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-   -   GY-HD200U Focus Issue (https://www.dvinfo.net/forum/jvc-gy-hd-series-camera-systems/138955-gy-hd200u-focus-issue.html)

Ted Ramasola December 11th, 2008 02:53 AM

Quote:

Originally Posted by Akbar Ukani (Post 976078)
I had the same problem..Do this...

- On the lens you'll notice the word "Macro" with 2 vertical lines
- Right below the lines, there will be a little screw or knob
- Make sure that the two vertical lines are not off...they should be aligned with each other.
- If they are off, then loosen the screw and align them....also make sure that the Macro is not turned on

This is not entirely correct.

Please refer to your manual on setting your backfocus using a siemens star or a focus chart approx 3 meters away. A use of a reliable monitor is recommended.

Its not just a matter of "loosening the screw and aligning the lines".

Stuart Nimmo December 11th, 2008 09:09 AM

Ted's right, back focus is critical but you really shouldn't be having this trouble this camera is usually excellent.

With DV I would start with detail at normal and I wonder if your skin detail is properly set-up? I'd switch it off and have another go.

Tim Kelley December 18th, 2008 10:23 AM

Okay...follow-up to original question....I'm setting up for an indoor shoot. I've got a ton of light (too much probably) thrown at the interview set. The iris is cranked wide open. If it drop the gain to -6, it closes a little (2 to 2.8 in auto). However, the image is still WAY too dark. I'm using the preset in the camera so I've not tweaked anything other than the safe area being shown.
Still seemingly pulling my hair out trying to get this thing right. I would imagine that the focus issue could be linked to poor light pickup but not sure.
Understand this isn't point-shoot but I've never seen reactions out of a camera like this seemingly right out of the box.
White balance is in 3200K...
Any suggestions/thoughts? I'd hate to shoot and have to "fix" in post but I've got to do something as my other camera is down right now.

Shaun Roemich December 18th, 2008 10:50 AM

Is the shutter engaged? How about neutral density filters? Polarizer or ND filters in front of the lens? Any of these will decrease the amount of light hitting the imager.

Tim Kelley December 18th, 2008 11:16 AM

Shaun...Shutter is OFF, ND filter OFF, no filters on the lens. I've shot outside with no realy issue like this and with ND1 on. That's what is puzzling to me about this setup. I have a loaner lens from the JVC rep right with mine due in this afternoon. I doubt that will alter anything but I've got to figure it's something with the camera settings and/or in general that I'm missing completely.

Tim Dashwood December 18th, 2008 11:53 AM

Quote:

Originally Posted by Tim Kelley (Post 980293)
Okay...follow-up to original question....I'm setting up for an indoor shoot. I've got a ton of light (too much probably) thrown at the interview set. The iris is cranked wide open. If it drop the gain to -6, it closes a little (2 to 2.8 in auto). However, the image is still WAY too dark. I'm using the preset in the camera so I've not tweaked anything other than the safe area being shown.

There are a few basic issues here.
  1. There is no such thing as "too much light" on any indoor set. You can always compensate with iris, shutter or ND filters to reduce the light entering the sensor.
  2. There is no negative gain available on the ProHD cameras. You have increased your gain to +6dB, hence increasing the sensitivity by about 2/3 of a stop, but also adding video noise. For the cleanest image leave the gain on 0dB.
  3. It sounds like you are relying on auto iris to determine your exposure and it is consistently too dark for your liking. You have tried to compensate by adding gain, but the camera just closed down the iris to give you the same exposure. You could crank it to +18dB and the iris will continue to close down to give you the same exposure.
    If you don't want to set your exposure manually (M/A switch on lens) then you can adjust the preferred auto-exposure level in CAMERA OPERATION --> AE LEVEL. Positive values will give you brighter auto exposure levels. Try +2 and see how you like it.
  4. The auto-exposure uses averaging of light levels in the scene to determine exposure. However, if you have a "hot spot" in the set (or interviewee backlit by a window) it can throw things off and the AE may try to iris down to compensate.
  5. If you are still unhappy with the exposure after trying the suggestions above then go into the ADVANCED menu and try an alternate gamma curve and/or increase the gamma to shift the sensitivity in the mid-range.

This has gone off topic a bit but did you ever solve your back-focus issue?

Tim Kelley December 18th, 2008 12:32 PM

Tim...as for the focus issue...I'm not sure...By saying that...the image appears to be less soft with the detail now adjusted to normal from the previous MIN setting. However, it's tough in some regards to really tell as the darker issue could be "clouding" the result. I was wide on an outdoor parade shoot so it was tough to pickup on softness as much as it had been with previous tapings where I was in close.
The shoot I'm working on between responses calls for tighter shots mixed with wide. The result appears to be better. The only real adjustment was the detail setting.
Sorry about the -6 db...you are right...+6...
I had been trying to use manual IRIS but since it was maxed out anyway with darker than preferred amounts I just went to AUTO. You are right about adjusting the gain as it really doesn't make that much of a difference...slight but not overkill for what I'm seeing.
As for the AE level...it's on NORMAL right now.
As for the GAMMA, it's on standard with NORMAL level.
Black is also set at NORMAL with the stretch level at 4 as well as the compress level at 4.
Skin detail is ON at -2.
Master black is -3, detail is normal as is V/H. Not sure if any of these settings indicate anything at the moment.
The Sony DSR 250 I had before seemed to operate fine under these exact settings with lighting and locations. I'm still learning what's what with this camera. I like the colors but find everything is darker than I prefer and there is/was the issue with the softness in output.
I've quit using the Focus Assist and just go naked-eye in an effort to see what's what without factoring any other option/viewpoint into it.
THanks again for the information. I'm going to try your suggestions and see where that leaves me.

Tim Kelley December 18th, 2008 12:42 PM

UPDATE....I tried the AE adjustment while in Auto Iris...I didn't see any change in the view finder by moving anywhere off NORMAl...I tried up to +3 and down to -3 with no change in what I was seeing.

I did adjust the Gamma Level to +4. That seemed to help and I'm going to try that setup and see how it goes with brightness. The IRIS is still at 1.4 (# might be wrong) but it's one step below OPEN. It seems to teeter between 1.4 and OPEN.

Dennis Robinson December 18th, 2008 05:14 PM

Quote:

Originally Posted by Tim Kelley (Post 980332)
Shaun...Shutter is OFF, ND filter OFF, no filters on the lens. I've shot outside with no realy issue like this and with ND1 on. That's what is puzzling to me about this setup. I have a loaner lens from the JVC rep right with mine due in this afternoon. I doubt that will alter anything but I've got to figure it's something with the camera settings and/or in general that I'm missing completely.

Of course there is something wrong with the camera. Take it back. Even if you do use auto iris it is still able to get enough light.

Alex Humphrey December 18th, 2008 05:56 PM

loath to add to the confusion/help.
 
Well loath to add to the confusion after better people than I have helped. but here are my 2 cents worth.... It's review I know, but just in case I add something the anyone may have missed or forgotten about....

1. I check backfocus about once a month or before every paid project. focus-star at least 12 feet preferably farther from camera. Live output to a 32" or larger HD monitor. Keep the light as low as possible (ND1 or 2 if necissary... yes I know I can't spell) to keep the aperture wide OPEN to narrow the depth of field as much as possible. Zoom all the way in, focus, zooming back watching the center 1" of my field of view on my 32" HD monitor looking for the moir pattern, set backfocus. Repeat at least 4 times because I'm obsessive compulsive. Chain link fence across the street is also a good choice if you lost your star.. just open the window so the muck on the window doesn't confuse the issue. I have a 16x (everyone laugh now) and with all lenses, (especially the 16x, que the laugh track) they are alway softer full wide (except maybe the 13x, that lens simply rocks) and it's much more noticable in HD than SD.

2. Forgive this statement. With SD, focus is an after thought since a medium aperature will pretty much have everything in focus at most focal rangers and with SD who can tell except at full tele on the lens anyway..... HD is having to be serious about where you focus again. For a wide shot, pick a spot at the bottom of inside your rame, focus, pan up, shoot. OR if you don't have time.... the old rule was (with a med wide/wide shot) focus set at 5 feet. Aperture 5.6. Shoot. (the 16x lens pick 4.5f) If you have time, focus on your subject. Of course medium/tight, different story, zoom in, focus, zoom out to medium shot.

3. Master Black -3? I've moved back to Master-Black normal from -1. This really helped out in low light situations. I also keep Edge Enhancements at Normal or -3 for natural environments for snappyness, but around man made objects/straight lines (or close ups of peopel's faces) about MIN or -8.

I wouldn't put much faith in specific menue settings from the Sony line to the JVC line. I would start over at factory defaults and move from there, though defaults from both will be fairly similar of course.

Tim Kelley December 19th, 2008 08:19 AM

I've since made these changes:
Master Black: Normal

Detail: Normal

Black: Normal

Gamma: Standard

Gamma Level: 2

The thing is, under typical room lighting, my iris is still hovering (on Auto) between 2-2.8. Don't know if this indicates anything to anyone with regard to this.
Thanks again to all for the assistance and advice.

Shaun Roemich December 19th, 2008 09:54 AM

Ok, REALLY dumb question: have you used zebra to confirm that you are in fact dark and it's not just a really dark LCD and/or viewfinder?

Tim Kelley December 19th, 2008 03:11 PM

Shaun, as I'm learning...nothing is a dumb question.
yes....when I look at everything on my editor...I'm seeing the same response as I'm seeing in the viewfinder while shooting. The Zebra is reading the areas of brightness but the whole image seems bumped down even though the iris is OPEN or very close to it.

Jeen de Vos December 20th, 2008 11:38 AM

Hi Tim and other ProHD users,

I too have to learn to use the HD201 camera. Coming from the Sony DSR400 (DVcam) the HD201 is a whole different game. Filming in low-light area's seems sometimes allmost impossible. I do a lot of broadcast-interview programs on location and even with my cameralight full open it's not very wise to take a few steps back. That results in having the iris full open wich makes the image look out of focus. Perhaps it's the stocklens that makes it worse. I'm thinking about buying the 13x3.5BRMU Fujinon, hoping it improves the sharpness and gives me extra light. Does anyone know if this makes a big differance?

I've also been trying some camera-settings lately. The TC3 by Paolo didn't seem to work on my cam. Colours were great at first glance but faces turned out much to red in the end. I tried the DSC CDM28 last week wich made faces look yellow. After colourgrading the image was great though. I really liked the look (caused by the stretched blacks?). I'm hoping to test some other Dash-settings very soon. Tips are always welcome! As I said, I mostly use the cam for interview-programs on location for television broadcast (PAL).

The masterblack at -1 also gives me the idea that it takes away some light. Is this correct? What is the idea about setting the masterblack at -1? Can I leave it on 'normal' while using some of the Scene File Recipes?

Greetings from Holland and best wishes for the coming days!

Jeen de Vos

Ted Ramasola December 20th, 2008 11:53 AM

Jeen,

The Paolo TC for the HD200 series is not good for the red spectrum.

Paolo nailed it though for the HD100.

For the HD200, however, which has newer AD chips I found Tim dashwood's superwide setting VERY good.

You may however change the black stretch settings to Normal or 1 if you want good blacks straight out. I however to use stretch 5 since most work i do i color grade in post.

The Stock lens have a lot of "quirks" which you must learn to avoid. For instance, avoid using f stops wider than 2.8. f 2 upwards to f1.4 to open will exhibit lateral ca. And as you suspected a rather soft image.

A friend of mine owns a 13x which he is selling, he hangs out here too, Eric Gulbransen sold me his HD200 with the 16x in addition to the HD100 we already have.

They said that using the 13x is like having a new camera! They say its performance is outstanding.

-1 masterblack darkens your dark areas a bit but not so much.

Avoid using gain if you can help it +9db is still acceptable though for me in some cases.

Ted


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