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Can someone tell me how the once favored CX-161 compares to the new darling, the KX 131 in actual FPV use?

I bought a few CX-161 cameras before they went bye bye. Was this a bad move?

Edited by wmacky1

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Personally, I think the CX-161 performs a little better for me. But, the two cameras are very similar.

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I've flown a CX-161 for three years on various mounts, and it always seems a bit 'soft'/'grey'; my impression is that this effect is something to do with the terribly high contrast conditions these cams have to work under up there in the blue! So I too have been wondering about how it compares to the 131.

However... last year I was flying a camcorder (the diddy Xacti VPC5), to get 5 MPixel stills as well as dropout-free movies. Oddly enough, although we 'know' that camcorders produce more vibrant pictures than these board cameras, the footage it produced in the air had a very similar sort of 'washing out' of the images - I concluded that it's therefore a contrast problem. Comments, professional cameramen?

(The VPC5, although a small (120g) camcorder, needed a relatively big mount which wobbled, which made the 5MPixel stills disappointing. And stiffer = heavier, and since the original needed a 3m electric soarer to stay up, I've moved away from this. Zooming in VR is quite fun, mind!)

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What are you using to record?

The Xacti records in MPEG-4, like quite a few usual recorders, which means compression. That has a big role to play.

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I'm recording to Mini DV -25Mbps - (rather than MPEG2 (6-8Mbps) or MP4 (2-4MBps). I'd have thought MPEG compression should maximise contrast/chrominance, rather than minimise it.

Perhaps the question of what compression is used is an important one. Kilrah, have you examples of different compression formats making these hi-contrast videos look worse? Why does an airbourne CCD image from 500ft look more washed-out than a digicam image from a hill?

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DV is perfect. No, I don't really have good comparisons.

But there's a thing that cam fool people too. Don't know if you've noticed that, but when you shoot video with your camcorder while framing on its LCD, the image always is more vivid than once you transfer it to the PC and watch it there. Camcorders' screens usually aren't neutral.

Talking of the KX131, it's the one I know of that will be as close to a camcorder (apart from the definition). I have a good 3CCD one with analog input, if I switch from the input to the internal camera I can barely see a difference on the LCD.

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If it is recorded in DV format, once transferred over to the computer in let's say Adobe Premiere or for the MAC Final Cut Pro, there is a filter on each where you can adjust the "levels", to bring it to more visually pleasing combination. Usually this filter will add to the rendering time, but I found this filter very useful in order to properly saturate the image - and bring out the details better.

Of course non of mine were aerial videos - I am just in the process of building my first vr plane:

Northstar Construction Page

A Northstar - can land and take off from water, has wheels for land, and as they say it is fast... The interesting thing about it, that usually this plane needs weight in the front to be properly balanced, in my case with all the video equipment it most likely will be properly balanced.

Thanks, Ox.

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Are you going to put a pan tilt in your Northstar? I have seen these fly, and they seem to fly slow with a lot of pitch up, which will really change where your camera is pointed as you change speed. They do look Like a cool design though, I have thought about one for AP too.

Ken

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Yes I am. The body is covered, and I am still thinking on what kind of material to do the top closure from so I can protect the camera from the possible water and wind. I need something see-through. Because of the camera the cockpit will be a little higher than usual, so I have to make a custom design there too. Also I want to make the pan and tilt such that I can look down over the side of the plane - a minimum of 45 degrees. I think this calls for a new design of pan and tilt where the camera is displaced 1"-2" i front of the servo and when it pans, ir moves ina semi circle.

From all I read about the Northstar is that they tend to be quite fast planes. You can fly slow as well, you can land it like a Condord with nose up and barely any forward speed, just by touching the water with the back of the plane.

If you get a grip on, and slow it down enough, it will float down vertically just like a leaf - assuming it is properly balanced.

I am also putting a Black box on it, so I will report back on the speed - possibly summer time...

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From all I read about the Northstar is that they tend to be quite fast planes. You can fly slow as well, you can land it like a Condord with nose up and barely any forward speed, just by touching the water with the back of the plane.

If you get a grip on, and slow it down enough, it will float down vertically just like a leaf - assuming it is properly balanced.

That is normal behaviour for a delta, they have a fantastic speed range. The down side is they are not very efficient but if endurance is not you number one goal then I think its a great idea. I'm surprised we don't see more of them as camera planes !

Terry

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you might look at this one:

http://digitalsurveillancesolutions.com/se...KPCHD230CWX.htm

I got it because its already in a tube, and making it water proof is easy. Mine is on a pan servo right now. Thinking about a tilt mount, but haven't built one yet. As far as wind, esp with a pan tilt head, I wouldn't try putting it inside the cockpit, you will never get it clear enough. Even with a clear dome, the sun will put glare on it. Just run it out in the air, everyone seems to do it that way, even the jet videos I have seen.

spec page:

http://www.ktnc.co.kr/product_04.asp

Here is some highly conpressed video:

http://video.google.com/videoplay?docid=60...3&q=rc+seaplane

In person it looks very nice. Not sure how it compares to others as far as back light comp, but at least as far as the other video I have seen, it's pretty good.

Inside, if I point it directly at a florescent light, the white celling in shadow is still visible off to one side.

Ken

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Has anyoned experienced Hi_Cam's EO5-380 CCD cam? (http://www.hicam.com.au/pro_x2.htm)

I am looking at purchasing one of their systems and was wondering how their EO5-380 compares to the KX-131. Both have CCD Resolution of 380 lines, but the Hi-cam cost $180 compared to lets say RangeVideo's KX131 at $85.

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~$400 and no camera? That seems a bit much considering it is only 200mw, a std rx, no diversity, std 8db patch, cheapo tripod. A 200mw tx rx is $115 from Future Hobbies, their 12db patch is ~60, or the 8db patch is ~$50 from lots of places. $180 for a 380 line camera is way too much. There are way too many cameras out there to pick just one, but I wouldn't pay over $80 for 380 lines, 480 line cameras can be had for a little over a hundred. Future has a good mic. pre wired for around $30.

If you need everything pre wired, then $275 gets you a 200mw system, with everything except the antenna. Incl a 480 line camera and battery.

Range, BW and others sell similar systems at varying prices. Unless you really want to buy from a company in Austrailia, I don't see the attraction.

Ken

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I was a just a little "off my rocker" when thinking about ordering from Australia at those prices. Local responses where not great then, but now ordered what I need. Thanks for your input!

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Has anyoned experienced Hi_Cam's EO5-380 CCD cam? (http://www.hicam.com.au/pro_x2.htm)

That's the Lawmate 200mW TX that can be found at BWAV or others, the camera is the cased KX131 and the antenna is the usual too. Good for one who doesn't want to bother with the wiring.

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my comments:

I use KX 131 see the videos if you like at the bottom of this page:

http://www.webx.dk/rc/video-wireless/video-osd.htm

The KX131 is a super low lux cam, so it is special good for indoor surveiliance projects, but for outdoor rc planes it perform bad !

due to too much light, just bad weater in the winter time is too much light over its regulation range, so the picture will change in color balance,

and add black edges before and after white stribes on darker backgrounds, reveling overdriven too sensitive CCD elements.

Adding sunglasses might help :-)

Now I am on the looks for a better cam, I dont care that much about the price !

any suggestions ? it is also ok if it is bigger and more heawy, but under 50gr is a must, and PAL mode !

Edited by ThomasScherrer

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Pretty strange, I've never seen that with mine. It has operated in all possible conditions, even in snow-covered places with bright sun, always perfect.

Video

Edited by Kilrah

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Kilrah, are you using the PAL or NTSC version ?

WOW nice video, nice senery !

How do you record in hi-res without the interlace blur problems ?

I just record in Quarter resolutions to avoid it, and get the files much smaller.

Your cam does exactly the same as I mention,

but since your background is so light, the problem is much less visible.

I could easyly find many examples in your video showing the problem:

http://www.webx.dk/rc/video-wireless/kx141...ght-problem.jpg

and here:

http://www.webx.dk/rc/video-wireless/kx141...ht-problem2.jpg

Any others with KX131 experiances ? and videos we can look at ?

Terry, nope, same Sxxx without OSD, that is checked :-)

PS: yes I am in the hunt for a new cam ? anyone with suggestions ?

Edited by ThomasScherrer

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PAL version.

Oh, the smear. Well, you'll get that with any CCD camera out there.

It's not due to image brightness itself, but rather to brightness differences between the different parts of the image. I.e that can happen indoors with a small light source that is bright in relation to the surroundings even if it's obviously a lot less bright than the sun.

Technically, it's an overload of the CCD transfer elements during sensor readout. The way elements are wired to each other in columns has the consequences of charges overflowing to the next elements of the same column when one is saturated. As the overall integration time is adapted to have a good exposure of the whole image, there's nothing it can do for a zone that is that much overloaded, and sunglasses wouldn't help as that would simply increase integration time.

You'll see that with camcorders too, and I even have a commercial DVD made with broadcast cameras where that can be seen. CCD digital still cameras will do the same in preview mode. When taking the shot it doesn't appear, as a mechanical shutter will block all incoming light while the sensor is read :)

The KX131 actually already performs well, I've had several other cams that would give a competely white screen in similar conditions. Here, at least you won't get lost :)

For other vids look at the website, there are loads of them.

I'm on the KPC-S700CH at the moment. Looks good, but I still miss testing it in real conditions to give my final word. And this week's schedule doesn't help :(

Edited by Kilrah

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Oops, forgot the bit about recording:

On these I used a PCMCIA video capture card, the supplied software was doing the deinterlacing automatically before encoding to MPEG-2.

Now I mainly record either with a DV camcorder, or with my USB capture card (new PC has no PCMCIA <_< ) using the DV codec. Both are then recorded keeping interlacing, and I prefer it that way as it will look much smoother on video equipment (when I make DVDs). That means I edit and export keeping the interlacing. But then, when encoding the web and other versions intended to be played on a PC I simply apply the softrare's deinterlacing filter (in Windows Media Encoder for WMV, VirtualDub for DivX or directly in Adobe Premiere).

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Thanks Kilrah, well I just got finish modifing another cam to have the same connector and pin out as the KX131, so I have two cams to test with at the field next time, I know from indoor tests the new one has much better picture and much less smear. but its case was almost 50 grams I had to remove, and construct a new case and support for the two boards using balsa and cyano, only 2gram for the balsa casing. so my new cam ended up only 2gr over the KX131. but ok it is 4 times as big :-)

it is actually a web cam called type XC77D/761 with PAL video out and 5V 350mA supply.

When I record using my USB2 grabber thing, a 7 minute film i 320x240 is 2GB !

so imagine a full resolution hehe..

but the cam does not have full resolution right ? why bother then ?

Edited by ThomasScherrer

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You might be recording with no compression at all. Use a DV codec, it has very low loss and already gives a 5:1 compression ratio. It will output about the same file size as you have now.

Here's a free one attached. I personally use Mainconcept DV codec, it's especially good and much faster at the same time.

Maybe the camera doesn't have a full resolution, but it definitely has more than 320x240. The one I'm testing is supposed to be a 480 line one and seems to actually have them. In all cases, it's always better to eliminate one quality reduction from the already long chain ;)

cedocida017_DVcodec.zip

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