Canon lens problem?

M

morgster

Active member
I have posted a still for you guys to look at. Any ideas what is happening here. It is a Canon HJ17x7.6 lens on an HPX3000... basically it is way more obvious that this is happening when the 2x is on.

As you can see the image in the centre of the screen is in sharp focus... the edges are way off. Thinking of sending the lens into canon to take a look.

Anyone know what this is? Any suggestions where to send my lens to have it looked at?
 
Wow, that looks just like the other Canon 17x7.6 issue from a few days ago. I wonder how close the serial numbers are on the two lenses?
 
Holy crap. I have that exact same issue with the exact same lens.

Panasonic and Canon were awesome about it at first (We'll send you a lens out in 24 hours) then they disappeared and we're still trying to troubleshoot it with our somewhat time challenged place we bought our camera from.

We have exactly that problem, exactly that bad, in that exact kind of shot, on our 500.
 
Really... the same lens? I have a fujinon CAC lens that came with the 500 which runs around $8000... but this one I bought for around $18,000 for my 3000 and is supposed to be the higher end lens that canon offers for HD cameras... the HJ series. First I thought it was my mattebox filters... so I changed them out... but then I noticed it without them. I guess I should send it to canon for them to look at it. Very perplexing.
 
Whoops. I have the 17-7.6 CAC from Canon that is displaying that exact same issue.

Here's the scary part, it was still there, to maybe a lesser degree, when we popped on one of those higher end Canon HD lenses.

Like I said though, the service guy from our reseller was in a hurry so we didn't get to do the type of testing we wanted. We're going to get the lenses back again, and try again.

We weren't able to do enough tests to conclusively rule out the lens or the camera.

The engineer did say our backfocus was a little off, but even after he corrected it, the problem still was there.

It's strange though, no one at dvxuser had seen that kind of effect before when I put up our still, which would suggest it isn't backfocus, because I'd assume the old hands would ID that at 100 yards.

But now, you have the exact same looking still on a 3000 and a higher end 17-7.6 as we do on our lower end canon cac lens and a 500.
 
I guess one test I should do is pull the lens off my 3000 and place it on my 500 to see if it's the lens or the camera... Then I should grab my Fujinon 17x7.6 lens that I got with my 500 and put that one on my 3000 to see what I get.

The funny thing about the whole thing is it's not really noticeable without the 2x on... and even then it's only really noticeable on shots with lots happening in them. I will be going back though my footage shot over the last few months to see if I can spot if it just started to happen, if it was always there, or if it is getting worse.

It is definitely not a back focus issue though... I've had them go out before and it doesn't look like that.
 
Latest news is that is a camera setting. It doesn't look like that on default settings but on the custom user settings it looks like that.
Will update when we find out more.
 
I pulled my lens off my HPX500 and was getting the same effect on that lens. I'm guessing there is something in the HPX3000 that needs to be set... Have let my Panasonic dealer know and he is contacting Panasonic. I will let you know what I find out.

What kind of camera setting are we talking about?
 
Apparently it is in our user settings. They downloaded our settings, applied them to their camera and were able to replicate the problem. Resetting everything on the camera back to default apparently removes the problem. I'm still waiting on more info from them. I'm hoping they've narrowed it down to a specific setting, and not a generic "you did something".
 
Welp, it's not a settings issue. We tested again today completely changing things around.

It turns out there looks to be a problem with the 17x7.7CAC we have. We can get a nice clean sharp focus on the test card, and it looks reasonably consistent edge to edge, however if we rack the focus just a bit instead of the whole frame going out of focus the edges of the frame go out of focus first, and then then center.

Very very strange.

We're still looking to canon to get us a replacement lens the same as ours.
 
Any news on this? Panasonic engineers now have our camera after the local engineers had a go at it. Did you get any resolution to the problem?
 
Welp, we've had panasonic look at the camera and canon look at our lens and it turns out, that's what the lens does.

The low end Canon CAC lens will just give you that result and that's it. The only solution is to go up to a higher end lens. Canon has been very accommodating, but unfortunately the cost is too great and we'll just have to live with the limitations of the lens.

We tried a higher end lens and did get better results. The interesting side effect seemed to be that the in camera focus assist and the focus in red on our monitor both became much more accurate.
 
I use a Canon SD lens on my 500, and I get a similar look when using the extender. I just have to make sure I don't get myself into situations where I'll need an extender.
 
I've owned a lot of lenses and I've never seen anything like that before. It's kind of an interesting effect, but completely unacceptable.

Zoom lenses for film cameras seldom exceed 10x1 (like the old Angenieux 12x120, or 25x250) and the good ones are usually 4x1 or 5x1 (I have a 30 year old Cooke 10.4x52mm super16 lens that compares with primes).

I've always felt that one of the weaknesses of the video marketplace is the lack of short range zooms. They try to make them all-in-one lenses - which made sense in the days of tube cameras when it was difficult to change lenses - but now it would be nice to have the option of smaller, lighter lenses for handholding and bigger, longer lenses for tripod work.

This all-in-one philosophy seems to be at the root of the problem here - asking too much from one lens.
 
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