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I cannot remember seeing the Coccon nebula, Gerry, so really cannot help :sad: I guess - as you already know - to make sure you've got the area where the neb is residing, stick a UHC filter on a low power EP, rest the eye and see what comes through. If that doesn't work, up the power just a smidge. It's funny but it can also depend on the night. I mean, this summer, I just wasn't able to see a part of the Veil Nebula, even though I knew I was focused on where it was and had seen and sketched it before. I left it a few days, came back and bingo, there it was in all its glory. I put the experience down to fatigue, transparency and a kind of astronomical blindness :grin:

Edited by Qualia
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The Cocoon Nebula is one of the few targets out there that can be as hard to see as the Horsehead Nebula in Orion. And therein lies the challenge! But there is hope.....

The filter for this (and the HH in Orion) is an H-beta. Very few objects require such, and they do cost a bit - about as much as an OIII or top-end UHC - so you need to balance the need with the cost. I'd suggest you do some research into the Hydrogen - beta and what it is useful for.

Clear Skies - and dark ones for this,

Dave

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Hi Gerry, this is a hard one mate, nice and high up this time of year, I can make out the "collection" of stars within the nebula, but nothing else - but I'm under light polluted skies, I usually try for the easier targets, using the 11" I try to "gauge" the sky using M71 just under the Dumbell nebula - much fainter than the Dumbell, I can just make it out as a "misty" patch - even though its a cluster - I see no granulation here but if its there I can then go for the fainter objects.

Just switching between the 36 and 31mm Aspheric's might not sound much in terms of increased Mag - but this slight jump from around x77 (36mm Aspheric) to x90 (31mm Aspheric) really does make a difference going from the Veil (using an O III filter) at x77 to x90 makes it stand out a lot more, with the light pollution I have it is a real struggle to actually see anything at all - let alone any real detail, the Veil is just an arc of "mist" bending around the eyepiece, stretching over a good 2 FOV, last night I looked at the Crescent Nebula and could just make out a little of the Nebula using the O III and averted vision - but this is sort of my limit - it surprised me a little as there was intermittent high cloud, just looking up in general, I thought that the sky was far from ideal.

Filter choice is a little bit of an individual thing for me, I was switching between the UHC-S and a Castell O III, the UHC-s for me gives a little more of a natural look to things - even though the O III wins hands down on high contrast for the majority of the objects I observe I feel that it darkens the background sky much more at the cost of very high contrast on the actual nebulae themselves, but  the UHC-S gives much more of an "hint" of each object, if you study the surroundings a while, the nebulae are there all be it very faint with much lower contrast - I would imagine that just as I view the Dumbell nebula through the 11" with the O III filter, the thing really does jump out at you - so I would imagine that from a very nice dark site, the fainter stuff I struggle with would give very nice high contrast views, as does the really bright Messier's from my light polluted back garden.

As said some nights are much better than others, just find something on the limit of just being barely visible for you, experiment with different filters - to be honest I can see the majority of objects, but under light polluted skies, they are "FAR" from their best with just "hints" and patches of featureless "mist" with no real definition - but I think the GOTO is invaluable for me under my normal conditions - it gives me the time to actually sweep surrounding areas to find the "edges" of each Nebula - these edges are what help me define very subtle boundaries of being able to actually "see" the object stand out from the background sky.

Paul.

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Great info guys, I have identified a few of my issues with your help. One is the looking at the precise location of the object-which is what I need to do by star hopping ( and why goto is an asset) instead of "sweeping" the area. Another big one is the objects zenith location right now which is forcing me to " fight the scope" into position.

I do have a Hb filter and have seen very faint nebs in Auriga with it, so it does work. My Ultrablock is said to have a lowish transmission and also cuts out a bit of Hb, so it may be hindering a bit, not sure.

From home last night in 19.7 mag skies the Veil was good ,the Wisp just visible and surprisingly the Bubble could be just made out over by the Scorpion.

Back to the star charts.....and the RACI

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I have not so far seen this Gerry. Though I had attempted to a couple of times, whilst observing last night, I pretty much kept to more dependable objects using only the O-III filter and enjoying some excellent views of the Crescent, Veil, M17 and picked up the Pelican, in addition to some of the varied planetary nebula. I think as mentioned it is very well positioned at the moment but the sky conditions have to be just right. I refrained from switching to my H-beta filter as condensation later on started to get the better of things. Certainly one to keep in mind and still some time left this season to keep trying. 

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Hello,

I actually find a simple Orion UHC (ultrablock) filter more helpful then H beta on objects like the Cocoon and Horsehead.

The Cocoon is easier to see then the Horsehead, but much, much harder then the Veil. It requires superb sky conditions, and using low powers.  I saw it a month ago with 250mm newt and 31mm aspheric eyepiece under really dark skies. But last weekend could not resolve it from the same location, due to lower sky transparancy

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Last time I tried, which is ages ago, I remember seeing the patch of absent stars where the dust lanes converge around the Cocoon but not seeing the nebulosity itself. I was surprized by this since it never seems photographically particularly faint. I must have another go.

Olly

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Hello,

I actually find a simple Orion UHC (ultrablock) filter more helpful then H beta on objects like the Cocoon and Horsehead.

The Cocoon is easier to see then the Horsehead, but much, much harder then the Veil. It requires superb sky conditions, and using low powers.  I saw it a month ago with 250mm newt and 31mm aspheric eyepiece under really dark skies. But last weekend could not resolve it from the same location, due to lower sky transparancy

I also have an Ultrablock but havn't had much luck with it in general and on this object as well- I may have got a poor example. The UHC's would most likely work better for sure. I am surprised at how faint the Cocoon is.

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