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Rosette nebula


neil groves

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The cluster within the Rosette is NGC 2244 and is very easy to see, even with the naked eye under good conditions.

i have never managed to see it myself, but with binoculars the nebula is visible if observed under very dark skies. I guess all the usual rules about well adapted night vision apply, perhaps get your bino's on a tripod, get a chair and study the area for a decent period of time.

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Can anyone advise me if the rosette nebula is visible through binoculars or a 120 ED telescope, or is it a photographic subject only? Neil.

Photographic :D :D Err no. The rosette is so big it is visible to the naked eye if the site is dark enough. Using an O-III filter head against your naked eye will reveal this object.

It certainly does not require any sort of aperture at all and makes a superb binocular target.

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I saw this object through bins at the Winter Star Party (Florida Keys) in 2001. The bins were huge,  40 x 120 or something like that. Each eyepiece had its own filter attached (not sure what type of filter, probably OIII). It was a jaw dropping sight. Apart from the colour it looked just like a photograph.  I doubt that you *need* huge bins, but if you really want to go for it, I think a dark site is your first priority.

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Can anyone advise me if the rosette nebula is visible through binoculars or a 120 ED telescope, or is it a photographic subject only?

Neil.

Neil I can see this object well with my 120ED, dark skies mean a lot. Also the exit pupil of the EP must match the filter. My 23mm,25mm EP's show it ok, but my 30mm,32mm show it better.

Do you have a 30mm-40mm EP and OIII to try on this object?

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Neil I can see this object well with my 120ED, dark skies mean a lot. Also the exit pupil of the EP must match the filter. My 23mm,25mm EP's show it ok, but my 30mm,32mm show it better.

Do you have a 30mm-40mm EP and OIII to try on this object?

Nice! I am going to try with my 24 Pan, which on my scope has a 4 mm exit pupil like your 30mm on your 120ED! 

Looking forward to giving a try! Com'on clouds! Go away!  :rolleyes:

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I have a 32mm wide field eye piece (68°) but no filters.

If you want to view emission nebula Neil either a UHC or OIII is pretty much needed and my preference is the OIII. The 120ED shows the Veil, NA neb, Monkeyhead, Rosette and piles more and going down in mag towards a 40mm EP would help too. I see all the objects listed with my 30mm ES 82/OIII and the 120mm.

Some OIII's are more fussy to the exit pupil than others IMHO, a little broader bandpass isn't a bad thing if EP selection is limited.

Try to get to as dark of sky as possible and time the object so its near the zenith.

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Nice! I am going to try with my 24 Pan, which on my scope has a 4 mm exit pupil like your 30mm on your 120ED! 

Looking forward to giving a try! Com'on clouds! Go away!  :rolleyes:

Hi pdp, your Astronomik OIII is perfect to see these objects and the 4mm exit will work well with this filter, from dark, transparent skies you will see the Rosette, keeping in mind that it is huge and as always "catching an edge" is a great way to start.

Waiting for the report!

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The better the conditions the bigger nebs get in the EP, my 21mm EP with a 1.7 deg TFOV does a good job on the Rosette, but the 30mm ES does a better one with a 2 deg TFOV. Ideally you want to be able to frame it. A lot of times there are detached patches just off some of these big nebs and a large TFOV can help see them.

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Hi pdp, your Astronomik OIII is perfect to see these objects and the 4mm exit will work well with this filter, from dark, transparent skies you will see the Rosette, keeping in mind that it is huge and as always "catching an edge" is a great way to start.

Waiting for the report!

Yup!  :icon_salut:  I am really curious to see it! As you said, it should be a good combination!  :angel10:  

Slightly off topic..  I haven't had time to use the OIII as it arrived only last week, but I used the UHC a few times. On average sky (stars up to 4-4.5 mag), I noticed that the view was much better using a Plossl 20 (exit pupil 3.3mm) rather than a Pan 24 (exit pupil 4.0mm).

Although it is quite obvious that a view at 3.3mm e.p. shows a bit more contrast than one at 4.0mm e.p., I expected that the UHC reduced the sky brightness much more and therefore that at 3.3mm e.p the image started being too dim when using the UHC. 

Do you think this is due to the less glass in the plossl compared to the Panoptic, OR that on average skies a shorter exit pupil "simulates" a darker sky and this improves the work of the filter uhc?

I guess it also depends on the target.. On a bright object such as m42, this effect is really clear.. 

p.s.

rosette -> next target (pan24+OIII) :-) Many thanks!

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I just got back from a dark site trip that turned out pretty bad :Envy: -32c and forecast good transparency  lol!! I watched the stars disappear before my eyes and I couldn't even split polaris... so much for the forecast :rolleyes:

So the point is that the sky means a lot with how things work, good observation about the lower exit pupil giving more contrast under lighter, poorer skies- I notice this too. From LP skies I always lower the exit and the UHC is forgiving is this respect.

You may come to notice that 2 EP's of identical focal length give different levels of contrast, with and without a filter- I do. So yes, different FL eyepieces may have different levels of contrast as well. It is a common thought that "less glass" is better, but this can be wrong, very wrong- it is totally dependent on which EP's you're comparing. For example my 10mm Ethos, with piles of glass in it, is my best galaxy EP so far, well matched to my scope. The Ethos has great glass and coatings matched to the index of the glass, making these EP's more than a match for some simpler design EP's.

A simple design EP, especially orthos, that are made the best the can be ie Zeiss ZAOII, can best the more complex designs ( and everything else). In your case I don't doubt your 20mm plossl bests the 24 Pan on some things, TV plossl's are very good.

What were you looking at when you noticed that " bit more contrast", point source object or an extended one? I bring this up as you have grasped the exit pupil idea well.

Have you heard of extended objects? and the fact that the sky and the object both dim as you reduce the exit pupil? keeping the contrast the same? If your interested maybe start a thread on this super important subject.

You are way ahead of the game pdp! keep on pursuing!

Gerry

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Neil, It's a little over 2moon diameters across. You want good transparency, not just dark skies. Have a test nebula.... If it's easy then you have a chance of faint stuff, otherwise not. I was pleasantly surprised by catching glimpses of nebulae from home a week or so back, not expecting that.

PeterW

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Photographic :D :D Err no. The rosette is so big it is visible to the naked eye if the site is dark enough. Using an O-III filter head against your naked eye will reveal this object.

It certainly does not require any sort of aperture at all and makes a superb binocular target.

Cool!  I;ve obviously just never tried to observe it from a dark enough site :)

Will give it a go next time I'm at a dark sky site.  Cheers!

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I just got back from a dark site trip that turned out pretty bad :Envy: -32c and forecast good transparency  lol!! I watched the stars disappear before my eyes and I couldn't even split polaris... so much for the forecast :rolleyes:

So the point is that the sky means a lot with how things work, good observation about the lower exit pupil giving more contrast under lighter, poorer skies- I notice this too. From LP skies I always lower the exit and the UHC is forgiving is this respect.

You may come to notice that 2 EP's of identical focal length give different levels of contrast, with and without a filter- I do. So yes, different FL eyepieces may have different levels of contrast as well. It is a common thought that "less glass" is better, but this can be wrong, very wrong- it is totally dependent on which EP's you're comparing. For example my 10mm Ethos, with piles of glass in it, is my best galaxy EP so far, well matched to my scope. The Ethos has great glass and coatings matched to the index of the glass, making these EP's more than a match for some simpler design EP's.

A simple design EP, especially orthos, that are made the best the can be ie Zeiss ZAOII, can best the more complex designs ( and everything else). In your case I don't doubt your 20mm plossl bests the 24 Pan on some things, TV plossl's are very good.

What were you looking at when you noticed that " bit more contrast", point source object or an extended one? I bring this up as you have grasped the exit pupil idea well.

Have you heard of extended objects? and the fact that the sky and the object both dim as you reduce the exit pupil? keeping the contrast the same? If your interested maybe start a thread on this super important subject.

You are way ahead of the game pdp! keep on pursuing!

Gerry

Thanks a lot for your explanation Gerry! I found it very useful and it made me think a lot! 

I suspect I was twisted by the object (M42). Although it is an extended object, I suspect the core works more like a point source object. And it is in the latter where I detected this increase in contrast! 

I will start a new thread on this as I am interested and would like to know more about it!  :rolleyes:

Thank you very much again  :smiley:

Piero

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Stu, I love when you put these objects up with your program, and the Telrad circles. Some objects are listed at sizes that aren't that representative IMHO, but your program is very good. The image above shows why my 1.7mm TFOV is marginal on this object and why the 2 deg TFOV is better for me. The Rosette is listed at about 1 deg, but I find this misleading.

Thanks again

Gerry

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I went out in the yard last night and found NGC2244 easily enough, no sign of the nebula though, or maybe I just didn't know what I was looking at, I was probably using a to high power eyepiece thinking about it this morning, I also couldn't find M101 and have searched for it many many times, never ever found that elusive object,

 I was at 52X i'll have another go when I get my 8" Orion Newt.

Neil.

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M101 is a fairly easy binocular object IF you have clear, dark skies. The Rosette is similar, but has the advantage that filters bring out more detail. I once spotted it with my C8, but curiously, I first spotted the dust-lane featured. These are better defined than the edges of the nebula. It is easier in my APM80 with its wide FOV.

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