astrophotography DSO Imaging help from a novice!

[Graham F]

Hi to all you members on SGL.

I am a novice with 3 months experience with a SW200P dob, having started initially with a pair of Oregon 15 x 70 Bins on a tripod mount.

I have referenced some good books and spent some time with Stellarium and I am encouraged by my new learnt ability to navigate the night sky with the 200p.

I have connected my Nikon D600 (24mp full frame) DSLR to the scope and produced some satisfying photos of the moon, however I am interested in imaging some DSO's. ( I have caught the bug with no cure in sight!)

I intend to get a tracking mount such as a SW HEQ5 Pro Synscan, but for now would like to purchase a wide field refractor and produce some wide field imaging with a basic mount, I understand that subs of around 30 sec can be produced with mediocre results initially until I get a better mount. Also it would be nice to have a grab and go scope which is more convenient than the big DOB.

Also this would give me some images to experiment with the software such as DSS and Registax 6.

So, I have been researching three achromatic telescopes, The Skywatcher ST80 and ST102 (both come with kit mounts ranging from AZ3 to EQ1 and the Bresser Messier AR-102/600 (which looks stylish and has the Hex focus)

However, despite spending somewhere in the region of 4-5 hours so far researching for reviews on the BM102, nothing has been forthcoming>?

I am aware of the issues of CA with these small tube Achromats, however the plan is to Purchase one of the three now, save for the HEQ5 mount, then at a later stage use the scope purchased now as a guide scope and but a better APO doublet or triplet scope for the main tube.

So, having laid the table so to speak, which of the three would you advice and why please, I have been told by two companies stocking the BM102/600 that mechanically it is far superior to the two Skywatchers, but I am concerned that I cannot find ANY reviews on this OTA for its optical quality ?. I am aware that Synta make a few of these 80 and 100mm scopes for different suppliers but I am let to believe that the BM is a separate manufacturer.

Any advice or better still hearing from someone who owns the Bresser Messier AR-102/600 would be amazing, so thank you for reading this long post and thank you in advance of your reply.

Regards

Graham

 

Side note:-

I have a VERY heavy duty pan tilt Manfrotto tripod which I previously used to support my Sinar 5x4 Large format bellows camera so its very steady and has a pan tilt head already fitted, I intend to mount the new scope on this as an AZ to begin with.
 

[Dave S]

Hi Graham

Yep. finding info on the Bresser is a bit of needle in a haystack.  I was able to locate one small comment which indicated that the optics leave a bit to be desired.

https://www.eastmidlandsstargazers.org.uk/topic/8142-refractor-as-an-all-round-grab-and-go/

As always unless you spend cash on an APO doublet or Triplet then whichever refractor you go for is going to have it's limitations.

I've been keeping my eye on the skywatcher ST80 with the idea of getting some refractor practice until I'm in a better position to invest.  I don't mind having to work hard with less capable kit as I enjoy the challenge. And at £100 for the OTA it's not a bank breaker.

Hope the hunt goes well.

Dave...

[carastro]

The HEQ5 is a good choice for imaging.  If you want to purchase a wide field telescope for imaging - rather than go for an Acromat, why don't you buy the excellent WO61 that FLO is current selling, it is suitable for widefield Astro imaging, not expensive and one you won't need to relegate to a guiding scope later on.  

Carole 

[Dave S]

Yes.  I've also got my eye on the Zenithstar.  It looks like a real stunner and is not expensive as things go.  I love the small profile and lightness which is how most of my kit is.  I can see my soon to be aquired Hypercam 183C and the Zenithstar becoming good friends.

Dave...

[pete_l]

1 hour ago, Graham F said:

 the plan is to Purchase one of the three now, save for the HEQ5 mount, then at a later stage use the scope purchased now as a guide scope and but a better APO doublet or triplet scope for the main tube.

The good news is that you already have an eminently capable telescope - your DSLR!

So far as buying a small refractor goes, for £150 more that what you are considering you can get yourself an iOptron Cube pro and mount your camera on that. It has GOTO built in and it also has the ability to add a guider and therefore take long exposure images, too. You can either build yourself a wooden wedge or use it on a Sky Adventurer wedge as some people (not me) already do. The tripod that comes with the iOptron is widely considered to be junk. But your Manfrotto would be a very capable replacement.

But as a starter, a decent DSLR like the one you already have with 100-200mm of focal length will produce some great images. The exposure time could well be limited, at that focal length / field of view, by your local skyglow (pollution) rather than the limitations of the mount.

[happy-kat]

Given you have a full frame camera how many lens do you already own, use those instead of a achromatic.

[Dave S]

Totally agree. Most of my imaging is done at 200mm. I'm going to go for the zenithstar 61 later this year as as it's small and light and has the quality you expect from William optics at sub £400

[toxic]

why not just use the camera and lens for now if you want to do wide field imaging just get a skywatcher star adventurer or some thing similar and put your camera and lens on it then save even more money for later on.

 

[happy-kat]

If you do want a telescope then an ST80 gives great grab and go and could be mounted on an existing photo tripod with a bit of adapter thought and later it could be a guide scope on an imaging rig. If used for imaging there would be chromatic aberration but narrow band imaging mitigates that.

[Graham F]

Thank you all for your interesting replies. I have considered using one of my lenses but as I am a semi professional landscape photographer (I also own a Nikon D800 but 36mp full frame produces huge image file capacity) most of my quality F2.8 lenses are in the wide and super wide range.

I own a Nikkor AIS manual 180ED F2.8 lens and a cheap Nikon 70-300 F5.6 but here's the thing, I know from experience that most of my lenses require stopping down at least 2 stops to achieve a good overall sharpness particularly at the edges and I am led to believe that diffraction from the aperture blades (the nikkor has 9) causes problems with light formation (stars)?

I could always put a 2x converter on the 180 but again that slows it to F5.6, probably also degrading the 180's optics as the converter is not of good quality. (Landscape photographers generally don't need them)

 

The suggestion of the skywatcher star adventurer is brilliant as prior to this tip I'd not know about it so thank you and also Carol, the suggestion of the William Optics 61 is also well received.

I may well go the star travel complete kit first (as already have a stable set of legs?, and also a good tripod) and see what I can produce with the 180ED and then go for the WO61, my only concern is that I assume the WO is only a 61mm diameter aperture and wondered if this is enough over say the SW ED80 or SW 102ST for light gathering?

again, thank you for your valued time.

im just off to,do some research on the WO61....

i have enclosed a few sample shots of my landscape photography just for your interest. 

regards Graham.

[happy-kat]

I'll read it better later but wanted to say use your ed lens stop it down either make a card board mask or use a step down ring either would remove defraction spikes.

Edit: love Ightham Mote looks a very interesting place the lines are really pleasing.

Step down rings are inexpensive and you may already have some and would remove defraction spikes and keep the great ED quality as there's no extra glass.

This is a useful CA chart. The startravel range is f5. Sorry I got confused was this for observing or imaging?

 

[Graham F]

8 hours ago, happy-kat said:

I'll read it better later but wanted to say use your ed lens stop it down either make a card board mask or use a step down ring either would remove defraction spikes.

Edit: love Ightham Mote looks a very interesting place the lines are really pleasing.

Step down rings are inexpensive and you may already have some and would remove defraction spikes and keep the great ED quality as there's no extra glass.

 

Thank you for your kind comments regarding my images.

Having done some further investigation/surfing I have been reading reviews that state the SW star adventurer is ok for lenses up to 200mm and a medium weight DSLR, however some reviewers have mentioned that its tracking is quite wild at times and that the polar scope can not be used once the camera is mounted. (I'm wondering if this is a problem should any adjustments be required to its polar alignment once the photographic kit is mounted? Taking the photographic kit off the mount again isn't something I would cherish! 

I have also looked at the SW EQ 3-2 pro with the GOTO/Track and wondered for roughly the same money whether this would be a better option? I know that I am doubling up on the tripod legs part but wondered if this all in one manufactured solution would work more accurately to mount my D600 or D800 and a medium sized refractor say an ST80 or  ST102.

The trouble I am finding doing further research is that obviously these viewpoints are personal and most people have significantly more money to spend on this hobby than I do, I understand this as I have spend £ 1000's on my photographic equipment, however I can justify that as I have more than broken even over the years with publications. I cannot justify spending the same on something mealy for pleasure / hobby.

Thank you for all your replies, please keen your answers to a realistic budget. Kind regards, Graham. 

[happy-kat]

I see the ST80 used more often as a guide scope then it's sibling. Second hand goto mounts do pop up. I had thought I'd seen a post where polar alignment could be done with camera on maybe it was a modification there are several active star adventurer users stargazing tim is one member who springs to mind using camera and lens there are lots using it. There is also a long thread on users just imaging with the eq3-2 you might like to read that and see what they are achieving. Star Adventurer images tend to be post ad hoc there is no dedicated thread I don't think.

link added

[AstroKane]

Hi Graham - If you are looking to keep your budget down (which can be hard) and by the sounds of it you already probably have some quality DSLR lenses I would go down the DSLR route for sure.

When I started out getting into imaging DSO's I didn't have any kit so had to buy the tripod, DSLR, tracker etc - so you have already won half the battle .

As well as the Sky Watcher Star Adventurer check our the iOptron SkyTracker Pro (about £350) - can take a DSLR and lens up to 3kg which should be man enough. I have the older basic version.

Id imagine with darker skies and better lenses the results would be most pleasing and would let you practice all the other bits of processing that comes with the DSO work.

I thought I might attach an image I shot of the Orion Nebula last year which may help (I am learning DSO imaging myself so it isn't the greatest)..This was taken with a canon 750D and stock 300mm lens on the older iOptron Sky Tracker using a manfrotto tripod- What I like most about the DSLR route is  it is really easy to set up and if you eventually do upgrade to mounts and telescopes, you will always have the DSLR and tracker for on the go Astrophotography! 

Hope this has helped and clear skies with whatever you choose.

[Graham F]

Great Photo (looks good to me as a novice) thanks for your input, I never rush into these sort of decisions. More research, more coffee and midnight oil!