About Field-Flatteners, Coma Correctors and Reducers | DSLR Astrophotography
Вставка
- Опубліковано 26 бер 2019
- Welcome back people :)
ever wondered how coma correctors and field flatteners work, and wha they are for? Let's find out!
Exploring the universe one image at a time! Come follow me on this journey, be an AstroAddict :)
Are you interested in supporting the channel?
Do you want to practice Deep Sky editing, but you lack the actual imaging data? I am sharing my imaging data over on my Patreon page.
My Patreon supporters will recieve this data, aswell as some more in-depth tutorials an insights of my work. As to this date (5th of September 2019), this idea is still very young, and i'm still trying to find a good path.
If you wish to support me, head over to the Patreon page:
/ astroaddict
Thanks for your time!
____________________________________________
Images used (Attributions):
1.) By Original uploaded by DrBob (Transfered by nbarth) - Transferred from en.wikipedia to Commons.SVG version of Image:lens6b.png, CC BY-SA 3.0, commons.wikimedia.org/w/index...
2.) Von Stan Zurek - Eigenes Werk, CC BY-SA 3.0, commons.wikimedia.org/w/index...
3.) Von Der ursprünglich hochladende Benutzer war Tallfred in der Wikipedia auf Englisch - Originally from en.wikipedia; description page is/was here., BSD, commons.wikimedia.org/w/index...
____________________________________________
I hope you have a wonderful day/night wherever you are!
Clear skies, and may the night be with us! - Наука та технологія
I think you are confusing chromatic aberration, a problem for refractors, and coma, an issue that often plagues mirror telescopes where all wavelengths are brought to a common focus since refraction does not occur. The former problem can be alleviated using auxiliary lenses while the latter can be improved by adding a coma corrector in the optical path. Also, astigmatism can be an issue for circular pupils, as in the case of the human eye.
Thank you for explaining the difference. Its so helpful :)
More than happy to come across your channel :)
Great video!Would love to see you make a video on camera tilt and how to fix it, and properly calculating back focus for focal reducers.
Very good information!
great video
Great info. Thanks.
How odd. This video was posted about 5 minutes before I decided it was time to google field flatteners. Thanks mate!
Let's say it was fate😀
Thank you so much for the explanation.
These are actually getting better!
The videos?
@@AstroAddict obviously
Thank you very much. I got answers on all my questions :)
Thanks, that's nice to hear😊
Great instructional video. I am wondering though, what editing software did you use for your video?
Nice video. :)
Nice video and informative. I particularly enjoyed your editing :)
A+
Thanks for the video! This will help me pace myself and focus on learning before spending!
That said, do you think it is possible to reach prime focus using a focal reduction lenses? DSLR camera sensor is still too far from secondary mirror and was wondering if a focus reducer lenses could help reduce that distance. Thanks!
A reducer will indeed shorten the focal length. Quite literally, the distance from main plane to focus point will get shorter. You could do some calculations and maybe contact the vendor, to figure out what type of reducer would be best
Are you going to NEAF next week?
Great stuff!!
That would be 8 hours in the plane, and i have to work🤔
Well you do get vacation? 😁
My vacation is almost over... had to take it Feb/Mar cause of exams
@@AstroAddict all the best! enjoying your videos!
hello! do you recommend getting a reducer for an 80mm telescope? what's it useful for, apart from photographing very large things in the night sky? thanks for this video!
Well, it's only job is to do just that. Reduce the focal length, and ratio. Maybe look into a reducer/flatterner combination if you want to upgrade
@@AstroAddict If that's the only job of a reducer then I guess it doesn't do flattening. I am considering a lower cost brand of triplet that I may use for photography later but when I search I don't find a particular flattener for it.
Should I avoid that model/brand or is there a way to find a flattener that would be suitable e.g. 3rd party? They have a reducer which doesn't mention 'flattener' and their web page says it's for their bigger model. Maybe I need to call and ask!
Actually you can use a achromat for astrophotography if you are shooting with a mono camera through narrow band filters.
Never said you couldn't
That is true. By the way I enjoy your videos. Perhaps next year yo can come to NEAF once you get some sponsors. @@AstroAddict
Let's see how it develops☺
I just got my William Optics Zenithstar 81 APO two days ago....Looks great but I was unable to connect my Canon 5D or M50 successfully, using a cheap 5x barlow lens and a T-ring. Did not focus ... do I need a 10 cm extension tube for a DSLR on this telescope ???
Wait wait wait wait wait. You connected a barlow lens to a short telescope? That's like using a 5000$ PC to run Minecraft. Ditch the barlow, and connect the camera directly. The barlow multiplies 5 to every stat of the scope. Focal length, aperture... and backfocus. That's why you could not reach focus. Furthermore: The telescope you have is high quality. Using a cheap barlow will make it useless. The system is as good as the cheapest part
Do you need a field flattener if not using a DSLR camera.. Eye piece or CMOS Camera instead
Yes, i usually keep the FF in the scope for everything
Tim pardon my ignorance, I'm new to astro photog. Does a newtonian require a field flattener? .. a newtonian with a parabolic mirror that is.
I have no experience with mirrors, sorry
Newtonian reflectors require a coma corrector. Reflectors require a field flattener.
Das Thumbnail ist schon cool 😂
Das war das erste mal das ich beim Aufnehmen der Thumbnails Spaß hatte😀
@@AstroAddict lemme guess, google translate is the answer
Was wondering why mine stars are so bad around corners and found this video :D so i looked at the price of field flatener and it was double triple of mine scope so i think i will live with it because i am cheap ass :D Mine next scope will be quadruplet to fix all these issues :D
00:38 dont judge him, he only likes some extra color ;-)