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-   Sony HVR-Z1 / HDR-FX1 (https://www.dvinfo.net/forum/sony-hvr-z1-hdr-fx1/)
-   -   Focus on the Z1 (https://www.dvinfo.net/forum/sony-hvr-z1-hdr-fx1/115853-focus-z1.html)

Simon Denny February 27th, 2008 02:18 AM

Focus on the Z1
 
I'm filming a job at the moment and it's cotton farming from seeding to harvest time.
I spent two days shooting just getting a feel for the farm and getting ground shots of the crop. When i was shooting i thought yep everything is in focus my pans looked good etc.
When i got home all excited about what i got,i found most of it is out of focus.
I cant beleive how hard it is to focus on large crops,dams and panning, just as well interviews havent started yet.
Has Anyone had to film a large area of crops with a pan and keep it all in focus?
The old trick of zoom in focus, pull out wont work on this one.

Regards
Simon

John M. McCloskey February 27th, 2008 08:51 AM

Have you tried using the peaking option. You can change the color also to a color that is opposite of your subject matter. I have also noticed with our Z1's(yes all of them) when you focus to infinity and pull wide it doesnt acheive focus. Seems like you must go a tad bit forward from infinity to acheive full focus when pulled fully wide. Also if your camera is in steadycam mode when panning it is easy to see the floating image issue which sometimes makes things look out of focus.

Simon Denny February 27th, 2008 01:45 PM

Thanks John,
I'm exploring the peaking option and will do some tests.
I think very slow pans keeping focus on whats just in front of me and using the Exp focus button and then lock it down into manual.
I have been using auto focus on msot wide shots thinking this will do but how wrong i was. This camera really needs to be on focus as a bit out it shows up on large widescreen TV's.
I wonder if shooting in SD would have this problem?

Cheers
Simon

John M. McCloskey February 27th, 2008 01:53 PM

Oh yeah in auto focus panning or videoing moving objects you will always have problems.

Simon Denny February 28th, 2008 04:46 AM

I have just gone back a reviewed what i shot.
Camera out, to a Samsung LCD TV.
Looking at raw footage from the camera all is in focus but some of the long pans and a few close up shots.
Fine
I have down converted from camera to Sony Vegas and after viewing all footage shot everything is blured.
I'm thinking it's a Vegas problem or a drive. How will i work this one out?

So i'm glad its not the camera or me the operator, i was starting to freak out that my footage was out of focus and had to go back and film.

Regards
Simon

John M. McCloskey February 28th, 2008 09:18 AM

One thing I have heard a bunch with HDV footage is shoot HDV, Edit HDV, then master in SD. If you are bringing your footage into your NLE in DV25 and not 1 to 1 or 1 to 2, its gonna look very fuzzy. From what I have heard in DV 25 you loose at least 60 % of your HDV true look.

Simon Denny February 28th, 2008 01:47 PM

yes it seems by down converting in camera and then editing in SD i'm taking a resoultion hit and everything as you say looks very fuzzy,blured.
I cant have this happen, the client will freak if they see this.
Even capturing in HD and play back there seems to be a resoultion hit.
I will keep testing and see if a soultion is around?

Simon

John M. McCloskey February 28th, 2008 03:31 PM

You have possibly heard of this, http://www.convergent-design.com/CD_...DConnectSI.htm it is a wonderful tool, check out the video that shows the differnce in this link.

Simon Denny February 29th, 2008 11:46 PM

Thanks John,
Looks interesting.

Matt Davis March 3rd, 2008 01:03 PM

Quote:

Originally Posted by Simon Ash (Post 834747)
yes it seems by down converting in camera and then editing in SD i'm taking a resoultion hit and everything as you say looks very fuzzy,blured.

A couple of things that may allay your fears, but they're Mac/FCP things:

QuickTime DV movies are, by default, shown in half-rez mode. You need to open each movie in QT Player, select Movie Options (Cmd-J) and select High Quality checkbox (bottom right) in the video tab.

The in-camera down-convert isn't actually that bad. It's as good as the 'average to good' option in Final Cut Pro. There is, however, a bit of a trade off using the in-camera sharpening mode (Sharpness in the Z1 goes from 0-15, factory preset to 12, which makes quite big ugly lines round areas of high contrast). If you wind this down to about 8-10, the HDV image looks really quite soft, and the SD image softer still.

The trick is to shoot around Sharpness 9-11 in HDV, edit, and then in the downconvert, add sharpening from your NLE - just a tiny smidge. Not much (in my FCP setup it's about 5-7%). It seems that the sharpening is done at SD scale but uses the information from the HD scale.

What it does do is make the footage look like it was filmed with expensive glass on an SD camera.

But OTOH, I've had one Z1 that didn't have good back-focus (zooming in to focus, pulling out to shoot DID NOT work), and my current Z1 is good for back-focus but continues to frustrate even with peaking turned on.

I would rigorously test your Z1 for back-focus, and if it's not right and within warranty, ask Sony to fix it. If it is right, use the focus marks in-viewfinder to note the distances for certain spots.

In my experience, the Z7 and EX-1 are significantly easier to focus on the LCD screen. The Z1 screen is good, but it isn't THAT good. :)

Simon Denny March 3rd, 2008 01:22 PM

Intersting Matt,
I did try sharpening in Sony Vegas but that was with dowconverted footage.
I will more tests this time with HD converted to SD.
The HD image from the Z1 is great but downconverted its so soft and fuzzy i dont like but what can you do?
I'll give your idea a go.

Regards
Simon

Matt Davis March 3rd, 2008 03:37 PM

Quote:

Originally Posted by Simon Ash (Post 836766)
The HD image from the Z1 is great but downconverted its so soft and fuzzy i dont like but what can you do?

This is kinda interesting. Not sure if I like the pattern that's developing.

Many people agree that the Z1 HDV image is pleasing. A worryingly large subset is saying 'HDV to SD doesn't look good'.

In my world of HDV users using FCP, we're Cheshire Cats, we're happy with HDV - hey, if we were filming snowboarders or rally cars, we'd complain, but on the average Corporate shoot, it's okay.

The trick comes when we downsample to SD and add 7% sharpening - which is when Z1 looks like DSR-570 with $10k+ of glass up front. I don't think this step is happening as it should for other users.

Simon Denny March 5th, 2008 04:32 AM

Hi Matt,
Thanks for the good response i do appericate it.
What do you mean by back-focus? I have heard others talk about this but have never followed it any further.

Regards
Simon

Matt Davis March 5th, 2008 04:52 PM

Quote:

Originally Posted by Simon Ash (Post 837617)
What do you mean by back-focus? I have heard others talk about this but have never followed it any further.

With removable lenses, there's a critical adjustment to check/make which shifts the lens fore and aft to ensure that as you zoom in and out, the focus remains the same. Zoom in, focus, zoom out, twiddle the BACK focus ring until it's sharp. Best done with an external monitor or a very good pro ENG viewfinder.

Fixed lens cameras with motorized zooms tend to have fixed back focus or, like the EX-1, a hidden service-menu item to perform an internal back-focus check.

You can download a focus chart from the web (google 'back focus chart'), print it out as big as you can, stick it to a wall and place the camera 3-6 yards away (longer is better IIRC). Zoom in, focus, pull out and look for signs of softening. Don't forget the expanded focus button! :)

One thing I'll mention in passing: the Z1 lens's sweet-spot is between f2.8 and f4 - if it's wide open, you're using all of the glass, not the best bits. Beyond f5.6, 'there be dragons'. F8 to f11, you will notice diffusion, as if the camera has got fogged inside. Not nice.

Simon Denny March 6th, 2008 12:49 AM

Hey Matt,
Can you explain, Z1 lens's sweet-spot is between f2.8 and f4 - if it's wide open, you're using all of the glass, not the best bits?

I allways try for a mid spot on the iris around f4 if i can get it. What about focal length?

Simon


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