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-   Sony NEX-EA50 (all variants) (https://www.dvinfo.net/forum/sony-nex-ea50-all-variants/)
-   -   Zoom problem (https://www.dvinfo.net/forum/sony-nex-ea50-all-variants/514236-zoom-problem.html)

Noa Put February 11th, 2013 02:07 AM

Zoom problem
 
I have reported this problem when I just got the camera (when I was filming at that casino) and I just saw another user complaining about it on Vimeo, has anyone else noticed this problem on their camera s well?

This is the video showing the problem:

Chris Harding February 11th, 2013 03:31 AM

Re: Zoom problem
 
Hi Noa

Would anyone actually zoom in and then immediately zoom out...I must admit I have noticed nothing but I will actually check my register signing shoots and cake cut shots which are the only time I will do a motion zoom combined with a tilt ..it's just to lead the viewer to a closeup of the marriage certificate and the knife slicing thru the cake.

It really isn't that bad and even noticeable at all..if it was then angry owners would have posted something by now. I'm sure if you look really hard you could find a few other issues too BUT would the viewer ever see it??

Saying it's a horrible lens problem is somewhat over the top I would say!!

EDIT: Just tested my camera and it doesn't do that jump or focus shift at all..both on the lens zoom lever or the power zoom rocker is silky smooth and reversing the zoom also is silky smooth. Maybe others need to test it?? To me my lens is 100% correct with no issues!!!

Chris

Noa Put February 11th, 2013 03:44 AM

Re: Zoom problem
 
Thx Chris for the test, that's what I wanted to know so it might be that there are some "faulty" lenses? In my case I see exactly the same issue as that other user, there is some kind of play that gives this jerky motion and a very short defocus at the start of every zoom I do and that for zooming in and out.

Also, do you have the zoom set to variable or fixed speed?

James Manford February 11th, 2013 04:33 AM

Re: Zoom problem
 
I've sold my E PZ Zoom lens ... I never liked motion zoom in the first place. This may apply to ALL the EA50's but as stated, would you ever zoom in and out so quickly?

I think we are expecting TOOOOOO much from this camera. On some websites, it is stated the EA50 is a 'entry level' professional APS-C shoulder mount camera, which automatically tells me Sony are coming out with a more refined model by the end of the year which may eliminate aliasing, moire, and this problem you have shown.

Chris Harding February 11th, 2013 05:20 AM

Re: Zoom problem
 
Hi Noa

Mine I left at default cos I don't need a fast zoom..at the very worst case scenario if I forget to frame a shot I need to creep the zoom so it's not so noticeable. So zoom is on variable and speed is at 16 ...it's a little slow for most but OK for me!! Now, the Panasonics have a ramp speed at start and end so the zoom never stops but slows down gradually.... Try your cam at variable and speed 16 ..it might be OK ...a high speed setting might make it behave differently??

Hope yours is OK nevertheless!! I'll also test the 2nd camera when it arrives in a few days.

Chris

Peter Rush February 27th, 2013 03:03 AM

Re: Zoom problem
 
Mine does this - it's as if it's taking up some slack at the start of the zoom and letting it go again at the end! I use zooms for establishing shots/architecture at wedding venues so is a real problem for me

I got in touch with CVP who i bought the camera from and they told me to get in touch with Sony Prime Support which I intend to do soon

Noa Put February 27th, 2013 04:56 AM

Re: Zoom problem
 
Pls let us know how that turns out Peter, to me it looks like a general problem as quite a lot users have reported the problem so far so they might benefit from the outcome you get as well. I checked it again yesterday and you see the lens pulling to the left at the start of a zoom.

Peter Rush February 27th, 2013 05:27 AM

Re: Zoom problem
 
It definitely pulls at the start of the zoom - every time!!

I will get in touch with Sony Prime Support today but then I'm on holiday for a week so will post their response when I get back

Pete

Christopher Young February 27th, 2013 10:42 AM

Re: Zoom problem
 
Quote:

Originally Posted by Noa Put (Post 1778447)
has anyone else noticed this problem on their camera s well?

What you have demonstrated is something I have seen on the original SEL-18/200 kit lens that comes with the FS700. Seen it on three different cameras, mine included.

I believe all Sony cameras using this lens and its varients will exhibit the same behaviour. The EA50 uses the same lens basically but adapted to run with a power servo, the SELP variant. What you are showing is what I expected from this lens. Seeing that the lens is varifocal and not parfocal I guess that's part of the problem. I also guess that's why these lenses have such a glacially slow zoom speed, to allow the autofocus to track and keep up with the zoom speed. They appear to go out of focus just as you start the zoom, as though the autofocus has just woken up to the fact that it has a job to do.

In short I don't think there is anything wrong with the lens as such. AFAIK this lens design was for the NEX cameras for stills work where varifocal is not an issue. I think the only way around it for video is to not shoot and zoom at the same time. Very frustrating when you have been used to zooming with true parfocal Fuji and Canon broadcast lenses.

Chris Young
CYV Productions
Sydney

Rod Pike February 27th, 2013 06:48 PM

Re: Zoom problem
 
Quote:

Originally Posted by Peter Rush (Post 1781346)
Mine does this - it's as if it's taking up some slack at the start of the zoom and letting it go again at the end! I use zooms for establishing shots/architecture at wedding venues so is a real problem for me

I got in touch with CVP who i bought the camera from and they told me to get in touch with Sony Prime Support which I intend to do soon

Peter, does it do this jump at the start and stop of the zoom at any zoom speed? if so does it make a slow creep impossible other than in manual?
Rod

Christopher Young February 27th, 2013 09:13 PM

Re: Zoom problem
 
Rod ~

I don't know what Peter's experience is but in my experience the these lenses dip out of focus regardless of zoom speed or position. If in manual mode you follow the pretty common practice of zooming in, focusing and then zooming out... well that doesn't work as the lens goes out of focus. As is to be expected with a varifocal design.

In manual mode. Lets say you are on the wider end of the lens and you use the momentary auto focus button to focus on a subject then zoom in the image is well and truly out of focus. Press the momentary focus button again and the lens quickly and generally will re-focus correctly. Zoom out again and it is now out of focus, although hard to tell on the small screen. Press the momentary focus button again and it will establish a new focus setting. Zoom back in and its out again. In auto focus mode do a very s-l-o-w zoom and you can just about keep it in focus. In daylight it's not too bad in low light with the lens wide open it most noticeable due to the lack of DOF.

This being the case means that in full auto focus mode the lens is going to have to track the focus changes when you zoom. IMHO that's what you have to expect with this type of lens design.

Chris Young
CYV Productions
Sydney

Wacharapong Chiowanich February 27th, 2013 09:29 PM

Re: Zoom problem
 
Same problem on a VG30 body I tried recently. My guess is the jerky zooming mechanism fooled the AF system into refocusing, assuming there had been slight movement in the already in-focus subject when in fact there had not. Maybe the encoder was fooled as well by the lateral shift of the subject but I couldn't tell.

Coming from using ENG cameras and later several Handycams from the lowly consumer HDR-CX series up to the EX1R I have to say the PZ zoom lens is very disappointing, to say the least.

Rod Pike February 27th, 2013 09:52 PM

Re: Zoom problem
 
Quote:

Originally Posted by Christopher Young (Post 1781502)
Rod ~

I don't know what Peter's experience is but in my experience the these lenses dip out of focus regardless of zoom speed or position. If in manual mode you follow the pretty common practice of zooming in, focusing and then zooming out... well that doesn't work as the lens goes out of focus. As is to be expected with a varifocal design.

Chris Young
CYV Productions
Sydney

Thanks Chris, but my question was probably not concise enough : It was not the auto focus that concerned me.
In that video there appears to be a lateral image movement both at the start and finish. I also see the search for focus going on and understand that.
I was more interested in this apparent lateral movement- or is it just an effect of focus hunting?

More importantly does it have this characteristic in manual focus/power zoom, or is it only in auto focus mode?
(I ask as a potential purchaser and this forum is a fab testing ground and is slowly helping me come to a decision).
EDIT: I missed Chris Harding's test results which are not showing this problem, so it looks like a lens/servo issue maybe?
Cheers!
Rod

Chris Harding February 27th, 2013 11:11 PM

Re: Zoom problem
 
Hi Rod

I never have done a zoom test at all...I don't seem to have a lens issue on either camera, probably due to the way I shoot ...I use my zoom for pre-shot framing 99% of the time and the problem has never come up on the very rare time I do zoom. I'm sure both my lenses have the problem but with my style it never shows.

Chris

Rod Pike February 28th, 2013 12:43 AM

Re: Zoom problem
 
Hi Chris, as you see I am still lurking! I must have misread your post, I thought you had auto zoomed for a trial- my bad as they say.

So , does that not make a creep zoom impossible other than in manual mode? you have to start and stop at some point and with this "kick" it would be impossible. I would not be able to work like that with a lot of my corporate stuff- a slow smooth creep is essential for me.. That's one thing my 160A does very nicely with the varizoom controller hooked up-syrup smooth)

Any further input from other 50 users? have you got a "kick" on zoom start/stop, and does it happen in auto and manual focus?

Cheers!
Rod


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