OIII filter question

[globular]

1 hour ago, Deadlake said:

Why the EDGE over a stock C8. Ability to add fans to cool down or not really an issue?

 

46 minutes ago, Stu said:

Didn’t see any mention of the Edge, but I found my C8 Edge excellent with widefield eyepieces. I think the Edge optics flatten the field and give better stars. Most people think they are only really of benefit for imaging, but they also perform better for observing to my eyes.

The Edge optics do block the baffle tube so if anything they cool slower than a standard SCT. The aftermarket vent fans are potentially needed because of this.

I don't want take this thread too far off topic with a long explanation of my choice of Edge HD over a stock C8, but Stu's answer is part of it re flat field and better stars. Cooling is pretty good in my version too as it's carbon fibre (no fans).
My main belief / delusion that it is a "good one" stems from reading a lot of negative stuff on here, over the year or so I've been here, about lack of sharpness, lack of contrast, slow to cool, etc. etc.  and not recognising a lot of it in my experience with mine.

[tripleped]

ordered the TV bandmate type  2  (1.25 ")   $100 from  OPT  telescopes (free shipping)       can't wait to try it out 

[Deadlake]

6 minutes ago, globular said:

 

I don't want take this thread too far off topic with a long explanation of my choice of Edge HD over a stock C8, but Stu's answer is part of it re flat field and better stars. Cooling is pretty good in my version too as it's carbon fibre (no fans).
My main belief / delusion that it is a "good one" stems from reading a lot of negative stuff on here, over the year or so I've been here, about lack of sharpness, lack of contrast, slow to cool, etc. etc.  and not recognising a lot of it in my experience with mine.

I always like to ask and good to hear positive. There is a religious SCT thread going on CN at the moment around SCT quality control. Either a 9.25 EDGE or 210 Mewlon once the stock sorts itself out to add to the collection in the future…

[jock1958]

Hi @tripleped I’m in Bortle 5/6 skies and was in this very region last week thanks to some inspiration from a fellow SGL’r.
I used my TV bandmate UHC filter, 4” Frac & 31mm TV nagler eyepiece and the nebulas you mentioned really stood out especially the omega (swan). 
When I have a chance will try my Astronomic OIII filter on these targets and do a comparison. 

[tripleped]

That’s good to know! Look forward to your comparison report. 

[jock1958]

2 hours ago, tripleped said:

That’s good to know! Look forward to your comparison report. 

Will do if the South Wales weather cooperates and before they get too low in the sky. 
Forgot to mention David Knisley who posts a lot on the CN forum wrote this excellent review on what filters to use on DSO’s.
https://www.prairieastronomyclub.org/useful-filters-for-viewing-deep-sky-objects/

Edited September 3, 2021 by jock1958

[tripleped]

That’s a tremendously helpful article! Thanks!

[jock1958]

On 03/09/2021 at 13:31, tripleped said:

That’s good to know! Look forward to your comparison report. 

Out last night and can confirm the Astronomik OIII shows the Omega more clearly with sharper detail after swapping it back and forth with my TV UHC, background sky is noticeably darker with the OIII which obviously enhances this type of nebula.
Without a filter it was invisible which is no surprise in my bortle 5 / 6 skies, it’s also getting fairly low now so maybe have to wait until next year to have another crack at it! 

Edited September 7, 2021 by jock1958

[Alan White]

@jock1958 interesting information about an oiii filter and a 4" refractor.
I was pondering an oiii 1.25" in my ED103 for much the same reason as you, but was unsure if it was not too much for a 4".
 

[Stu]

20 minutes ago, Alan White said:

@jock1958 interesting information about an oiii filter and a 4" refractor.
I was pondering an oiii 1.25" in my ED103 for much the same reason as you, but was unsure if it was not too much for a 4".
 

I have used OIII filters in 4” refractors for quite a few years now, and even in smaller 72mm scopes they work well. They don’t change the laws of physics (Jim 🤣), so normal rules apply in terms of getting as dark adapted as possible, shielding from glare and getting under the best skies you can, but they still work and have the benefit of being able to show you a wider field than a larger dob.

With a nice 2” eyepiece (31mm Nag or 35mm Pan say), and 2” filter you will get over 3 degrees of sky, not quite enough for the Veil but still very nice. 

[jock1958]

23 minutes ago, Alan White said:

@jock1958 interesting information about an oiii filter and a 4" refractor.
I was pondering an oiii 1.25" in my ED103 for much the same reason as you, but was unsure if it was not too much for a 4".
 

Yeh I read the astronomik instructions for the OIII and it does say that you require more than 150mm aperture for best results and dark skies. All I can say it definitely works with my 4” Tak and makes the difference of being able to see it or not. 

Edited September 7, 2021 by jock1958

[jetstream]

7 hours ago, jock1958 said:

Out last night and can confirm the Astronomik OIII shows the Omega more clearly with sharper detail

Congrats for a fine session!

Yes, theres a reason we recommend the OIII first.

Under truly dark skies a UHC will bring out more extent of nebulosity on some nebs, but the OIII will make things show when the other wont in lighter skies. Under dark skies the OIII gives a "brighter image" on most objects and with the greatest extent on some like the Veil.

IMHO.

[Rob Aylen]

I used the astronomik 0III for the first time last night and it really does make a big difference. Was using with a 10 dob, Bortle 4.

[russ]

I was using the Orion OIII last night with the Startravel 150 under Bortle 5 skies. Transparency was poor. Without the OIII not even a hint of the Veil. With the OIII all parts of the Veil were not a problem. Not tried with the ED100 as I bought the 150 for this very reason. The OIII also worked incredibly well on the Owl, the downside is I lost the companion galaxy from the view. The OIII is an essential part of my observing setup. One of the first things I re-bought this year.