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What I meant was that we are all trying to manage the expectations of aser hisham, without discouraging him / her, but also being a little cautious over what will actually be seen visually  :smiley:

At least the 6" aperture of the new scope will be an improvement over the 3" scope that was previously being used.

 

 

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11 minutes ago, John said:

What I meant was that we are all trying to manage the expectations of aser hisham, without discouraging him / her, but also being a little cautious over what will actually be seen visually  :smiley:

At least the 6" aperture of the new scope will be an improvement over the 3" scope that was previously being used.

 

 

No issues with any of your comments John. I don't agree with comments that the NAN and Rosette etc are not visible, that was my main point. Apologies if I was confusing in my reply.

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15 minutes ago, ollypenrice said:

I've seen the Rosette easily in a 70mm TeleVue Pronto and even more easily in a 4 inch Genesis. It's a large object so you need a very low magnification and a filter, either UHC or OIII. But what you also need is a dark site and without that you have no chance. At higher powers you can start in the cluster (NGC2244) and move outwards. As you pass through the nebulosity it is easily seen as a milky greyness.

The North America is possible naked eye or in binoculars but, again, you need a very low power and wide field in even a small scope. Dark site remains the answer.

Many Ha-dominated emission nebulae also emit fairly strongly in OIII and this is where our eyes are working well.

Olly

Not saying you can't see them..just can't see them the same as a camera picks up the signal.. through a ep you don't pick up the full shape and size...and  not in its red colour

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2 hours ago, newbie alert said:

rosette is going to look like a bunch of stars..North American isn't going to look like there's anything there

This implies that you cannot see anything, which is not accurate.

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9 minutes ago, Stu said:

No issues with any of your comments John. I don't agree with comments that the NAN and Rosette etc are not visible, that was my main point. Apologies if I was confusing in my reply.

Maybe I should rephrase..not visable in the same way and from my location rosette or north American neb isn't visable.. maybe from a dark sky location they are with filters as olly has pointed out..my location isn't too bad as I can visually see the milky way..but I can't see  north American,rosette,California  etc visually

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2 minutes ago, newbie alert said:

Maybe I should rephrase..not visable in the same way and from my location rosette or north American neb isn't visable.. maybe from a dark sky location they are with filters as olly has pointed out..my location isn't too bad as I can visually see the milky way..but I can't see  north American,rosette,California  etc visually

Clarifying what you say is important. Just saying things are invisible is not that helpful (or accurate). For instance I cannot see the Milky Way from my house, but can just about see the Eastern Veil using an OIII filter. Do you use a UHC or OIII filter at all.

The importance of a dark sky does come through in all this, Olly has fabulous skies for instance, and the only times I have seen the North American Nebula have been from dark sites, generally with an OIII. The OP will have a lot more success with Deep Sky Objects they are able to get to a dark site.

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1 minute ago, Stu said:

Clarifying what you say is important. Just saying things are invisible is not that helpful (or accurate). For instance I cannot see the Milky Way from my house, but can just about see the Eastern Veil using an OIII filter. Do you use a UHC or OIII filter at all.

The importance of a dark sky does come through in all this, Olly has fabulous skies for instance, and the only times I have seen the North American Nebula have been from dark sites, generally with an OIII. The OP will have a lot more success with Deep Sky Objects they are able to get to a dark site.

Fair enough Stu.. yes olly had amazing skies from his location..and I'm sure from a mountain top on a island in a remote site even more things are visable..but unfortunately for me at my location I have to image it /them in order to see them..The veil as you have mentioned I have seen through a filter at a remote top of a mountain situation..

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Just now, newbie alert said:

Fair enough Stu.. yes olly had amazing skies from his location..and I'm sure from a mountain top on a island in a remote site even more things are visable..but unfortunately for me at my location I have to image it /them in order to see them..The veil as you have mentioned I have seen through a filter at a remote top of a mountain situation..

Yep, regardless of filtering, the better the skies, the better the view. You don't need to go to the top of a mountain to see the Veil. My group went to a dark site recently, only around an hour and a half from the M25 and we found mag 21.3 skies, plenty good enough to get good views, given decent transparency of course.

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1 hour ago, newbie alert said:

Not saying you can't see them..just can't see them the same as a camera picks up the signal.. through a ep you don't pick up the full shape and size...and  not in its red colour

Well no, this is true. 

Astrophotos differ from visual observations in two very important ways. 1) The camera can collect light over time while the eye cannot. For the eye, it's photon in, photon out. The camera can accumulate electrons triggered by photons. 2) The eye loses colour sensitivity in situations of low light. This arises from evolutionary advantage. (Making the most of the eye at night while adapting it primarily for the daytime.) However, the camera is about 30% efficient while shooting through a colour filter, which isn't bad.

But the eye's insensitivity to Ha is not as significant as you suggest. Simply looking through an Ha filter at the countryside confirms this. You can see it very easily. What you may be thinking of is the cutoff point of the visual spectrum filters fitted to standard DSLRs. These do cut off the Ha quite significantly.

Olly

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Thank you all , I am definitely going to download stellarium , also thank you for helping me avoid many problems such as the 3x barlow and the expectations . This is what I love about this page , everyone is really helpful and nice , you really encouraged me . I really hope that one day I will get a good telescope .:happy7:

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I'm going to be more cautious now - I don't know the quality of your scope or eyepieces or the observing conditions you will be viewing under, or your experience. All these things can make a big difference to how objects will appear.

The image I posted assumed a good quality scope with a decent eyepiece under good conditions and an observer of average experience.

If the scope is not good quality, not cooled, not in good collimation, with a low quality eyepiece and under poor conditions the image will be poorer. Reverse these factors and the image can be better.

So many variables, it's impossible to do any more than give very approximate guide to how things might appear, with "might" being an important word !

Jupiter might look like this at around 150x if all the factors above are positive (but only might, not definite):

 

fac98-jupiter.jpg

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2 hours ago, aser hisham said:

well , I'm sure it won't be as good but if it is close that would be good enough . you've been really helpful John , you're a really nice person.

I really do think that John has given superb answers to the questions that you have in mind.

Olly

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7 hours ago, IanL said:

Yes from Kent, not so much from Egypt where the OP is located.

I'm not getting at anyone in particular, but it amazes me how often this is overlooked when giving advice.  Especially with people whom it is obvious that English isn't their first language (not a dig at the OP, whose English is fine for its purpose) as it usually indicates they have much better seeing conditions, never mind latitude :-P

 

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13 hours ago, aser hisham said:

I downloaded stellarium as instructed but with my telescopes capabilities the image felt sort of underwhelming , will it really be like this?

Screenshot (12).png

I notice that you are simulating a 6mm eyepiece and 2x barlow in that screenshot (equivalent to a 3mm eyepiece), which I would consider too high a magnification for the telescope. With your telescope I suspect that your best planetary views will come with a 5mm, perhaps 4mm eyepiece, so you may wish to adjust your planned eyepiece purchases. However, if your 2x barlow is one where you can unscrew the barlow lens cell and attach it directly to the filter threads on the eyepiece then doing this will be around 1.5x instead of 2x and so will give you more chance of achieving a usable magnification. 

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