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Home > Reviews > Imagers > Other > Meade NightView CCD Night Viewing Device

Meade NightView CCD Night Viewing Device
By Ed Moreno - 2/8/2006

Review of the Meade NightView Low Light Viewing Device

I am such a freaking geek.

Had some coupons from Astromart for reviews I had written, didn’t know what to get. I mean I must already have owned almost every kind of telescope ever made… Well, maybe not…

I cast my geeky little eyes across the vast universe of other astronomical paraphernalia, but alas, no new eyepiece, mount, finder, book, shade, cover, case, are astro-gadget caught my attention.

In desperation, I spread my search across the Anacortes web site, and FINALLY, found something new to spend my money on: a night vision viewer.

Now I am getting to be an old geek. In fact, I remember seeing my first “Starlight” scope while serving as a young Marine near the close of the Vietnam war. These scopes were VERY rare, considered secret, and had only been used at that time by the most elite Fleet Marine Recon units (no one you would want to meet in a dark ally if you were feeling frisky, I promise). I was given one to use as part of some field experimenting that we were doing. This was a Gen 1 device, and frankly, I was not impressed. Oh, I could see well enough with it to shoot in the dark but only just (but luckily, with an M60 machine gun, well, you only have to aim "Approximatly"). The “Picture” was grainy, with very low contrast.

Here we are more than 35 years later, and you can order night vision devices on the internet. I had toyed with the thought of buying one for many years, but never got over my initial poor judgment of the technology, though I can’t imagine that even the cheapest night vision viewer would be superior to the vintage DOD “Starlight” scope of yesteryear.

Well, I didn’t NEED a night vision device. But being well enough off financially to be in the telescope buying hob…. Sorry, I mean being well enough off to be in the Amateur Astronomy hobby, I can sometimes also afford other gadgets as I please.

So, anyway, I decided to do a little research, before selecting a viewer, and went out into the boundless reaches of the worldwide web to see what I could find out.

It seems that the “Starlight” technology has indeed progressed. There are “Gen 1,” “Gen 2,” Gen 3” and even “Gen 4” devices, each offering progressive improvements in performance. There are also “Gen 1+” offerings!!! But my research quickly led me to believe that my budget was going to limit me to the Gen 1 category.

Now the basis for these devices is a light amplifying photomultiplier device. These collect the photons being reflected from the environment and basically supplement them (non-technical term) with other photons provided by the device, and smash them up against a phosphor screen next to your eyeball. This is actually simple technology, and the prices for Gen 1 devices reflect this. The Gen 1 devices though, have very low resolution and contrast as opposed to the Gen 2, 3 and 4 devices, and there is the rub. I was worried that in fact, the Starlight scope that I used in the Marine Corps so long ago probably WASN’T going to be greatly surpassed by an inexpensive Gen 1 device. The specs indicated a very low line count for the phosphor screen, and the underlying technology itself appeared to be the same.

I was almost ready to just pass and move on to spending my money on something else until I saw the Meade NightView.

The Meade NightView represents a different approach. Rather than using a photo-multiplier tube, the NightView “uses a Sony High-sensitivity CCD Image Sensor and Displays Through a Premium Ferroelectric Liquid Crystal Camera Ocular.” (Quoted from sales brochure.)

So basically, they have taken a VERY sensitive camera chip along with a standard video camera viewer (the kind with the tiny screen built INSIDE the camera case) and packaged it together without the recorder, but with an infra-red LED emitter array to provide light for zero light scene illumination. T

There is a 12mm Camera type lens at the front of the unit that needs to be focused, and there is also a focuser over the tiny internal view screen. To use the unit, you simply turn it on, focus the objective, focus the eyepiece, and view. The internal viewer is black-and-white, just like gen 1 video cameras, but that doesn’t matter much from a night vision standpoint. The NightView comes with 3 color filters that can be inserted into the viewscreen eyepiece. The first is a neutral density (maybe 70%), for just reducing the glare (that little screen is pretty bright at night, and it would light up your face if you were trying to stay concealed when used without the ND filter). The second is a GREEN filter, and as you and I know from our incredibly broad knowledge of the human eyeball, it is most sensitive to green light, so this filter is said to give the best CONTRAST performance (I think that this is true from using it and comparing it to other filters). The final filter is RED, and this is the one that you would probably use to best preserve night vision. It also seems to block the MOST light, meaning that if your desire is to stay concealed from your observing target, this might be the best choice, though if that target is smarter than a possum, I wouldn’t chase a cheating husband or girlfriend with this… More on that later.

The advantages of the NightView over the Gen 0 competitor are sharpness and resolution. This thing has far better resolution and contrast than the photomultiplier approach, however I don’t think that it has quite the same low light sensitivity. So that is the REAL tradeoff, but the question here is “Does the superior resolution and contrast make up for the inability to function in conditions below .03 lux, and does it all really matter anyway? Well lets take a closer look.

According to the tech spec, the camera CCD will work in light as low as .03 lux. Now a “Lux” is about the equivalent of .1 foot candle of light. Now you can look that up on the internet if you like, but take my word for it, 1 lux is not much light. But at the same time, to you and me (Astronomer geeks that we are), I will tell you that when your eyes are very well dark adjusted, 1 lux is like standing in bright moonlight! I mean if someone walked into a star party with a 1 lux light, why down here is Texas, I reckon we would want string that feller up…

How about .03 lux though? That must be pert near dark, yer might be thinking… So a device that can operate at .03 lux should just about let you see in the dark, yes? Well, in a word, no.
As it turns out, as pitifully dim as .03 lux is, in my carefully controlled and calibrated experiments, in my state of the art lab, I learned a lot about luxes and parts of them. And what I found out is that the human eye is surprisingly sensitive.

Here is what I did. I went into the closet. I know the trend today is to come OUT of the closet, but when you are pursuing great advances in the study of natural theology (any Baroque Cycle readers out there??) it is sometimes necessary to put oneself into such risky situations.

To see how sensitive the NightView was, I simply stepped into my walk-in closet and left the door VERY slightly ajar so some outside light could come into the space.

Now at first, of course I was totally blind. I couldn’t see a thing. Pressing the button on the NightView and bringing it to my eye with the red filter though, and suddenly, I could see EVERYTHING. I could easily see clothes hanging, Shoes in their rack, a C8 on the floor in the corner, old CG5 counterweight on the shelf… Yes, I could SEE in the DARK. But not all that well it turns out. The images seemed soft. The reflective spots on one of my cold weather boots was presenting a coma shaped flare. But more on that later. For now, back to the limiting magnitude testing... So, there I am, standing in the dark, wild lions growling in the distance… No, that is a different story. So there I am standing in the closet like a goofy geek, looking at my junk in the dark… But I could SEE my junk in the dark… Not sharply, but with enough contrast to clearly see that I was standing in a closet. Another great advance for science…

But being the astro-geek that I am, and being so freaking compulsive about comparing optics, I KNEW that this was not really a fair comparison YET. That I would have to let my eyes fully dark adapt to really see if the .03 lux contender could outshoot my oldest set of optics (my eyes) in this once in a lifetime contest of limiting magnitude. So I waited. And waited. And waited. And as I did, as you might expect, the visual purple started coursing through my veins. With every minute, detail began to emerge from the shadows. Cloths hanging on hangers emerged slowly from the depths of darkness. Shoes on racks began to push into view. The C8 struggled into existance from the shadows. As time went, on I could see an incredible amount of detail. In fact, everything seemed sharper and more detailed with my eyes working at f/1 than with the technology solution (I am in sales/marketing, can you tell). I was actually surprised really. I mean as much as I had seen in the viewfinder when I walked into the closet, I thought that the technology solution would be the hands-down winner her, but in the end, the old Gen 1 oculars seemed to be holding their own!

Repeated comparisons though, were hard. Even with the red filter on, when I would hold the NightView to my eye, I would loose some night vision in that eye, and the balance tipped to the NightView. A few minutes to adust, and the eyeballs were back in the game. So it seems that in fact, this was close.

Ok, fully dark adapted, it was actually too close to call, but I felt that I was indeed seeing a tiny more detail in the really dark spots with the NightView, but fidelity was without question better with the naked eyes. Everything that I COULD see was clearer and displayed more contrast range.

Next step… Close the door. That was the scary part, to be sure… Anyway, with the door closed, the only light getting in was from the small gap at the floor. It got really dark in the closet. I could see almost nothing, even though my eyes were fully dark adjusted. So now, I lifted the NightView to my eyes, and viola… Darkness. It was also not showing any detail…Yet… See, the NightView has a built-in LED Infra-red illuminator array. It has a variable step brightness control, and the moment I touched this control, detail immediately sprang into view. Even on the lowest setting, the illuminator easily provided enough light to trigger the CCD, and all my stuff became visible once again. So, while unaided I was blind and the CCD wasn’t sensitive enough to work with AVAILABLE light, the Illuminator washed the scene in light. EVERYTHING was EASILY visible. So, the trick is in the LED Illuminator. Using it, I now knew that the NightView works in a dark closet! There was however very uneven illumination of the field. Photographers would classify the pattern of the illuminator as “Center Weighted”, meaning that there is a hotspot at the center of the field that illuminates about 2/3s of the view, but then tapers dramatically towards the corners.

Next, outside… Yes, it works. With the ambient light coming from neighborhood porches and such (no streetlights on my street!), I can see detail maybe 100 yards down my street. I can see people walking (my neighborhood is chocked full of walkers and they are out at almost ALL hours of the day and evening!).

My back yardis not as bright. Oh, I can see plenty well enough to see my CGE1 1400 and avoid running into it, and the NightView without the Illuminator doesn’t do THAT much better. But once my nightly possum migration starts, the Illuminator easily shows them walking nonchalantly right by me. I see their shapes with the unaided eye, but using the viewer, I see lots of the detail. The range of the illuminator though is not all that great. I estimate that it is very effective out to maybe 20 meters, but past that, I don’t think it adds much. Here, however is probably the rational for the center weighted nature of the illuminator array. There is a built in digital zoom (3x), and when you use this, it can extend the range of the viewer, but at a rather serious reduction in sharpness. More on sharpness in a moment.

Anyway, the viewer offers the opportunity for plenty of wildlife observing, and since I have owned it, I have seen lots of wildlife that used to be responsible for raising the hair on my back by shuffling around in the yard.

Ok. Let’s talk about “Sharpness.” Remember that I said earlier that when I used the device in the closet, things didn’t look really sharp? Well, being the total star-testing freak that I am, of course to me, anything with a lens should be able to be evaluated using this method! So, like the geek that I am, naturally I took the NightView out and pointed at the sky that night to try to star test it... First, I will say that the NightView actually seemed to penetrate quite a bit deeper on the dark sky, showing quite a few stars that I couldn’t see visually. But they were totally in the “Blob-ola” category of the imaging world. Not only were they total blobs, but a twist of the focuser displayed distinct COMA!!! Not just a bit of coma… No, I am talking about a freaking Halley’s Comet worth of the bad stuff. The star would spray out like bird droppings on the hood of a Rolls Royce! UGLY coma. BAD, BAD coma.

Determined to get a better evaluation, the next day I set up a crude artificial star and tested the lens. The NightView has a very handy feature: You can hook it up to a TV. I did, and when I defocused, I could see what to me looked like SEVERE collimation error. My guess is that this is an internal lens problem, because the defect rotated with the lens when I tuned the focuser. If it had been a problem of the lens not being square to the CCD detector, I would have expected the pattern to remain in the same orientation. Twisting the lens to defocus caused the point source to flare badly, with the flare rotating around the point source, growing progressively more prominent as the amount of defocus increased.

This puppy was sick. Using several daytime targets, like the LED numbers in my cable box, and adjusting the CCD sensitivity for minimum, I found it impossible to get a sharp focus. Also, the direction of bleed seemed to move if I changed my distance and rotated the focuser.

I called Meade. The rep sounded clueless. I explained in painstaking detail about star testing, and he said, “Well, I have never heard of that (Star Testing) before.” But they did give me a return authorization.

Three weeks later, the replacement comes. It looks like a new unit, so I don’t know if they evaluated the original one and decided that it didn’t pass, or if this is just the way they chose to handle it (my suspicion is that Meade is not the actual manufacturer, because I have seen the same unit under a different brand since buying this one).

Within seconds, using a bright reflection, I was able to immediately determine that this unit also had the same kind of problem. It did not seem as bad as the first unit though. In fact, I would estimate the severity to be maybe half. While this resulted in a great improvement in sharpness over the original unit, it still displayed distinct como.

I feel that the NigthView may be falling short of what the design might be capable of. When used at zero power, I guess that it is well enough, but when you trigger the 3x digital zoom, this thing just doesn’t really have the image quality that I THINK it COULD have. Having used CCD cameras with digital zoom before, I think I have a good idea of how good this kind of compromise can actually be, and the NightView seemed poorer in sharpness using this mode than even cheap digital cameras that I have used with similar levels of digital zoom.

Regarding earlier remarks about using the viewer for covert observation… Well, I suppose that is possible if you have a side business as a private eye. In fact, the RCA jack would make it VERY easy to record your subject for later viewing entertainment. But the little LCD screen is VERY bright without a filter, and only the red filter seemed to reduce that light to the point where it might be difficult to see your face because of illumination from the eyepiece. The other problem is the IR Illuminator itself. This thing glows dimly at night when used full throttle. The way the LEDs are set, the glow is suppressed quite well but ON axis… You know the place where the subject that you don’t want to alert to your presence is… well, the glow not all that invisible if you know what I mean. But the chances that someone stepping out of a badly lighted cheap hotel room and seeing you are, ahem, slim.

So, here is my overall take. It works. It works well enough that I will probably just live with the optical defect in mine, because I lack confidence that the next one off the shelf will be that much better, and my hunch is that it COULD be WORSE… Maybe this is as good as they get!

Am I sold on the concept of using a CCD in place of a photo-multiplier? From the sample pictures I have seen, I think that the NightView might provide a better result on inexpensive Gen 1 photomultiplier devices, and the added benefits of being able to hook it to a TV, use different filters, and to have the optical zoom are all attractive.

Am I sold on the concept of “Night Vision” in general terms? Yes. Mostly. In retrospect, there are other things that I might have done with my money that I would have been more satisfied with. But the night vision DOES work.

Am I sold on the NightView itself? Harder to say… Being totally anal toward optical equipment, I am rather bothered by the optical defect in both of the units that came through my hands. It DOES work, but well, I get the feeling that it is not working quite as well as it could! The images just lack the kind of sharpness that I thought I was going to get based on the published design specs. But when you compress all of that data down to view on a teeny tiny ½ inch LCD screen, maybe the thing is working close enough to spec that this is as good as it gets. I don’t know. I ain’t no stinking rocket scientist.

For those of you that read my reviews, you will know that it is VERY uncommon for me to submit a negative review. It is my nature to prefer to write reviews about things that I like. With the NightView, I am decidedly on the fence.

Pros:
See better in the night
Filters for different needs
Optical Zoom
RCA Hookup to TV or recording device

Cons:
Optical alignment
Somewhat less than really crisp images
TOO tight of an illumination field causing severe hot-spot when used at short range



Update… I invited a friend of mine to bring his outstanding Meade 8” LX90 to a small star party that I conducted in my front yard for the neighbors. He has a Gen 1 night vision monocular with binocular style eyepieces, and I asked him to bring it so we could do a comparison. Well, he forgot it, but he did have a chance to try the NightView. He was complimentary, saying that everything seemed clearer in the NightView than with his Monocular/Bino Gen 1 viewer, and he felt that the range was better as well.

So… Maybe there IS something to this…


Attached you will find a picture of the defocused articical star, taken from a Television screen that was hooked to the NightView... This is not a great picture, to be sure, but if you look closely, you can EASILY see the gross coma present. And remember, this was the BETTER of the two units....

Can you say "Coma?"






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