M57

[MilAN]

Nejjasnější planetárka v H-alfa :

popis :http://astrofotky.cz/gallery.php?show=. ... 640134.jpg

[blackhaz]

M57 RRGB (L=R) 2x30 min, 254mm Maksutov-Cassegrain, prime focus f/15

Velmi rychle zpracovani v PixInsight

[Roman (Rick)]

Nice work. A lot of details there ... .

[blackhaz]

Thank you, Rick!

Final version on this data. Exposures were too low so I had limited deconvolution options here.


Full info about this frame:
http://www.bcsatellite.net/bao/M57/m57.html

[Vabra]

I'm not sure whether you can follow the other discussion here about the usefulness of the long focal length telescopes in central europe (e.g. that everything above 1m is irrelevant due to the seeing).

But this wonderfull shot from Prague is great illustration that it might have very good sense. Do you know what was the typical FWHM on your individual shots in arcsec?

thanks,

[blackhaz]

Hi Pavel,

I haven't been following honestly - haven't found it, but will look around now. Typical FWHM was around 1.6" to 1.8". A few shots were 2.0". The stack of 30 frames resulted in 1.6" which is rather good. 1.8" is something I can achieve on my terrace in Prague rather often these months, I wonder if it will be the same during autumn and winter. I was really surprised by the seeing I have here in Prague during low 300mb jet stream seasons because I typically encounter 2.5" and above with a 12.5" RCOS in New Mexico.

I am sure that had I made more exposures and, say, at least 5m each, the image would have been much, much better, so I think there's a great potential. The current dataset was extremely limited by SNR, but that's just my first attempt at the prime focus and I am still learning a lot.

[Vabra]

haven't found it, but will look around nowhttp://www.astro-forum.cz/cgi-bin/yabb/YaBB.pl ... 2520/39#39

In contrary with your experience most of our colleagues see the 3" as the typical limit here...

[blackhaz]

I am sorry for the off-topic, however the major role here comes from the very exact spot the telescope is located. Installing the telescope just randomly won't produce any good results. One has to study all the local environment factors and select observing site carefully. Second role comes from the telescope build and optical quality: how well it cools down, central obstruction and other factors. I wish I knew Czech better to write on this topic in that thread.

Once again, pardon for off-topic.

[PDlink]

Pridam jednu s priemernym seeingom    :(



tech. par. na http://www.hvezdarnicka.sk/?menu=299&lang=1

[blackhaz]

Dobry M57! Myslim ze s 36cm Newton muzes pouzivat 2x Barlow na tento mlhovine.

[Ondra.P]

Re:blackhaz, PDlink

Oba dva perfektni prace!

[PDlink]

To blackhaz: planujem to. Som zvedavy na vysledok.

[Pavebo]

Zdravím ''zes'' Plzně a přikládám první pokus o M57 přes ACF 10'' v zákl. ohnisku 2500 mm->legenda je u obrázku na Astrofotkách:

http://astrofotky.cz/gallery.php?show=. ... 673246.jpg

Zdraví

Pavebo

[Sasa3]

to Pavebo: pekny detail. Zkusil bych jeste neco udelat  s barvou. Ten cerveny okraj se temer vytratil a zustala prakticky jenom modra.

[Pavebo]

to Saša3: trochu jsem tomu pomohl, když jsem viděl jak se tam při takové barevné kombinaci zjevují stále vice a více detaily...a na ty já jsem hlavně zvědavej. Mám zkušenost, že mnoho pěkně kolorovaných snímků má právě detaily ''sežrané'' díky přelití červenou barvou...
Nicméně, až udělám HA tak ji tam bude něúrekom.

Viděl jsem tvoji planetárku na Astrofotkách a ta je úžasná!

Zdraví

Pavebo