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-   -   locking manual controls (https://www.dvinfo.net/forum/jvc-gr-hd1u-jy-hd10u/36080-locking-manual-controls.html)

Patrick Jenkins December 8th, 2004 01:28 PM

locking manual controls
 
I know the HD1/HD10 don't offer much in the way of manual controls, but I'm wondering if anyone could help me with this.

All of the manual controls on the camera seem to be either/or functions. You can change the shutter speed OR the aperature, or you can forget about those and change the white balance, or you can manually set and lock the whitebalance and forget about anything else.

The manual controls (as everyone knows) are incredibly weak... but is there someway to be able to lock more than one feature at the same time? Locking the white balance so the color and exposure doesn't drift makes the camera much more usable than without (choose MWB in the white balance menu, then hold the exposure button down until you see the L to lock it). How can I lock a shutter speed while also locking the white balance? I know sspeed and aperture are either/or, but can I lock both the aperture and the white balance?

Troy Lamont December 9th, 2004 07:33 PM

You've already got it...
 
You've pretty much figured it out. There's really no way to do two at the same time. There was some speculation back in the beginning (like last year) that if you cycle through the aperature and shutter speed that you could get each one to lock, but I do believe it was disproved.

I think we got slightly shafted with what very obviously was a rush to market product. Seeing the features that the Sony has and at the same price range, JVC could have done a whole helluva lot better.

I'm starting to dislike some of the features of the JVC like the constantly hunting auto focus, although I'm starting to use manual focus more often. The blown out whites, chroma noise, etc, etc.

When the settings are right tho', the image is something wonderful, but it seems like there are too many variables not controllable up front for you to get 100% all the time. Especially for me because I'm using it as a general purpose camera.

Anyway, enough of my rant. Enjoy.

Troy

Heath McKnight December 9th, 2004 11:03 PM

I've lost money with my HD10--I only made a third back from my initial investment in the past 18 months.

heath

Christopher C. Murphy December 10th, 2004 07:34 AM

Heath, I broke about even on my HD10u...just barely.

Heath McKnight December 10th, 2004 10:09 AM

At least you sold it. I'm going to put it up on eBay next week, I think. I'll try here again.

heath

Ken Hodson December 10th, 2004 02:16 PM

Patrick, read some of the older posts on using a variable ND filters via two polorizers. Lock the shutter then then increase ND's to correct for exposure. Try to use a monitor (laptop/TV/ect..) as the built in LCD just doesn't show the exposure well enough. Try to under expose a little then learn how to correct in post. Find and use a good noise fixing software to help correct chroma noise. We also recommend an UltraCon to increase latitude. Don't give up. Learn the cam and you will be rewarded. It is capable of producing an amazing progressive image.

Bobby Arnold December 23rd, 2004 02:46 PM

One thing I've never seen or heard of for the JVC camera, is there a way to display both aperature and shutter speed when you are in either aperature or shutter priority? Maybe in the service menus? It would make it much easier to select the appropriate filters if both were displayed.

Ben Buie January 5th, 2005 01:47 AM

<<<-- Originally posted by Bobby Arnold : One thing I've never seen or heard of for the JVC camera, is there a way to display both aperature and shutter speed when you are in either aperature or shutter priority? Maybe in the service menus? It would make it much easier to select the appropriate filters if both were displayed. -->>>

No, but you can find out both values. We keep the camera locked at 1/60th, and use ND filters.

If you want to see the current aperture, switch to aperture priority and the initial value will be the last detected aperture. Then switch back to shutter-priority to shoot.

This is how we determine what filters to use.

Also, this camera is much more forgiving on the high end than the low. Do NOT underexpose with this camera, a typical DV trick. Go for as close to perfect exposure as possible, and err on the side of being slightly too bright if you have to. It is easier to correct for too bright in post, don't have to worry about noise.

Still, you can't have enough ND outdoors on a sunny day (especially without a butterfly scrim). We shot some stuff outdoors with (3) .6 ND filters :) It actually turned out really nice, looks a lot like Super16.

Another helpful hint, when you are shooting outdoors on a really sunny day, the camera has a tendency to have a green shift. You will likely have to bring down the green channel level by 10% in post (use the Levels filter in Vegas, it is easy).

Oh yeah, one more thing. This camera has more than paid for itself with us. We completed around $15k in projects in 6 months last year with it. The funny thing is, we never bought it, so I guess we came out extremely well. In my opinion buying a camera is extremely risky these days, with things changing as fast as they are. If you are producing work for pay, it is much more cost-effective to rent and build the cost into your project budget. Of course, if you are producing completely self-funded projects, then that is easier said than done.

Tom Roper January 5th, 2005 04:11 AM

<<<-- Originally posted by Ben Buie :
Still, you can't have enough ND outdoors on a sunny day (especially without a butterfly scrim). We shot some stuff outdoors with (3) .6 ND filters :) It actually turned out really nice, looks a lot like Super16.

Another helpful hint, when you are shooting outdoors on a really sunny day, the camera has a tendency to have a green shift. You will likely have to bring down the green channel level by 10% in post (use the Levels filter in Vegas, it is easy).

-->>>

No disrespect intended Ben, but the green shift is a consequence of too much ND filtering. Although I don't have the links, screen captures have been posted before that illustrate the green shift as ND filters are added. Basically what was shown, was that you can use ND to reduce exposure by up to about 3 f-stops without too much green penalty, but going beyond 3 f-stops causes the picture to take on a green cast. But using (3) .6 filters is 6 f-stops, or reducing light to 1/64! It's just too much for the CCD sensor, shifting it into a reciprocity failure, or where the green shift becomes very obvious. This is what you are correcting for in post with Vegas.

One of the CC filters in TMPGEnc 3.0 Express is CMYK Contrast White Base. By moving the K slider to the left on the order of about -15 on the scale, what you are doing is reducing the white contrast without overly impacting the mid-range, and no effect on the darks. It restores detail buried within the bright highlights, and reduces the white crush very effectively. If you use a contrast filter like THAT in post, that affects only the brighter areas and leaves the mid tones and darker areas alone, you can in some instances reduce your reliance on so much ND filtering, and further reduce the tendency toward a color shift. Perhaps there is such a filter in Vegas.

It's important to stay within the exposure and color latitude limits of the CCD, because the shift is non-linear, so a simple 10% reduction in green may have a penalty attached in other areas of the picture that were not green-shifted by the same percent.

So I think you CAN have too much ND in bright outdoor scenes. Panning, exposure latitude, mpeg encoding are just a few of the obstacles that get in the way of artistic, creative freedom. We do what we can to best operate within the constraints of the format, and it's not for me to argue the director's intent, if it's to correct a green color shift by a linear 10% in post, then so be it.

As a rule, I won't use more than .9 ND (3 f-stops). And using .9 ND, if I can't shoot at 1/60 without overexposing on a bright outdoor setting, the compromise I make is to increase shutter speed as necessary and try to minimize panning. It's unfortunate, yes...but it guards the color and exposure latitude that's so important to preserving the realism within a HD video.

Just my $0.02

Ben Buie January 5th, 2005 09:11 AM

<<<-- No disrespect intended Ben, -->>>

No disrespect taken, your input is welcome!

<<<-- but the green shift is a consequence of too much ND filtering. -->>>

Is it too much ND filtering, or just too much exposure latitude for the camera regardless of the ND used? Or is it a combination of too much ND and a lot of green in the scene (putting too much work on the separation ability of the 1-CCD system)? The randomness of seeing the green shift on bright outdoor scenes (using the same amount of ND or less) has somewhat puzzled me.

For example, we often see black shirts turning green on bright days, even without using ND.

<<<-- Although I don't have the links, screen captures have been posted before that illustrate the green shift as ND filters are added. Basically what was shown, was that you can use ND to reduce exposure by up to about 3 f-stops without too much green penalty, but going beyond 3 f-stops causes the picture to take on a green cast. But using (3) .6 filters is 6 f-stops, or reducing light to 1/64! It's just too much for the CCD sensor, shifting it into a reciprocity failure, or where the green shift becomes very obvious. This is what you are correcting for in post with Vegas.

One of the CC filters in TMPGEnc 3.0 Express is CMYK Contrast White Base. By moving the K slider to the left on the order of about -15 on the scale, what you are doing is reducing the white contrast without overly impacting the mid-range, and no effect on the darks. It restores detail buried within the bright highlights, and reduces the white crush very effectively. If you use a contrast filter like THAT in post, that affects only the brighter areas and leaves the mid tones and darker areas alone, you can in some instances reduce your reliance on so much ND filtering, and further reduce the tendency toward a color shift. Perhaps there is such a filter in Vegas.

It's important to stay within the exposure and color latitude limits of the CCD, because the shift is non-linear, so a simple 10% reduction in green may have a penalty attached in other areas of the picture that were not green-shifted by the same percent.

So I think you CAN have too much ND in bright outdoor scenes. Panning, exposure latitude, mpeg encoding are just a few of the obstacles that get in the way of artistic, creative freedom. We do what we can to best operate within the constraints of the format, and it's not for me to argue the director's intent, if it's to correct a green color shift by a linear 10% in post, then so be it.

As a rule, I won't use more than .9 ND (3 f-stops). And using .9 ND, if I can't shoot at 1/60 without overexposing on a bright outdoor setting, the compromise I make is to increase shutter speed as necessary and try to minimize panning. It's unfortunate, yes...but it guards the color and exposure latitude that's so important to preserving the realism within a HD video.

Just my $0.02 -->>>

Tom, thanks for this type of scientific input, again no offense taken at all. Those TMPGEnc tips are helpful as well. Next time we will play with the shutter speed and limit our ND at .9, and see if we can avoid the green-shift.

I guess it is all about what is acceptable to the viewer. I've been 95% happy with the results using a lot of ND and adjusting the green channel downward. Part of this is probably because we are so used to seeing a green pallette these days in TV and movies.

Also, I find it much harder to create a balanced look for the overall "film" when the camera operator (I should clarify I'm the producer and not the camera operator, although I'm intimate with the HD10) starts playing with the shutter speed. We can correct for color and brightness/contrast to get an acceptable look, but I find it hard to correct for shutter speed fluctuations. That, combined with a very small crew, time limitations, etc. has forced us to lock the shutter at 1/60th, use ND to get the exposure we want, and run with it. Probably not the best policy, but we work within our limitations.

Anyway, thanks again for your input Tom. Your posts (including your previous one about TMPGEnc over at AVS) have been extremely helpful. I agree I overstated when I said "you can't use too much ND" :)

Thanks again,

Ben

Tom Roper January 5th, 2005 12:52 PM

<<<-- Originally posted by Ben Buie :Also, I find it much harder to create a balanced look for the overall "film" when the camera operator (I should clarify I'm the producer and not the camera operator, although I'm intimate with the HD10) starts playing with the shutter speed. We can correct for color and brightness/contrast to get an acceptable look, but I find it hard to correct for shutter speed fluctuations. That, combined with a very small crew, time limitations, etc. has forced us to lock the shutter at 1/60th, use ND to get the exposure we want, and run with it. Probably not the best policy, but we work within our limitations.
-->>>

I have great respect, and totally appreciate the pragmatic realities you must deal with on the creative level, and the business level.

And I must concede some intimidation, take care and be thoughtful and considerate not to be construed as trying to lecture from a pundit's pulpit to a true pro who has much more experience in these matters.

So if you'll accept that disclaimer from me, I'd like to make an observation, that something unexplained seems very different in my result. Well I'm sure there's an explanation for it, I just don't know what it is.

But the shift I notice in bright outdoor scenes, is a tendency toward red highlights. It drives me crazy to see it in a blue sky, or in clouds that should be gray. But it's non-linear, so a simple shift in the red channel doesn't work. Instead, I reduce gamma in the red channel only.

So the point about that, is not to be suggesting you do the same, but rather to illustrate how ironic and unique some of these differing observations can be. Because that should tie in somewhere to an acknowledgement that just because we think we should be getting the same result because we are using JVC HDVs, the larger reality is there are all kinds of other variables at play, white balance calibrations, calibrations on the monitor, manufacturing tolerances, different lighting to name just a few.

I'm straying a bit, but another fellow was mentioning the two-polarizer trick, or poor man's ND. (I don't know about calling it that, good polarizers can be expensive.) But to an old film shutterbug like me who used polarizers to enhance his pictures, one thing about them seems very different for video than it was for film. When I used polarizers with film, to deepen a blue sky or reduce reflections on snow or water, it had the effect of deepening the color saturation. But on video, my observation is to be careful with them because I notice an undesirable tendency flatten the picture, and describing this subjective tendency is hard...but the effect can be to degrade the vividity <-- (if that's a word) of the scene if carried to the extreme, in this case more than about 3 f-stops.

Anyway, enough said by me. As always, thanks for your lucid and helpful posts and reviews.

Ben Buie January 5th, 2005 10:13 PM

Tom, don't sweat it. It sounds like you are much more experienced than I. If you aren't already a pro, you should be.

I really appreciate your input, because I lack some knowledge in the theory and scientific aspects of exposure, color correction, shutter speed, etc.

Thanks,

Ben

Patrick Jenkins January 7th, 2005 12:15 PM

Thanks for all the follow up info and insights!

I've actually got 2 HD10s and so far I'm really loving them. They aren't as flexible as one would like and it definitely requires a bit of thought and planning before using them, but these cameras have definitely earned their keep in my opinion.

I work for a public school system and I'm responsible for all of our video production (inhouse training, public access TV, etc) as well as all programming on our TV channel (broadcasting 24hrs/day). Nearly everything broadcast that was produced in house was shot with the JVCs in HDV, which then goes to Comcast in HD (I don't know the technical details unfortunately - not an engineer). Comcast sends us out in HD (as well as SD, but they handle that conversion internally). It's only a local (county) channel, but we're probably the first school system (K-12) that fully operates in HD.

While there's always going to be better stuff out there, considering the budget I had to get all of this going (less than a first year teachers salary), these cameras really have opened new doors for us in communicating to the students and community.

Carl Hamilton January 17th, 2005 08:30 PM

Hey Patrick! Since u love these cameras sooo much, u wanna buy mine? I hate it! I was one the early adopters who picked one up back in august '03 and was really excited about the prospect of shooting 16:9 and HDV, but the lack of manual control just kills it for me.

Ken Hodson January 17th, 2005 10:29 PM

Yes that cam has a strong learning curve, but I have found the results to be more than worth it. I would love to go with a different cam with more electronic manual control, but the lack of HD, progressive scan and lack of 16:9 just kills it for me.


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