DV Info Net

DV Info Net (https://www.dvinfo.net/forum/)
-   Sony HVR-Z5 / HDR-FX1000 (https://www.dvinfo.net/forum/sony-hvr-z5-hdr-fx1000/)
-   -   Does the Z5 have a focus problem or not? (https://www.dvinfo.net/forum/sony-hvr-z5-hdr-fx1000/481637-does-z5-have-focus-problem-not.html)

Les Wilson July 9th, 2010 06:08 PM

Does the Z5 have a focus problem or not?
 
I'm loath to return to gibberish Sony manuals and denials of problems but I'm finding the Canon tapeless acquisition products going in a direction that doesn't suit me or my budget. So, I'm considering going back to Sony and I'm looking first at the Z5 because I already have an MRC1 and I like the HDV workflow over AVCHD.

I've read back 7 pages of this camera's postings, watched every You Tube video I could find and analyzed the Z5, Z7, EX1 and NX5 more than a person should. But I can't tell if this camera has a focus problem or the same as other ones in it's class. Postings that say "well it's a pro-camera and you should learn to focus manually" are a warning sign and make me think it has a very real problem that will affect my use of the camera.

So I tried to simulate the indoor "arggg it won't focus on the face closeup" problem in my studio and then ran the XH-A1 against it. Can I interest someone to recreate a similar environment and test a Z5? Or, if there's another situation to test, lay it out and I'll test the A1 against it.

As noted in the text graphics of the video, I used the Canon in the auto exposure mode that keeps the shutter fixed and varies the aperture to best expose the frame. I zoomed in to 85% on the A1 20x lens which made sure each subject I panned to was not in the DOF of the prior subject. I tested both auto focus modes. All I did was to pan the camera to the three points. You'll note that in normal mode, the A1 took an exceedingly long time to focus on the poor contrasting towel but it eventually did focus.

Here's the A1 results:

Dave Burckhard July 10th, 2010 09:19 AM

Hey Les,

To clarify, posts that suggest that one focus manually don't necessarily mean the camera doesn't perform its auto-focus function admirably. Focusing manually only means that you assure that your plane of focus is determined by you and not the camera. For instance, if your subject that you want to be in focus is an off-center, small, dimly lit, low-contrast object in the foreground and the background is a bright, high contrast object, auto-focus will work fabulously in focusing on the background and not focusing on your subject. That's an extreme case but makes a point. Surely, you've seen a myriad of photographs that are "blurry" when taken by amateurs shooting in AF mode. However, you'll probably find a bright high contrast object in perfect focus somewhere in the photograph. Indeed, AF worked perfectly.

Modern AF systems work great and, in some cases, have some intelligence where they might recognize a face and bias its focus on the face. Cool. Such systems, though, have limitations and simply can't read the camera operator's mind.

The auto-focus system on the Z5 works nicely and quickly in many cases. I've tested it and am impressed with its capability. However, I tend to focus manually to assure my subject stays in focus and continues to be in focus even if something comes between the camera and the subject or an object in the background shows up that may become the object of desire of any AF focus point hunt.

I would have no hesitation in a run and gun situation to use AF, such as a breaking ENG event where I'm spending most of my time simply stabilizing my camera and framing while moving. Even so, I'd be aware of my subject (an interviewer, a moving vehicle, etc.) and try to keep it large in the frame so as to assist the AF system.

As a side note, I want to point out an advantage of a fixed lens system over those with interchangeable lenses. An issue every interchangeable lens camera has is that with "back focus." It's not a fault but, rather, a feature of such cameras that if they are not adjusted properly after a lens change, the focus plane can shift when zooming. This doesn't happen with the lens on the Z5. On interchangeable lens cameras, I've heard of complaints of blurriness in manual focus resulting from the technique most of us use in focusing. That is, we zoom in close on a subject to focus and then zoom out to frame the shot. That act of zooming, if the back focus adjustment is off, will change the plane of focus and result in a blurry shot. In that case, AF may actually be a preferred mode in harried cases when there's no time for back focus adjustment.

It's wise that you put utmost consideration in your workflow over specific features of cameras. Don't discount the Z5 for any focusing issues. Rather, whatever you get, test the behavior of the AF system, learn it, and shoot accordingly.

Dave

Les Wilson July 10th, 2010 10:33 AM

Thanks Dave. In reading pretty much every post on this issue, there was a clear trend by some to dismiss those who depend on AF for whatever reason...run and gun is one...another is not being able to see focus in the VF or LCD... anyone who does this craft solo knows there's times you have to go with AF... I've had zero problems with the A1 AF in every situation I've chosen to depend on it.

I'm familiar with back-focus from my XL1s years and very much appreciated the advances in AF after the move to the XH-A1 especially since it's so important in HD.

Granted, reading posts can provide an inaccurate picture (pardon the pun) but in considering a move to a Z5, I thought it was significant to raise and get clarification on. The AF has to be capable for the basic situations I need it in (such as the one in my test and) and what I was reading in the discussions was a concern... shooters have sold the Z5 for the AF reason alone... Add to that the absurd menu button/wheel and you end up with a camera that has a bunch of high frequency irritations and potentially times it fails.

It's a concern to me to read several shooters mention they move to close ups on faces and the camera won't focus.

Mark Andersson July 10th, 2010 03:33 PM

Les,

I find AF on the Z5 90% spot on. I also suggest to use AF Override (AF Assist) if the AF doesnt lock on to where you want you can tweak it.

Also keep your Macro OFF.

Rob Morse July 10th, 2010 07:53 PM

There are situations and environments where it is best to shoot in manual mode and it would be the same for any camera. I really use manual mode most when I'm locked down. What's the point of being in auto? I feel the Z5 has made me a better shooter.

I wish I had the time to do the same test you did above. Just looking at it, I don't have a problem like that with the Z5.

Rodolfo Cintra July 10th, 2010 09:10 PM

Quote:

Originally Posted by Mark Andersson (Post 1547207)
Also keep your Macro OFF.

Why?
Why should I disable?
Thank you.

Mark Andersson July 11th, 2010 12:56 AM

Hi Rodolfo,

is good to enable Macro when u want to do macro shots but it can get you into trouble. So for general shooting i.e when you zoom into a subject lock focus and then zoom out, with macro enabled the camera can lose its focus. Its just a cautionary thing.

Les Wilson July 11th, 2010 05:40 AM

I went back and searched...these are a couple of the posts I was talking about...these are just the negatives
Example 1:
http://www.dvinfo.net/forum/sony-hvr...-problems.html

The poster was coming from a fast autofocussing V1 using a Z5 in the same conditions:
The big negative so far is the fact that the camera is intermittently searching for focus whilst shooting at night under strong lighting.

Responses:
I never ever use auto-focus and wouldn't recommend anybody to do so unless they wanted that auto-focus video camera look.

This issue you describe is the same with the FX1000 and something that does not endear the camera to me, among other things.

I agree with Jeff and Justin, learn to use the manual focus.

...bottom line, unfortunately you will need to adjust your shooting technique and put more work into using the camera to get the images you want.

I was a little disappointed with the Z5 auto focus as well but now I shoot much more in manual.

...the slow focus issue might be a CMOS issue

End of the story:
thanks for the advice and email too guys. Gonna sell it

Example 2:
http://www.dvinfo.net/forum/sony-hvr...detection.html
It seems these cams just don't like faces in the autofocus mode. In fact, I can't recall ever having a camera that had such a tough time with faces. More often than not the camera seems to prefer to focus on the background and ignore the face. ...focusing on a face that filled up 70% of the frame and the cam still refused to focus on the face.

Responses:
This is a normal problem with digital passive auto-focus systems.

You guys are absolutely right about the autofocus, My FX1000 does it too. Its perfect outside but inside where the background is a bit overexposed compared to a face, it focus on the background

I have to agree. My Z5 was used to shoot a ballroom dance. The lighting wasn't great but still exposed ok. But many times I found the camera losing focus and then struggling to get it back. Very unimpressive performance.

Leslie Wand July 11th, 2010 07:00 AM

well, i tend to agree that the auto focus isn't the bees knees of af in general.... but then again, i spent most of my professional life shooting with cameras that didn't have af in the first place, so i find any af better than no af, and that on the z5 quite acceptable - when i use it.

(little rant on)
i'm really not sure what people expect from a 'pro' camera any more. to knock a perfectly good camera because it wont focus quickly enough strikes me as being a somewhat lazy attitude to shooting. and complaints of problems in low light, well, i find that even more strange. what do people expect, infra red, night sight?
sure my 170 could probably have picked out a black cat in a dark room, but why would i have want to in the first place perplexes me. if the lighting is bad, on say a bridal waltz, then either get an on camera light, have them turn up the house lights, or get in close on wa and use a moderate degree of gain - i mean people understand 'noise', it's what happens when you shot video in low light!!!
in 5 years all this generation of camcorders will look like tonka toys anyway, so if you're really concerned (btw les, this isn't directed at you personally!), hang on for the next generation of cmos or whatever they develop - or buy a camera now that meets your af expectations - but if you're going to buy a camera based on af, you've got a lot more to learn about shooting video....
(rant off)

Les Wilson July 11th, 2010 11:24 AM

I agree with you. I'm pretty sure you weren't directing the rant to me but to be clear, I'm not purchasing a camera based on AF. I look at virtually all aspects and assess it as a whole against my needs. In this case, I started this thread to get a better picture of the impact of the AF issue I was reading about. You and the others have done that nicely and I'm not worried about it (anymore); lousy ergonomics, cheap buttons and frequently used functions buried in menus? Yes, AF? No.

It would still be nice to A-B the cameras and test the assertion that they're all the same in class but the thought out responses shared here make me think the Z5 AF is good enough that I'll spend the time and money to rent one or something.

Rob Morse July 11th, 2010 05:43 PM

I don't think you can compare the Z5 to the PD-170 because it is not HD. I believe that is part of the cause with auto focus. The 170 was a great camera but there is always give and take in a new camera. If one camera did what everyone wanted we wouldn't have so many cameras. Les, look up all the good features of the camera.

Chris Duczynski July 12th, 2010 04:35 AM

I find the main problem with trusting manual focus outside is that the LCD in daylight is hard to see - even with a shade screen.
I was bought up on viewfinders (as in eyepieces) that shield all light and your eye is right there close. The eyepiece viewer on the Z5 is pretty poor so if you have moving action like someone running towards you it's impossible to follow focus - Auto works great.
Agree about faces under lights with AF with the continual slight readjusting every time the head moves slightly. Also be very careful using detail to soften skintones - very tricky to get it right.

Leslie Wand July 12th, 2010 06:03 AM

i honestly can't remember the last time i used the lcd - nice for 'general' shooting, but nothing beats looking through the eye piece - and i beg to differ chris, i think the eyepiece is pretty damn good on the z5, and combined with using the extended focus button, pretty near infallible....

Jeff Harper July 12th, 2010 06:04 PM

There is nothing wrong with the autofocus on the camera. I cannot beleive this. The focus wanders in DIM lighting, so what? It is amazing how long this camera has been out and this is still up for debate.

Zach Love July 27th, 2010 10:15 AM

I don't want to sound like a snob, but in my opinion professionals tell their gear what they want, they don't let their gear tell them what they want.

How many Nascar drivers drive an automatic on the race track?

The Z5 has a 4.1mm-82mm lens. If you're at f/8 zoomed in all the way & trying to focus on something that you guess is 30' away, you have can be off by 10' & still have the object in focus.

In my opinion there are a lot of things that can come between my lens & my subject in 30', a lot of things that will excite the auto focus & get the camera to start hunting for something to focus on that I don't want it to focus on.

I own a Z7 & when I've heard people complaining about the auto-focus on the stock lens my reaction is "the only problem I see with the autofocus on my Z7 is that there is an autofocus."

But any camera, Z5 or whatever, is going to have a harder time auto focusing in lower light. As technology progesses technology will get better, but our cameras don't have a good AI, or the ability to read my mind. I like to rack focus & until there is a computer chip in my brain, there will never be an auto-rack-focus. But that is me & my style.


All times are GMT -6. The time now is 01:44 AM.

DV Info Net -- Real Names, Real People, Real Info!
1998-2024 The Digital Video Information Network