Don't be fooled!

Discuss the greatest threat to amateur astronomy today

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pete-6
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Don't be fooled!

Post by pete-6 »

...by which I mean, even if you can see the Milky Way it doesn't necessarily count for much.

The two images below (both of NGC7331) were identical exposures (3 minutes at ISO 1600, Canon 350D at prime focus through the Europa-250):
Image
The one on the left taken on 28/29 Aug. in my garden in Burgess Hill (10 miles outside Brighton), and the one on the right on 2/3 Sept. at my place in South-west France. In between the sessions I loaded all the kit up in a white van and drove it all the way down there.

Ignore the fact that one of the pics my alignment was utterly shot up so the stars are trailing badly. Just look at the glow - the images speak for themselves!

The point is, while doing the image in Sussex I could see the MW fine, so I assumed that LP wouldn't intrude. How wrong can you be!

Sorry this is just a moan instead of a constructive suggestion as to 'what can we do about it'. But if you read the message in the above piccies, the whole of SE England seems to be a waste of time. I hope someone will prove me wrong!
Pete
Cliff
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Post by Cliff »

Dear Pete-6
I think I see what you are saying. Unfortunately you have high-lighted a problem many of us have to put up with. We can only keep plugging away and try our best.
Best of Lucjk from the Grumpy Old Codger Cliff
pete-6
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Post by pete-6 »

Cliff,
Sorry if this seemed a bit smug of me! Astronomy (well, especially if you go for medium or large telescopes and astroimaging) is an expensive hobby and part of the expense involves travelling to the 'best' places you can get to! I'm one of the lucky ones, my wife and I having just set ourselves up with our maison de retraite and looking forward to the day when I can spend more time down there!

Maybe it was a bit hasty of me to say the area around me here in Sussex is a waste of time. A lot can be done with filters I suppose. The thing that threw me was, on the night that I took the left-hand pic., I have down in my notes that it was a 'magnitude 5' night with the Milky Way clearly visible! Despite this, as you can see, a prime focus shot of 3 minutes or more at 1600 ISO is virtually useless. Perhaps there was a lot of thin high cloud throwing back the LP glow, which I couln't see with the unaided eye. I suppose ordinary visual work (non photographic) would have been OK on that night. I didn't try.

But it goes to show, the human eye can be a poor judge of how good your images are going to be. You just have to do a few trial shots.

Anyway, if ever you you (or any of you others) can fit in a trip to my part of France coincident with one of my visits, you'd be most welcome! We can put three up (one double and one single room).
Pete
jeremyll33
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Post by jeremyll33 »

Where in the SW is it?

My family owned a place down there years. Stars were amazing.
pete-6
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Post by pete-6 »

Lot region, north of Agen and west of Cahors, near Villeneuve sur Lot. Not as good as the celebrated triangle noir (NE of Cahors, couldn't find a suitable house there), but not bad nonetheless.
Pete
mutleyeng

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Post by mutleyeng »

hi guys,
I'm a complete novice here, currently seriously looking into getting an 8"gps scope to be used in the S.E of england.
At the moment i am just trying to do a little research into what i can realistically expect to be able to view given my regions vewing magnitude limitations of somewhere between 5.2 and 5.8 on a good day.
Now please ignor me if im talking tosh here, but looking at the image posted above, dosnt that look more like emmissions polution rather than the effect of light polution?
I have recieved advice that outside of winter months, deep sky viewing is only really practicle the day after the passing of a cold weather front...best within 24hrs and deteriorates rapidly over the next couple of nights. Apparently a prevailing N.W wind seems to help with transparency too, but cannot find a good reason why that would be.
Cliff
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Post by Cliff »

Dear Pete-6
Obviously I do not have experience of your local skies 10 miles from Brighton but I can appreciate your English sky is terrible compared with the South of France. However, unless you can get to france a lot I would not give up on England entirely yet.
For about ten years I tended to concentrate on telescopic visual observations of planets because my local light pollution made visual Deep Sky observing quite frustrating. However, I got a CCD camera in 1997 and that revived my interest in the Deep Sky. Of course it would probably be much better in your French location, but as far as I am concerned these days I think 95 percent of my observing is and will continue to be made from here, 4 miles north of the centre of Manchester.
I think that you have done very well with both your pics of NGC7331. Incidentally on a decent night (say limiting mag +4.3 in Ursa Minor I can visually observe NGC 7331 reasonably from here using an 8 inch SCT. Funnily enough I was actually looking at a nice CCD image of NGC7331 taken by a friend in a light pollued location similar to me,using a 10 inch SCT and Starlight Xpress MX5-12 camera. I think he had stacked 5 No two minute exposures. Of course had he tried to take a single 10 minute exposure he would probably have just got a completely white image.
I think "one shot" colour cameras are great but I personall think to get the best results long exposures or (particularly from light polluted urban places) many stacked exposures are need to get the best results. To avoid too much frustration for urban based CCDing I think the simple answer is to use a decent Buz & Wuz astronomical CCD. I do like to see coured astro images although my ideas about colour Deep Sky pics might not be liked by a lot of people!
RebeccaM
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Darkest skies

Post by RebeccaM »

Can anyone nominate their favourite spots in the UK for star gazing with minimum light pollution? I am a journalist writing an article for fellow novice astronomers, and I'd like to mention some specific areas where you might get a better look than others. Many thanks.
joe
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Post by joe »

Hi Rebecca,

Anywhere north of Loch Lomond really and especially the islands but that would be part of a holiday I suppose for most people. My best ever view was from Skye (Arisaig rather). Perfect. Light pollution nil. Couldn't see my hand in front of me.
200mm Newtonian, OMC140, ETX90, 15x70 Binoculars.
Vega
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Post by Vega »

Apparently North Devon is one of the best spots in the country according to the Phillips Dark Sky Map (light pollution map). As I live in Somerset I hope to pop over there sometime soon.
joe
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Re: Darkest skies

Post by joe »

RebeccaM wrote:Can anyone nominate their favourite spots in the UK for star gazing with minimum light pollution? I am a journalist writing an article for fellow novice astronomers, and I'd like to mention some specific areas where you might get a better look than others. Many thanks.
Rebecca has started a new topic for this thread HERE
200mm Newtonian, OMC140, ETX90, 15x70 Binoculars.
Cliff
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Post by Cliff »

Dear al
I personally would hestiate to tell RebeccaM where my favourite dark sky site is, in case she is a spy. It would be just my luck to suggest somewhere and the next thing someone would floodlight it.
Generally speaking visiting dark sky sites as usually been a compromise for me. A few years back I used to go up on the Pennines to do some Deep Sky observing, car journeys of 0.5 to an hour from here. Travelling further might hace provided better sites but a bit of a bind (particular if it clouded up when you got there.
As someone mentioned Scotland can be pretty good.
I got some nice views from the Northumberland coast a few years back near the Farne Islands. I think the Philips Dark Sky Map is pretty good as someone as already suggested.
Best wishes from the Grumpy Old Codger Cliff
RebeccaM
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Thank you!

Post by RebeccaM »

Hi - many thanks for your responses, I look forward to trying some of them myself! Time to consider a holiday obviously - west London's really not the best place for star gazing...
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