Nebula Filter, which one?

[JOC]

Dave in Vermont I must admit that it is the price of these 'little hunks of glass' which puts me off at the moment.  I wonder what they actually cost to make?  I know that they are precision gratings and all machined etc. but when they start coming at more than the cost of spectacle lenses and stuff like that they start to seem 'off-puttingly' pricey.

[kilix]

JOC you seem to be on the same path at the same time as I am. I am glad for all the topics you started here.

I am a green observer from november 2016. I found out, that advices on all the astronomy forums agree, that filters are a typical example of 'you get what you pay for'. There is no good investment, 50€ UHC or OIII filters are not very good. Only thing those cheaper filters are good at, is that they make you wish you paid for 120€ filter in the first place and did not bother with cheaper ones.

At least thats what I've read.

So after hours of research and reading numerous articles on the subject, I went ahead and purchased Astronomik UHC. At 120€, its a big investment for a small piece of glass. But I figured, that If I am not happy with it, I can sell it for 70% of its purchase price, filters tend to keep their price in second-hand market pretty well.

I was surprised, that it looks like a piece of mirror. I used it twice since, but it was by no means a WOW moment. The nebulae are better pronounced, the background is pitch black, M42's "wings" are more apparent than without the filter, but it didn't make my heart jump. Crab nebula was almost invisible without the filter, but with UHC, you can see something going on. I have to spend more time on the eyepiece with Crab Nebula.

Additionaly, with the UHC filter I noticed, that when your focus is not exactly spot on, the filter makes the light from the stars seem like RGB spots, not unlike on a LCD display. When perfect focus is achieved, RGB spots merge to create one white spot of light. So it kinda helps with focusing. I wonder if this is normal behaviour?

[alanjgreen]

Kilix,

you bought the best with the astronomik UHC,don't worry about that!

you are correct about the red/green dots that help with focusing. The astronomik O3 is similar. Not sure if I get the same effect from Hb (I use it less and memories seem to merge into one as I get older). And yes, they do help with focusing which is useful for sure.

as to the "wow", then that depends on the object and the site/conditions. For a wow, you need something to be much more than without. As M42 is good without a filter, it can only get a degree or two better with a filter.

M1 is never wow visually.

UHC objects where I have had a wow are:

M17 swan nebula - seeing that now looks nothing like the unfiltered, it is huge and so much more gas

M8 lagoon - again so much more there with a filter

veil nebula - I find astronomik UHC does help here (less so than O3) but still a wow

M27 dumbbell - so much more than a dumbbell, it's not easy to pick out the dumbbell as it's lost in the rest of it

You have the right filter, just need to keep moving through the objects as they come around.

Alan

ps. Don't forget the astronomik coatings are guaranteed for 10 years and are supposed to be hard to damage.

[John]

These filters are not "magic bullets" from my experience. The exeception to that are good examples of the O-III type which have for me made the difference between seeing a nice view of an object such as the Veil Nebula and seeing either nothing at all or seeing very faint indications of the object.

I think David Knisely's oft linked to guide is useful as an indication of what effect filter types have on a range of object types and is worth a read before making a selection.

 

[JOC]

kilix it's nice to have other folks around who are at a similar stage to myself. 

Reading this thread - I love folks who post useful threads don't you - this one wasn't mine.  I don't think I'm going to concern myself with a nebula specific filter atm.  From what I see I have a lot to learn regarding just finding my way around the sky and at present I am enjoying the various stars and am holding onto the hope that I can have a good look at the major planets later on this year (Currently I am an 'in the evening not the middle of the night and not waking up ultra early observer').  From the classifieds I have picked up a 2 part polarising filter.  I've got a long term photography background (enthusiastic amateur - lots of record shots and I try for the 'artistic' or special nature shots, but they rarely come off) and I've always had a polarising filter, esp. for the summer for my camera so those I understood and could see the possible benefit of for bright things like Venus and the moon.  I also think that quality wise a polariser seems to be a polariser regardless of what you pay - that seemed to be the case in photography as its only a couple of diffraction gratings.  It makes a positive difference on Venus, but the moon has not been up conveniently since I've had it to see what it will do there.