1978 replies to this topic

[Astronoob76]

So I have to go out ???

Certainly not. I'm not much of an "astronomer" (so far) either. I basically look at the same 3 or 4 things I can easily find. Pleiades, Orion Nebula and M31. Apart from that I just roam the sky and look at whatever seems nice to look at - which is mostly everything. I probably can spend the rest of my time on this earth by simply doing that and be happy. I do plan on getting more into it in the summer and try to find some other interesting things. But I'm lucky with the sky here. I can see the milky way with bare eyes.

[ECP M42]

Without the shared philosophy of Burnham’s Celestial Handbook, we cannot have a meaningful exchange of ideas.

  ... ma nun ce posso crede! 

 

 

Translation: ... but I can't believe it! 

 

Henry

Edited by ECP M42, 08 December 2021 - 06:58 PM.

[Fiske]

But this is an astronomy forum???

A minor detail...

 

[Fiske]

From home, with 10x42 (for example) I can't see HIP 14030 - SAO 130241 (8.7 magn). 

Henry, good job providing a specific star reference that others, including myself, might be able to observe and follow up about.

 

The star you reference is in Eridanus. Based on Germany's latitude of 51 degrees north, compared with Kansas City's latitude of 39 degrees north, I'm guessing this star must be fairly low in the sky from your location? Atmospheric extinction is a significant problem when observing from light polluted sites in particular. You will be able to see fainter stars near the zenith.

 

Anyway, I'll see if I can observe it from my yard and follow up about its visibility with various members of team 10x. 

Edited by Fiske, 08 December 2021 - 02:26 PM.

[Fiske]

Also, based on this stargazing.net chart, if you are able to see stars in the 7.5 to 8.49 magnitude range with a 10x42 binocular, that is a total of 77,627 stars that can be seen (across the whole sky). In other words, from your light polluted site, with a 10x42 binocular, you can see more stars than can be seen naked eye from the darkest site on the planet. It's a different experience, needless to say. But, still a simple demonstration of what is possible with a binocular. 

 

Saying that if you can't see something naked eye you aren't interested in looking at it with a binocular is puzzling to me. The fun and value of a binocular (in any context) is that it enables you to see things that otherwise would be unseen. It's akin to saying you wouldn't be interested in looking through a microscope to see things that aren't visible without it. 

 

I guess what I'm hearing is that you aren't interested enough, or excited enough, about observing the night sky, to expend the effort and time necessary to find your way around it.

Edited by Fiske, 08 December 2021 - 11:09 AM.

[Mark Y.]

Gotta' say Fiske....What a helpful and class act you come across as!

[Fiske]

Thank you, Mark. 

 

Welcome to Cloudy Nights.

 

[The Ardent]

Astronomy is like the Matrix. A majority of people prefer the simulation (internet , movies, TV) over reality (the night sky)

[Fiske]

Astronomy is like the Matrix. A majority of people prefer the simulation (internet , movies, TV) over reality (the night sky)

I could look endlessly at the night sky with binoculars. I'm enchanted with it.

[ECP M42]

Henry, good job providing a specific star reference that others...

The star you reference is in Eridanus ... compared with Kansas City's latitude of 39 degrees north, I'm guessing this star must be fairly low in the sky from your location?

 

Anyway, I'll see if I can observe it from my yard ...

Thanks Fiske, but I'm just trying to understand your claims in a scientific way. And if in the meantime I learn something new about the stars, it's all earned (so be it).
From my position (45° North) I should have seen that star at about 38° of elevation (about 10:40 pm).
You should "see" it higher in the sky. 

 

 

Saying that if you can't see something naked eye you aren't interested in looking at it with a binocular is puzzling to me. 

In fact, I've never said anything like that. And I honestly don't understand why my words are constantly being misunderstood. I said that I simply won't waste the nights trying to see invisible objects in my binoculars. And I think any normal, sane person has these intentions.

Binoculars are certainly one of humanity's best inventions, but they can't do miracles.

So, if I want to see a star that I don't see in 10x42, I'll use an 18x50 or something more powerful. There is no need for a genius to understand this obviousness. 

 

 

I guess what I'm hearing is that you aren't interested enough, or excited enough, about observing the night sky, to expend the effort and time necessary to find your way around it. 

This is partly true. But that's normal. I am also interested in observing the animals that populate this Earth (like others), but I have no interest in becoming an Ornithologist, Ethologist or Biologist. I hope this doesn't cause any problems for anyone. 

 

I am on the Binoculars forum to talk mainly about binoculars. 

 

Here came the snow!     

 

Henry

[gwlee]

Beyond the Moon and the brightest planets, what's so interesting to observe under a polluted Bortle 8 sky?

Henry,

 

Here are three excellent publications that will answer your question in great detail, and perhaps start you on the road to becoming an astronomical observer. I found them very useful under a Bortle 9 sky.

 

1. Night Watch-A Practical Guide to Viewing the Universe by Terence Dickinson

 

2. Observer’s Hanbook by The Royal Astronomical Society of Canada

 

3. Binocular Highlights-99 Celestial Sights for Binocular Users by Gary Seronik

 

 

Gary

Edited by gwlee, 08 December 2021 - 10:47 PM.

[Fiske]

The 25mm aperture masks are finished and ready for action. Completely cloudy tonight, of course. Hearing someone talk about using a 10x25mm binocular for astronomy it's hard to visualize what a dramatic reduction in light gathering capability that represents compared with a 10x50mm binocular. Seeing the actual difference, you just have to smile and shake your head. It's not half the the light. It's a quarter of the light!  Oh well. Observations to follow. 

 

 

 

Edited by Fiske, 08 December 2021 - 10:13 PM.

[ECP M42]

 

Positioned this far from the entrance pupil, they should reduce distortion as well. 

 

But those perfectly cut yellow cards have a very (too) high albedo. 

If you can blacken them with matte paint, they will certainly work better. 

 

I await the tests. Here too it is cloudy, as usual. 

 

 

ps: The eyes can see such a luminous excursion that the minimum and maximum level is generally within 30,000,000 times.

What do you want them to be 4 times?    

 

Henry

Edited by ECP M42, 09 December 2021 - 12:54 AM.

[Grimnir]

The 25mm aperture masks are finished and ready for action. Completely cloudy tonight, of course. Hearing someone talk about using a 10x25mm binocular for astronomy it's hard to visualize what a dramatic reduction in light gathering capability that represents compared with a 10x50mm binocular. Seeing the actual difference, you just have to smile and shake your head. It's not half the the light. It's a quarter of the light!  Oh well. Observations to follow. 

 

Hi Fiske,

 

I'd especially appreciate a brief comparison of lunar views in your Fuji 10x50, with and without your aperture masks.

 

The Moon is extremely bright in my Fuji 10x50 and I suspect that stopping it down would improve lunar views. If your comparison confirms this I'll make my own masks though I'll probably use spare lens caps rather than card.

 

Graham

[Fiske]

Hi Fiske,

 

I'd especially appreciate a brief comparison of lunar views in your Fuji 10x50, with and without your aperture masks.

 

The Moon is extremely bright in my Fuji 10x50 and I suspect that stopping it down would improve lunar views. If your comparison confirms this I'll make my own masks though I'll probably use spare lens caps rather than card.

 

Graham

Graham,

 

Yeah. I'll put that on the program. I'm more interested in masking for lunar views from an optical perspective than for observing deep sky, which I anticipate is more or less going to be an exercise in debunking.  (In a friendly and at least somewhat objective way -- specific reports will be provided for identifiable objects and star fields.)

 

I didn't have black spray paint, but did have some oversized black magic markers, so those were used to darken the aperture masks front and back.  It was supposed to be clear tonight, but is cloudy now so we will see how the evening goes.

Edited by Fiske, 09 December 2021 - 06:50 PM.

[Fiske]

In a further Team 10x development, I have decided to evaluate a Maven b.5 12x56 versus the 10x56 now on my team. My particular interest is comparing edge performance between the two -- expecting that at 5.5 degrees (12x) versus 6.5 degrees (10x), the 12x edge performance may be a step up. Maven has a reasonable home evaluation program so the instrument is being shipped as a demo. Net out of pocket is only the cost of return shipping.

 

If the instrument is returned...

 

[f18dad]

The aperture masks remind me of the Tripadvisor logo. Can't get it out of my head.

[pat in los angeles basin]

That's how the pusher eventually sells the product- "just a taste". I  have lusted over the AK prismed 7x45  for a while now. Pat

[tmichaelbanks]

I anxiously await your report Mr. Fiske ("Who was that Masked Man?"  ).

 

Under reasonably decent conditions, I was able to see quite a bit in the night sky with my cheapo Pentax AD 8x25s (purchased for kayaking and biking primarily).

 

Specifically, see posts 6, 15, and 16 at https://www.cloudyni...hl= c#8208note=.

 

Your suburban night skies are likely a little bit more light-polluted than mine, but I'm in a white-to-red transition zone nevertheless and was able to see the objects described in the posts.  Granted, they were not nearly as aesthetically pleasing as with higher apertures or magnification, but you can get some stuff done with smaller apertures if you know where to look.

[ECP M42]

... for observing deep sky, ... I anticipate is more or less going to be an exercise in debunking. 

If we want to be precise and honest, debunking is certainly not the right term. Because, if you don't see the same objects with 10x25, the test would tend to indicate that mainly your retinal sensitivity is low and that your site's rating is probably wrong.

 

In any case, if anything, a negative test it may not testify in your favor, but to reinforce the reality, which indicates the actual existence of people with different retinal sensitivities, and who may prefer the use of different binoculars, without losing their fun or their dignity. 

 

   

[Fiske]

If we want to be precise and honest, debunking is certainly not the right term. Because, if you don't see the same objects with 10x25, the test would tend to indicate that mainly your retinal sensitivity is low and that your site's rating is probably wrong.

 

In any case, if anything, a negative test it may not testify in your favor, but to reinforce the reality, which indicates the actual existence of people with different retinal sensitivities, and who may prefer the use of different binoculars, without losing their fun or their dignity. 

 

   

Henry,

 

Anyone who wants to repeat my observations by making 25mm aperture masks and comparing 10x25 and 10x50 views is welcome and even encouraged to do so, and to share their reports here. 

Edited by Fiske, 09 December 2021 - 09:09 PM.

[ECP M42]

Tonight, after answering here, I opened the south window out of curiosity and saw Orion!  
Yesterday it was snowing, today I saw the clearest and darkest sky that I had never seen before.

So I took out the 10x25, the 10x42, the 18x50 and also the 25x70 (which I haven't used for too long). 

 

I had to block out the street light and then I sat down to watch that amazing sight.
I don't remember ever seeing so many stars in Orion, especially in the sword and belt, but maybe my memory is rusty. 

 

At one point, with the 18x50, I aimed at the cluster NGC 1981 - Cr 73. 

 

 

But although I could imagine dozens and dozens of stars in that area, I could only see 8 directly (blue oval). 

 

So, I retried the comparison between the two 10x (25 and 42mm), but with both I could only see 4 stars directly, plus 3 in averted vision (green arrows).
The octave (the one with orange arrow) was invisible with the two 10x. And apart from the difference in overall brightness between the two binoculars, I still needed averted vision to see the 3 stars on the right.
The eighth star is given as 8.05 mag on Stellarium.

 

All the observations I made freehand (even at 25x), but with the 18x50 I used his monopod.

 

The sky was really cool, but with 10x I couldn't get past ~ 7.5 mag (maybe 7.75). 

 

Fiske, what can you say about it? 

Edited by ECP M42, 10 December 2021 - 12:19 AM.

[Fiske]

Here is my first 25 vs 50mm comparative observation report.   With observations made from my suburban driveway on Thursday 9 December 2021. Skies were slightly hazy, but clear. I would put the naked eye limiting magnitude at around 4.30 based on a sighting of Kappa Cassiopeiae (4.19 mag)

 

The instrument used is a Vortex Razor 10x50 UHD. An excellent binocular, and the sharpest 10x50 in my collection. By using the same instrument with and without 25mm aperture masks to make observations, optical quality becomes a mostly neutral factor in the comparisons. The observations are essentially comparing an excellent quality 10x50mm binocular with an excellent quality 10x25 binocular. Given the advantage of masking all but the center of the objectives, it could be argued that the resulting 10x25 binocular provides a better optical quality view than the same instrument at full aperture.

 

Observations made of the 5 day 20 hour moon support this to a certain extent. A slight CA rim seen in the full aperture view was not present in the masked view. Whether this is a consequence of the reduced illumination or the better figure in the center 25% of the objectives I do not know. The views were enjoyable both with and without the masks. At the current phase, the moon is not overly bright from my perspective so masking wasn't an improvement in that regard. The non masked view showed slightly better detail, though the difference was subtle. For example, the rim structure of a small complex of craters just west of Polybius (C,F,P on chart 57 in the Rukl atlas 1st edition) was noticeably more distinct in the unmasked view. My sense from this comparison is that a less extreme mask might be a potential benefit for lunar observation, even with a top quality binocular. Aperture masks of 42mm or even 35mm might be worth trying. Aperture masks in this range might also reduce flaring on Jupiter, for example. The aperture masks did not seem to provide a noticeable benefit improving star image quality for brighter stars, which is quite good overall but somewhat dependent on eye positioning. I did not spend much time evaluating this characteristic, honestly.

 

More can be seen with a 10x25mm binocular in deep sky observing than I had anticipated.  This is not to say that differences between 25 and 50mm are not apparent. But it is understandable that the differences might not be conspicuous to an observer unfamiliar with 10x50 binoculars and possessing limited knowledge of the night sky. Overall, many more faint stars (8-9.5 magnitude range) can be seen with a mounted 10x50 binocular compared to the view with the same instrument masked to 25mm. Hand held, the magnitude limits at either aperture are reduced by say 1.5-2 magnitudes. 

 

M45 / Pleiades

 

The view with the 25mm binocular is pleasing, frankly. But comparing it directly with 50mm aperture it is obvious and undeniable that fainter stars are brighter and more readily seen. Specifics?

 

 

1. 8.77 mag Seen in direct vision at 50mm and quite difficult in averted with 25mm, seen perhaps 20% of the time.

2. 7.78 mag Seen in direct vision at 50mm but in averted at 25mm. seen perhaps 50% of the time.

3. 9.90 mag Seen in averted perhaps 25% of the time at 50mm. Not seen at 25mm.

4. STFA 8 8.26/8.72 54.7". Easily resolved in direct vision at 50mm (and quite fun). Difficult at 25mm. Primary(?) seen readily in averted. Secondary glimpsed 25% of time.

5. S 437 AB,C 8.13/7.70 38.8. Easily resolved in direct vision at 50mm (and quite fun). Somewhat challenging in averted at 25mm. Seen 75% of time.

 

M52 Open Cluster Cassiopeia

Cluster seen faintly in averted as nebulous glow with brightest star in cluster (SAO 20606 / 8.27 mag) readily seen in direct view at 50mm. Cluster not seen at 25mm. SAO 20606 occasionally glimpsed in averted.

 

WZ Cassiopeia / STTA 254

50mm: Double resolved at 50mm red and blue colors distinct. 25mm Primary seen steadily and red color discenable though not as apparent compared with 50mm view. Secondary seen in averted perhaps 50% of the time. Color not apparent. Frankly, I was impressed the secondary could be glimpsed at 25mm. Had not anticipated that. Secondary is 8.30 magnitude.

 

NGC 457 Open Cluster Cassiopeia

Phi Cas and HD 7902 (the owl's eyes) readily seen at both apertures. At 25mm the rest of the cluster appears as a faint nebulosity in averted vision. It is much brighter at 50mm with 6-8 stars resolved in averted vision and additional grainy nebulosity from partially resolved cluster members.

 

Perseus Moving Group

Perhaps 25% additional faint stars seen at 50mm compared with 25mm. 

 

Kemble's Cascade / NGC 1502 / STF 485

The cascade is faint but seen steadily in averted at 50mm. At 25mm some of the stars can be seen in averted but not the entire string. NGC 1502: a faint granularity with a few stars flickering in averted at 50mm. Not seen at 25mm. STF 485 (6.9/6.9 17.7") is slightly challenging but not hard to resolve at 50mm. It is quite difficult to resolve at 25mm. Presumably the issue is the comparatively small (for binoculars) separation. 

 

M37/M36/M38 Auriga

I was able to see all three of these clusters in averted vision at 25mm, which came as a surprise to me.  All three were more easily seen at 50mm, needless to say, and stars were resolved in both M38 and M36 at 50mm that could not be seen at 25mm, but I was nevertheless impressed that the clusters could been seen at all with such a small aperture under suburban skies.

 

STF 764 Auriga

6.38/7.08 25.6" pa 14*

A recent favorite double of mine. Readily seen and fun at both 25 and 50mm aperture.

 

Thank you for reading. 

Edited by Fiske, 10 December 2021 - 01:44 AM.

[MrZoomZoom2017]

Fiske,

 

What an awesome report!  Greatly appreciate your usual outstanding efforts and sharing with all of us .

 

Cheers,

Tim

Edited by MrZoomZoom2017, 10 December 2021 - 01:44 AM.

[Thotmosis]

Here is my first 25 vs 50mm comparative observation report.   With observations made from my suburban driveway on Thursday 9 December 2021. Skies were slightly hazy, but clear. I would put the naked eye limiting magnitude at around 4.30 based on a sighting of Kappa Cassiopeiae (4.19 mag)

 

The instrument used is a Vortex Razor 10x50 UHD. An excellent binocular, and the sharpest 10x50 in my collection. By using the same instrument with and without 25mm aperture masks to make observations, optical quality becomes a mostly neutral factor in the comparisons. The observations are essentially comparing an excellent quality 10x50mm binocular with an excellent quality 10x25 binocular. Given the advantage of masking all but the center of the objectives, it could be argued that the resulting 10x25 binocular provides a better optical quality view than the same instrument at full aperture.

 

Observations made of the 5 day 20 hour moon support this to a certain extent. A slight CA rim seen in the full aperture view was not present in the masked view. Whether this is a consequence of the reduced illumination or the better figure in the center 25% of the objectives I do not know. The views were enjoyable both with and without the masks. At the current phase, the moon is not overly bright from my perspective so masking wasn't an improvement in that regard. The non masked view showed slightly better detail, though the difference was subtle. For example, the rim structure of a small complex of craters just west of Polybius (C,F,P on chart 57 in the Rukl atlas 1st edition) was noticeably more distinct in the unmasked view. My sense from this comparison is that a less extreme mask might be a potential benefit for lunar observation, even with a top quality binocular. Aperture masks of 42mm or even 35mm might be worth trying. Aperture masks in this range might also reduce flaring on Jupiter, for example. The aperture masks did not seem to provide a noticeable benefit improving star image quality for brighter stars, which is quite good overall but somewhat dependent on eye positioning. I did not spend much time evaluating this characteristic, honestly.

 

More can be seen with a 10x25mm binocular in deep sky observing than I had anticipated.  This is not to say that differences between 25 and 50mm are not apparent. But it is understandable that the differences might not be conspicuous to an observer unfamiliar with 10x50 binoculars and possessing limited knowledge of the night sky. Overall, many more faint stars (8-9.5 magnitude range) can be seen with a mounted 10x50 binocular compared to the view with the same instrument masked to 25mm. Hand held, the magnitude limits at either aperture are reduced by say 1.5-2 magnitudes. 

 

M45 / Pleiades

 

The view with the 25mm binocular is pleasing, frankly. But comparing it directly with 50mm aperture it is obvious and undeniable that fainter stars are brighter and more readily seen. Specifics?

 

 

1. 8.77 mag Seen in direct vision at 50mm and quite difficult in averted with 25mm, seen perhaps 20% of the time.

2. 7.78 mag Seen in direct vision at 50mm but in averted at 25mm. seen perhaps 50% of the time.

3. 9.90 mag Seen in averted perhaps 25% of the time at 50mm. Not seen at 25mm.

4. STFA 8 8.26/8.72 54.7". Easily resolved in direct vision at 50mm (and quite fun). Difficult at 25mm. Primary(?) seen readily in averted. Secondary glimpsed 25% of time.

5. S 437 AB,C 8.13/7.70 38.8. Easily resolved in direct vision at 50mm (and quite fun). Somewhat challenging in averted at 25mm. Seen 75% of time.

 

M52 Open Cluster Cassiopeia

Cluster seen faintly in averted as nebulous glow with brightest star in cluster (SAO 20606 / 8.27 mag) readily seen in direct view at 50mm. Cluster not seen at 25mm. SAO 20606 occasionally glimpsed in averted.

 

WZ Cassiopeia / STTA 254

50mm: Double resolved at 50mm red and blue colors distinct. 25mm Primary seen steadily and red color discenable though not as apparent compared with 50mm view. Secondary seen in averted perhaps 50% of the time. Color not apparent. Frankly, I was impressed the secondary could be glimpsed at 25mm. Had not anticipated that. Secondary is 8.30 magnitude.

 

NGC 457 Open Cluster Cassiopeia

Phi Cas and HD 7902 (the owl's eyes) readily seen at both apertures. At 25mm the rest of the cluster appears as a faint nebulosity in averted vision. It is much brighter at 50mm with 6-8 stars resolved in averted vision and additional grainy nebulosity from partially resolved cluster members.

 

Perseus Moving Group

Perhaps 25% additional faint stars seen at 50mm compared with 25mm. 

 

Kemble's Cascade / NGC 1502 / STF 485

The cascade is faint but seen steadily in averted at 50mm. At 25mm some of the stars can be seen in averted but not the entire string. NGC 1502: a faint granularity with a few stars flickering in averted at 50mm. Not seen at 25mm. STF 485 (6.9/6.9 17.7") is slightly challenging but not hard to resolve at 50mm. It is quite difficult to resolve at 25mm. Presumably the issue is the comparatively small (for binoculars) separation. 

 

M37/M36/M38 Auriga

I was able to see all three of these clusters in averted vision at 25mm, which came as a surprise to me.  All three were more easily seen at 50mm, needless to say, and stars were resolved in both M38 and M36 at 50mm that could not be seen at 25mm, but I was nevertheless impressed that the clusters could been seen at all with such a small aperture under suburban skies.

 

STF 764 Auriga

6.38/7.08 25.6" pa 14*

A recent favorite double of mine. Readily seen and fun at both 25 and 50mm aperture.

 

Thank you for reading. 

Very interesting observation report, I really enjoyed reading it. Thanks a lot