LP-filter?

[turboscrew]

I was thinking that maybe some LP-filter might enhance the view.
Is there drawbacks in having an LP filter "permanently" kept in the tube end of ES HR? And what kind of LP-filter would be good used that way - mostly for visual for now.
(I haven't checked if there are filter threads in the ES HR tube end, but I was thinking about something like that.)

[Lady Fraktor]

What is a ES HR?

[yobbo89]

What is a ES HR?

maybe this

https://www.telescopehouse.com/explore- ... ector.html

i don't know much about visual, but don't most people use some sort of visual filter like h-beta,oiii ectt, wouldn't those two be more effective as a lp cut down.

[Bigzmey]

I would not recommend keeping LP filter permanently on your scope. Most of the targets (galaxies, globs, stars, planets) we observe do not benefit from LP filters, but these filters cut light transmission and change colors of what you see, so would be actually worthening the views for these targets.

However, LP or nebula filters do help to visualize emission nebula. If you have just one filter that would be narrow band (UHC). I would recommend Lumicon UHC, Astronomik UHC or Orion UltraBlock. If you have budget you can also pick OIII and H-beta filters.

Filters which typically called light pollution or sky glow are broad band filters. They don't help that much with LP, so they would be the last thing on my list. Some of them can be useful in other ways, for example Baader Moon and SkyGlow is a good filter to use for planets in particular Jupiter. I also use it on occasion to pull a galaxy or glob from a light dome near horizon.

[Refractordude]

I bought all the filters for achromatic refractors and returned them, because they were useless. Useless for me, but may work for others. We are all physically different. I tried a moon filter on Mars. It changed the color of the planet to a very light grayish white, but seemed to show more or just as much surface detail. I remember my observations like a kind of dream. So I will have to test the moon filter again to be sure. Buy from Walmart or Amazon. Both pay for return shipping.

[turboscrew]

What is a ES HR?

maybe this

https://www.telescopehouse.com/explore- ... ector.html

i don't know much about visual, but don't most people use some sort of visual filter like h-beta,oiii ectt, wouldn't those two be more effective as a lp cut down.

Yes, exactly that. I should have been a bit more verbose.

[turboscrew]

Thanks. I guess I don't get one then.

[kt4hx]

I have an Orion Sky Glow, which is a broad-banded filter marketed to help with LP. These filters have limited utility for visual use. In reality, the more LP one has the less they help. Very heavy sky glow will swamp the filter rendering it useless. But even in dark areas, their utility is limited. I have seen some very modest improvement in the visual presentation of some galaxies and nebulae in modest to low LP conditions, but the improvement is quite subtle. An experienced eye can discern it, but it likely would not be obvious to the beginner or casual observer. I feel it is a filter that most need not spend their money on. Simply put, if you cannot already see the object without the LP filter, you will not magically be able to see it with one.

The above said, for imaging, they can certainly be beneficial because the camera is more sensitive than is the eye. They market LP filters specifically for imaging and those can be used with slightly better results visually than those sold as "visual" filters. But again, any visual results will be subtle.

As Andre mentioned, and I agree, the best all around filter one can have, if they have only one, would be the narrow-band nebula filters, such as the Orion Ultra Block or DGM NPB (to name two I own). These will work with a great number of nebulae, both emission and planetary. An O-III filter is considered the premier filter for planetary nebulae and is a good second filter to own.

[Baurice]

I used one to research the Messier objects. It made many objects fainter but M101, a galaxy in Ursa Major, appeared three times wider than without the filter. The short answer is just to try it on different objects. Overall, I found for galaxies, it improved most of them but it was not so good for open star clusters.

[mikemarotta]

I went to the source, Explore Scientific.
https://explorescientificusa.com/produc ... -corrector

It is called HR for Harrie Rutten, the inventor. (Our software here wants that to mean "Herzsprung-Russell diagram.")

You got your answers, I think, and I appreciated all of the shared opinions. I was also looking at a Light Pollution (LP) filter. I live in the city and I am a mile from a major shopping center. But the opinions here gave me pause. One thing about Explore Scientific, I was on the phone with them and wanted to buy a bunch of eyepiece enhancements and the customer service representative warned me that as coated and perfected as everything is, the absolute objective fact is that the more glass you put between you and the stars, the less you see. In other words, you have your basic optics that are designed to be a certain range of operations and that's what they do.

That said, I was happy to be able to use a Moon filter on Venus to see the phases. The other filters in the kit don't do that much for me.

And being in the city, if I were to have bought the 5X focal extender, all I would have is a five times bigger and brighter view of a faint, dirty image. Want a better image? Getting out of the city will do more for you than an LP filter.

[turboscrew]

It looks like my LP is mostly from sodium lamps. It was revealed to me in a cloudy/foggy might when the lights from a nearby road gave the same colour as the lights from 3 km away. The nearby street lights are so compared to my place, that normally they don't cause problems, but the fog makes it visible.
I wonder if they are low pressure? The light is orangish yellow, but the light reflected by clouds is rather yellowish pink.

[GCoyote]

I got and inexpensive LP filter last week. Since Mars is so bright right now I tried it on that. Looking at red-ish Mars through a multi-band filter gave a modest increase in contrast.

Full disclosure: I have a condition similar to macular degeneration that significantly affects my color vision. Your results may vary.