Skywatcher Startravel 102 SynScan AZ GOTO

[MeSeany]

Will this set up be able to take deep space pics in the following format - 12 to 15 subs at ISO 1600, exposed at 15 or 20 seconds, stacked in Deep Sky Stacker.

I presume I could add a canon 1100D on the eyepiece and let it track?

Here is the article - some great pics

http://www.astrophotography-tonight.com/astrophotography-on-budget/

[Cornelius Varley]

Don't use an eyepiece. Just connect the camera body directly to the focuser using a t ring and take more subs.

[Ant]

I currently use an ST102, but there are a couple of draw backs.

1. The CA on these scopes isn't great, so you get blue halos around the brighter stars using a colour camera.

2. You say that it's a ALTAZ goto, 15-20 second subs should be fine. There will be field rotation between subs but the stacking software will help fix that.

3. I do not know how accurate the tracking will be on the mount.

ISO1600 is way too high at this time of year. I would suggest ISO 400 while it's still warm. Then ISO800 in the winter.

Cheers

Ant

[Alien 13]

The key to AP on a budget is to keep the FL as low as possible fast camera lenses can work with subs of 20sec to 1 mins but scopes normally require a quite a bit more going for higher FL will mean a much larger mount.

Alan

[ronin]

I would have said the 102 was getting heavy for the Alt/Az and if you added a DSLR then cetainly heavy.

Length is also a problem as you will have to possibly limit the angle that it will go to - I think there is a Max Alt setting somewhere.

The 102 will give a measure of CA and there will also be SA present.

As you say the exposures will need to be limited in length, and the more you take the more time passes and so more rotation of the object occurs. I do not know if there is a maximum rotation before something like DSS says no more. Time adds up as you will need to allow the camera sensor to cool between exposures.

Not sure how accurate what the person says is true: Myth#1 is certainly odd, take DSLR 300mm lens and point at moon with centre spot metering and you get an image of the moon. No scope required just an exposure of 1/100 to 1/250 second. So most of his summary of what is required is wrong. No scope required sort of throws that all out.

Myth#2 - Well you can get away with short length exposures if you can get enough of them before rotation stuffs it all. BUT an equitorial make it a hell of a lot easier and ultimately you get  better results quicker.

Myth#3 - You do get what you pay for, I see the image of the Horsehead Nebula uses a $2000 Sbig ccd for it and the exposure length is not possible on an Alt/Az - 5 minutes each, meaning is has to be an Eq and guided as well. So I would question this. So someone to get that image has paid to get that and what they paid for is not what the author seems to say is all you need.

[bogdog]

be VERY carefull of this mount when you add your camera to it!!

it heads south very very fast and hits the legs ,if not tightened enough the camera is bouncing around the ground

it has a very small dovetail fixed to tube ,so not much wiggle room balancing scope/camera

the gearing (on mine) seems non existent,ie:no resistance to any weight,it will just plummet southwards

when you do get it balanced it is okay,but be wary when moving scope higher in the sky as it will get to a point where

the gears wont hold it and it drops again

[Lee_P]

What bogdog said. I used an ST102 / DSLR with an AZ mount but it was all rather frustrating. Then I upgraded to an EQ3 GOTO and the fun began!

[MeSeany]

What about the similar 

Skywatcher Skymax 102 SynScan AZ GOTO

http://www.firstlightoptics.com/az-goto/skywatcher-skymax-102-synscan-az-goto.html

[MeSeany]

The guy on the site uses the 80mm Rokinon short tube on my Meade Alt-Az mount

So I was hoping that that either the 

Skywatcher Startravel 102 SynScan AZ GOTO

or

Skywatcher Skymax 102 SynScan AZ GOTO

[oldpink]

at over 12 FL its not ideal for AP esp for short exposures

[MeSeany]

What bogdog said. I used an ST102 / DSLR with an AZ mount but it was all rather frustrating. Then I upgraded to an EQ3 GOTO and the fun began!

So the EQ3 goto fixed things for deep space photos?

[Lee_P]

Yep, deep space is certainly achievable. I've been using an ST102, EQ3 PRO Synscan GOTO, and Nikon D700 camera. Only been imaging for a few months, but am beginning to get half-decent results, from near a city centre too. Some examples are here: 

[MeSeany]

Yep, deep space is certainly achievable. I've been using an ST102, EQ3 PRO Synscan GOTO, and Nikon D700 camera. Only been imaging for a few months, but am beginning to get half-decent results, from near a city centre too. Some examples are here: 

Very nice - low magnification?

[Lee_P]

Most of those photos were taken with the camera body directly attached to the telescope, basically making the telescope a gigantic telephoto lens. So low magnification but wide field of view. That's what short-tube refractors like the ST102 are best at. I'm not sure what the magnification for that set-up would actually be... maybe wiser minds can educate us both. The pics are generally cropped in quite a lot and have plenty of editing done, of course!

I think you'll have much more fun with astrophotography if you go for the EQ3 PRO mount. £385 from First Light Optics (http://www.firstlightoptics.com/skywatcher-mounts/skywatcher-eq3-pro-synscan-goto.html)

[MeSeany]

Has anyone come across the 

Celestron Nexstar 102 SLT 

How does this compare to the Sky watcher 102?

[oldpink]

you need to settle down and think out your decision and exactly what you want to do
if its DSO you want to look for a short focal length scope Esp for shorter unguided exposures

then read up on the site to see what will suit you best for your budget (which will never be enough)
and look at other peoples results with similar equipment

[ollypenrice]

There is no such thing as magnification in AP. An 8x binocular makes the image on your retina 8x bigger. But what is the starting point for image size in AP? There isn't one so it can't be magnified! We talk instead about image or plate scale.

This all sounds a bit lashed up to me. These short tube refractors are a pretty perfect manifestation of everything you should try to avoid in choosing optics for AP. They have massive CA so give blue bloated stars, they have severe field curvature and droopy focusers. Surely a cheap small Newt would be faster and far better on all counts? The fast achromats are cheap and nasty. (I have two for guiding).  The small Newts are cheap and not nasty... And why start with the wrong mount? You do AP on an equatorial. That's what you do. They come up second hand.

Olly

[MeSeany]

you need to settle down and think out your decision and exactly what you want to do

if its DSO you want to look for a short focal length scope Esp for shorter unguided exposures

then read up on the site to see what will suit you best for your budget (which will never be enough)

and look at other peoples results with similar equipment

Id like to spend around £400 on a beginners deep space photos scope - like this chap 80mm Rokinon short tube on my Meade Alt-Az mount, 12 to 15 subs at ISO 1600, exposed at 15 or 20 seconds, stacked in Deep Sky Stacker

http://www.astrophotography-tonight.com/astrophotography-on-budget/.

[MeSeany]

There is no such thing as magnification in AP. An 8x binocular makes the image on your retina 8x bigger. But what is the starting point for image size in AP? There isn't one so it can't be magnified! We talk instead about image or plate scale.

This all sounds a bit lashed up to me. These short tube refractors are a pretty perfect manifestation of everything you should try to avoid in choosing optics for AP. They have massive CA so give blue bloated stars, they have severe field curvature and droopy focusers. Surely a cheap small Newt would be faster and far better on all counts? The fast achromats are cheap and nasty. (I have two for guiding).  The small Newts are cheap and not nasty... And why start with the wrong mount? You do AP on an equatorial. That's what you do. They come up second hand.

Olly

Sounds like good advice - I think the 

Skywatcher Explorer 150P-DS EQ-5 PRO GOTO is a good set up - but Im guessing that the HEQ5 would be the min re AP?

[oldpink]

I was running up to 3 minutes with an EQ5 unguided and could have pushed it further but wind was an issue with my 200p and I was overloading the max as well
the 150 is also a decent scope and more suited to AP then some others you mentioned

but you won't get the 150 and the EQ5 goto with a budget of £400 even second hand that would be a struggle new its £750 plus you need Trings and a few other odds & ends
so min for that rig is about £800

[Atreta]

Can i disagree a bit?

i think you can take pictures with altaz mounts.

There is a brazilian astrophotographer that takes amazing pictures with a celestron 130 slt.

here's a horse head nebula he took:

[Alien 13]

The one key factor with AP is repeatability you have to capture a large number of subs without star trails well aligned to each other ALT-AZ mounts introduce field rotation over a relitively short space of time so it becomes a much more difficult task but not impossible.

EQ mounts makes the process much easier which is what we all want, the accuracy of a particular mount is primarily governed by the focal length of the scope/camera lens used so while something like an EQ3 will happily track a 50mm lens for many minutes it would struggle with subs of 20 seconds with a small newtonion but thats fine if you use it in its comfort zone.

Longer focal length scopes require more accurate heavier more expensive mounts so its important to look at images on forums etc to see where you want to go but putting a large scope on an insufficient mount will only induce a painful experience.

Alan

[ollypenrice]

Can i disagree a bit?

i think you can take pictures with altaz mounts.

There is a brazilian astrophotographer that takes amazing pictures with a celestron 130 slt.

here's a horse head nebula he took:

In all honesty this is not an amazing picture. It has all the faults you'd expect to see from an image taken with this kit. It is a creditable effort, very creditable, for someone using entirely the wrong tools for the job.

My question remains, why use the wrong tools?  In no time at all you will be wanting to re-spend your £400 on the right ones.

Go for little 130PDS Newt, not the 8 inch. (Check out the pictures taken by Uranium235 with his. These are not 'creditable for the scope in use,' they are very simply among the best images being posted on SGL.)

This little scope will be perfect on an HEQ5 but it will still wipe the floor with any alt az system if you put it on a half way decent GEM. If budget dictates a second hand EQ3 then go for that. Go for the best you can. but a coma-riddled, CA monster of a fast achro on an Alt Az mount, no, no and thrice no. At the moment all three of our image scopes are refractors but they are expensive refractors (seriously expensive) and on a budget reflectors are the way to go.

Olly

http://ollypenrice.smugmug.com/Other/Best-of-Les-Granges/22435624_WLMPTM#!i=2266922474&k=Sc3kgzc

[MeSeany]

I was running up to 3 minutes with an EQ5 unguided and could have pushed it further but wind was an issue with my 200p and I was overloading the max as well

the 150 is also a decent scope and more suited to AP then some others you mentioned

but you won't get the 150 and the EQ5 goto with a budget of £400 even second hand that would be a struggle new its £750 plus you need Trings and a few other odds & ends

so min for that rig is about £800

I was watching a chap called Ken over in the US on you tube last night - had 6 rigs set up on the border with Mexico - great blue skys never any clouds...

They had rigs from 14" CST Celestrons, 1x 200p all on great mounts - they also had a small refractor plus guide scope on a small mount

I think for my budget Id be looking at a small refractor - plus mount with the ability to later auto guide using a piece that slots into the eye piece at an angle.

Any ideas what this rig would consist of - the sky watcher 102 + EQ3?

Also - Ken had an eyepiece rigged up the his laptop - you could see saturn on his laptop wow!!!  Was this a guide camera?

[bogdog]

as olly has pointed out....In no time at all you will be wanting to re-spend your £400 on the right ones.

its better to listen to good advice,rather than cut corners now,its an expensive enough hobby doing AP

without wasting your hard earned on something that you will struggle with to start off

even buying what is suggested,after a few months you will want bigger and better

its a never ending money pit you need