Guess you have 3 problems, no idea why I am laughing as I write this:

Scope is really too big, both weight ahd physical size.

Mount is a bit too lightweight, EQ5 would be better.

No drive on the mount.

Reason for "laughing" comment was i realised I was about to say mount and scope are both problems and really that leaves nothing else. DSLR is hopefully OK.

However you have what you have and are not asking about upgrades. You will need the dual axis drive for immediate improvement, if the EQ3-2 does not have a polar scope then you will want one of those. Get used to getting the polar alignment as good as possible, take your time but get it as good as reasonably possible. Find out inexpensive options to get the mount as stable as reasonable. Extra weigh or pads seem the common items.

Check the balance of the scope, with DSLR on, you may be able to improve matters a little via this.

With tracking and good polar alignment I would expect you to get 30 seconds and maybe up to 60 seconds (questionable). I assume you have an intervalometer/remote time thingy. So if you get motors (£100 area) you could try say a 45 second exposure, a 15 second wait and say 15 exposures. That will occupy 15 minutes of your life and give you a set of exposures to play with. Pick say 4 different targets and repeat. Targets say: Pleiades, Casseiopia, Cygnus, M13. Then it is off to play with DSS. I think DSS will handle jpeg files now (?) so maybe keept it simple and try that option at first. Maybe 18 exposures, that way if 1 in 3 fail you have 12 exposures to stack.

Owing to the scope size avoid wind or breeze as much as possible, this would make the scope move and so you lose images. The physical size and focal length both contribute to this.

One aspect of getting tracking on the EQ3-2 is that you can remove the scope and attach a DSLR all on it's own and get some nice widefiled shots - Cygnus and Casseiopia for the milky way behind them.

After that it really is better equipment, a "small" set up would be EQ5 and a 72mm refractor, or the 130PDS, and the 130 would be better on the HEQ5. Will say t eh HEQ5 is good, solid and far too heavy to be a mount to grab and head out into the night to get a few images with. The EQ5 is better suited to grabbing images at short notice, just you lose stability a bit. But an EQ5 being used is better then an HEQ5 not being used.

Great reply and advice, thanks. Loads to mull over. Cheers. 

[SilverAstro]

I dont know the Eq3-2, could you add a tangent arm and turn it into a "Barn Door" drive ? Prob. not good enough for prime focus at the scope but you could then mount your DSLR piggyback with its camera lens, you could even use the scope for visual/guide/corrections

[Peco4321]

1 hour ago, SilverAstro said:

I dont know the Eq3-2, could you add a tangent arm and turn it into a "Barn Door" drive ? Prob. not good enough for prime focus at the scope but you could then mount your DSLR piggyback with its camera lens, you could even use the scope for visual/guide/corrections

I can screw my camera onto the tube ring to piggy back, so that will be useful when I eventually get some motors for it. This is all great advise from everyone. 

[wimvb]

I do have the EQ3 (Pro) with synscan and a 150P (750 mm focal length)

You can image bright DSOs with this set up, but don't expect too much. The scope with camera is too heavy for this mount, but if you get tracking to work, and can limit backlash, you can get some decent results (on bright objects).

For focus you will need a Bahtinov mask.

An alternative to using the scope, is to put your camera with lens directly onto the mount (no piggy back, that won't solve the weight issue). Here's some examples of what can be done with this configuration

 

In the mean time, save up for a sturdier mount.

Good luck

[Peco4321]

41 minutes ago, wimvb said:

I do have the EQ3 (Pro) with synscan and a 150P (750 mm focal length)

You can image bright DSOs with this set up, but don't expect too much. The scope with camera is too heavy for this mount, but if you get tracking to work, and can limit backlash, you can get some decent results (on bright objects).

For focus you will need a Bahtinov mask.

An alternative to using the scope, is to put your camera with lens directly onto the mount (no piggy back, that won't solve the weight issue). Here's some examples of what can be done with this configuration

 

In the mean time, save up for a sturdier mount.

Good luck

Thanks for those cracking examples of what one day I might get half way near to.   

[wimvb]

If you need/want to "beef up" the tripod (it's very susceptible to vibrations), here's an article on how it can be done. Haven't tried it myself, but now that I have a better mount (se my signature), I may have a go at it.

http://www.cloudynights.com/page/articles/cat/articles/beefing-up-hollow-aluminum-tripod-legs-r3016