Andromeda!

[Tom2012]

Finally found it with the dob! Was really hard to find! Took me ages! I was (I shouldn't have been) expecting to see some swirls and the centre of it but its just a little bit more fuzzy than my 15x70 celestron bins!

Would a Barlow lens improve and introduce anymore detail? I've used the 10mm and 25mm stock EP's.

Thank you.

Tom.

[wookie1965]

Ive tried a Barlow with my 8 mm BST and it didn't give me any better viewing i think i will be better looking from a dark site and better viewing conditions. Most likely you will be the same.

[Steve Ward]

M31 is about 6 Moon widths across so you really want to stick with the 25mm EP.

For comparison here are 2 pics I recently took with the same lens set at 190mm FL.

Well dark adapted eyes , a dark viewing site and plenty of patience and the detail will start to appear.

Don't expect photographic views through the EP though , but you should be able to make out some dust lanes .

Steve.

[wookie1965]

I thought it looked better through my 18mm than my 8mm i could make out a lot more just looking at it the magnification doesn't help that's what i was trying to say.

[Qualia]

I'm only using a small 4" f/10 but I've found that if you increase magnitude, the object will cover a larger area of the EP's image - so with something like Jupiter, say, the affect of magnification does make Jupiter appear to get bigger and so you can go further into more detailed study but....what is also happening is that the light is getting more spread out over a larger area, so it gets thinner and the brightness drops.

Now upping the magnification on Jupiter to a certain degree is one thing, but it's only about 0.0000621 light years away. If you take into account that M 31 is a lot further away, some 2,500,000 light years away, you begin to appreciate that if you start whacking up the magnification too much, what you're really doing is spreading that light over a greater area, so you're decreasing its surface brightness.

For purely visual practice, with M 31 in dark skies I'm using about 40x and wished at these moments I had a shorter length frac or a nice 30mm EP.

[Pingster]

Well done! Generally the view of androm wont get much better than you have already achieved. Believe me i have viewed it in 100mm bins, 8in, 12in and 16in dobs. Generally from most skies below 6maga fuzzy blob is the best you will get. Having more apperture will make that blob brighter and finer in resolution. So dont rush out and buy any expensive lens. It really wont make much difference. In a 25mm plossl you will more or less see the same detail i see in a 31 nagler.

The only time i saw it even 10% close to a photo was in wales mag 7 skies, i was able to see 3 dust lanes in my 16in scope. And when people say dust lanes take care as it is the dust lanes we are describing, but thru the eyepiece they are not "dusty in appearance", but we can see two dark features dividing the fuzzy blob into 3 distinct bands, hemce the dust lanes.

So my advice is to get out to wales or mag 7 skies if you want the best views with your current setup. I have not since (1year) seen adrom as good as my view in wales. As simple as it was, i was amazed. But i know my friends would not be as impressed

as i was!

[andrew63]

Actually binoculars under good seeing are excellent for M31!

andrew

[cotterless45]

It's an awe inspiring group (M31,M110 and NGC206) at low magnification, neat,

Nick.

[Tom2012]

I couldn't see M110! Just a fuzzy Andromeda.

I'm going to try it with a 2x Barlow and the 25mm EP when I can!

Thank you all for your help and time. Very informative!

Tom.

[estwing]

it's all about the dark skies mate

[swamp thing]

it's all about the dark skies mate

^^^This^^^

[Hawkeye]

M31 is about 6 Moon widths across so you really want to stick with the 25mm EP.

For comparison here are 2 pics I recently took with the same lens set at 190mm FL.

Steve, just checking, are you saying these photos were taken through a camera lens at 190mm, no scope?

Cheers Paul

[Steve Ward]

Hi Paul ,

Shot with the Canon 75-300 EF Zoom lens at 190mm and the 1000D.

I shot the Moon just as a direct size comparison after it started to affect the subs I was taking of M31.

Meant to paste the two together but not worked that bit out yet , still not seeing eye to eye with PS . . . .

Steve.

[Stu]

Here's a similar image I grabbed off the interweb, shows the comparison nicely.

Low magnification, wide field and dark skies are what you need for M31, it's big!

Stu

[Steve Ward]

Not quite sure how I got there , but a little play with Layers and things got me this . . .

Couldn't have guessed at the framing much closer . . .

Steve.

[John]

Nice images those. They neatly illustrate how wide the FoV needs to be to fit the whole of M31 in - my 31mm Nagler with my 102mm F/6.5 refractor gives me 3.83 degrees which is still not wide enough !. It's also nice to use a lower power / wide angle eyepiece to fit M31, M32 and M110 in the same field of view

[Steve Ward]

I find they all fit perfectly on the chip with the ED80 and F/F but I really like the wider field myself .

I could do with the 200mm f2.8 really because the zoom's not the greatest bit of glass , but you have to draw the line somewhere .

Steve.

[Stu]

Nicely done Steve

Stu

[Stu]

Hi Qualia, at f10 that must be challenging to fit too much of it in the fov, what ep do you use and what is your focal length?

The difference in surface brightness is huge. Jupiter is -2.9 max, size of 50 arc seconds max. Andromeda mag 3.5 ish (IIRC), size around 190 x 60 arc minutes.

Stu

[allcart]

very informative thread. I never imagined M31 was so big. This might explain my lack of success with my shots at 520mm and 1100mm with my dslr. It appears that I am probably right inside m31 so no amount of processing will show this type of image. Will deff try 200mm at the weekend and see what happens. Thank god I read this before I wasted another night.

[Stu]

Sounds like a good plan allcart

There are some useful simulators around which let you see what your setup will show in terms of sky area based on sensor size, focal length etc. Will post a link if I can remember it!

Looks like 200mm should be fine though

Stu

[allcart]

Seems like I might get somewhere at last, having read this topic. I'm just hoping for a clear sky over the wekend to try uot my rig.

the last time I tried M31 at 525mm it looked like a very small fuzzy bit in the frame so i thought I might need to shoot even closer. Its now apparent that magnification isn't everything.

I have so much to learn.

[Stu]

We've all done it allcart.

When I got my mak a long time ago now, I tried to view M31 through it and was not overly impressed. Turns out my field of view was under 0.5° so I had very little chance of seeing much! Much better at 3.6° through my frac at a dark site. You live and learn

Good luck, and hope you get some good skies soon

Stu

[Stu]

This should be a link to the field of view calculator which is handy.

http://www.12dstring.me.uk/fov.htm

I use one on my android smartphone called foviewer which I find very good too

Stu

[allcart]

Had a really clear sky last night. Could see it quite clearly through me 16x50 binos so I took some pics at 200mm iso 400. I thought i had the cam set to f/3.2 but it seems to have been f/5.6 instead. Fingers crossed.