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Ever wonder what the view is like with modern Image Intensifer?

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#1 Eddgie

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Posted 16 February 2017 - 05:15 PM

Same scene, both taken with the same cheap cell phone camera.

 

Power is 1x.

 

Now to the naked eye, I could make out shapes of things, so the camera isn't showing quite what I could see with a non-dark adapeted eye.

The reason I posted though is that people have seen blurry green pictures of the view though night vision gear, and I think that they believe that the resolution is low and that the contrast is poor. .

 

Modern NV has better resolution capability than most computer monitors and can have quite excellent contrast.

 

This is the view though an L3 filmless white phosphor tube.

 

NV  quality.jpg

 

And you have to remember, it is dark in the room.  Light is from a bit of spill from an under-counter night light in the kitchen though a door behind where I am standing and to the right, and a bit of light filtering in from outside.   Again, not pitch black in the room, but pretty dark.

 

I had to compress the picture to get it small enough to post so a bit of detail was lost.

 

The camera was just held up to the eyepiece, so you can see that I must have had the phone tilted because the left side of the field is a bit out of focus.   Camera's held to the eyepiece almost always struggle to show the scene with the same contrast that you see when you look though the device. 

 

These things are amazing for astronomy.  If your impression of night vision is formed from watching movies, you are not getting a really good representation of how sharp and and contrasty the view can be.

 

 I see things in my a 6" scope that I used to struggle to see in a 12" scope, and for brighter targets, the view quite spectacular.  For dim things, the scintillation in the tube does increase, but you can still see things with your existing small scope from the back yard of your close in suburban home that you used to have to go to dark skies with a big scope to see. 

 

In this picture, the device was focused on the coffee table, so that is where you would get to see the sharpest image it can produce, but again, I had to compress it to fit here and a camera used afocally rarely has the ability to reproduce the image with the fidelity that is visible in the eyepiece.

 

 

Sitting room.jpg

 

Also, does not look nearly this blue in the device.  A camera artifact I think.  Just not enough light to really tickle all of the sensors.  The view does though have a blueish cast but only a bit.  While the real time view is like a black and white picture in terms of quality, these particular tubes do show the bluish tint. 

I just wanted to share what the modern reality is.  



#2 Eddgie

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Posted 16 February 2017 - 05:17 PM

Uncompressed area of sharpest focus... And this is not a long exposure.  Just a point and shoot. 

 

I was standing abut 8-9 feet from the table.   On a laptop screen, this would be like being blown up a couple of times.

 

Note that you can see a reflection of the window blinds in the picture on the glass table top that does not show well in the compressed picture, and you can see the wood grain of the table. 

The above picture though is more representative of how the image looks to the eye in terms of sharpness.   Again, seeing this picture, the image in being virtually blown up.   Put the above picture far enough away from you that it occupies 40 degrees of apparent field and you get an excellent idea of how the image looks in person. 

 

sitting room uncompressed.jpg


Edited by Eddgie, 16 February 2017 - 05:25 PM.


#3 Joe1950

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Posted 16 February 2017 - 05:27 PM

So it works in light polluted skies? It doesn't just brighten the skyglow Eddgie?

 

That is amazing!



#4 Eddgie

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Posted 16 February 2017 - 05:37 PM

It does brighten the sky glow if you are using it without filters.  Gen 3 night vision though is far more sensitive in red than in the shorter wavelengths (and thousands of times more sensitive to red than the human eye).

 

Because of this, you can long pass Infra-red filters (610nm for typical suburban skies, and 685nm for very light polluted skies).  This means that almost all of the sky glow from artificial sources is greatly reduced, which darkens the background considerably.

 

Also, because the devices are super-sensitive to red, if you use a narrow band pass filter like a 6nm Hydrogen Alpha filter, you can see Nebula like the Horse Head Nebula even from light polluted skies.

 

They are very grab and go, and a lot nebula are best seen at very low powers.  I can see the California Nebula just holding the device right up to my eye with a 1.25" H-a filter mounted on the nose.    Or I can see the Horse Head Nebula by using it as an eyepiece (I can see it at 1x, but it is too small to show any detail).

 

Now this kind of tube is not cheap, but as compared to buying a 20 inch dob and taking it 50 miles to get to dark skies to be able to see things, in a way, it is cheap.  It turns a light polluted sky into a dark sky, or it turns a small telescope into a bigger telescope.    

 

A good used PVS-7 is half the price and will still show an amazing amount though. 

The purpose of the post though was to try to dis-spell the notion that these devices lack the ability to render fine detail with good contrast.   They can in fact show as much detail as the eye can see.  The resolution of the device presents image of detail down to one arc minute of apparent field, which is what the photopic eye can show.  

 

By comparison, the scotopic eye can only show resolution down to maybe 3 arc minutes of true field.   Since your eye is working closer to photopic vision when using the image intensifer, you can actually see finer detail than you could using your dark adapted eye (assuming the same magnfication, which is not always the case.). 


Edited by Eddgie, 16 February 2017 - 05:41 PM.


#5 Joe1950

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Posted 16 February 2017 - 05:47 PM

To be able to do where I live would be unbelievable!



#6 Eddgie

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Posted 16 February 2017 - 05:59 PM

This is one of the reasons I post on NV.   A lot of people today don't have easy access to dark skies, or they don't have the desire or ability to transport big telescopes.  And big telescopes can be even more expensive than NV!

 

NV Is amazing on nebula and even form the city, I can see things that would be almost impossible to see from my location almost any other way. 

 

NV Also excels at "Richest Field" viewing.  When I do get a chance to go to dark skies, the views are staggering. At Unity (which is what NV users call 1x) I can see thousands of stars in a 40 degree true field.  And I mean thousands upon thousands.

 

Under dark skies, you can seen nebula you probably have never heard of.  While you still have to drive, there is no big telescope to unpack, erect, and repack. 

So, things are always better under dark skies, but I can see things under my light polluted skies that I was never able to see before and I can see many of them using very small and very light telescopes! 



#7 photoracer18

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Posted 16 February 2017 - 06:32 PM

I used one of the early I-squared telescope intensifiers and I have to admit that being able to see things with a scope that was too small was pretty cool. Still it left a lot to be desired at that time. Biggest issue even now is no white light so color can't be imaged out of it very easily. Being more sensitive to red makes it just like a camera CMOS sensor which is good for Ha objects. Obviously you can use filters but the tube screens only have so much resolution.
You can get a cheaper setup using one of those DIY nightvision kits. One of my retired LEO friends built one to hunt varmints on the farm with an air rifle and I can say the image displayed on the smartphone screen are not bad. I do have a NV hunting scope for similar purposes but its only about Gen 1+ level not anything higher.

#8 Kent10

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Posted 16 February 2017 - 07:06 PM

Amazing stuff, Ed.  So this is the L3 filmless white phosphor tube.  Is it also the top of the line.  I have the NVD Micro that cost about $2000 used.  I have no specs on it so I doubt it is at the Ultimate level but I do believe it is one of the better ones and was hand picked.  I have been wondering how much better the newer image intensifiers would be over mine.  Is your L3 filmless white phosphor tube pretty much top of the line right now?

 

Thanks, Kent



#9 Eddgie

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Posted 16 February 2017 - 08:04 PM

Hard to know what the "top of the line" is but the L3 Filmless is probably near the top.

 

Now these pictures were taken in a room that was no where near completely dark.  I could see shapes even with unadatpted eye.   I just could not see much detail other than the major pieces of furniture.

 

I had an NVD Micro with a ULT tube and the performance for astronomy was not all that much different.  On more well lighted scenes, though, the contrast of the L3 tubes is pretty stunning. 

 

As the light gets ever dimmer, all of the tubes start to show scintillation, and the only difference is that when a standard filmed tube runs out of light, the L3 might still be producing an image that is only just possible to see.  Most of the difference is going to be seen at the threshold of performance.

When using in a telescope, the difference between what you have and the L3 is probably not all that great. 

 

Where the L3 tubes excel is that they have amazingly low EBI.  This is the background noise in the tube.   The filmed tubes can have EBI in the .8 to ,9 range, but the filmless tubes can be in the .1 or .2 range.   This translates into "Clarity."  When the gain is turned down a little, it is almost like looking though a regular eyepiece.  Sky gets almost  black.  In a filmed tube, sky can stay green even under very black conditions.   The EBI is like a faint background noise.   The L3 is better, but the difference would be maybe like the difference between an good ED and an Apo.  Small, but if you know where to look, not terribly difficult to see.

 

The Micro came in a bunch of different tube grades though, so hard to know where you are.

 

I had the Micro though and it worked great!


Edited by Eddgie, 16 February 2017 - 08:06 PM.


#10 Pierre Lemay

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Posted 16 February 2017 - 08:49 PM

Edgie, I have three questions:

  1. How much do brand new, top of the line, Gen 3 night vision devices cost?
  2. Where can they be purchased?
  3. Do you know if the Gen 3's are still ITAR (International Traffic and Arms Regulation) controlled (see here for detailed information)? If this is the case, they cannot be sold to non US Citizens, without US State Department permission (it would be a Federal offense to do so). Up until recently, here in Canada, only Canadiam Army personnel were allowed to use the Gen 3's. Maybe this restriction has evolved as they become more available? Or, perhaps, there are non-military versions available to the public?

Thanks. 



#11 Jeff Morgan

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Posted 16 February 2017 - 11:10 PM

The purpose of the post though was to try to dis-spell the notion that these devices lack the ability to render fine detail with good contrast.   They can in fact show as much detail as the eye can see.  The resolution of the device presents image of detail down to one arc minute of apparent field, which is what the photopic eye can show.  

 

Naturally people get excited about NV. And why not? Biggest relative leap in performance since Galileo in 1609.

 

But it does not photograph well from a cell phone. Neither do conventional eyepiece views, as your thread suggests.

 

With respect to resolution, that really is the secret. Many objects are bright enough to use the direct vision of the fovea. Color is beyond these devices, but the cone density in the fovea is very high, and has about 3x the average resolution of rod cells. The resolution gain comes from the eye, not the aperture.

 

The HorseHead is a popular winter target. With NV and a 12nm H-alpha filter from my suburban skies:

 

- At 1x I'm pretty sure it is there, but only as a dark notch that stretches my 20/15 acuity;

 

- At 5x it is definitely there, direct vision; and

 

- At 19x (5.5" aperture) it is definitely there and detailed, appears to be hanging in 3D space, and frames nicely with the Flame Nebula and Alnitak in the field. Easily tops the view from a 22" scope.

 

Of course with conventional eyepieces, having 2nd magnitude Alnitak in the field pretty much guarantees you will not see the HorseHead .... as does observing from suburban skies.



#12 Richard Whalen

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Posted 16 February 2017 - 11:13 PM

I believe certain government employees are now using gen 5.0, or so I've been told.



#13 Jeff Morgan

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Posted 16 February 2017 - 11:21 PM

Is your L3 filmless white phosphor tube pretty much top of the line right now?

 

At the risk of speaking for Ed ...

 

He and I have L3 tubes with very similar specs, purchased mid 2016.

 

Last week I was speaking with the vendor (Rich at Ultimate Night Vision) in regard to rifle thermal sights, and he touched on the new L3 tubes as well as the new Photonis tubes. Bottom line was my L3 was considered a "Super Tube" six months ago - but no longer. L3 is producing even higher specs now. Progress marches on.

 

According to Rich the Photonis tubes are also quite good. 10% more expensive. Better in the blue spectrum and "high light" situations (background light as one would expect near human habitation), although he says L3 is still better in the very dark environments. UNV has a youtube video that compares the two in high light conditions.



#14 mkothe

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Posted 16 February 2017 - 11:26 PM

Eddgie,

 

thanks for starting this thread. I have been intrigued by what you have reported at times, but have been hesitant to dive into the EEA forum and brave the learning curve, partly because I doubt that an investment is in the near future for me. Since this is focused on a specific subset of EEA, maybe this thread will answer some of my questions like:

  • Is this basically like using any other eyepiece in the focuser of my existing scope? 
  • How is this powered? internal battery, or from some external power supply?
  • How is magnification varied?
  • What is a good setup if I value a "natural" feel over maximum sensitivity?
  • How much tinkering is required to make this work well (hand-picked tube, filters, etc.)?
  • How fast will a given setup be outdated and superseded by significantly better equipment? 
  • Will I ever use a regular eyepiece once I get one of these?

No need to answer all of this specifically, but maybe the discussion will address most of this over time. If you aware of existing threads that cover much of this, I'd appreciate the pointer.

 

Michael



#15 buddy ny

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Posted 17 February 2017 - 02:22 AM

Thanks E

Ive been following closly the Threads new & old ,, here & elsware

about The NV capabilitys , Ive used NV once in a Boroscope that was slated for military use in the early 2000's

It blew me away then!! I can only imagine what 17 years of R&D have created

IM no longer on the fence about NV Tech ,,,decided to Save the Cash & take the leap

cant wait,,

kind of like being introduced to astronomy all over again

But thats a great thing



#16 bobhen

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Posted 17 February 2017 - 09:39 AM

Eddgie,

 

thanks for starting this thread. I have been intrigued by what you have reported at times, but have been hesitant to dive into the EEA forum and brave the learning curve, partly because I doubt that an investment is in the near future for me. Since this is focused on a specific subset of EEA, maybe this thread will answer some of my questions like:

  • Is this basically like using any other eyepiece in the focuser of my existing scope? 
  • How is this powered? internal battery, or from some external power supply?
  • How is magnification varied?
  • What is a good setup if I value a "natural" feel over maximum sensitivity?
  • How much tinkering is required to make this work well (hand-picked tube, filters, etc.)?
  • How fast will a given setup be outdated and superseded by significantly better equipment? 
  • Will I ever use a regular eyepiece once I get one of these?

No need to answer all of this specifically, but maybe the discussion will address most of this over time. If you aware of existing threads that cover much of this, I'd appreciate the pointer.

 

Michael

One year ago, after 40-years of observing and after some downsizing, I too was a Night Vision newbie. Although I had read about the Collins NV eyepiece in S&T years ago and had seen a NV device brought to our club’s public star party years ago, I had no real experience. I spent one month doing some research and then took the leap. I purchased a NVD Micro with a tube spec that was on the upper end but not at the very top because I read that that particular spec gave good results. I selected a monocular over a binocular because I have trouble with binos and the Micro was very compact. I bought a .7nm Ha filter and a deep red, 685 long pass filter and an inexpensive adapter that screws into the end of the Micro that would allow the Micro to be used in a telescope just like an eyepiece.

 

After one year I can say that I have seen more previously unseen nebula than in the last 40. The Horse Head is an “easy” target now. The Rosette is like a dim photograph. The California Nebula is bright and “huge”. Objects like the Monkey Head nebula are bright and easy, and objects like Sh 280 and Sh 282 near the Rosette that most have never seen or even heard of can be picked up visually with a small, inexpensive 4” F5 achromat. With a longer focal length telescope, the detail in the core of M42 is better than a photograph. AND all of this is from my location in the “very” heavily, light-polluted Philadelphia suburbs.

 

Is this like using an eyepiece? Yes. And my Micro is lighter than say a Delos. 

 

How is it powered? Small internal battery.

 

Magnification? Like using a camera, you need to add barlows or focal reducers to vary magnification. Or change telescopes. Good excuse to own a small fast telescope and a mid-size, longer FL telescope. Alt/az mounts are nice to use as well.

 

Sensitivity or Natural? You want sensitivity: My micro has a green tube. There is a monochromatic, slight gray/green tint to the object. Your brain will soon start to ignore that tint and mostly you just start seeing things in a monochromatic scale. I would take sensitivity over natural.

 

Tinkering? No tinkering with my Micro. Just remove the front lens that it comes with, screw on the adapter, screw on the 1.25" filter and place in a diagonal. I sometimes also use a 2” .7 reducer and I screw that into the bottom of the 2” to 1.25” adapter that came with my 2” diagonal.

 

How fast outdated? Probably quicker than you would like. Don’t worry about it. The views delivered by the device “you get” won’t ever change.

 

Eyepiece use? I have not used a regular eyepiece for deep sky viewing in a year. I’m sure I will, as Night Vision doesn’t do everything – what does? But I’m still pushing the limits of Night Vision. And besides, it’s really cool.

 

HERE is a website with more details.

 

Bob

 

Below are pictures of my Micro in a 2” diagonal and attached to a 50mm guide scope repurposed as a fast, 6x monocular.

Attached Thumbnails

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#17 Ed Wiley

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Posted 17 February 2017 - 11:08 AM

$3,920.00 — $4,597.00 when I looked it up on the Web. But perhaps that is not the same intensifier. Exciting, no doubt, but a budget buster for me.

Ed



#18 Eddgie

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Posted 17 February 2017 - 08:48 PM

Good used PVS-7s come up for well under $2K.   And with the PVS-7, you get to use both eyes!

 

Someone here or elsewhere on CN in the last couple of days said he found a used Micro monocular for $2K.

 

While not quite as good as newer monoculars, I stil use a PVS-7 for most of my telescope observing.    It is essentially like an image intensified binoviewer (though it will reach focus in almost all telescopes without the need for a GPC or barlow).  Not as sharp as monoculars, but still have great IR performance and will help a telescope perform like double the aperture. 

 

You can also buy a good tube for around $1K and put it in a body.  It is bascially "Drop in".  You can buy complete PVS-7 bodies for $700.

 

If you can live with blemishes, you can buy a tube for as little as $500.


Edited by Eddgie, 17 February 2017 - 08:55 PM.


#19 mkothe

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Posted 21 February 2017 - 07:49 AM

A couple more questions about the view:

 

Is the quality good enough to show quality differences between good and very good optics in the scope, or are such differences covered up by the resolution etc. of the tube?

 

What about the scintillation? The still images in the thread below that was included in a link above look great, but there are real-time videos (post 11) that have a lot of "noise". Is that seen with all NV tubes? It seems like this would distract from the "realness" of the view and along with the color remind one that one is looking through an electronic device. 

 

http://www.cloudynig...p-night-vision/

 

Thanks,

Michael



#20 Eddgie

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Posted 21 February 2017 - 08:24 AM

It is super-sensitive to some errors.   In particular, an achromat will not focus stars sharply unless you you a heavy IR Pass filter (Blocks light wavelengths shorter than 690nm).  This is because while the eye cannot see defocused red and blue, the image intensifier does.  Because the device is sensitive in red, you use the filter to block out the defocused yellow, green, and blue.   This could cost you on performance of extended targets (if you want the stars to be sharp in the background field of a galaxy for example) and some limiting magnitude on some fainter stars.

 

An Apo by comparison can be run un-filtered in darker locations. I have been using my 80mm Apo more and more un-filtered even in my light polluted location simply because I think the fainest stars are a bit easier to see even though the background is brighter.

 

So to me, that means that just like with an imaging camera, the difference in telescope design matters, but the difference in optical quality not as much because you are never viewing planets with NV. 

 

Frankly, I prefer reflectors for NV though others are big champions of big fast Achromats.  I personally think that reflectors are far superior for NV because they can be used unfiltered, and because they can be made to work far faster than refractors.  I have a 6" f/2.8 reflector on order and I can't wait to get it.

Reflectors though will show coma in a way that make the coma look like a spot diagram.  The faint comatic tail that goes unnoticed in a fast reflector will show more easily if you look at it with an image intensifier.   

 

Design wise then you can filter, but the more perfectly colors are focused the better, and a coma corrector becomes pretty important past about f/4.5.   The field of view is narrower than you will get with any eyepiece having a field stop of 18mm or larger, but the sensitivity of the intensifier will show you the real damage of the design (Chromatic Aberration or Coma). 

 

A high end tube can resolve detail down  to 1 arc minute of apparent field.  Now since this is about as high as the photopic eye can resolve (and 3 times better than your scotopic eye can resolve when fully dark adapted) is is possible to see more fine detail in Nebula with NV than you can with the naked eye (using the same scope of course).

 

The resolution is much better than an HDTV.

 

On very dim images there is noise, but you can see so much more than you rarely notice it.    On bright images like Orion, it is more like a black and white photo.  Camera's struggle to capture the fidelity of the view.   On very dim targets though there can be noise.

 

But I can see the Horse Head Nebula from my semi-urban front yard with a 5" telescope.   In the context of the new things I can see, the noise and scintillation seems to be pretty moot.   But that is me.  If the noise on dim objects and scitillation would bother you and you can't see some of the things we can see, you can get there with a much bigger and much faster scope, or by getting to the darkest skies you can find. 

 

I can actually see the Horse Head Nebula itself at 1x, hand holding the device. In the same field, I can see the Rosette, the Cone, the Flame, Orion, and several others all from my light polluted front yard.  At 1x though, I can't even see the notch of the head itself because of the low power.  At 3x I can see the notch.  At 18X, I can see the curve of the top of the head and back of the neck, but I can't resolve the nose of the horse.  At 55x in my 12" dob, I can fully resolve the horse head itself.   Under dark skies, I can see the entire arc of Barnard's Loop with the Angelfish Nebula along with all of these other things in the same 40 degree true field, all set in a field of thousands upon thousands of stars.     I see nebula that I did not know existed a year ago.   I resolve Globulars at 7x.   I can partially resolve Globulars that I could barely make out in the eyepiece two years ago.

 

Under dark skies using an 80mm Apo, I was able to see three or four galaxies in the same field of view and not just as faint unresloved smudges. I could see shape and detail.   And that was using just an 80mm f/6 Apo.

 

I can't wait to get my 6" f/2.8 reflector!!!!


Edited by Eddgie, 21 February 2017 - 08:32 AM.


#21 bobhen

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Posted 21 February 2017 - 10:42 AM

I’ll just add my thoughts to Edggie’s…

 

I just had one fantastic night last night using my NVD Micro and a Tak 120. 41 objects that ranged from a detailed Rosette Nebula to a 3-D, cloud-filled view of M42, to the Flame and Horsehead Nebula to the brighter sections of Barnard’s Loop to M35 and an easy and bright 2158 in the same view to the easy-to-see mottled, lumpy, clumps in M82 etc. and all from the light-polluted Philadelphia suburbs and with a “small” 120mm refractor.

 

The green tint in my Micro is really a non-issue, as your brain just starts seeing in mostly monochromatic gray scale on most objects.

 

Scintillation is there but the brain pushes this into the background, as you concentrate on the object of interest in the field. This is sort of like having a conversation in a crowded room. Yes there is background noise but you can tune that noise out and just concentrate on the person speaking in front of you.

 

At first you realize that you are looking through a “non regular” eyepiece but you soon just don’t care! The more you look through a NV device the more you forget what a regular eyepiece view looks like and the NV view becomes the “regular” view.

After a month of Night Vision viewing, I was shocked when I looked through a regular eyepiece – and not in a good way.

 

If you use filters (and all of my viewing is with filters) then an inexpensive fast achromat is just fine. I have a 102mm F5 refractor that works really well with filters.

 

If you want image scale (magnification) for small objects and you still want portability, you might want to consider a compact scope with a long focal length. I have a Mewlon 210 but an SCT will work just fine. They can be reduced with an inexpensive 2” .7 reducer, as well.

 

Bob



#22 mkothe

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Posted 21 February 2017 - 10:56 AM

Thanks for the detailed replies. I am really curious to see this for myself (though it will be a while before I can take the plunge on one of these). 

 

Are there any users in southern New England that would be willing to let me have a look? I'm about halfway between Boston and Providence.

 

Thanks,

Michael



#23 Eddgie

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Posted 21 February 2017 - 01:08 PM

Thanks for the detailed replies. I am really curious to see this for myself (though it will be a while before I can take the plunge on one of these). 

 

Are there any users in southern New England that would be willing to let me have a look? I'm about halfway between Boston and Providence.

 

Thanks,

Michael

This is really an excellent plan.   If you can see one at a star party it really gives you an immediate and free way to see if you would like it.

 

The purpose of my post was to dispel the notion that the view in NV is less than very sharp.  Modern intensifiers can provide much sharper views in the dark than the scotopic eye can.  For bight objects like Orion Nebula, it is almost photographic!

 

And while it may seem expensive, used PVS-7 coupled with a 10" dob will be like driving an hour out of the city, or will be like using a 20" dob in your back yard.    Drives to the country are both time consuming and expensive (if you do it a lot). 20" dobs are very expensive too!    

 

For someone that is considering upgrading to a much larger scope for home use, or for someone that is frustrated with the challange of seeing anything from their suburb or close in city location but can't drive to dark skies, this starts to become a more attractive propostion. 

There is also EAA using the new, inexpensive video chip based imagers.  These are not "Real time" like NV, but it is incredible what they can show in 30 seconds!

 

For those that want to be uncumbered by screens, cables, and cameras though, and want the option of doing Hyper-rich field low power observing, or boosting the aperture of a current scope, it starts to look appealing.

 

I observe pretty much every night I can see stars.  Most often, I take out an image intensified device and just do low power (1x and 3x) scanning.   If I use a scope, I can just use it in a small scope on an alt-az mount and turn it into a big scope I can carry around the yard to better viewing vantage points.   

 

Or I can plug it into my 12" dob and see things I have never seen before from my location, or struggled to see at my nearest "Dark Sky" site, which is not so dark these days.

 

I have so many "Firsts" with NV that it is hard to believe.  Things that I did not even know existed two year ago.



#24 Eddgie

Eddgie

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Posted 21 February 2017 - 01:15 PM

And this is really odd-funny.  I used to think of the Orion Nebula as a "Big" nebula.     These days, I think of it as kind of small.

 

I see nebula now that fill the eyepiece of my 80mm Apo.   I saw the Heart Nebula a month ago from south Texas under fairly dark skies, and if practically filled the 2 degree field of my eyepeice.   The detail was considerable and the only time I have seen more detail was when I saw images on the web.

 

Other big nebula that you can see are the Soul (next to the Heart), the Seagull (really huge and mostly unknown by amateurs) Barnard's Loop, California Nebula (extends outside of a 2 degree field and shows considerable structure), Veil, Gamma Gygni complex, North American and Pelican (takes about a 4 degree field to show them well),  big nebular clouds east and north of Rosette below Cone... And so many more.

While big scopes excel at showing very small things, NV is utterly fantastic at showing things that are simply to big to see any other way other than with the naked eye, but with much more authority and detail.

 

Again, really a post intended to show how sharp the image can be.   This is one of the main misconceptions I think about NV.  People think that the image is not all that sharp or well defined and in reality, it is about as sharp as the eye can see.



#25 caveman_astronomer

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Posted 21 February 2017 - 01:40 PM

Pics of some DSOs with these?

 

 




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