Backyard astronomers, how do you decide what to look at?

  • Stargazing
  • Thread starter Nick-stg
  • Start date
In summary: Objectsthat I hoped to see end up being obstructed.Wandering around Stellarium (or equivalent) is interesting fun and you can do it any time. I have found that Stellrium etc. will show you...
  • #36
George Jones said:
On the other hand, a UHC filter reduces the intensity of all wavelengths, except wavelengths typically emitted by nebulae,
That was my understanding. Thank you for confirming. But what about the h-alpha, h-beta, O-III etc.. based on their descriptions these appear to do the same thing as the UHC filters. What's the difference?
 
Astronomy news on Phys.org
  • #37
Nick-stg said:
That was my understanding. Thank you for confirming. But what about the h-alpha, h-beta, O-III etc.. based on their descriptions these appear to do the same thing as the UHC filters. What's the difference?

While I have an 8-inch scope, I don't own any filters, and I am not much of a guide for them. Try

https://starizona.com/tutorial/narrowband-imaging/
 
  • Like
Likes Nick-stg
  • #38
sophiecentaur said:
I’m not so sure that the reduction in luminosity is great enough with polarisers . Iirc, my ND is 12% and even that’s pretty bright.
on the filter I got (Orion Variable Polarizing Filter), you can adjust the amount of light transmission from 1% to 40%. Very practical, as you can appreciate different transmission in case of full moon, and different one in case of observing Jupiter (I noticed that some very fine details can be enhaced by using the filter even with Jupiter).
 
  • Like
Likes russ_watters
  • #39
Nick-stg said:
But what about the h-alpha, h-beta, O-III etc.. based on their descriptions these appear to do the same thing as the UHC filters. What's the difference?
Narrow-band vs broad band. Those that specifically identify an emission line block everything except that emission line. UHC filters have a broad band of what they let in and/or a narrow band of what they block (sodium-sulphur lines from street lights, for example). It's all described in the product details:

https://www.highpointscientific.com...AlF9u7D3DkxBz0fxXVsgV4eoO03C9h_caArNcEALw_wcB
 
  • Like
Likes davenn
  • #40
lomidrevo said:
on the filter I got (Orion Variable Polarizing Filter), you can adjust the amount of light transmission from 1% to 40%. Very practical, as you can appreciate different transmission in case of full moon, and different one in case of observing Jupiter (I noticed that some very fine details can be enhaced by using the filter even with Jupiter).
I totally agree. I never bought those. Probably more expensive than an nd filter? I must admit that I was commenting on a straight photographic polar
 
  • #41
Nick-stg said:
That was my understanding. Thank you for confirming. But what about the h-alpha, h-beta, O-III etc.. based on their descriptions these appear to do the same thing as the UHC filters. What's the difference?
The UHC filter idea is a compromise between cutting out what you don't want to see (visually) and letting as much in that you do want. The resulting image is not quite as bright, of course but if you exclude nearby light sources and get light adapted, you can see a lot and the contrast is improved, of course. Astrophotography uses narrow band filters, for instance H-alpha (which will show you virtually nothing visually) and you use long exposure times (tracking and possibly guiding needed). Separate exposures with each filter produce a set of images which can be mixed to taste.
 
  • Like
Likes russ_watters
  • #42

Attachments

  • 1589589211988.png
    1589589211988.png
    116.8 KB · Views: 291
  • #43
chemisttree said:
I can’t believe the prices though
Annoying innit? But think of the man-hours in quality checking and the cost of low volume sales. Then realize that 'enthusiasts' in any field are suckers. At least you can measure the results here - unlike with the snake oil that goes into most HiFi equipment.
 
  • Like
Likes Nick-stg
  • #44
sophiecentaur said:
unlike with the snake oil that goes into most HiFi equipment.
Don't get me started on that one...
 

Similar threads

  • Astronomy and Astrophysics
Replies
14
Views
2K
Replies
4
Views
3K
  • STEM Career Guidance
Replies
2
Views
1K
  • General Discussion
2
Replies
66
Views
6K
  • Art, Music, History, and Linguistics
Replies
1
Views
1K
Replies
12
Views
2K
Replies
7
Views
21K
Replies
10
Views
12K
  • Sci-Fi Writing and World Building
Replies
1
Views
3K
  • STEM Academic Advising
Replies
7
Views
1K
Back
Top