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First Galaxy Season with NV

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#1 DanDK

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Posted 13 July 2020 - 03:40 PM

I haven't yet posted much on cloudynights.  I prefer reading the posts of people who know a lot more than I do. But I thought it might be worthwhile to share a bit about my recent experience of night vision with galaxies, even if most of this has been said before.

 

After a lot of informal research, mostly on CN, I took the plunge earlier this year with the Televue afocal system and a new 10" Orion goto dob (recommended by very helpful CN members), which replaced my old Criterion 8" SCT.  Since then I've enjoyed many hours of backyard viewing.

 

I especially enjoy galaxies.  There were differing opinions on this website about NV and galaxies. Some said the benefit is only marginal, or that it just helped with certain types (edge-ons but not face-ons, etc.).  But when I asked for feedback, the generous response from NV enthusiasts convinced me it would really make a difference.   After 3 months of using NV, I can definitely say it has.

 

When I compare regular views with NV, using the same eyepiece, I find that NV makes every type of galaxy brighter and much easier to see.  It may help some more than others, but there's nearly always a distinct improvement.  The larger, brighter ones show far more detail and structure, including spiral arms and dust lanes.  And many others that I could barely see on the best nights, or only wished I could see, are now easy targets.

 

With NV I often see multiple galaxies in the same field of view, something I hadn't experienced before.  I can also see them at much greater distances.  My total "repertoire" of observable galaxies is easily 10X what it used to be.   The same night sky that offered just a few dozen galactic gems is now full of them. 

 

NV is brightest at low powers, but many galaxies are quite small so I've tried using some higher power eyepieces.  If they're not too dim, I can boost the gain a bit and get nice views up to about 100X (using an 11mm eyepiece), definitely brighter views than with the eyepiece alone.  With moderate light pollution (Bortle 4-5) I've found that the unfiltered view is best, which may help with higher power.

 

Astrophotography had always scared me off, but I was surprised at how easy it is to take simple phone pics with NV.  I've taken around 200, mostly galaxies or galaxy groups. They're obviously not high quality astrophotos, and I get some coma and occasional star trails, but they're quick and easy: 1-minute exposures with the "Night Sight" camera option on my Google phone.  They show more detail (and sometimes more galaxies) than visual NV, and you can "zoom in" for a closer look.  Even with goto, I'm not always sure that I'm seeing what I was searching for.  With the phone pics I can capture views and later check Stellarium or other online resources to verify the targets (or to find out what I was really looking at!).

 

Night vision astronomy was a big step up for me. My observing experience and technical know-how were pretty limited.  But the learning curve wasn't too steep, and it's made a huge difference in what I can see and how I feel about the night sky.  Besides galaxies, I've also had pretty spectacular views of star clusters.  Not many nebulae so far, but summer is here and they'll soon be climbing above my tall trees.

 

I attached a few phone pics (with some enlargement): M100+companions, NGC 5746, NGC 3718+3729+Hickson 56 (marked), and Abell 2199.  I marked about 40 galaxies visible in the Abell group.  It still blows my mind that I can step into my back yard and, with a few amazing tools, see vast island universes nearly a half-billion light years away!

Attached Thumbnails

  • M100 + companions.jpg
  • NGC 5746 - 11mm - 96mLY.jpg
  • NGC3718+3729+ Hickson56 (425mLY).jpg
  • NGC  6166, 6158 -  Abell 2199 490mLY.jpg

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#2 Eddgie

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Posted 13 July 2020 - 04:15 PM

Wow!  Well done! Happy to hear that night vision astronomy is living up to the expectations we set for it, and your report was entertaining to read.

 

The effort you put into the pictures though, making all of the galaxies, is quite remarkable and while I am not typically into pictures, preferring to read about eyepiece impressions,  I very much enjoy these pictures because of how you highlighted so many galaxies.

 

I have seen a lot of pictures posted, here, but I think this one takes the prize for the most galaxies ever captured in a single field.

 

Amazing.  

 

Please post more observations and pictures in the future!


Edited by Eddgie, 13 July 2020 - 04:15 PM.

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#3 bobhen

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Posted 14 July 2020 - 06:29 AM

Nice report.

 

Me thinks you will enjoy nebulas (you will definitely need a filter) as much or even more with NV.

 

Bob


Edited by bobhen, 14 July 2020 - 12:37 PM.

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#4 DanDK

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Posted 14 July 2020 - 09:24 AM

Nice report.

 

Me thinks you will enjoy nebulas (you will definitely need a filter) as much or ever more with NV.

 

Bob

Last night Cygnus finally made it over our trees.  I just pointed the scope toward Deneb, not having planned any targets, used the 67 (formerly 55) mm plossl + Ha filter, stumbled onto the Crescent nebula, panned around, and had one amazing view after another. 



#5 bobhen

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Posted 14 July 2020 - 12:45 PM

Last night Cygnus finally made it over our trees.  I just pointed the scope toward Deneb, not having planned any targets, used the 67 (formerly 55) mm plossl + Ha filter, stumbled onto the Crescent nebula, panned around, and had one amazing view after another. 

Not sure if you have any other scopes but something like a 60 -102mm F5 refractor (can even be an achromat) will give you wider field views. The nebula in Cygnus will fill even the widest fields.

 

Bob


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#6 M44

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Posted 14 July 2020 - 02:37 PM

Excellent report! 

 

I second the recommendation for a small refractor. My 90mm refractor is becoming my most used scope at 9x. I like the scale for scanning MW with both long pass and H alpha. 


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#7 dustyc

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Posted 14 July 2020 - 02:51 PM

I find myself liking those afocal shots where the whole field stop is visible. Kinda like a picture frame only round. 

Great shots!


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#8 DanDK

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Posted 14 July 2020 - 05:21 PM

Not sure if you have any other scopes but something like a 60 -102mm F5 refractor (can even be an achromat) will give you wider field views. The nebula in Cygnus will fill even the widest fields.

 

Bob

I just have the new dob and the old SCT.  But maybe some day!



#9 ManuelJ

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Posted 27 July 2020 - 10:08 AM

My experience is exactly the opposite, NV is a loss at galaxies, they gain on thin bright details, but lose extension and contrast.

On the other hand, distant galaxies are much improved. I can reach up to (visual) magnitude 16 with just a 4 inch!

#10 DanDK

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Posted 27 July 2020 - 05:59 PM

My experience is exactly the opposite, NV is a loss at galaxies, they gain on thin bright details, but lose extension and contrast.

On the other hand, distant galaxies are much improved. I can reach up to (visual) magnitude 16 with just a 4 inch!

I've also noticed that some galaxies, or parts of galaxies, are brightened more than others.  If I had great dark skies and a big scope, I might prefer the natural view.   As it is, I'm just happy to be able to see so many so easily.  There's really no comparison to my pre-NV experience.

 

I can't resist going after those at extreme distances that were out of range before NV.  Can't wrap my mind around how far away they are, but it's fun trying!



#11 ManuelJ

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Posted 28 July 2020 - 04:22 AM

I've also noticed that some galaxies, or parts of galaxies, are brightened more than others. If I had great dark skies and a big scope, I might prefer the natural view. As it is, I'm just happy to be able to see so many so easily. There's really no comparison to my pre-NV experience.

I can't resist going after those at extreme distances that were out of range before NV. Can't wrap my mind around how far away they are, but it's fun trying!


Galaxy cores get a very good punch, but usually the outer parts are dimmed and lost in the background. May be because of star population on outer regions.
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#12 Astrojedi

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Posted 28 July 2020 - 11:49 AM

Great report. Unlike nebulae I have found NV to be a mixed bag with galaxies which to me makes sense.

 

First, NV itself cannot improve contrast. It multiplies light from LP as much as the object so filters are needed to improve contrast. Since galaxies are broadband objects it hurts them quite a bit.

 

Second, NV (gen 3) is most sensitive in the longer wavelengths so it responds much better to bright cores. Galaxies with spiral arms really suffer with NV as arms typically have a lot young blue stars.

 

I actually quite enjoyed viewing the Come galaxy cluster from the club’s dark site. There were tiny galaxies everywhere with my Gen 3 WP and 14” F3.5 Dob and a 50mm plossl. The setup was operating at ~f1.8 and I did not use any filters.

 

On the flip side there was barely much improvement over glass on M51. Once I am dark adapted I can usually see quite a lot of detail in the spiral arms as well as the ‘bridge’ between the galaxies with a regular EP. Maybe this will change as I get older.


Edited by Astrojedi, 28 July 2020 - 11:49 AM.

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#13 DanDK

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Posted 28 July 2020 - 01:25 PM

Great report. Unlike nebulae I have found NV to be a mixed bag with galaxies which to me makes sense.

 

First, NV itself cannot improve contrast. It multiplies light from LP as much as the object so filters are needed to improve contrast. Since galaxies are broadband objects it hurts them quite a bit.

 

Second, NV (gen 3) is most sensitive in the longer wavelengths so it responds much better to bright cores. Galaxies with spiral arms really suffer with NV as arms typically have a lot young blue stars.

 

I actually quite enjoyed viewing the Come galaxy cluster from the club’s dark site. There were tiny galaxies everywhere with my Gen 3 WP and 14” F3.5 Dob and a 50mm plossl. The setup was operating at ~f1.8 and I did not use any filters.

 

On the flip side there was barely much improvement over glass on M51. Once I am dark adapted I can usually see quite a lot of detail in the spiral arms as well as the ‘bridge’ between the galaxies with a regular EP. Maybe this will change as I get older.

I'm already older, so any light boost is good!   

 

Last week I checked out M 101.  Sky was moonless but a bit murky.  With NV and the 27 mm eyepiece I saw no spiral arms, just the core, even in the phone pic.  They showed up, quite tiny, when I used the 67mm.  Without the NV I couldn't see much of anything.

 

Last spring, under better skies and closer to zenith, they were easier to see and photograph. 


Edited by DanDK, 28 July 2020 - 02:37 PM.


#14 bobhen

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Posted 28 July 2020 - 04:09 PM

Compared to regular glass I found that NV increased the brightness of all galaxies and makes them easier to see/observe.

 

In mild and heavy light pollution galaxies really suffer using regular glass but do not suffer in the same conditions using NV. Why, because you can increase the contrast by using a Pass filter. You cannot use such a filter with regular glass, because the filter is too strong. So you can get both a light gathering boost AND a contrast boost with NV that is just unavailable with regular glass.

 

Of course some galaxies are better observed than others but that is also true with glass.

 

just one example: With my light pollution I was never able to see galaxy 891, even with a 15” Dobsonian. But I can spot that galaxy with my “small” 120mm refractor and NV.

 

Last spring I used my C-8 and NV to observer 47 galaxies (of all types) in one session, and all from a Bortle 7.5-8 location just outside Philadelphia. Many I had not observed before in 31 years observing from this location using regular glass and telescopes as large as a C11 and a 15” Dobsonian.

 

NV does not compare to EAA, astro-video or short exposure CCD images for the detail you can get on galaxies using those “camera” technologies but when compared to regular glass, NV does make galaxies easier to spot and observe and also makes some invisible galaxies visible.

 

Bob


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#15 Jeff Morgan

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Posted 28 July 2020 - 11:53 PM

Great report. Unlike nebulae I have found NV to be a mixed bag with galaxies which to me makes sense.

 

First, NV itself cannot improve contrast. It multiplies light from LP as much as the object so filters are needed to improve contrast. Since galaxies are broadband objects it hurts them quite a bit.

 

Second, NV (gen 3) is most sensitive in the longer wavelengths so it responds much better to bright cores. Galaxies with spiral arms really suffer with NV as arms typically have a lot young blue stars.

 

I actually quite enjoyed viewing the Come galaxy cluster from the club’s dark site. There were tiny galaxies everywhere with my Gen 3 WP and 14” F3.5 Dob and a 50mm plossl. The setup was operating at ~f1.8 and I did not use any filters.

 

On the flip side there was barely much improvement over glass on M51. Once I am dark adapted I can usually see quite a lot of detail in the spiral arms as well as the ‘bridge’ between the galaxies with a regular EP. Maybe this will change as I get older.

 

Performance is definitely more nuanced - and not as dramatic as intra-galactic objects.

 

As you point out, no filter to isolate them as we have for nebula. So from light polluted sites, gain is not as dramatic.

 

But there is gain. Compared to a conventional eyepiece of focal length in the 20's, no contest at all. NV wins hands down on core and spiral arms.

 

The big advantage of conventional is the ability to run up the power. The eye does not care at all about focal ratio, whereas NV cares quite a bit.

 

Thus far, most of my galaxy observing has been from home - SQM 20.5, yellow zone light pollution. I have found a new site that is a full magnitude better. This fall it will be interesting to see how galaxy arms present there.


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#16 hoof

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Posted 29 July 2020 - 03:56 PM

Galaxy cores get a very good punch, but usually the outer parts are dimmed and lost in the background. May be because of star population on outer regions.

This is expected.  Cores tend to be more on the red side of things (thus the eye doesn't see them as well as our eye's red night vision is poor), while the arms tend to be blue-er (which the eyes pick up very well, but night vision doesn't).

 

That said, except for the really blue arm details, the NV tends to show galaxies in a more "correct" brightness distribution, as cores are in reality much brighter than arms/outer sections.  It's our eye's night vision color response that mutes the cores making the difference between outer and inner galaxy brightness much less noticeable visually.


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#17 The Ardent

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Posted 29 July 2020 - 04:28 PM

Had a good night recently- viewed UGC 11368 and 11370 in Lyra. The latter only visible with NV. These are also likely obscured by the plane of the Milky Way.

Years ago I was able to observe Maffei I and II from my city backyard with NV.

#18 DanDK

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Posted 29 July 2020 - 04:40 PM

Had a good night recently- viewed UGC 11368 and 11370 in Lyra. The latter only visible with NV. These are also likely obscured by the plane of the Milky Way.

Years ago I was able to observe Maffei I and II from my city backyard with NV.

How big is your scope?  Those are really faint.  



#19 Peregrinatum

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Posted 29 July 2020 - 06:33 PM

I haven't yet posted much on cloudynights.  I prefer reading the posts of people who know a lot more than I do. But I thought it might be worthwhile to share a bit about my recent experience of night vision with galaxies, even if most of this has been said before.

 

After a lot of informal research, mostly on CN, I took the plunge earlier this year with the Televue afocal system and a new 10" Orion goto dob (recommended by very helpful CN members), which replaced my old Criterion 8" SCT.  Since then I've enjoyed many hours of backyard viewing.

 

I especially enjoy galaxies.  There were differing opinions on this website about NV and galaxies. Some said the benefit is only marginal, or that it just helped with certain types (edge-ons but not face-ons, etc.).  But when I asked for feedback, the generous response from NV enthusiasts convinced me it would really make a difference.   After 3 months of using NV, I can definitely say it has.

 

When I compare regular views with NV, using the same eyepiece, I find that NV makes every type of galaxy brighter and much easier to see.  It may help some more than others, but there's nearly always a distinct improvement.  The larger, brighter ones show far more detail and structure, including spiral arms and dust lanes.  And many others that I could barely see on the best nights, or only wished I could see, are now easy targets.

 

With NV I often see multiple galaxies in the same field of view, something I hadn't experienced before.  I can also see them at much greater distances.  My total "repertoire" of observable galaxies is easily 10X what it used to be.   The same night sky that offered just a few dozen galactic gems is now full of them. 

 

NV is brightest at low powers, but many galaxies are quite small so I've tried using some higher power eyepieces.  If they're not too dim, I can boost the gain a bit and get nice views up to about 100X (using an 11mm eyepiece), definitely brighter views than with the eyepiece alone.  With moderate light pollution (Bortle 4-5) I've found that the unfiltered view is best, which may help with higher power.

 

Astrophotography had always scared me off, but I was surprised at how easy it is to take simple phone pics with NV.  I've taken around 200, mostly galaxies or galaxy groups. They're obviously not high quality astrophotos, and I get some coma and occasional star trails, but they're quick and easy: 1-minute exposures with the "Night Sight" camera option on my Google phone.  They show more detail (and sometimes more galaxies) than visual NV, and you can "zoom in" for a closer look.  Even with goto, I'm not always sure that I'm seeing what I was searching for.  With the phone pics I can capture views and later check Stellarium or other online resources to verify the targets (or to find out what I was really looking at!).

 

Night vision astronomy was a big step up for me. My observing experience and technical know-how were pretty limited.  But the learning curve wasn't too steep, and it's made a huge difference in what I can see and how I feel about the night sky.  Besides galaxies, I've also had pretty spectacular views of star clusters.  Not many nebulae so far, but summer is here and they'll soon be climbing above my tall trees.

 

I attached a few phone pics (with some enlargement): M100+companions, NGC 5746, NGC 3718+3729+Hickson 56 (marked), and Abell 2199.  I marked about 40 galaxies visible in the Abell group.  It still blows my mind that I can step into my back yard and, with a few amazing tools, see vast island universes nearly a half-billion light years away!

 

Great report!  Curious if you are holding the phone to the eyepiece or using some type of phone mount to the NV eyepiece?
 


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#20 DanDK

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Posted 29 July 2020 - 07:29 PM

Great report!  Curious if you are holding the phone to the eyepiece or using some type of phone mount to the NV eyepiece?
 

Televue makes a FoneMate and adapter which attaches securely to the NV monocular.   It's a bit tricky for me to keep the phone properly aligned, but otherwise works well:

 

http://www.televue.c..._page.asp?id=36


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#21 ManuelJ

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Posted 30 July 2020 - 02:36 AM

Performance is definitely more nuanced - and not as dramatic as intra-galactic objects.

 

As you point out, no filter to isolate them as we have for nebula. So from light polluted sites, gain is not as dramatic.

 

But there is gain. Compared to a conventional eyepiece of focal length in the 20's, no contest at all. NV wins hands down on core and spiral arms.

 

The big advantage of conventional is the ability to run up the power. The eye does not care at all about focal ratio, whereas NV cares quite a bit.

 

Thus far, most of my galaxy observing has been from home - SQM 20.5, yellow zone light pollution. I have found a new site that is a full magnitude better. This fall it will be interesting to see how galaxy arms present there.

That is not true for me. Comparing for example a 17 Ethos with F/4 night vision:

 

M101: With Ethos contrast and galaxy extension, as well as spiral arms are in another league. Eyepiece wins hands down.

 

M51: NV makes some parts of the spiral arms more defined, but arms extension is highly impacted.

 

M31: Super bright core and well defined (and textured) dark bands, stars on NGC 206 are easily resolved (20-30 members), but the galaxy is lost in the background, while on visual it is very bright.

 

 

So far I've not seen anything with NV on galaxies that can't be seen with conventional eyepieces, but I can usually see more with glass. Globular and open clusters, on the other hand, are always a win.


Edited by ManuelJ, 30 July 2020 - 02:37 AM.

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#22 bobhen

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Posted 30 July 2020 - 06:52 AM

That is not true for me. Comparing for example a 17 Ethos with F/4 night vision:

 

M101: With Ethos contrast and galaxy extension, as well as spiral arms are in another league. Eyepiece wins hands down.

 

M51: NV makes some parts of the spiral arms more defined, but arms extension is highly impacted.

 

M31: Super bright core and well defined (and textured) dark bands, stars on NGC 206 are easily resolved (20-30 members), but the galaxy is lost in the background, while on visual it is very bright.

 

 

So far I've not seen anything with NV on galaxies that can't be seen with conventional eyepieces, but I can usually see more with glass. Globular and open clusters, on the other hand, are always a win.

That is not my experience. When you observe galaxies with NV are you using a Pass filter like a Baader 610 or 685?

 

NV multiplies photons. An Ethos eyepiece does not. If there is any light pollution in the sky, you need to filter that out when using NV - even for non-nebula objects.

 

I observe from a Bortle 8 location outside Philadelphia, PA and using NV all galaxies are enhanced.

 

Examples….
891: never seen in my C11. Spotted with my 4” refractor using NV
3628: Most nights not spotted using my C11: once or twice 891 was observed as a very dim glow with telescope motion. Spotted easily with my 4” refractor using NV
M51: Only the cores were seen in my C11. Hazy arms are easily seen with my 120mm refractor and C8 using NV and some faint knotty detail is seen in the arm on good nights with NV

 

And of course there are some galaxies that were never spotted or were spotted with much difficulty using glass that are now visible or spotted much easier with NV – and while using SMALLER telescopes.

 

Bob


Edited by bobhen, 30 July 2020 - 06:53 AM.

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#23 ManuelJ

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Posted 30 July 2020 - 10:27 AM

That is not my experience. When you observe galaxies with NV are you using a Pass filter like a Baader 610 or 685?

NV multiplies photons. An Ethos eyepiece does not. If there is any light pollution in the sky, you need to filter that out when using NV - even for non-nebula objects.

I observe from a Bortle 8 location outside Philadelphia, PA and using NV all galaxies are enhanced.

Examples….
891: never seen in my C11. Spotted with my 4” refractor using NV
3628: Most nights not spotted using my C11: once or twice 891 was observed as a very dim glow with telescope motion. Spotted easily with my 4” refractor using NV
M51: Only the cores were seen in my C11. Hazy arms are easily seen with my 120mm refractor and C8 using NV and some faint knotty detail is seen in the arm on good nights with NV

And of course there are some galaxies that were never spotted or were spotted with much difficulty using glass that are now visible or spotted much easier with NV – and while using SMALLER telescopes.

Bob


On bortle 2-3 that gain does not exist. I'm not using IR filters, maybe that's the problem.

#24 bobhen

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Posted 30 July 2020 - 10:59 AM

On bortle 2-3 that gain does not exist. I'm not using IR filters, maybe that's the problem.

Try the filters. An image intensifier multiplies ALL light – even unwanted light pollution – and even very mild light pollution will be multiplied.

 

Bob



#25 Jeff Morgan

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Posted 30 July 2020 - 12:01 PM

That is not true for me. Comparing for example a 17 Ethos with F/4 night vision:

 

Exactly my point: 17mm eyepiece vs. 27mm eyepiece. You need higher magnification on the conventional side. I've compared a 26 Plossl and 27 Panoptic extensively to my NV eyepiece. At 27mm NV wins every time - cores, arms, dust lanes - because of the intensification.

 

I must confess here that galaxies are not my forté - I much prefer intra-galactic targets, and always have over the decades.

 

Almost all of my galaxy observations (500+ logged with the image intensifier) have been from my suburban setting, SQM 20.5, "yellow zone" on the light pollution maps. I suspect that from better skies (SQM 21.5) the intensifier will do better on galaxies than shorter eyepieces since there is more signal (galaxy) and less noise (light pollution). NV does not discriminate (much), it boosts all of the incoming light.

 

Really, what we are comparing are sensors - the GaAs vs. the retina in terms of brightness and response.

 

When you run up the magnification on the intensifier, you reduce the speed and hence the brightness. The eye OTOH is not sensitive to speed. Running up the magnification has little penalty, but the benefit of getting more retinal cells involved.

 

 

And of course the spectrum of galaxies (particularly blue shifted arms) and the response of the eye vs. the intensifier, this explains it quite well:

 

http://www.ceoptics....ech_report.html


Edited by Jeff Morgan, 30 July 2020 - 12:05 PM.

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