Have I made a mistake with the Olll

[alan potts]

While in England on a spending spree I picked up an Astronomik 2 inch visual filter for Olll. I had read many of the threads by members and thought I would give it a try and with this being a secondhand pick-up I was never going to a great deal out of pocket if thing went pear shaped.

Now I know that these filters like aperture but I was giving it a try in my 190mm M/N which lets face it is almost 8 inches. Now this night there was a 5 day moon in the sky but I thought It would see something as the Moon was a fair distance away ( this was last month). I set the goto which had been working OK as I recall to the veil nebula and there was nothing there at all.

Now I believe my 12 inch is too smaller FOV to see the veil in one piece but can it be seen with smaller instruments or did I make a mistake trying when the Moon was on the menu?

Any help would be great

Alan

[John]

The moon would not help at all Alan. As you know I have an Astronomik O-III and I find it will show me both the E & W Veil really quite clearly with my 4" refractor and I've even managed to pick up Pickerings wisp on really dark nights.

To be honest I don't bother much with DSO observing when the moon is in the sky - even those you can see are far from their best. Maybe open and globular clusters but certainly nothing nebulous or galactic.

It's surprising how the moonlight in the sky seems to percolate even well away from where the moon is actually positioned.

[Rustysplit]

The moon does wash it out quite a lot. How far away was the moon? I am sure you 190 is more than enough to see it under reasonable skies. On a dark night from home I see the veil very clearly, even with lp when using the 0III (orion). With the moon in play, it just vanishes, or very nearly.

[rwilkey]

Hi Alan, I agree with the others, I also use it (Lumicon or a SW) on my 4" frac and its just hopeless with any type of Moon.

[alan potts]

Looks like it is me being rather green without the black, still, I have never used one ever before so I guess it is a mistake that can be forgiven. I will have a try with it later in the week when the Moon gets up later, I still have a good deal of time before the the veil as a target disappears.

I have been busy the last few clear nights getting some notes together on the 3mm Radian and 3.5mm Delos, as the Moon was one of the prime targets, I have also had some surprises with these two eyepieces, a real shock to me, which I will report on of course. It is really nice when you try something expecting nothing but failure and then getting a stunning result, quite the opposite to the filter.

Thanks John, Alan and Robin.

Ala

[John]

..... I have also had some surprises with these two eyepieces, a real shock to me, which I will report on of course. ...

You tease Alan ..... ! 

[YKSE]

Looks like it is me being rather green without the black, still, I have never used one ever before so I guess it is a mistake that can be forgiven. I will have a try with it later in the week when the Moon gets up later, I still have a good deal of time before the the veil as a target disappears.

Agree with others. I could pick up the veil in my backyard in 130P with 1.25"TS OIII, when the moon was not there.

I have been busy the last few clear nights getting some notes together on the 3mm Radian and 3.5mm Delos, as the Moon was one of the prime targets, I have also had some surprises with these two eyepieces, a real shock to me, which I will report on of course. It is really nice when you try something expecting nothing but failure and then getting a stunning result, quite the opposite to the filter.

Thanks John, Alan and Robin.

Seems that we can look forward to a new hot review

[Reeny]

I was left a little bit deflated when I tried the OIII for the very first time.

I already knew how the filter works - by blocking out a very large percentage of the light.

But I wasn't prepared for the deep dark blackout.

The views made more sense once I got my head around it on the 2nd time of use.

By the 3rd time, I will be ready for the faint, clear, non-blurry image to appear out of the darkness.

I haven't used the filter while the moon is out.

But I expect the moon shine would make your adjustment to the filter much more difficult.

[bingevader]

Ala

...be praised!

But you're the oracle!?

I'm not sure I'll ever recover from this.

But if you need a hand using the filter, I'm sure we can all make it to your star party.

Cheers

[Rustysplit]

You tease Alan ..... ! 

I'll second that!  C'mon Alan, spill the beans....

[LDW1]

The moon would not help at all Alan. As you know I have an Astronomik O-III and I find it will show me both the E & W Veil really quite clearly with my 4" refractor and I've even managed to pick up Pickerings wisp on really dark nights.

To be honest I don't bother much with DSO observing when the moon is in the sky - even those you can see are far from their best. Maybe open and globular clusters but certainly nothing nebulous or galactic.

It's surprising how the moonlight in the sky seems to percolate even well away from where the moon is actually positioned.

I think it's a complete waste of time when the moon is bright unless maybe it's the Orion, Lagoon and a couple more and even they wash out !! If you try and observe these DSO's as well as Galaxies you will lose complete faith in these filters which should not be the case !!

[LDW1]

I think it's a complete waste of time when the moon is bright unless maybe it's the Orion, Lagoon and a couple more and even they wash out !! If you try and observe these DSO's as well as Galaxies you will lose complete faith in these filters which should not be the case !!

Maybe in your case you live too close to the moon !? LOL - eh !!

[John]

I think it's a complete waste of time when the moon is bright unless maybe it's the Orion, Lagoon and a couple more and even they wash out !! If you try and observe these DSO's as well as Galaxies you will lose complete faith in these filters which should not be the case !!

So true !

It's just so easy to blame poor results on our equipment when the viewing conditions can play a much larger part in determining what we can actually see on any particular occasion 

[Joves]

Hi Alan,

If it's any consolation, I haven't had any luck with the Veil with either of my scopes OR filters... And I've tried them all. I'd say this is definitely due to conditions more than anything else.

I've found that the OIII filter definitely does work better on specific targets, particularly the brighter ones (Tarantula Nebula, for example) as it certainly does darken the overall FOV. Hence why I use the UHC a lot more often, as more of a general LP filter. The OIII is a brilliant filter though. Given the right target and sky conditions, I have no doubt your current worries of having made a mistake will be all but eradicated!

Aaron

[alan potts]

Yes you lot I do like to tease, one has to make this as interesing as one can. When your using such magnification your a bit limited to your targets or so I thought.

I pointed the 115mm at a tight globular cluster M15, largely after reading something Swampthing had writen, "Globulars respond well to magnification", well I though we will see. Now I would never have thought a 4 1/2 inch refractor of any kind would have opened up this cluster. It was with the 3mm Radian at first giving about X262 which I would have thought was nuts. However you could see the outer stars freeing themselves from the main bundle, not easily but they were there. This was made all the more remarkable in view of the fact there was a 4 day old moon in the sky which for sure would not help matters and it was not totally dark.

I want to recheck my findings and enlarge on the clusters in the next couple of weeks before I put the full report together but this seems to surgest to me that all is not lost if the street lights are spoiling things, though whether Moon light and street light have the same effect I don't know.

So thanks go out to Swampthing!

Alan

BTW 'Ala' was a mistake made but me having an injured hand, hope I did not offend anyone, if I did sorry.

[swamp thing]

Hi Alan,If it's any consolation, I haven't had any luck with the Veil with either of my scopes OR filters... And I've tried them all.

Is it close to your horizon from Sydney? If so a trip into the countryside may prove fruitful.

With an O-III filter and dark skies you can't fail to see the veil neb.

[Joves]

Hi Steve,

From where I observe, at the few times I've tried for the Veil (and it really has only been 2 or 3 times) it's definitely not positioned great in the sky. Quite close to the horizon, yes, you're right. I'm sure when I'm next under dark skies, away from the Sydney LP and without an almost full moon, I shouldn't have too much of a problem.

Is the OIII the filter of choice for the Veil, in particular?

Cheers,

Aaron

[swamp thing]

Aaron the O-III is way better on the veil nebula.

It's often said "O-III on objects you can't see, UHC on ones you can"

This is because of exit pupils. Line filters block more light, therefore work best with bigger exit pupils. If we "over power" our line filter (use too higher power) the view will quickly dim. Most objects we can't see are big low surface brightness objects (the veil, rosette, NA neb etc), we use low power here and the O-III rocks.

Objects we can see, we ramp power up to frame them nicely. O-III doesn't like higher power and shows us as much with very dim views.

Keep your exit pupils big and your O-III will give you happy observing

[John]

My first views of the Veil came with a rather tame Baader UHC-S filter used with a 100mm refractor. I then switched to a "fiercer" UHC in the Orion Ultrablock and the contrast got a bit better with the same aperture. When I moved to the Astronomik O-III the Veil group of objects (as I think of them) really started to jump out.

With my 12" scope on a dark moonless night and the 20mm 100 degree ES eyepiece (1.26 true degree view) I can pan around the Veil complex examining one segment after another and the views are really starting to look photographic with fine filamentary structure and long sweeping arcs of nebulosity seeming to drape themselves amongst the stars. It's a totally stunning object for me, one of my favourites in the whole hobby and frankly worth the pricey filter and the ultrawide 2" eyepieces on it's own

I don't get a lot of kicks from DSO's to be honest mainly because my garden is not that well placed for them but the Veil is an exception and I can't get enough of it though any of my scopes 

[Naemeth]

I don't think you've made a mistake, Alan. Just try the Veil on the night of a new Moon .

[Joves]

Aaron the O-III is way better on the veil nebula.

It's often said "O-III on objects you can't see, UHC on ones you can"

This is because of exit pupils. Line filters block more light, therefore work best with bigger exit pupils. If we "over power" our line filter (use too higher power) the view will quickly dim. Most objects we can't see are big low surface brightness objects (the veil, rosette, NA neb etc), we use low power here and the O-III rocks.

Objects we can see, we ramp power up to frame them nicely. O-III doesn't like higher power and shows us as much with very dim views.

Keep your exit pupils big and your O-III will give you happy observing

Great explanation, thanks Steve. Makes a lot of sense and will be kept in mind as a handy rule of thumb when using my filters from now on. Thanks mate!

[Mark at Beaufort]

Hello Alan hope you are well - I do like the reviews you produce so keep up the good work.

A few years ago I bought a Skywatcher O-lll filter and was very disappointed with the results. In the end I sold it and went back to using a UHC filter which gave me good views including the Veil. Just recently I thought about buying a O-lll again and obtained a TS 1.25" O-lll from A.B & S which has given me a different opinion on this type of filter. (I didn't consider buying a 2" filter at this stage just in case I was disappointed again). I am able to screw this 1.25" filter into a 2" adapter so I can use my 21mm Ethos. I have had some nice views of the Veil recently using both my 6" Newt and 10" Dob - so I am now happy about using the O-lll filter and might purchase the 2" variety in the future.

I don't bother looking for faint DSOs when the Moon is bright. I bought a 180mm Mak/Cass earlier this year so that I can view the Planets and the Lunar surface with binoviewers. My 4" APO frac is mainly used when the Moon is out to view double stars.

Alan I know you live in a dark site so I would imagine that with the Moon out of the way you views with the Astronomik are going to be great.

[alan potts]

Many thanks to all for the good advice, it was not a target that I knew very much about, so I will take all on board and give it a try later in the week.

Mark, good to hear from you again.

Thanks for the kind words, I try my best and do a great deal of observing to get the basis for them. I do get a great deal of clear sky so why not make the most of it and hopefully get a better and more accurate report. It has now come down to almost having to buy eyepieces to write about them though I could always just do a report on a given focal length in many scopes, I may have to do this to use the 21mm Ethos, I just can't put the 20mm Nagler down, lord knows why.

BTW I got the convertor for the Mak to SC thread and will try it soon, the scope is outside all the time now but as I am using the 3mm and 3.5mm it is not one that even gets looked at, I guess X900 is a bit high for even a good scope and a dam good eyepiece, might try it though now I have typed this.

Take care and clear skies,

Alan.

[Mike73]

A few years ago I bought a Skywatcher O-lll filter and was very disappointed with the results. In the end I sold it and went back to using a UHC filter which gave me good views including the Veil. Just recently I thought about buying a O-lll again and obtained a TS 1.25" O-lll from A.B & S which has given me a different opinion on this type of filter. (I didn't consider buying a 2" filter at this stage just in case I was disappointed again). I am able to screw this 1.25" filter into a 2" adapter so I can use my 21mm Ethos. I have had some nice views of the Veil recently using both my 6" Newt and 10" Dob - so I am now happy about using the O-lll filter and might purchase the 2" variety in the future.

Mark like you I'm currently using a TS OIII filter which I've been very happy with mainly because I do like to see 'some' of the star field.

In the past I've owned both a Lumicon OIII and Astronomik UHC, I found the OIII way too strong for most objects and as Swamp Thing rightly pointed increasing the magnification and decreasing the exit pupil size only made the views dimmer so that filter was left in the bag most of the time.

The first time I used the TS OIII I quickly realised just how similar the views were to my Astronomik UHC, I haven't really thought too much about this until I read your post so I started digging about for more info on each filter and attached the filter curves below, pretty interesting I think!

Alan apologies for taking your thread a little off topic.

[alan potts]

Mike,

I do not consider adding more information to a thread taking it off topic, though I am not sure I really understand the graphs but they look the business.

When ever I see you post I always wonder about the 18 inch Sumerian I so nearly ordered, it would have only meant a few less eyepieces and a 180 Mak scope.

Clear skies,

Alan.