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As new condition ultra narrowband 1.25" Baader filter. 3.5nm bandpass for nice small stars.
Bought and loved it, but using a DSLR again and have no use for this filter.
£140, can post.
Time for yet another cry for help when it comes to choosing diagonal. I have read the many similar threads and gathered some knowledge (too many to start linking). I have come some way in my process and now that it is coming to final decisions I would like to hear from the experts. Not many of threads I have read end with the OP returning to deliver some review/verdict of his/her final decision. While I wait for response on some thread where I asked about the result, the eagerness in me forces me to write my own thread. Perhaps some of the people asking these questions before can now answer in my thread as experts!
I have the Nexstar Evolution 9.25 and am currently using the stock diagonal. My eyepieces are the Baader 8-24 mm zoom and the stock 40 mm Plössl. I would also like to upgrade EPs and there I'm looking at something better in 24 mm range, as well some nice low power for more FOV. I'm following threads about EPs and SCTs with great interest for this (on CN). Can say that I'm currently leaning towards the 1.25" 24 mm ES 68° and 2" 36 mm Hyperion aspheric (if going 2" route).
I'm thinking 2 alternatives (including a budget alternative for one of them). I'm looking at Baader mainly for ClickLock (and expect good optics):
Baader T2 Zeiss prism with a 1.25" ClickLock EP (T2 part #08) -OR- the 2" prism with 2" ClickLock (splurging that is). The budget alternative would be to get the non-Zeiss T2 prism instead for the 1.25". Worth noting that I would like to get the Celestron f/6.3 Reducer/Corrector. This would be for future purposes of delving into EAA but of course I would use it visually as well (especially if choosing the T2 route). The reasoning for my alternatives:
Go for the 2" Zeiss prism to theoretically get the best of the best in visual terms. I would make better use of the 46 mm baffle tube opening. Theoretically possible to combine with the R/C thanks to relative short light path (although not necessarily needed with 2" EPs). Downside of going to 2" accessories would be the cost, EPs, filters etc., on top of diagonal. Would not be able to spend all these costs at once. Cheaper route with T2 prism (especially the non-Zeiss), not only diagonal but also the other accessories. Cost of the R/C would be comparable to e.g. the 36 mm aspheric and give similar power and FOV with the 24 mm ES, i.e. the 24 mm would act as both. Extra plus is the ClickLock clamp for 1.25" with built in fine focusing not involving the mirror. Downside of knowing that not all light coming out of baffle tube is used. To get the wide FOV (24 mm + R/C) I'm adding glass to the optical train (theoretically not a good thing). I'm leaning towards the T2 as it would be a cheaper diagonal and for EPs I would only need the 24 mm and then the reducer instead of a 30-40 mm, so saving the expense of one EP. Then I would already have the reducer for continuing into EAA. The questions I hope the experts here can help with:
The old reducer vs 2" diagonal question. With R/C and the 24 mm I can get roughly the same mag and FOV as e.g. the 36 mm Hyperion (technically 38 mm vs 36 mm and 68° vs 72°). Also reading good things about the ES 68° and with R/C the EP should behave the same. Am I missing something here? The logics say that the I would lose some contrast with the R/C (not using full opening + adding elements), correct? Possibly flatter fields though (not important now, hopefully the EP threads might tell soon enough). The Zeiss vs non-Zeiss T2? Big differences? I have read a few posts on this so most to get some updated views here (have read that Baader has changed some things over the years). Using the R/C (f/6.3) with these prisms. I know f/7 is mentioned as "the limit" but also remember BillP's test where he was happy down to f/6 with the prisms (in 2014 at least). Perhaps most important: have I missed some other obvious alternative here? Maybe I have forgotten some question here but perhaps for the best as I assume those who have gotten this far are tired of reading now. Thanks for getting here though!
COMPLETED - SOLD****BARGAIN NEW PRICE*ASTRODON Tru-Balance RGB Gen2 E-series filter, 36mm, unmountedBy Nikolas74
Selling my LRGB filters 36mm unmounted , because I decided to use only my Narrowband and to invest in something else that I want.
The filters are placed inside my Atik EFW2 at the moment but I can send photos if someone is really interested , so I don't loose my cc'd setup position.
Are in excellent condition ,sold in their original boxes.
The filters are well known so not much words need to say.
Some info you can find here at Astrodons site:
The retail price is about £800 if I am not mistaken I will sell it for £500..............£375
Other offers can be accepted within reasonable price 😀
Payment via PAYPAL is accepted, buyer pays the fees.
I post them from Athens Greece in A class shipment secured.
I will pay the postage expenses.
This has been my project since the start of this season and now I think I´ll just leave it... for now 😉
I started last season (with a longer FL) but didn´t like how my Baader O3 filter matched the Astrodon Ha filter, so now I had to get a 3nm O3 as well.
This is a total of:
60*5 minutes of 3nm Ha
114*5 minutes of 3nm O3.
Shot with a ZWO ASI1600MM-Cool and a Canon 300/4L IS tele lens. The lens suffers from bad star shapes in the corners but I managed to get it decent anyway. Didn´t want to stop it down from f/4 either.
Combined as a semi-RGB (or what to call it) from R=Ha, G=70%O3+30%Ha, B=O3. Processed it as LRGB using a combined Lum from 60% Ha L and 40% O3 L.
I am really happy that I finally feel satisfied with a target! Usually I just get restless and move on when half of the data is collected.
Hope you like it!
I scrapped all the Oiii and Sii data I previously took during a full moon (about 15 hours worth) and retook it all when the moon was a bit smaller at 76%. Ha was taken during 98% and 67% moon. All the lights were taken on the following nights: 12th, 19th and 20th September 2019.
Integration times, all in 600s subs unbinned:
Ha = 28.33 hours
Oiii= = 5.67 hours
Sii = 5.67 hours
The Ha data is really nice, and unsurprisingly the Oiii and Sii is not as strong (or nice).
I'm missing that (vital) step in my processing routine of getting the Sii and Oiii properly stretched to match the Ha, before combining. I dont really know how to deal with the weaker data properly. Any pointers would be appreciated.
What I do currently:
All the data is loaded into APP into separate channels/sessions.
The data is stacked and registered against the best Ha sub
This produces individual stacks of Ha, Sii and Oiii that are all registered
Each channel is processed with DPP in APP and then saved as a 16bit TIFF
Each is opened in PS
Stars removed with AA and any remnants removed and tidied up
I then open a blank RGB document in PS
I paste Ha into Green, Sii into Red and Oiii into Blue
Adjust the selective colour settings to get 'Hubble palette'
Adjust levels, curves, saturation until looks ok
All the Ha Sii Oiii data is then combined together in a single 'super' stack in APP using quality weighted algorithm to create a 'luminance'
That luminance layer is adjusted using levels, curves, and NC tools such as local contrast enhancement and deep space noise reduction (using masks to apply as required)
The luminance is pasted onto the above colour layer, and incrementally added using gaussian blur
Cropped and saved.
Here it is anyway I haven't intended on any more exposure time for this one, but will consider it, if the expert opinion dictates otherwise!