Hvx200 Not Optically Centered

shiny4

shiny4

Well-known member
.one months ago i have wrote to barry green about a possible problem of the hvx optics,but his answer was...noo!!!! all hvxs are all rolling out the factory exactly the same.but on the redrock forum i have read this:


(...)So ultimately I figured out that the reason I had to move the hvx so far to one side in order to line it up optically with the adaptor was because the camera itself was not optically centered. What I mean by that is that the camera was not shooting straight out of its own lens. And I confirmed that by only mounting the achromat, just like Ryan, and I could see it was off-center. So I had a friend bring over his HVX200 and when we put the achromat on his camera the edges of the achromat were perfectly centered on the image. (His camera is much older than mine) On his camera you could see the achromat evenly in each corner whereas on mine I could see the achromat all down the left side of the image and hardly at all on the right. So obviously all HVX cameras are not made alike. Note: we were ONLY mounting the achromat in the step down ring and nothing else. Another indication that something was not aligned is that if you look at the image on the screen as you screw on the achromat the whole image shifted in a circular direction. So this also indicated that the lenses were not aligned optically even though they were aligned physically. So I called Panasonic technical support and ended up shipping the camera to Panasonic. I also shipped them two step-down rings (I wasn't comfortable shipping them my achromat) the 82-72mm ring for the achromat and the 72-55mm used for hard mounting. This was so they could mount the step down rings and see that the resulting circle was not centered in the image. They requested these after I sent the camera because, believe it or not, they told me they had no way other way of checking what I was talking about.

After a few day delay while the technician had to overcome internal hurdles to get permission to open a camera that appeared to be fine, the guy was able to fix it to an extent. He shipped it back to me saying he was able to improve it by 80% after spending 4 hours on it. I guess he reached his allotted time limit. Well 80% might have been an exaggeration, but it was better. (...)
http://www.redrockmicro.com/forum/viewtopic.php?t=3149&postdays=0&postorder=asc&start=30

I THINK THAT I HAVE THE SAME PROBLEM.:crybaby: :crybaby: :crybaby:
IT IS POSSIBLE TO RESOLVE THIS OFF -CENTER OPTICS PROBLEM AT 100%??
I WAIT MORE TECHNICAL COMMENTS.:dankk2:



 
At the end of the day it is a $5000 camera. It's not going th have the same accuracy built in as a $50,000 camera. Put up with it or buy a proper camera.
 
Still, for $5k, I expect the optics to be lined up! Saying a $5k camera is cheap is just absurd. I notice this, too, when using the Schnieder Optics 2.0x Teleconverter with my HVX. You'd think Panasonic would have given us $5k worth of quality. And don't get me started on the flimsy, easy to distroy 4-pin Firewire port on a TAPELESS camera...

But to dismiss this as just normal for a $5k camera? You have GOT to be kidding, right?
 
I'm with you BenB. If "TheEngineer" is actually an engineer, he's got to be kidding. No engineer would say put up with it seriously.
 
So is the $5000 camera supposed to be just as good as the $50,000 one then?? I'm with then engineer of you get what you pay for. And in the case of the HVX we are getting way more than what we paid for it... Its a very nice camera with some very nice features and a picture that rivals many cameras costing way more than 5000. But at the the end of the day the guy with the 50,000 camera has a 50,000 camera and the engineering that goes into one. We have the engineering that goes into a $5000 camera. Any actual engineer knows about tolerance levels and that higher tolerances cost more money. So i'm thinking "the engineer" is an engineer. Its like saying a chevy should have the fit and finish of a mercedes. Thats just crazy. I'm guessing that the Varicam probably IS optically aligned straight from the factory. Not trying to start anything and sorry if I hit any nerves, but theres no sense in pretending you are getting the best camera in the world for $5000, I'd be a little freaked out if it didnt have some flaws.
 
I've experienced the same thing with the insert on my Chrosziel mattebox. It only creeps into frame on the left side, worse in the top left corner. Wouldn't this have more to do with the lens assembly's position relative to the body though? Or maybe how the in camera electronics interpret the ccds? (reading about what was said in the hydra thread).

If the optics themselves were out of whack, it would be pretty impossible to acheive focus.
 
I'm not an engineer, but I've noticed that the focus on the HVX seems to "roll" unevenly across the focal plane in a diagonal lower left to upper right trajectory.

e
 
jdajda said:
So is the $5000 camera supposed to be just as good as the $50,000 one then?? ... But at the the end of the day the guy with the 50,000 camera has a 50,000 camera and the engineering that goes into one. We have the engineering that goes into a $5000 camera. Any actual engineer knows about tolerance levels and that higher tolerances cost more money. So i'm thinking "the engineer" is an engineer. Its like saying a chevy should have the fit and finish of a mercedes. Thats just crazy. I'm guessing that the Varicam probably IS optically aligned straight from the factory. Not trying to start anything and sorry if I hit any nerves, but theres no sense in pretending you are getting the best camera in the world for $5000, I'd be a little freaked out if it didnt have some flaws.
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actually the engineering that went into the HVX probably cost more than the engineering for a 50k camera, simply because they're making and selling way more of them...
If you drove the chevy off the showroom floor and it pulled to the left, would you then be saying , well it is a chevy so what the hell.....i doubt it.
For my 5k, the camera better be aligned. It doesn't sound like you or TheEngineer have the same notion of quality. I don't give a damn how cheap or expensive it is, it had better work properly.
Incidentally, why would you be "freaked out" if it didn't have flaws?
 
I'm dead serious. You get EXACTLY what you paid for. The camera performs perfectly as per specs - it was not designed and built to work with all sorts of bells, whistles and adapters you guys tend to put in front of it. It's like attaching a rocket engine to a VW beetle and complaining that the wheels are falling off after 300mph. HVX is designed and built to perform using its lens - is the picture right (color, geometry)? Do you see any problems on a test chart when you use ONLY the camera's lens? Panasonic (and I'm not standing up for them here) is not liable for how the camera performs or not beyond that. You obviously have no idea how much time goes into assembling the CCD block and how many fail, especially with a system that's using pixel shifting where you have less room to correct in electronics. It is not as much as how much went into designing this box, it's how much it actually cost to bring each one of them to specs reserved to the top of broadcast gear. Where do you think the difference is coming from? >-(
 
I think "The Engineer" is being strangely harsh and dismissive, regardless of whether or not he has a point.

The real question is whether this shift (which presumably is the lens/ccd block being fractionally mis-aligned, rather than a lens problem, as the effects would be far worse) affects image quality in normal-use operations .... Using a matte box is normal use, as is a wide-angle, etc .. is the effect of a wide-angle lens visually lop-sided? Do you have unreasonable vignetting on one side when using a matte box? (or matte box+wideangle) ..

While initial my feeling was that it was sloppy of panasonic, I can only presume that this camera was on the edge of their acceptable manufacturing tolerances. There has to be quantified tolerances in every manufacturing line- In a prosumer can like the HVX the tolerances will be lower than a consumer cam ... and indeed in a high-end cam tolerances will be tighter still.

As I said, the real question is whether you can demonstrate a negative impact on the image in anything like "normal use" ... bolting on an acromat and 35mm adapter is great, but if it relys on more manufacturing accuracy than "normal use", then it's not *really* Panasonic's fault, or problem.

To link this back to what someone said-- if your car banked slightly to the left then you'd complain and have it fixed or replaced, of course .. but this is normal stated use of a car.

But I might be wrong- you really need to investigate what effects this has on your footage, use of wide-angles, focusing, etc.

Regarding focus sweeping across the frame, this is entirely linked ... in that case, the ccd block (or lens mount) are presumably very slightly mis-aligned (relative to the focal-plane), like a very subtle tilt-shift.
 
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[deleted follow up post]

(just re-thought this, it's incorrect, as the optical image is wider than the chip, an unused area isn't relevant.)
 
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overlandfilms said:
I'm not an engineer, but I've noticed that the focus on the HVX seems to "roll" unevenly across the focal plane in a diagonal lower left to upper right trajectory.

e
Click to expand...

I've noticed that as well - glad to see someone else is seeing that too- so I'm not just seeing things .... :)
 
So, if I buy a brand spanking new VW, and the transmission doesn't work smoothly, jumps, shakes, grinds, I should just figure I bought a cheap car and shut up about it?

If Panasonic didn't intend for the camera to have stuff added to it, why did they equip it with the attachment surfaces to have stuff added to it?
 
As far as my reply, just re-read epicedium's post and thats exactly where I'm headed. The VW or the car that pulls to the left should work as intended. Just because theres a place to bolt on a supercharger doesnt mean the engine should be balanced and blue printed to do so. And look at the doors of a chevy and see how they line up with the rest of the body panels. Now go look at the mercedes and they'll line up better. The attachment surfaces are there to attach things to yes. If I build a rocket launcher with a 82mm filter ring on the back end are you going to be angry with panasonic when it doesnt work. Panasonic designs these to work for panasonic. be glad there are standard attachment surfaces at all. could be like sony's slightly smaller hotshoe. And why are we expecting to put large amounts of glass in front of other large amounts of glass to work really well. While I do like the look of 35mm adapters and think they have a definite place, they're kind of a giant optics no-no. they're a workaround for not having interchangeable lenses. So I say do your best to have the optics re-aligned and call it a day. I'm just glad panasonic is doing something buy bringing this much technology and engineering to this pricepoint at all. Older camera people are continually surpised my camera costs less than $10,000. My camera works fine with its mis-aligned optics :) Rant over.
 
I somehow skipped over reading the engineer's last quote. Yeah hes dead on base. And definitely an engineer... nothing wrong with that though :)
 
I imagine the next step is to investigate just how wide the variance is amongst different HVXs ... how many are "a little out", 1 in 10? 5 in 10? How many are "a lot out", 1 in 100, 1 in 10?

Also obviously poses the question whether we're hearing specifically about mis-aligned HVXs because they are the worst offenders, or whether it's just because people have only just started noticing and talking about it, and it being the HVX is just chance....
 
Yeah I'd be curious to see how easily this is fixed too. Whats it take in the HVX to become optically aligned. I know the original poster mentioned one that was only able to be 80% aligned - any other stories about people doing this?
 
BenB said:
So, if I buy a brand spanking new VW, and the transmission doesn't work smoothly, jumps, shakes, grinds, I should just figure I bought a cheap car and shut up about it?

If Panasonic didn't intend for the camera to have stuff added to it, why did they equip it with the attachment surfaces to have stuff added to it?
Click to expand...


WEll i kinda agree with Engineer. The HVX200 was not designed to be used with a Mini35/SGpro/M2 etc. If he didint put the achromat on, he would never have known there was a problem, and he would have used the camera for years. because despite a slight misalignment (which wasnt noticable until he put an achromat on), the camera was perfectly functional. The filter threads are designed ot hold a wide angle lens at most. Maybe a UV filter. There is a reason thewhole front asseembly is held on with 4 tiny screws. its not really mento be bearing any weight. We push our cameras Very far. That great ingenuity, and we are all very clever with our tricks, but please, be realistic.
 
He said the engineer claimed an 80% 'improvement' (over it's initial state), which he felt was an exaggerated claim, but better than it was.

A slight mis-alignment wouldn't necessarily be a big deal ... It is presumably the prism and CCDs positioning within their block, relative to the lens mount. Nothing is perfect, it's all about tolerances- drawing a line and saying "anything below this is acceptable". (It's possible that different manufacturers draw their 'lines' at different levels.) A tangible mis-alignment would give you slightly lopsided lens distortions, such as barrel distortion, chromatic aberration, edge softness and vignetting, but in normal use these should all be *so* minimal that their being minutely lop-sided really isn't such a big factor. I suppose it would also mean that a wide view would be very slightly 'wider' to one side- the expansion of this area caused by the perspective of a wide-angle lens would probably bring this into the realms of being tangible, if the mis-alignment was great enough. The flattened perspective of a longer focal length would make it harder to see, I think. It really is possible that it's nearly impossible to show a visible difference in normal conditions, but I'm sure people will put this to the test.
 
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