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CoolJWB

Possible Deep Sky problem?

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Hello.

I have recently bought a Skywatcher explorer-150pds for some deep sky photography and observation. The only problem I've had is that i won't see much deep sky objects and the best I've seen through the telescope is a blurry M31 Andromeda.

I am wondering If my telescope Isn't that good for deep sky observation. I've not been able to watch Jupiter, Saturn or any kind of planet yet. The only thing is the moon. 

Can someone please tell me If i got the wrong type of telescope!

-William

Btw the picture of the moon is with my Sony Xperia through the telescope.  

PicsArt_09-22-09.57.38.jpg

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Nothing wrong with a 150P-DS for imaging. A bit big for a first 'scope perhaps (The 130P-DS is more often recommended). What mount are you using it on? Anything less than a HEQ5 level mount may be a bit wobbly for a 'scope of that size. Should be OK for visual too, though the "dob mob" will go on about aperture, if you want to do imaging it'll be fine.

M31 *will* look like a fuzzy blob, even in a 150mm 'scope. Your picture of the moon isn't too bad, a bit out of focus perhaps, but other than that....

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M31 is nothing but a small blurry wispy patch viewed through an 8" (200mm) telescope if the conditions are not perfect, like viewing from my light polluted garden.
Take the scope to a darker site  and the difference is  more than stunning, so much so, that I cant get M31 to fit inside the field of view in my 70° Panaview?

Try M31 again from a darker site.

Edited by Charic

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For observing (with eyepiece as I guess you are getting afocal images at present) you may need a short extension tube, The mirror is relocated to enable the prime image to fall directly on the camera sensor, but that means that an eyepiece is too far inwards. So the necessity of a short extension tube to move the eyepiece back out, and so get a sharp image.

Would have thought they would have supplied one but maybe not. ES and Bresser seem to make their scope biased towards imaging and they supply a short extension as a standard item usually. Guess Skywatcher do not.

M31 is big and fuzzy, you may not have it all on the sensor and focusing may be a problem, just to dim to achieve a sharp image. And if as I suspect it is afocal but no extension tube the image will not be sharp.

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Hi

You might need to rethink your aims! There's no one scope that does everything. A 150pds, although a bit heavy and bulky, is fine for imaging DSOs when attached to a suitable tracking equatorial mount, e.g. heq5 Pro or Neq6, and with autoguiding and a decent imaging camera. It's not much good for observing or imaging planets as it stands. You really want a much longer focal length for planets but you could make do with a suitable Barlow. Most nebulous DSOs are not more than fuzzy blobs to observe - imaging can reveal their true glory and colours. Star clusters should be rewarding to observe - eg M45, the Pleiades and the Beehive Cluster, M44. It's really worth reading Steve's book if you want to get into imaging.

Louise

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Your sky is too bright. Take the scope to a place where you can see M31 with the naked eye and it will look great through the telescope. From a light polluted site it never shows as more than a fuzzy blob, no matter what kind of scope you look through. Though even fuzzy blobs can be very interesting if you're prepared to use a bit of imagination.

Edit:

I notice that you're in Skelleftea in northern Sweden. Maybe light pollution isn't an issue: as long as you can see the Milky Way your sky is good enough for satisfying DSO views. If that's the case then maybe your disappointment with M31 is just because you expect too much too soon. The views are never like photographs. Get used to the scope, learn to tease out everything your eye can detect, and you'll find you can see a lot. Try the Orion Nebula, M42, and for galaxies try M81/82.

Edited by acey
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12 hours ago, DaveS said:

 Should be OK for visual too, though the "dob mob" will go on about aperture,

 

Err no. 

The Dob mob will go on about taking your scope somewhere dark. 

Nothing makes more difference to visual deep sky observing as the quality of the sky you are observing from. A 6" scope from a good dark sky site is a superb instrument. 

 

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55 minutes ago, swamp thing said:

Err no. 

The Dob mob will go on about taking your scope somewhere dark. 

Nothing makes more difference to visual deep sky observing as the quality of the sky you are observing from. A 6" scope from a good dark sky site is a superb instrument. 

 

 

Yes a dark site is the way to go?

But taking a 20" or 22"  Monster Dob does give you that Extra seeing ?

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I've owned a couple 150PDS over the years and was happy with both. They are a great little scope for quick grad and go observing on an AZ4. I have seen many a good image taken with them too but everyone seems to favour the smaller 130PDS for imaging since it's release a couple years ago. I feel you may be left a little wanting visually with the 130PDS though where are a 150PDS under dark skies will offer up some better observation sessions than under light polluted skies. Unfortunately it would appear you can't have the best of both worlds as smaller wide field scopes work better for imaging and huge light buckets work better for visual observing. You kinda have to decide what you want most if you can't afford both. 

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I have a skywatcher 150 discovery and had no issues with DSO but as others have stated it needs to be at a dark area. Plus out of interest when did you try looking as it has been full moon the last few nights which will instantly render looking for most things a pointless task! I would try again in a couple weeks when it is a new moon.

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Hi its probably your expectations

what you see in the ep is not what the camera sees on a long exposure I'm new to this as well and I must admit I was rather disappointed when I had seen m57 in the ep however under the right conditions (which can make a vast difference) it's fantastic and a  few long exposure shots Stacked and processed you can really see it in a different light

Keep trying because it's not easy but you will get there it's also extremely frustrating at times but when you get it right makes it worth while

Regards Baz

 

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On 2016-10-16 at 22:24, CoolJWB said:

Hello.

I have recently bought a Skywatcher explorer-150pds for some deep sky photography and observation. The only problem I've had is that i won't see much deep sky objects and the best I've seen through the telescope is a blurry M31 Andromeda.

I am wondering If my telescope Isn't that good for deep sky observation. I've not been able to watch Jupiter, Saturn or any kind of planet yet. The only thing is the moon. 

Can someone please tell me If i got the wrong type of telescope!

-William

Btw the picture of the moon is with my Sony Xperia through the telescope.  

PicsArt_09-22-09.57.38.jpg

Thanks for all the answers, I have sadly no clear sky for the next 10 days so yea.

I won't be able to get to a less light polluted area because like acey said Im in Skellefteå in sweden and I live in Drängsmark that is a small village 2 and a half mile out from Skellefteå. 

After about 23.00 they shut of the street light and the sky goes clear. 

My main goal was to photograph DSOs If I wasn't clear from the beginning. I don't don't care about Planets I just don't seem them as facenating as DSOs. 

The only problem I have now is trying to find a T-ring to my Olympus E-420 and I say it was though. But I think I found one.

Anyways thanks for the tip that I should change my shutter speed on the camera but the E-420 has a max of 60 so let's see how it goes.

Im going to try my best to find a dark place and try again but I don't think that's gonna happen soon because the weather gods don't like me... I'm going to get a T-ring and adapter and snap some 60 sec pictures If I can get the T-ring soon. Thanks for all the help and wow Im impressed that I got response so quick. 

Thanks for the help and I will hopefully return with some good pictures!

-William

I will try to stack the photos I get but I don't know much about stacking XD

Edited by CoolJWB
Detail

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A dark spot can be as simple as finding a shadow in the garden? Its your eyes that need the shielding from ANY stray lights, be that from the houses, cars, street lights.
Covering your head with a towel or a Hoody! will help to keep the light levels down, or hide inside a tent? Once your eyes are dark adapted, spend some time at the eyepiece, and you may surprise yourself, but as soon as you look at a white  light, Bam! another 20 mins to wait for the eyes to dark adapt again

There is nothing better than being away from man-made light pollution, but  just as easy to hide in the shadows.The fact that the street lights go off is good. My local street light looks like a giant fish tank, with its upright orientation, and the light just floods out everywhere. :glasses9:. Ive  even used Sun glasses or a patch to help  quell stray light, just try anything.

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A t-ring and prime focus imaging is the way to do it. Actually 60 seconds is fine, I presume that at this time you have no guiding. So 60 seconds will be about the maximum you could realistically expect.

You will need also an intervalometer or remote timer - same thing 2 different names. Personally I would set the camera to an exposure of 40 seconds (keep a bit in hand). Then set the intervalometer for a 5 second delay (does nothing for 5 seconds and allows you to put the intervalometer on something) then have it set to a 40 second exposure and an additional 20 second Wait, finally set the number of exposures to 10 or 12.

Overall effect is that you will get 10-12 exposures each of 40 seconds duration, each exposure will take 60 seconds to complete and before the next one gets going, The 20 second wait allows a bit of cooling for the camera sensor, it is also "padding" for the durations involved. If both camera and intervalometer were 40 seconds and no wait then it can happen that the intervalometer starts the next exposure before the present one has completed. Usually the camera freezes.

Stacking is fairly easy in it's simplest form. Download and install Deep Sky Stacker, create a new folder and put all the exposures in there. Open DSS and select all the exposures for Stacking (this is a bit sort of not clear the first time) then basically tell it to stack the lot. You can reduce the number of stars that it aligns on but cannot recall the details. It will eat up the processing time and out the end comes a stacked image. DSS will stack jpegs. There is no or limited processing in DSS so just stack.

If you want Darks then I take about 1/3 to 1/2 as many darks as exposures. Put cover on camera lens, change number of exposures to say 5, put camera and intervalometer in the fridge, press the go button and close fridge door. 5 minutes later you have some darks. Suggest that you stop there until you get more esxperience.

It will be worth getting say 10-12 exposures of one object, then reset the scope to something else and getting 10-12 of another. so initially 2 or 3 targets is a fair idea. Then take all the exposures home for stacking later. Take binoculars, when the scope is getting images you may as well have a look around.

 

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13 hours ago, CoolJWB said:

 

After about 23.00 they shut of the street light and the sky goes clear. 

 

Now why do we not have this in the UK. Cheaper for the council so our council tax should come down..cough...cough..and great for us lot.

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They do.  Lights go off in Ripon at midnight but they leave some on where there is potentially a safety risk.

Edited by Owmuchonomy

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Hello! I went out today not knowing that I didn't have much time but still I snapped some long exposure photos. I took about 40 photos with 10 seconds exposure ISO 400. When I stacked them I got this awesome photo "Vega Processed" that you can find In the attached images. Also I snapped like 10 photos with 10 second exposure ISO 1600 on the cigar galaxy and got the best stack I've ever gotten. Still The Vega picture could be better then the Cigar Galaxy because of the sharpness In the Vega picture. But still the Cigar Galaxy is awesome!

Why I posted this is because Im just saying that now I think Im ready to take on the big universe with my "small telescope" and that I will return If I ever have more problems (probably) or else if I don't have Im probably going to return when I know more and have explored space and maybe help others to get going with their telescope and so on. 

 

Vega Processed.png

Cigar Galaxy.png

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