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NV might be sensitive, but the color is so...bland.

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#1 Stargazer3236

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Posted 13 December 2018 - 11:22 PM

I have been looking at some NV images in this forum. The sensitivity is nice, but the color is just so...yechhhh. I prefer a faint, CMOS camera image than an NV image. It is just so grainy and so...green.

 

White phosphorous is nice and better looking than NV Green. But I like my color images better.

 

Just my 2 cents.


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#2 Tyson M

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Posted 13 December 2018 - 11:35 PM

In this hobby, each piece of equipment design has its advantages and disadvantages. The saying "There is no free lunch" holds true here. 

 

From telescope and eyepiece designs, specialty eyepieces and filters, night vision, cameras ect.  Different tools for different tasks, some better in certain areas than others.  That's why we spend so much money lol, and why forums like this are popular and exist. 


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#3 bobito

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Posted 13 December 2018 - 11:49 PM

Plus with EAA you can WiFi your camera then Chromecast to your TV and view from your couch!



#4 The Ardent

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Posted 13 December 2018 - 11:56 PM

I'm looking into EAA cameras for color live viewing with the option of taking a pic. Which camera is best?

Nothing I've seen shows the real time sensitivity of NV without stacking or long exposure.


please direct me to a ranking of all the current EAA camera by sensitivity, with NV as comparison.

Thanks
Ray

name="Stargazer3236" post="9008123" timestamp="1544761352"]
I have been looking at some NV images in this forum. The sensitivity is nice, but the color is just so...yechhhh. I prefer a faint, CMOS camera image than an NV image. It is just so grainy and so...green.
 
White phosphorous is nice and better looking than NV Green. But I like my color images better.
 
Just my 2 cents.



#5 TOMDEY

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Posted 14 December 2018 - 12:25 AM

I have been looking at some NV images in this forum. The sensitivity is nice, but the color is just so...yechhhh. I prefer a faint, CMOS camera image than an NV image. It is just so grainy and so...green.

White phosphorous is nice and better looking than NV Green. But I like my color images better.

Just my 2 cents.

In this hobby, each piece of equipment design has its advantages and disadvantages. The saying "There is no free lunch" holds true here. 

From telescope and eyepiece designs, specialty eyepieces and filters, night vision, cameras ect.  Different tools for different tasks, some better in certain areas than others.  That's why we spend so much money lol, and why forums like this are popular and exist. 

Both are valid observations, of course. Once sensors approach QE of unity (now-a-days true of high-end CCD, CMOS, Night Vision...) the No Free Lunch invariant kicks in. You are availing nearly all the information throughput your aperture can suck in... all that's left is how it is presented [and/or more aperture].

 

And That means balancing the niceties. Stargazer laments grainy monochrome... therefore must sacrifice display refresh rate, luminance and limiting magnitude to enjoy the faint, smooth, color image. Me, I want to comfortably examine the most remote globulars, real time, so Night Vision on a 36-inch scope does the trick. Someone doing spectroscopy would configure differently.

 

Actually, it's Wonderfully-Decadent, that we can whine over being dissatisfied with not having it all... all of the time.  Mother Nature keeps our tantrums in-line, by limiting the flow-rate of information from the heavens.

 

Galileo, Newton, Rosse, Herschels, Hale, Porter, Hubble... would all envy us the equipment that we can just buy, off-the-shelf tonight.

 

Occasionally worth taking a deep breath and counting our blessings!  Tom


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#6 t_image

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Posted 14 December 2018 - 01:01 AM

I'm looking into EAA cameras for color live viewing with the option of taking a pic. Which camera is best?

Nothing I've seen shows the real time sensitivity of NV without stacking or long exposure.


please direct me to a ranking of all the current EAA camera by sensitivity, with NV as comparison.

Thanks
Ray

Here, I'll start by analyzing some basic videos of what REALTIME cameras can do at best:

*which is a degree less than IINV can do.......

given the optics are f/1.4 or better for such effect:

 

1. Canon MH20H-SH

price: $20,000 USD

1080HD max

not capable of stills, video only
https://vimeo.com/180637962

 

2. Sony a7s
price: $2500 USD
up to 4K resolution
interchangeable lenses
can take stills

realtime
just less than 30fps:
https://www.youtube....h?v=xNUyLIbI3l8

30fps legit:
https://www.youtube....c5_i7M#t=12m15s

 

(hard to tell without legit sky examples:)
3. X27 Osprey
price:(good luck trying to purchase)
up to 1080HD
interchangeable lenses

https://www.x20.org/...r-night-vision/
https://www.youtube....h?v=Z7oX1_5HOPI

 

4. SiOnyx Aurora

price: $600 USD
auto mode only
720P max
can take stills

15fps:
https://www.youtube....h?v=jmxrKr1Zno0

 

Again, the performance must show realtime motion. No stacking or frame integration slower than 15fps need apply...

 

Cheers!


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#7 chemisted

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Posted 14 December 2018 - 06:03 AM

I have been looking at some NV images in this forum. The sensitivity is nice, but the color is just so...yechhhh. I prefer a faint, CMOS camera image than an NV image. It is just so grainy and so...green.

 

White phosphorous is nice and better looking than NV Green. But I like my color images better.

 

Just my 2 cents.

I have to ask: Have you ever spent any time at a telescope looking at objects with a P43 phosphor image intensifier eyepiece?  Within minutes the brain no longer sees the green hue at all - it converts to grey scale just as if you were using a normal eyepiece.  The amount of scintillation that occurs depends on the telescope and sky conditions but normally is quite minimal and also gets tuned out as you get totally excited by the amazing sight you are enjoying in real time.


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#8 Eddgie

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Posted 14 December 2018 - 09:14 AM

Sounds like NV is not for you then.  Yes, it is monochromatic, but it is real time with no monitors or integration time.

 

But that is not for everyone.

 

Some only think proper astronomy is using a glass eyepiece.  I get that too, and neither NV and EAA would fit their own preferences.

 

Your observations are valid though, and you won't hear me saying otherwise.  Everything in astronomy involves compromise. 


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#9 bikerdib

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Posted 14 December 2018 - 04:27 PM

Don't take this the wrong way, I'm asking a question not making a comment.  I haven't see a lot, but the few pictures using NV that I have seen don't seem to show a lot of detail.  Is it lack of resolution of the sensor?  The pics I've seen look sort of, for lack of a better term, blurry.  I use my ASI294 for NRTV on occasion but I'm about 90% to 95% visual.

 

Is the NV live view as sharp as looking through a good quality eyepiece?  I'm not talking about the color but the quality/resolution of the image.



#10 Eddgie

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Posted 14 December 2018 - 05:07 PM

The resolution of the device is 64 line pair per millimeter, so over an 18mm circle, it can resolve (18 x 64) 1152 line pair, or (x2) 2304 individual lines.

 

Now as a comparison, the Alienware Gaming Computer I am typing this on can only show 1920 lines so the tube has a maximum resolution that is greater than a great many computers.

 

Now in terms or how this matches up to the human eye, the resolution would be on the order of 1.6 arc minutes of the eyepiece field of view.  People would say "Hey Ed, the Human Eye can resolve 1 arc minute (the actual figure from tests is about 1.1 arc minute, but let's not quibble). 

 

Yes, the photopic eye can resolve about 1 arc minute, but the scotopic eye (dark adapted eye) can only resolve about 3 arc minutes of detail, and on dim scenes with NV, the eye is working more in the mesopic mode, so the 1.6 arc minute resolution is about perfectly matched to the resolution of the mesopic eye.  This is not by chance.  This is the third generation of US Military night vision technology, and the 64 line pair per millimeter standard was considered to be the maximum the operator needed to see all of the detail possible in a low light scene.    That is why the resolution requirement for military tubes remains 64 line pair per millimeter. (In very bright scenes like semi urban, higher can be used because here there is almost always enough ambient light so that the operator's eye at the tube is working in full photopic mode.  For law enforcement where the ambient light is often more than near pitch black, this is useful and I think LE started using 72 line pair tubes a while back).  

 

Now there is noise and this noise can interfere with the observer's ability to perceive faint and find detail, but the chances of seeing that detail are often many times greater than one would have un-aided.

 

But you are correct in that when using heavy filters, the view can be noisy.  Most people using NV will tell you that it was a big concern for them, but my bet is that most people would say that after using it, they found the noise to have far less of an impact than they would have thought. 

When using mild long pass filters for galaxies, the noise on bight galaxies is minimal.

 

That being said, the view does have noise, but it is quite sharp and it is possible to see detail directly that would otherwise require some amount of exposure time to see.

 

It is a compromise.  It lets people see what they would not be able to see and in a very simplified way because it is used i in the same way that any other eyepeice is used.   There are no power cords, tables, laptops, cables, software, or anthing else to get in the way of observing.   The cost is a view that while very sharp, can indeed be noisy. 

 

NV Is though not for everyone.  At least one person on the forums looked though a NV device at a star party and he hated it, and told us all that he hated it.  And some might.   But most using it are very pleased with it.

Again, a compromise.  My observing feels as natural as it always has (put eyepiece in focuser, look into eyepiece, see object) but the view is not like a picture. I accept that because it allows me to see far more than I used to, but I am always very clear to say that in many dim scenes, the view can be noisy and I do think that this would bother most people.  

 

I like the green. I think my eye has an easier time pulling out faint nebula because well, mesopic eye is more sensitive to green than the multi-frequency light of the WP tubes.  I have both, and over the last two years, I have drifted back to green as my preferred color, but I don't find the color to be offensive, and in fact, the eye almost treats it as monochromatic.  If I don't "look" for the green, I don't see it.  I see the structure of the object I am looking at more than I see the color of the object I am looking at.   But not everyone likes the green, but I have grown to prefer it. 

 

Not for everyone though.   I would recommend it for people that don't want to do imaging or classic EAA and would prefer to just observe as they normally would.  Most like it, but there are some that would not and because the cost is high, I tell people that if they really think the noise would bother them, it is too big a risk to take because it actually might bother them, and then they have an expensive piece of kit that they have to sell, perhaps taking a meaningful loss. 


Edited by Eddgie, 14 December 2018 - 05:07 PM.

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#11 Eddgie

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Posted 14 December 2018 - 05:15 PM

And again, the common notion that the view lacks sharpness, contrast, and dynamic range comes almost always from people that have never actually looked though a device.  Computer monitors can't really capture the dynamic range that the computer can show.  When I view images of Orion Nebula, the core is often washed out, but in NV, it is strickingly rich and detailed area of the nebula.   I think I get a better view of the core around the Trap than is shown in a big percentage of images, which tend to wash out the core. At the eyepiece, the core of Orion Nebula is magnificent. 


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#12 Jeff Morgan

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Posted 14 December 2018 - 07:22 PM

I have been looking at some NV images in this forum. The sensitivity is nice, but the color is just so...yechhhh. I prefer a faint, CMOS camera image than an NV image. It is just so grainy and so...green.

 

White phosphorous is nice and better looking than NV Green. But I like my color images better.

 

Just my 2 cents.

 

Totally different imaging techniques.

 

CMOS is like a professional portrait. Excellent purpose-made camera, well (and long) composed, and whatever post-processing is needed for the perfect image. And of course, it is time-intensive and has a steep learning curve with many failure points.

 

Cell phone photography is like snapshots at the beach. Spur of the moment, non-dedicated camera (it's your phone), sensor not made for low light conditions. Very casual. No post-processing. And anyone that can hold a camera still for a few seconds (or afford a cell phone adapter) can do this.

 

I have been thinking a little bit about looking at the ZWO offerings and see if any of them would be suitable for afocal use. It's a slippery slope ...

 

As you have concluded all of you CMOS guys are safe. No full-page NV cell phone images will be appearing in the magazines anytime soon.

 

The real take-away from NV cell phone imagery is that compared to a glass eyepiece, the intensifier can make DSO's bright enough to use a daylight camera. That's pretty amazing by itself.


Edited by Jeff Morgan, 14 December 2018 - 07:27 PM.

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#13 Eddgie

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Posted 14 December 2018 - 07:36 PM

Yeah, I don't see NV as a competitor to any kind of camera.  I myself am not really interested in taking and storing images. I just prefer to look and see what I an see.  The vast majority of my use is just using it as an eyepiece.  I dislike imaging of almost any kind simply because it distracts me from what I really enjoy doing, which is just looking through the telescope to see what I an see. 

 

It has made it possible for me to see things from my red zone sky that I have have struggled the previous 30 years to see at all from any location I have been too. You won't find me complaining about the color or the noise because without it, I would not have been able to complete my bucket list and see all of the absolutely amazing things I have seen since then. I accept the noise and the monochrome view as a very small compromise for the giant gain in my observation capability. 


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#14 Antares89

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Posted 14 December 2018 - 08:57 PM

Galileo, Newton, Rosse, Herschels, Hale, Porter, Hubble... would all envy us the equipment that we can just buy, off-the-shelf tonight.


And I envy their dark skies

#15 bikerdib

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Posted 14 December 2018 - 10:30 PM

OK, so does NV work sort of like NRTV in that a large OTA isn't really needed?  I use my 80mm and sometimes my 152mm on those occasions when I want to do NRTV.  Is there a cut off point of sorts where the view through a larger OTA is equal to the NV view?  For instance, the detail I see of the above discussed Orion nebula with my 14" Edge or my 16" DOB combined with an O-III filter or the DGM MPB is stunning in detail.



#16 TOMDEY

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Posted 15 December 2018 - 04:34 AM

Don't take this the wrong way, I'm asking a question not making a comment.  I haven't see a lot, but the few pictures using NV that I have seen don't seem to show a lot of detail.  Is it lack of resolution of the sensor?  The pics I've seen look sort of, for lack of a better term, blurry.  I use my ASI294 for NRTV on occasion but I'm about 90% to 95% visual.

Is the NV live view as sharp as looking through a good quality eyepiece?  I'm not talking about the color but the quality/resolution of the image.

OK, so does NV work sort of like NRTV in that a large OTA isn't really needed?  I use my 80mm and sometimes my 152mm on those occasions when I want to do NRTV.  Is there a cut off point of sorts where the view through a larger OTA is equal to the NV view?  For instance, the detail I see of the above discussed Orion nebula with my 14" Edge or my 16" DOB combined with an O-III filter or the DGM MPB is stunning in detail.

That's where the invariant I mentioned kicks in: To "fairly" compare sensor technologies, you need to apply them using the same aperture, array area, and integration times. You will then find that they all come out about equal... different renditions, but equal information content. What is invariant is this product:

 

potentially-available information = K x aperture area x sensor area x QE x spectral bandwidth x integration time

 

where the constant K is the same, across all current and future technologies, consequent/obeying Emmy Noether's Theorem!  And That's quite profound!  It is the "No Free Lunch" consul, expressed as an iron-clad requirement, imposed by Mother Nature.

 

It is the greatest upper bound to what we can hope to achieve, across all theories, approaches and technologies... past, present and future.

 

BIT MORE WONK: We find Emmy Noether's Theorem appearing is myriad forms/names/guises: Lagrange Invariant, étendue, radiance theorem, luminance theorem, information theory, uncertainty principle (where K comes from), real ray-trace, paraparaxial ray-trace, photon shot noise, Abbe sine-condition, Airy/Jacobian formulae, passive non-imaging energy concentrator bound... It's all over the place!  Tom



#17 PEterW

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Posted 15 December 2018 - 05:35 AM

Dialling the gain down on modern high res NV gives an image you would have trouble identifying as NV. Scope aperture is not the key, focal ratio is, to fast. Changing the focal length then just changes the image scale for an image of the same brightness. I’d love to understand the length of ccd/cmos exposure I’d need to match the view on a given optic. With NV it’s easy to swing round the sky in real-time and see how things fit together. With more NV being used I hope more people get to witness it firsthand.

Peter
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#18 Eddgie

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Posted 15 December 2018 - 09:18 AM

OK, so does NV work sort of like NRTV in that a large OTA isn't really needed?  I use my 80mm and sometimes my 152mm on those occasions when I want to do NRTV.  Is there a cut off point of sorts where the view through a larger OTA is equal to the NV view?  For instance, the detail I see of the above discussed Orion nebula with my 14" Edge or my 16" DOB combined with an O-III filter or the DGM MPB is stunning in detail.

I am sorry but I don't know what NRTV stands for. Something like Near Real Time View?

 

While you can use NV to image, when used at the eyepiece, the view is not "Near Real Time." it is real time. (Though you can image with it if you like as well, and get very good results with very short exposures, but not in color). 

 

I look in and I see a view.  There is no integration time or anything.  If I move the scope, the view instantly changes and there is no straking or fading of the view.  It behaves just like an eyepiece.

 

NV Is best used with faster instruments but typically, NV will give results on stars that is easily equivalent to doubling the aperture.   A 6" scope used with NV will show stars of limiting magnitude that a 12" scope would be needed to show when using glass eyepieces. Some say more and they may be right but it depends on a lot of factors, so I tend to be conservative, but I have seen well over 2 magnitude gain many times, so doubling should be considered as a reasonable minimum expectation, but I have seen Mag 17.8 stars using my 12" dob from the city. In real time...

 

Galaxies will vary a bit, but in my own experience, I think a doubling of aperture is minimum.  I can see very faint galaxies from my red zone that escaped me using any size telescope I had used prior to NV.  Even my 6" shows more galaxies than I could get from my C14 under similar skies, and my 6" does better than the C14 did under Bortle 5.   Some of that though is because my 6" is f/2.8.  NV Devices work best with fast instruments.   With an 80mm f/6 refractor though, under Bortle 2 skies, I had fields of view that had many galaxies in view at the same time.   Crazy.   Oh, the galaxies were tiny tiny tiny at 20x, but still resolvable as galaxies.

 

I can see the Whirlpool with comanion and with spiral arms in real time from my red zone sky.  Takes a pretty clear and dry night to see it well, but that is not a specific to NV condition.  It happens with cameras and with regular eyepieces.  Some nights are worse than others, some better.  

 

Using Peter's 16" f/4.5, we have seen dark lanes in the Rosette from Bortel 5 skies.   So, no limit on the size scope you can use them in.

 

On nebula, the difference is profound.  I doubt that it would be easy to see some of the nebula I can see from the city even using all but the largest amateur scopes under very dark skies.

 

Did you know that M29 is inside of a nebula?  I can this nebula on a good, clear night from my Red zone sky.  I can see that in real time.

 

The Pillars of Creation in the Eagle Nebula?  I can see that in my 12" Dob from my red zone skies.. I can see it in real time.  Is there some noise? Yes.   Does it bother me?  Well, I was so excited the first time that I saw the Pillars of Creation, I have to tell you that it was one of the great moments of the 35 years I have been observing, and I did not even think about the noise.

 

I see nebula all over the sky.  At 1x, under dark skies, the amount of giant nebula is unreal.   There are nebula out there so big that they are hardly ever imaged by amateurs. 

 

Reflection nebula do not show well in NV.  Too blue.   

 

And of course, you don't see star colors or the color visible in some planetary nebula.

As has been pointed out by others in the past though, NV is not an either/or propostion. Because it can be used exactly like an eyepiece, if you want to see color, do what you do when using conventional eyepieces, which is simply to swap it out.  If you think the view of a double star would be better in a glass eyepiece, you pull the NV device out and put in another eyepiece!  It is not mutually exclusive.  Using NV is just like using any other eyepiece.  If it is not the right eyepiece for the subject, you simply change eyepieces!

 

Still, it is not for everyone.   When running heavy filters on faint nebula, the view can be noisy, but you can see things that you would not otherwise see, and you can see them in real time.  

 

It is the real time aspect of it that most appeals to me.  It is just an eyepiece, but one that greatly enhances the performance of a telescope.

 

Faster scopes work better than slower scopes, but with afocal projection, you can turn an f/15 scope into an f/7.5 scope just by using a 55mm Plossl.   A 12" f/5 scope would become a 12" f/2.5 scope using afocal projection with a 55mm Plossl (and I don't know why EAA people are not using afocal projection more.  It might work better than using focal reducers in some cases).   Now I don't usually use afocal, preferring to work at prime focus, but I can use it if I like because it does not take any expensive special equipment (other than the NV device of course).


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#19 DMala

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Posted 15 December 2018 - 10:11 AM

Case point: this is all it takes to have fun observing at my main residence, where between light pollution and very limited unobstructed sky views, in most cases there isn't much I can see with just visual astronomy. And yes, even the (military surplus) case is green! wink.gif

 

Obviously I could see more and better with much more complex equipment, but simplicity is what I need the most.

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#20 bobhen

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Posted 15 December 2018 - 10:16 AM

OK, so does NV work sort of like NRTV in that a large OTA isn't really needed?  I use my 80mm and sometimes my 152mm on those occasions when I want to do NRTV.  Is there a cut off point of sorts where the view through a larger OTA is equal to the NV view?  For instance, the detail I see of the above discussed Orion nebula with my 14" Edge or my 16" DOB combined with an O-III filter or the DGM MPB is stunning in detail.

Using Night Vision will increase the light gathering potential of any scope of any size. So no matter what size scope you use, light gathering will be improved using NV. You will see (visually and in real time) more detail in M42 using your 14", or any scope, with NV than without. 

 

However, there is another HUGE advantage to NV. Not only do you get increased light gathering but because NV is so powerful you can now use really strong photographic filters that dramatically increase contrast. And deep sky observing is not just about light gathering but it is also about increasing contrast. That is of course why people use large telescopes but also seek out dark sky locations. A large telescope used in the city is only marginally effective without the contrast afforded by a dark sky.

 

With NV, you get BOTH increased light gathering AND increased contrast (with filters).

 

This powerful one-two combination allows one, for example, to see the Horsehead Nebula with a 4-inch refractor from a city location. Something that is impossible to do without NV no matter how large a telescope that is used because contrast is so poor.

 

What would you rather see in the eyepiece, a pristine view with nothing in it or a slightly noisy (noise which can usually be ignored) view but with objects like the Horsehead Nebula and MANY other normally unseen objects in it?

 

If you are a "visual astronomer", the tradeoffs (and like with most things there are some) when using NV are more than worth it. And, of course, you can always use regular eyepieces if the mood strikes. Although, since I started using NV for deep sky observing, my glass eyepieces have mostly remained in the case. 

 

Bob


Edited by bobhen, 15 December 2018 - 10:17 AM.

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#21 bikerdib

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Posted 15 December 2018 - 11:02 AM

Thanks for the detailed discussions.  The reason I asked the questions I did is because I considered getting into NV in the past but went with NRTV (also called EAA and yes it does stand for near real time viewing).  I'll stick with calling it EAA from now on.

 

Anyway, while EAA has the advantage of showing me color in lots of objects that through an eyepiece are greyscale, it requires extra time to gather the data, even though much shorter a time than "true" AP.

 

Due to it's sensitivity, I have what is arguably one of the better cameras for EAA but I'm still 90% to 95% visual.  That would be the appeal of NV to me.  There is just something special about stopping photons with my eye that have traveled millions of years and miles to reach me.  Seeing an image on a computer, even one that I captured myself, just doesn't have that same "magic".  And besides, there are TONS of images available in cyberspace that are MUCH better than any I'll ever capture.

 

I would like to try NV but even selling my ASI294 PRO would be only a part of the cost of getting into it.  And then if I don't like it...

 

Now if there is someone here on the forum that is in or near Houston that would be willing to let me try it...


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#22 Eddgie

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Posted 15 December 2018 - 12:16 PM

That is the appeal of most people using it.   It is just like using a conventional eyepiece.  You set up your scope, put it in, turn it on, and observe.

 

Now that is just one of many options.  One of the nice things about C mount devices is that they are very flexible. In addition to using it at prime focus (no objective on the device) you can also use it afocally (objective looking into regular eyepiece which allows you do cut the f/ratio of a scope by half (f/5 becomes f/2.5) or you can use lenses like SLR lenses or CCD finder scopes as mini telescopes.

 

Also, as I have said for years now, one of the most appealing things about NV is low power viewing (hand held at 1x to maybe 7x).  As it turns out, a lot of things are really huge, and using a small SLR lens, one can see a sky that is so full of stars and nebula that it boggles the imagination.  On an hourly basis, I probably do as much hand held observing as I do telescope observing.

 

Also, I use my Comet Catcher a lot because I can hand hold it or sit with it in my lap.  This means that in total, I do far more observing without a mount than I do with a mount.   I use the Comet Catcher and hand held to observe just about every night that there are open pieces of sky, even if it is just a 5 minute session before bed (I see shooting stars a lot!). 

 

This is a lot of the appeal.  It cannot show color and it can't match the resolution of a modern imaging camera with very long exposure time, but it is immediate and simple and lets you see a huge amount more than is possible with glass eyepieces and even from light polluted locations, you can see a lot of stuff that many struggle to see under dark skies. 

 

But the view can have noise, and the view is monochromatic.

 

Also, the apparent field is only 40 degrees and a lot of people think this will make for a horrible view, but generally, the small field is so packed with stuff that you simply are not aware of the apparent field.  Many people bought on my assurance that the 40 degree field would not bother them and while I am sure everyone would like a bigger field, the reality is that I don't hear anyone complaining about it.  Again, this is because ever field is a rich field when you are doing NV in the Milky Way.   I have seen thousands of stars in a single field of view.   Maybe 10s of thousands in 1x views under dark skies.   People often quote my "the sky is filthy with stars"  remark from the first time I used NV under really dark skies.   

 

I though would indeed say that it may not be for everyone. Image Intensifiers are starting to show up at star parties on a regular basis and it might be good to try to experience it first hand. 


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#23 Jeff Morgan

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Posted 15 December 2018 - 02:20 PM

While you can use NV to image, when used at the eyepiece, the view is not "Near Real Time." it is real time. (Though you can image with it if you like as well, and get very good results with very short exposures, but not in color).

 

Just to amplify the real-time point a bit ...

 

With my NV eyepiece in the hand-held configuration (meaning, 1x or small telephoto) I can be enjoying a bright and detailed view of the M8/M20/IC4685 complex.

 

Then as fast as I can whip my head around to the northeast enjoy an equally bright and detailed view of the Heart & Soul nebula complex. No integration, no trailing. It's just there,

 

Same with panning a star field. Absolutely zero trailing.

 

Betting against electronics over the last 100 or so years (and especially the last 50 years) has been a losing bet. NRTV will eventually drop the "N". Ideally a completely self-contained unit, something like an iPad with a 2" nosepiece on the back.

 

Then I will happily switch and enjoy the color views, retiring the NV eyepiece to one of my rifles (again illustrating the versatility of the device).

 

But is that summer 2019 or summer 2029?

 

One just never knows, eh?



#24 Eddgie

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Posted 15 December 2018 - 06:06 PM

Yeah, if someone came up with a real time CCD eyepiece that I could put in a telescope and use the same way as I do NV, an had the same sensitivity, same resolution, and could show color, I would grab it in a second.

 

 

I am not holding my breath though because I am not getting any younger. 



#25 Stargazer3236

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Posted 16 December 2018 - 02:47 AM

There once was an NV eyepiece by the name of 1RPD. Does anyone remember that?




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