Andromeda galaxy - fuzzy blob

[great_bear]

OK but the 3.3 reducer is SCT only bnd CCD only, or am I wrong?

Olly

I've not tried a 3.3, but I'd expect it to be able to fully illuminate some shorter-length 1.25" eyepieces, tripling their focal-length. It depends on the field-stop size. Whether that's useful functionality or not depends on what other eyepieces someone has.

Perhaps someone else can test this out, and say what's the longest focal-length eyepiece which remains unvignetted with a 3.3 reducer in place? I can't imagine it's very high - probably a 12 or 15mm Plossl or thereabouts.

[Gaze Away]

Hi Olly, Im a newbie and found this link on here.http://www.12dstring.me.uk/fov.htm

You may have it but as a newbie I found it to be very helpfull.

My first bit of advice on site ever lol. It nice to at least think im giving something back.

Andy

[ollypenrice]

I've not tried a 3.3, but I'd expect it to be able to fully illuminate some shorter-length 1.25" eyepieces, tripling their focal-length. It depends on the field-stop size. Whether that's useful functionality or not depends on what other eyepieces someone has.

Perhaps someone else can test this out, and say what's the longest focal-length eyepiece which remains unvignetted with a 3.3 reducer in place? I can't imagine it's very high - probably a 12 or 15mm Plossl or thereabouts.

I remember trying a 3.3 in our ten inch SCT and being able to see nothing at all. I can't remember the EPs we tried but I'm convinced that it is not a visual reducer and is next to useless for CCD as well! On a webcam sized chip, OK, but those are largely a thing of the past these days. OPT, the astro suppliers, agree with me, viz 'For CCD imaging only, not for visual use.' (From their website.)

Calculating a field of view at F3.3 is easy. But will it work? Not if the baffle tube is the thing which limits the field of view.

If all you had to do to set up an F3.3 imaging rig was buy a big SCT and one of these reducers, believe me, there would be no other imaging telescope ever seen on the DS imaging board... The fact that they are never, ever, seen is because they don't work. If anyone wants the one I was given they can come and collect it!

The happy way to SCT widefield is with a 2 inch visual back and a nice 2 inch Nagler. Or, if you insist, Ethos!!

Olly

[GazofCorra]

That is why i sold my 200P dob as once you have seen 1 fuzzy blob they all look the same (oh look another fuzzy blob, detected with averted vision, yippy) the only great views of DSO's are with CCD, what let's us down every time unfortunately is our own eyes.

Planets however do look awesome with our own eyes and so does the moon.

[AstroKerr]

On 7/17/2011 at 01:57, brantuk said:

What's fascinating about andromeda is the fact that the light from the fuzzy blob you're seeing, first started it's journey when dinosaurs walked the Earth. 

 

No dinosaurs - M31 is only 2.5Mly away - our Gelasian (beginning of the Pleistoscene) period. Homo Habilis scavenging. Dinosaurs had been dead ~60MY.

 

[John]

1 hour ago, AstroKerr said:

No dinosaurs - M31 is only 2.5Mly away - our Gelasian (beginning of the Pleistoscene) period. Homo Habilis scavenging. Dinosaurs had been dead ~60MY.

 

Thanks for that

[brantuk]

Yeah - I was corrected on this six or seven years ago when I was a relative newcomer and got mixed up on that point lol. Thanks for reminding me.

[ollypenrice]

26 minutes ago, brantuk said:

Yeah - I was corrected on this six or seven years ago when I was a relative newcomer and got mixed up on that point lol. Thanks for reminding me.

But M31 is older now...

lly

[Padraig]

This fuzzy blob got me hooked on astronomy 1yr. ago after viewing through a pair of binoculars. Was expecting to great things when I purchased my 6"sct. Spent weeks looking for m80 & m81, only to find out they were too low on the horizon for that time year to see clearly 

started to look at other dso's then : ring nebula , heculas cluster, Orion Nebula and only recently found the blinking nebula which was a great buzz to find. 

Thats the great thing about this hobby…discovering dso' s yourself imho. 

Ps : did get a good view of m80/81 last January. 

Stick with it angelika, some nights are good and some are just amazing

from : newbie - one year

[Stu]

This thread started nearly as long ago as the dinosaurs were around anyway , very nearly a digital fossil  

[Padraig]

That's the probe with reading using "adverted vision" , I've  never check the date ! ?

[JamesF]

It's the ones (rarely on this site, to be fair) who read with averted thinking that are the real worry.

James

[25585]

Nice to find the thing at all all with most DSOs. Also Uranus, Neptune, Mercury. 

It was the first reality of optical for me. What you see is way different from Astro photos, even old photographic black & white plates. 

[Charic]

On 17/07/2011 at 09:48, obscura said:

The fuzzy blob was my experience too with an 8" SCT. A little disappointed and sold the scope.

I know this is an older thread, but it's a good job I didn't do the same with my 8" Skyliner!

From my back garden, M31 is just a slight misty patch, even the core is barely discernible, and as those before me mention, its quite a turn off, having seen M31 in images elsewhere, but selling the scope is quite a drastic option, I just  wonder if the conditions could have been better?  

Folk often mention the importance of darker skies? Now for me, darker skies are simply anywhere where I can't see direct man-made lighting, and let it be  a Moonless night, that's a dark site for me, however, under these conditions, on a good Winters night,  here in Scotland, to be honest, I'll see too many star's, and their so bright, casting body shadows on the ground???  even the major constellations get swamped, but M31 is  clearly visible, filling the eyepiece, a joy to look at, when at home, its clearly miserable.

Conditions need to be met in order to get the best from our scopes, finding/having the best is key!

 

[Stu]

26 minutes ago, Charic said:

I know this is an older thread, but it's a good job I didn't do the same with my 8" Skyliner!

From my back garden, M31 is just a slight misty patch, even the core is barely discernible, and as those before me mention, its quite a turn off, having seen M31 in images elsewhere, but selling the scope is quite a drastic option, I just  wonder if the conditions could have been better?  

Folk often mention the importance of darker skies? Now for me, darker skies are simply anywhere where I can't see direct man-made lighting, and let it be  a Moonless night, that's a dark site for me, however, under these conditions, on a good Winters night,  here in Scotland, to be honest, I'll see too many star's, and their so bright, casting body shadows on the ground???  even the major constellations get swamped, but M31 is  clearly visible, filling the eyepiece, a joy to look at, when at home, its clearly miserable.

Conditions need to be met in order to get the best from our scopes, finding/having the best is key!

 

Charic, reading this, if you ever complain about light pollution again I shall invite you down to London to show you what it is really like!!  

Get yourself that 12" dob and go and enjoy those skies!

[Charic]

29 minutes ago, Stu said:

I shall invite you down to London to show you what it is really like!!  

It was raining on 22 August? I was hoping to meet up with the Baker Street folk at Regents park, but yes I know what Londons like, a bit similar to my street, when the leaves fall, yet I did see my first sighting of Venus this Year from London.

I've all but given up on the larger scope (today) but who knows, shopping trip tomorrow in Glasgow! But I need to 'borrow' or peer through a 12" aside my 8" .
If the difference was clearly noticeable, from the home site, then the 8" could go, simply because I do most of my observations from home, and the 12" would be an improvement for visual use only. Even a 6" Skyliner would provide better images at a dark site over my present setup. its great having darker skies, close by, its the time afforded  these days (very little) and the effort to get up and go, that's the main issue, and having the right conditions, otherwise could be a wasted trip, and its probably more of an issue lumping a 12-16" dob about.
Anyhow, have I  mentioned going to a  really darker site, the Stars  are so much...................
 

[Stu]

15 minutes ago, Charic said:

Anyhow, have I  mentioned going to a  really darker site, the Stars  are so much...................

Grrrrrrrr.....!!!!  

Get a 12" or even 16" Truss dob and get out to that dark site. There is no question, a 12" will show you a LOT more than an 8"!

[Charic]

46 minutes ago, Stu said:

There is no question, a 12" will show you a LOT more than an 8"!

I agree, away from home, even a 6" would  be great, but having bought and expected much more from premium eyepieces, I'm of the same inclination that there may only be a subtle difference when using the larger scope from within  the back garden, under the same  light pollution /  seeing conditions. It'll need more than a subtle difference to warrant any upgrade. Both scopes away from home, yes it's a no brainer, the larger scope will win!

The tree's are shedding their leaves quicker than I'm typing, allowing more sodium light to enter the garden, but  soon the sodiums are  supposed to be getting exchanged for LED's and from what I have seen so far, with the LED's there's  much less  light spread, so if they use the same poles , then there could be an improvement here, but if the poles are higher, it's going to be a problem! 

[Stu]

21 minutes ago, Charic said:

I agree, away from home, even a 6" would  be great, but having bought and expected much more from premium eyepieces, I'm of the same inclination that there may only be a subtle difference when using the larger scope from within  the back garden, under the same  light pollution /  seeing conditions. It'll need more than a subtle difference to warrant any upgrade. Both scopes away from home, yes it's a no brainer, the larger scope will win!

The tree's are shedding their leaves quicker than I'm typing, allowing more sodium light to enter the garden, but  soon the sodiums are  supposed to be getting exchanged for LED's and from what I have seen so far, with the LED's there's  much less  light spread, so if they use the same poles , then there could be an improvement here, but if the poles are higher, it's going to be a problem! 

What is your NELM at home? Or an SQM measurement? You can normally shield yourself from the glare of street lights, if the sky above is good then it will be worth it.

[John]

1 hour ago, Charic said:

I agree, away from home, even a 6" would  be great, but having bought and expected much more from premium eyepieces, I'm of the same inclination that there may only be a subtle difference when using the larger scope from within  the back garden, under the same  light pollution /  seeing conditions. It'll need more than a subtle difference to warrant any upgrade. Both scopes away from home, yes it's a no brainer, the larger scope will win!....

 

The difference you will see will depend so quite a large extent on you. If you work at it, pick your targets and hone your observing technique you will see more than subtle improvements. If you never try, you will never know. The ball is in your court rather than for others to pursuade you I feel.

[Charic]

56 minutes ago, Stu said:

What is your NELM at home? Or an SQM measurement? You can normally shield yourself from the glare of street lights, if the sky above is good then it will be worth it.

I do hide in the shadows,  as often as I can, or inside the tent (which is missing at present?) but there's no mistaking, getting away from the house is the better option, infact (how time flies) We had the same conversation two years ago, back then it was about NELM 6.1 on a good night!

I've  also discovered a patch behind the houses, that's darker to the eye as it hides most of the street light, not all, but lugging the Skyliner is the issue, could be just lazy!  I should get an old  sprung perambulator for the dob!

[Charic]

22 minutes ago, John said:

If you work at it, pick your targets and hone your observing technique......

It's this advice that has helped quite a bit, just by taking more time, you can see more!  I can sit for hours or more trying to find a single target, knowing that I'm fighting  against the street lights here. My last three sessions were trying to visualise M101 Pinwheel Galaxy, and M51 Whirlpool Galaxy, I know where to look, but I just don't see them from the house, with Ursa Major in roughly my NNE location about 45° elevation, the best position for seeing the constellation with 5 street lights to compete with. 

Away from home, a short drive in the car, some of my targets are like beacons! such is the difference between the two sites. I have no issues with what's achievable away from home, its whats achievable from home that needs some, if not at least a +50% improvement.

[Stu]

9 minutes ago, Charic said:

Away from home, a short drive in the car,

Most of us would sell a limb in exchange for dark skies a short drive from home , so would be good to hear of some reports of sessions you have there.

[Charic]

...forgot to add, the biggest issue to-date has been the weather, but that affects everyone. It's just not good enough on Friday nights (or so it seems) my main day of the week that allows for observing.
I also have a very limited view. Take the 'Trees' landscape in Stellarium, add some houses south facing and you'll have an idea, but looking around the tree tops and structures, on a good night, Ursa to Cassiopeia  is my limit, with Polaris almost straight up.

[Charic]

5 minutes ago, Stu said:

.....some reports......

The next time that conditions allow, I'll try to take  better notes, maybe try the Nikon.

It was the sole reason to visit the Baker Street meeting in August, to peer through a 10-12" scope under Urban  skies/lighting. 
Also, when reports come in from those that visit places like Skye, I know what their experiencing