From what I understand, this is an internal lens adjustment similar to an extender that switches the field of view. In 4:3 mode, the field of view over the entire CCD is wider than when it's in 16:9, albeit with the chance of some vignetting and/or poorer quality in the corners. When that 16:9 area of the CCD is cropped to 4:3, it matches horizontally what would've been covered with both the lens and camera in 16:9 mode.

The way I look at it, the expectations for the lens and camera are quite different.

Aside from the electronics/tape mechanism etc, the camera needs to maintain (logical) paralellism between the sensor and the lens mount, perform its beam splitting magic precisely, etc.

Given good manufacturing practices this is quite expensive, but not ridiculously so.

Compared to what is expected of the lens, the camera has the optically easy part of the job. Paying as much or more or a lot more for the glass makes excellent sense UNTIL you reach a point where the optical performance of the lens exceeds the ability of the camera to capture the improvement, at which point additional investment in the lens has zero payback.

It's like having a built in ratio converter, instead of having to place one on the front of the lens. The first sentence in that quote applies perfectly to the XL2 since it has native 16:9 chips. In 4:3 mode, the lens becomes 1.4X more telephoto.

-gb-

This is the point I was circling. What is the critical mass of these cameras in terms of lens cost versus camera cost?

thanks Earl and Greg
 

for the clarification.

Hey Eric, if we want to really hilight and compare the CA between the lenses, have them both shoot at close to full telephoto from beneath a tree which is sparse of leaves(as in lots of twigs etc), against a bright sky, and we'll soon see the comparison.

cheers

Adam

Adam, I wish my heart was protected with as much bubble wrap as that 18x was when the UPS man drove it back to our friends at TapeworksTexas this afternoon.

Although I did not shoot the scene you suggest here, trust me, I shot plenty of other troublesome conditions.

Same subject, conditions, and settings - Full zoom, 5.6, 1nd, 1/250 shtr, whites blowing out against a dark background.

Fujinon Th16x5.5BRMU @88mm bright whites/contrast

Fujinon HTs18x4.2BRM @76mm bright whites/contrast

Another difference between the 16x and the 18x is the servo zoom control speeds. While the 16x has only one speed, the 18x has seven - 1 (marked "S") through 6 (marked "F"), and then there was one more notch past "F" which wasn't marked. I assume that's "Superfast?"

Here's a video example of all the speeds of the 18x VS the one speed of the 16x

Fujinon 18x VS 16x servo zoom speed(s) comparison video

FYI, the last two settings on the 18x ("F" and the one after) put out a pretty aggressive gear driven growl when they drive the zoom so quick. I had the stock mic mounted just to take notes and it did not pick up the sound - but I still had the audio set on auto from my last project. I bet under some circumstances the mic (if it were mounted on the camera) could pick the noise up.

Brian, is this what you mean by "distortion?"


Fujinon Th16x5.5BRMU image distortion at full wide

Fujinon HTs18x4.2BRM image distortion at full wide

I'd also put in some verticals, but that would be part of comparing lenses.

I have the 18x4.2 lens on an HD250. Actually, I have a brand new one that also has the 2x extender. Anyway, I've noticed that at any aperture wider than f4, it exhibits a lot of longitudinal CA, meaning that as I rack focus, out-of-focus objects shift very blue-green or very magenta. However, as long as I'm stopped down to at least f4, it is not a problem and the lens is fantastic.

I can see this being a problem for filmmakers who want shallow depth-of-field to replicate the look of 35mm because they'll need to open to at least f2.8 to get that look on zoomed-in close-ups. It's a trade-off because as soon as you open up the iris, you begin to see the fringing around bright objects and areas of high contrast.

I would say this is not a failure of the lens but an inherent drawback of shooting with 1/3-inch chip cameras.

No doubt true
 

that it's a inherant drawback of 1/3 chips, and also HD lenses, but Eric I feel your pain after such a large investment.

There was at one stage a CA filter on DVinfo, I think it's fallen off, but you could filter out the purple and green in post, of course this is not ideal, but it's better than loosing a otherwise great shot because of the CA.
Are there any plugins out there guys to reduce this, I used a free six colour correction plug-in for Vegas, to reduce the amount of CA colour shown to get rid of it, of course it then saps that out of the whole frame not just that small intended target of that colour.

Are there any good plugins out there which guys that handle this problem better??

I think was you Tim Dashwood that had the 13x lens a while back? If by chance you've read this thread can you or any other players out there give us a example of the a worst case scenario with CA as a comparison with the 18x?

Regards

Adam

I think you'll find your lens is sharp throughout it's range whereas the 16x is very limited compared to it's zoom. The versatility is the value.

I suppose the other issue about making such a large investment on purchasing the higher end lenses is how long the JVC/HDV will be around before it is superseded by a higher form of HD. It makes commercial sense buying the stock camera even if HDV will be around for a few years but loading it up with all nice add ons might not except for people who can make their money back on enough commercial shoots. At the moment it appears that the entire technology is moving forward so rapidly that in three years time the camera might start to look like my old Canon XL1.

Having said that, even the most expensive lens available for the JVC is not particularly expensive given the cost of other HD lenses.

Rob

Magnified view of the differences in the dock footage -

Clearly blurry and loads more CA


Both lenses in macro, on the same flower -

Macro focus

well thats chalk and cheese there Eric
 

thats a vast improvement over stock lens, even though you had to close the lens down to get it, I suppose also over F4 you'll start loosing resolution as well?