Nebula Filters

[John]

8 minutes ago, Andy1978 said:

A tad off piste but I'm hunting a 30mm~ EP for DSO viewing.  My question is would an ES 32mm 82° work well with a 200mm Dob?.  I would hope this coupled with the OIII would lead to some pleasant nebula viewing.

The ES 30 82 is a great eyepiece. It's very heavy (as are others of similar spec) so be prepared to add some counter weighting to the bottom end of your scope. O-III filters work great at medium powers as well as low ones as well  

[Andy1978]

28 minutes ago, John said:

The ES 30 82 is a great eyepiece. It's very heavy (as are others of similar spec) so be prepared to add some counter weighting to the bottom end of your scope. O-III filters work great at medium powers as well as low ones as well  

Thanks John, do you think a f5.9 scope would be fine to use with this EP?.  Also, would the tension control handles on a dobsonian base help counter the extra 2.3lb?

[John]

22 minutes ago, Andy1978 said:

Thanks John, do you think a f5.9 scope would be fine to use with this EP?.  Also, would the tension control handles on a dobsonian base help counter the extra 2.3lb?

The eyepiece will be fine at F/5.9 - it's practially as well corrected as the Nagler 31 which is good down to F/4ish. The tension control handles will probably be enough when viewing objects reasonably high in the sky but you might get some "nose droop" when viewing objects at lower levels. With the Skywatcher dobs using a steel tube (I think) some folks use a heavy magnet on the bottom part of the tube as required.

[Andy1978]

16 minutes ago, John said:

The eyepiece will be fine at F/5.9 - it's practially as well corrected as the Nagler 31 which is good down to F/4ish. The tension control handles will probably be enough when viewing objects reasonably high in the sky but you might get some "nose droop" when viewing objects at lower levels. With the Skywatcher dobs using a steel tube (I think) some folks use a heavy magnet on the bottom part of the tube as required.

Aha that'll work, I think I'll get the ES 30mm along with a large magnet or 2.  Thank you I appreciate you sharing your knowledge.

[cletrac1922]

Andy

Attached link gives a good description of different filters, and to use what for planetary and nebula viewing

John 

[rwilkey]

22 hours ago, Andy1978 said:

Thank you all for your responses, I value each of them.

I have this morning ordered a Astronomik 2" OIII filter, Rother Valley Optics currently has them at the best price.  Accordingly I won't end up buying another OIII filter so this should save me money in the long term, and I'll  be hopefully spoilt in my nearby countryside  dark skies with some fantastic nebula views

I'll add the Astronomik UHC filter to my collection on another pay day, and also perhaps the Baader Neodymium moon and sky glow filter too but that requires further research.

Best regards

Andy

Hi Andy, well done for making a great decision.  One thing about the Astronomik (like the Lumicon, which I have) is that they are better engineered, which is one of the defining differences in these filters, not necessarily whether the glass is better than any other, which the untrained eye might find difficult to detect.  The 2" is a good choice, I only have 2", which you can freely use with 1.25" ep's as you can place the filter on the 1.25" adaptor, or anywhere else in the optical chain and it does the job perfectly.  The ES82 30mm is also a great choice, gives superb views of the sky even at f/5.