42 replies to this topic

[3C286]

I have a Celestron Starsense 8 inch dobsonian. Most of the times, the Starsense app can't find position and doesn't work at all. Followed all the problemfixing tips from Celestron, but still nothing. Strange enough, I'm one of the few people having problems with the app.
At the moment, I try AtroHopper and hope this will work better, but I can say allready that I don't like the layout. Terrible colouring and very unclear. Also, working with the very little green arrow is a pain in the butt. I didn't need glasses with the Starsense app, but I absolutely need them with AstroHopper. 

Personally, I also want to learn to find the objects in the sky by hand and my own mind. At first, I look at Stellarium on my laptop to locate where it is, looking at the constellations / stars. Of course, with the moon the smaller stars disappears and this makes it more difficult. I have no finder scope, but I have a red dot finder. After using this, I use the 25 mm eyepiece.  

I feel for you. You have a really difficult set up for star hopping on your StarSense Dob.

 

As others have mentioned, you need a RACI finderscope. My RACI has a 5.4° TFOV compared to the 1° TFOV through your 25-mm eyepiece. That makes a big difference for finding things efficiently. To make the workflow efficient, you want your RACI near the eyepiece. You also want a 1x finder like your RDF or Telrad near your EP rather than on the other side like on the StarSense Dob. Is the RDF on a standard quick release? If so, a three-way finder adapter bracket might give you enough reach? Alternatively, you'll probably need to take out the spider, drill some holes and fit a finderscope bracket.

 

A laptop isn't a good way to starhop. You either want a paper chart or a paid version of SkySafari or Stellarium on your phone/tablet with a dark red filter. On SkySafari, you can place a circle with crosshairs the size of your finderscope and eyepiece's TFOV which you can use to compare against what you see through your scope. 

 

Good luck

Tak

[Sebastian_Sajaroff]

On my old 6", Eskimo nebula was much easier than Owl.
Eskimo looked like a tiny blurry star at 40x, and became more evident at 80x.

Like others said, deep sky requires no Moon, a transparent night (no fog, smog, haze, cirrus) and ideally no light pollution. Make sure your eyes are dark adapted.
RACI will help you a lot to point to the PN area.
Binoculars can also help you to get familiar with the area.

[Dave Mitsky]

An article on observing bright planetary nebulae is available at https://www.astronom...-the-night-sky/

[Whiteduckwagglinginspace]

I feel for you. You have a really difficult set up for star hopping on your StarSense Dob.

 

As others have mentioned, you need a RACI finderscope. My RACI has a 5.4° TFOV compared to the 1° TFOV through your 25-mm eyepiece. That makes a big difference for finding things efficiently. To make the workflow efficient, you want your RACI near the eyepiece. You also want a 1x finder like your RDF or Telrad near your EP rather than on the other side like on the StarSense Dob. Is the RDF on a standard quick release? If so, a three-way finder adapter bracket might give you enough reach? Alternatively, you'll probably need to take out the spider, drill some holes and fit a finderscope bracket.

 

A laptop isn't a good way to starhop. You either want a paper chart or a paid version of SkySafari or Stellarium on your phone/tablet with a dark red filter. On SkySafari, you can place a circle with crosshairs the size of your finderscope and eyepiece's TFOV which you can use to compare against what you see through your scope. 

 

Good luck

Tak

The red dot finder has a quick release. The red finder is allready a quite far reach, because of the Starsense Dock, which is placed on the top of the OTA.

I have 3 binoculars (10 x 35 / 12 x 50 / 15 X 56) and a few spotting scopes (85 mm), but I'm not sure this is a good substitute for star hopping. 

[Whiteduckwagglinginspace]

An article on observing bright planetary nebulae is available at https://www.astronom...-the-night-sky/

That looks like a nice and learnsom article. Certainly going to read that. Thank you!

[Whiteduckwagglinginspace]

What I want to say: so many people on this thread really made quite some effort to give help and information. It is really heartwarming and I want to thank you all! For this reason alone, you should take up this hobby. Thumbs up for the amateur-astronomers community!

[sevenofnine]

Perhaps I missed it in this thread but a basic guide book like "Turn Left At Orion" by Guy Consolmagno and Dan M. Davis really helps finding many objects including PN's. The authors of this classic know how difficult it can be to find objects especially when you're new to this. The objects are shown in realistic sketches rather than pictures so you really know what to look for in an amateur scope. Good luck! 

[3C286]

The red dot finder has a quick release. The red finder is allready a quite far reach, because of the Starsense Dock, which is placed on the top of the OTA.

I'm afraid it sounds like you might need to remove the StarSense dock and drill some holes to install a finderscope bracket...

 

I understand you want to go manual but another option might be to try a different phone for the StarSense? If you want to try another electronic finderscope, you could fit a PiFinder/Cedar where the RDF is via a three-way adapter. Once aligned, they are very accurate and you'll get your target inside your 25mm EP's FOV.

 

I have 3 binoculars (10 x 35 / 12 x 50 / 15 X 56) and a few spotting scopes (85 mm), but I'm not sure this is a good substitute for star hopping. 

Unfortunately, the finderscope needs to be fixed to the scope and aligned. You should be able to get a 8-10x50 RAC finderscope like the one linked below. Make sure that it's Right Angle Correct Image (RACI) type and has at least 5° FOV. It's quite a lot of work and not and not an insignificant amount of money but I think you'll find that it's a worthwhile investment that'll make star hopping an efficient and fun experience.

 

https://www.highpoin...racket-a-fra850

 

Binoculars are handy to have. I often scout out the area with my binoculars before star hopping, for example to look for good starting points.

 

 

I hope that gives you some options. Good luck.

Tak

[RichA]

Two questions about finding Planetary Nebula:

First question: how much influence has the moon on finding Planetary Nebula?

Second question: can you find Planetary Nebula without a filter?

Thanks for helping!

1.  Almost none.

2.  Yes.  Planetary nebula can be small,  it's best to know where you are (Goto, setting circles, star hopping) and to use magnifications above 50x.

[Whiteduckwagglinginspace]

1.  Almost none.

 

Thank you for your answer, but this answer is a bit confusing, because the other people in this thread said the opposite.

[Jon Isaacs]

1.  Almost none.

2.  Yes.  Planetary nebula can be small,  it's best to know where you are (Goto, setting circles, star hopping) and to use magnifications above 50x.

 

As Don said, there are a great variety of planetary nebulae. Some are small and bright. Some are diffuse and faint. 

 

The Owl nebula is magnitude 9.8 and 3.3 arc-seconds x 3.4 arc-seconds. The surface brightness is 21.0 mpsas, the darkest skies are 22.0 mpsas, bright urban skies are 18.0 mpsas. It's a logarithmic scale, 18 mpsas is about 40 times brighter than 22 mpsas.

 

The moon only makes things brighter and would make the Owl, already difficult to see, even more difficult.

 

Jon

[artik]

At the moment, I try AtroHopper and hope this will work better, but I can say allready that I don't like the layout. Terrible colouring and very unclear. Also, working with the very little green arrow is a pain in the butt. I didn't need glasses with the Starsense app, but I absolutely need them with AstroHopper. 
 

1st you can increase the font size in settings to make it suitable for your needs

Regarding coloring - in night mode it is all red   (also in settings)

[RichA]

As Don said, there are a great variety of planetary nebulae. Some are small and bright. Some are diffuse and faint. 

 

The Owl nebula is magnitude 9.8 and 3.3 arc-seconds x 3.4 arc-seconds. The surface brightness is 21.0 mpsas, the darkest skies are 22.0 mpsas, bright urban skies are 18.0 mpsas. It's a logarithmic scale, 18 mpsas is about 40 times brighter than 22 mpsas.

 

The moon only makes things brighter and would make the Owl, already difficult to see, even more difficult.

 

Jon

Except the moon is nowhere near the Owl nebula which is in the north, a decent enough distance so the moon even when full wouldn't wash it out.  Of course, I'm basing this on using at least an 8 inch scope and a UHC or OXYIII filter.

[Nankins]

Two questions about finding Planetary Nebula:

First question: how much influence has the moon on finding Planetary Nebula?

Second question: can you find Planetary Nebula without a filter?

Thanks for helping!

The moon has a lot of influence on finding most DSOs outside of star clusters. However, bright planetaries such as M57 aren't usually bothered by it.

As for using a filter, that depends on the filter - some respond better with a UHC filter while others have more OIII. You will typically use a UHC for planetaries. You can find the bright ones without a filter, but many will just look like a fuzzy or off-colored star. The bright planetaries such as M27 and M57 can still be impressive without a filter - you just won't be as likely to see detail or color. For anything other than bright and large planetaries, you can see the difference by first finding the star field without a filter and trying to identify the nebula. Then pop a filter in and see if you can make out the nebula after that.

[Whiteduckwagglinginspace]

1st you can increase the font size in settings to make it suitable for your needs

Regarding coloring - in night mode it is all red   (also in settings)

Thank you for your advice, and a big(!) thank you for making this app for free! This great action is almost unworldly, in today's world.

I don't use red (night mode), because I find this color makes things more unclear to see.
Increasing the front size will help me, thanks!

If you can change something, please make this green little arrow more clear. (I can see it only with glasses and from a close distance) Take for example the arrow made by Celestron/Starsense: their layout is perfect. (I know: can't complain about something which is for free.)

 

[Starman1]

Thank you for your advice, and a big(!) thank you for making this app for free! This great action is almost unworldly, in today's world.

I don't use red (night mode), because I find this color makes things more unclear to see.
Increasing the front size will help me, thanks!

If you can change something, please make this green little arrow more clear. (I can see it only with glasses and from a close distance) Take for example the arrow made by Celestron/Starsense: their layout is perfect. (I know: can't complain about something which is for free.)

 

Increasing font size will make words easier to read in red.

You are hurting your night vision with other colors.

Edited by Starman1, 12 February 2025 - 02:27 PM.

[EsaT]

Thank you for your answer, but this answer is a bit confusing, because the other people in this thread said the opposite.

Moon is far too bright to allow your eyes to achieve good dark adaptation hurting visiblity of anything not very bright. Besides adding some glow to sky.

Though being in observatory with its roof blocking side of the sky with Moon on it would allow better dark adapting.

But don't think that applies to you.

 

 

As for eyepiece for wide views Svbony 26mm SWA would be likely the cheapest if shipping cost is at usual level:

https://www.svbony.c...26mm-70-degree/

 

GSO 30mm SuperView would be still litlte wider and give ~60% wider view than 25mm Plössl:

https://www.firstlig...w-eyepiece.html

 

Though both are old low end designs and not the cleanest in outer field.

But next step up in quality costs lot more:

https://www.firstlig...2-eyepiece.html

28mm UWA would be still little wider.

But eye relief is very medicre for the AFOV and seeing field edge takes some effort, unless your head/face shape is favourable. Also it's definitely incompatible with glasses.

 

Here's some FOV comparison using Pleiades as scale:

https://astronomy.to...|1||&messier=45

 

 

You're also missing medium magnification step to observe non-wide deep sky objects like Orion Nebula and for squeezing details out of nebulous objects like dust lanes in Andromeda Galaxy.

2" Barlow could make those double for that. Especially 26mm would give almost 2mm exit pupil.

[WillR]

Except the moon is nowhere near the Owl nebula which is in the north, a decent enough distance so the moon even when full wouldn't wash it out.  Of course, I'm basing this on using at least an 8 inch scope and a UHC or OXYIII filter.

But overall sky brightness will wash it out. I generally observe DSOs from a 3rd quarter moon (rises after midnight) to about 1st quarter when it really begins to impact them.