First filter to buy

[Luna-tic]

If you had a $100, or maybe $200 burning a hole in your astronomy funds pocket, what filter would you purchase FIRST, if you had none? Consider whether it could be used both for visual and AP. Also consider that all owned EP's (so far) are 1.25", but they are used in a 2" diagonal, that will also accept filters.

What's the best bang for the buck? (I assume 1.25"), and if there's no significant difference between 1.25 and 2" filters, will $200 buy more than one 1.25", if so, what are the TWO filters you'd buy first?

While typing all this, I considered that one of my T-adapters for my DSLR has a 1.25" end, the other is whatever size screws directly to the rear cell (for prime focus).

[LightBucket]

Well, for me where I live it was a very good quality Light pollution filter, the Idas version, 2”, makes a big difference to my images.but if you don’t have light pollution then not really sure what to get first..

[John]

As a visual observer only I would go for a UHC filter and an O-III filter to use on nebulae.

 

[Knighty2112]

UHC would be the first to go for in my eyes. I’ve got an Explore Scientific that works very well, but a good quality one from Baader or Astronmic would do just as good perhaps. 

[Luna-tic]

Well, dog my cats (as Huckleberry would say) there's a lot of O-III and UHC filters to choose from. What would you suggest,  O-III at 496 and 501 nM, or O-III at 8.5nM?.. Which is better, the UHC-S 60nM bandpass, or UHC-S L-booster? All I've looked at so far are Baader's offerings.

[Knighty2112]

For purely visual use then the link for UHC filter from Baader;

https://www.firstlightoptics.com/uhc-oiii-visual-filters/baader-uhc-s-filter.html

The Explore Scientific filter I use is this;

https://www.firstlightoptics.com/uhc-oiii-visual-filters/explore-scientific-uhc-nebula-filter-1-25-2-inch.html

[Ben the Ignorant]

Astronomik UHC-E, 65€ for the 1.25", 125€ for the 2". Perfectly tailored light curve, less costly than Baader, german quality.

[John]

Baader O-III's tend to have a narrower band pass than most other O-III's which, personally speaking, I found dimmed things just too much for my taste. The Astronomik O-III is excellent and one that I was very happy with.

My current UHC is the Omega DGM NBP filter which I feel is the best UHC that I've used. The Orion Ultrablock and Telescope Services UHC's (again which I've owned in the past) seemed pretty good at a lower cost than some of the premium ones. Castell is another lower cost brand that seems to get good reports.

Bear in mind that I'm speaking purely as a visual observer here. Imaging I think places slightly different demands on filters.

[Ricochet]

If you want to use an OIII filter for both visual and photographic use then you probably want to look at the Astronomik 12nm OII-CCD filter, which I believe is the same as their visual OIII filter with additional UV/IR cut coatings which I think you will need if your DSLR has been/will be astro-modified. Of course, the additional coatings are reflected in the price and so you may find it is just as economical to buy a 2" visual filter and 1.25" imaging filter as it is to buy a 2" imaging filter that you can also use for visual.

[DavidJM]

7 hours ago, John said:

Baader O-III's tend to have a narrower band pass than most other O-III's which, personally speaking, I found dimmed things just too much for my taste. The Astronomik O-III is excellent and one that I was very happy with.

My current UHC is the Omega DGM NBP filter which I feel is the best UHC that I've used. The Orion Ultrablock and Telescope Services UHC's (again which I've owned in the past) seemed pretty good at a lower cost than some of the premium ones. Castell is another lower cost brand that seems to get good reports.

Bear in mind that I'm speaking purely as a visual observer here. Imaging I think places slightly different demands on filters.

Hi John, I'm purely visual too and although I live in Cornwall I'm blighted by a streetlight for quick sessions but in terms of suburbs it's still good, so bearing in mind I'm not far from pretty good dark skies and I wish to view some nebulae would you suggest the Astronomik O-III? Also fund restricted

[John]

If funds are tight then I'd suggest looking into the Explore Scientific filters (O-III or UHC). They seem to offer good value.

[domstar]

Hi could I just jump in and ask if OIII filters are still useful in something as small as a 4 inch or would that put a UHC far ahead?

[Stu]

18 minutes ago, domstar said:

Hi could I just jump in and ask if OIII filters are still useful in something as small as a 4 inch or would that put a UHC far ahead?

I still find an OIII useful in a 4" scope, but it is not a magic bullet. If anything, dark adaptation is more important as the light levels are reduced, but with your eyes properly adjusted, shielded from stray light, and dark skies above, they give great results still.

[Knighty2112]

I used my Explore Scientific UHC filter in my C8 SCT on the dumbbell nebula about two weeks ago and it was almost like looking at it in 3D! And that was from suburban light polluted skies too!

[Stu]

33 minutes ago, John said:

If funds are tight then I'd suggest looking into the Explore Scientific filters (O-III or UHC). They seem to offer good value.

I agree with this, I've had both and in terms of price/performance they are excellent.

[DavidJM]

3 minutes ago, Stu said:

I agree with this, I've had both and in terms of price/performance they are excellent.

Great, with you & John's recommendations, now on my wants list

[John]

1 hour ago, domstar said:

Hi could I just jump in and ask if OIII filters are still useful in something as small as a 4 inch or would that put a UHC far ahead?

I use my O-III regularly my 4" refractors.

The UHC is also good but on the objects which benefit from an O-III, really show a marked difference - often the difference between seeing virtually nothing and having a nice view of an object, even with smaller aperture scopes. The UHC difference is more subtle than this.

 

 

[Dave In Vermont]

The only difference between the Astronomik OIII Visual model and the CCD model of their OIII is the inclusion of a blocker for the UV band. So if you have the Astronomik OIII Vis. model and then decide to do some imaging, all that's needed is to piggyback a stand-alone UV-blocking filter on the OIII Vis. - or anywhere in the optical-pathway.

It should be noted that the Astronomik OIII CCD-model is also just fine for visual usage. Not sure what, or if, there's much of a price difference between the two models. Oh yes - I also concur that the Astronomik OIII is the best of the OIII-filters, producing a more detailed and brighter view than it's Baader counterpart.

Dave

[Luna-tic]

This is all great info, and thanks. I'm going to let the cash smoulder a bit while I continue to look at all these new options. I don't mind spending what's necessary for good quality, or for what I really should have. I just hate having to duplicate stuff because I didn't think it through, or could have gotten one thing that would work a couple of ways.

[ollypenrice]

Some emission targets are large (the Cygnus Loop, the Rosette, etc etc) so, if you have a widefield 2 inch EP, it would be well worth having the 2 inch version.

Olly

[TareqPhoto]

I read somewhere else that as long those filters are nice for visual, they aren't good for imaging, just to consider it, i already have 2 cheap filters of OIII and UHC, i couldn't find them as good for my scope for visual yet, unless i wasn't choosing good targets or good nights, but i tried to use them for imaging and they failed me, well, maybe for first time, didn't give them second chances to test, maybe later, but i already happy with Ha filter that will keep me busy for long long time.