View Full Version : HV20 manual exposure question


Phil Shima
April 15th, 2007, 08:22 PM
I haven't bought the HV20 yet - and have a question about how much control one has over manual exposure:

Can you manually override both the shutter and aperture? As an example, suppose you're shooting outdoors at night, and you want the exposure to remain unchanged - along comes a car with its bright headlights, which would change the overall exposure unless there was a manual setting. I've looked at the manual, but I don't see anything to confirm that it can be done - all I see is aperture or shutter priority - not shutter AND aperture.

Also, can one accurately manually focus in real time using the twirly dial?

John Hudson
April 15th, 2007, 08:37 PM
I haven't bought the HV20 yet - and have a question about how much control one has over manual exposure:

Can you manually override both the shutter and aperture? As an example, suppose you're shooting outdoors at night, and you want the exposure to remain unchanged - along comes a car with its bright headlights, which would change the overall exposure unless there was a manual setting. I've looked at the manual, but I don't see anything to confirm that it can be done - all I see is aperture or shutter priority - not shutter AND aperture.

Also, can one accurately manually focus in real time using the twirly dial?


Yes

You have the option of absolute control over Exposure.

Chris Barcellos
April 16th, 2007, 12:32 AM
Phil:

Essentialy what you do is slide the the control button on the right side of camera from auto to p.

Then you select menu. Under the P Menu, if you leave it in P, you adjust getting changes camera selects. It doesn't tell you what is changing. If you select TV, you get direct control over shutter speed, or Select AV which gives you direct control over aperature. There is also a Cine mode, which has limited adjustments, and there is also a specific set of scene selections (like snow, beach, etc....).

Once you select those, you use the toggle to turn on the exposure adjustments. Once you do that, things are locked. You can actually exit the exposure adjustment menu, but it will turn off the lock, when you hit the toggle again. Problem in the exposure adjustment is you don't know what is being adjusted (except that in TV mode or AV mode, shutter or Aperature is locked respectively.)

In all, there is a surprising amount of control for this camera. And after a brief introduction, it actually makes a lot of sense.

Ian G. Thompson
April 16th, 2007, 07:05 AM
Also, yes, you can accuratley focus in real time with the small focus wheel...problem is, especially with small LCDs, you will have a tough time. What is needed is a bigger screen (3rd party) to assist you with focusing. It's not like a focus ring where you use your thumb and middle finger (or index) together but in this case you are using just your thumb. Once you realize its limitations you get used to it quickly.

Wes Vasher
April 16th, 2007, 07:07 AM
Ian, have you tried the focus assist on the HV20? It rocks for focusing. I can find focus in about a second on my HV20 whereas it was virtually impossible to ever find focus on my DV camcorder without it.

Usually though I just hit the focus button to see if auto can find focus, then I hit manual focus and turn on focus assist to fine tune if needed. It basically makes having a tiny LCD irrelevant even when finding focus in HD.

Ken Ross
April 16th, 2007, 12:14 PM
Wes, you're 100% correct. I think many people miss the 'focus assist' on the Canon. Very nice pro-type feature.

Chris Barcellos
April 16th, 2007, 12:34 PM
Wes, you're 100% correct. I think many people miss the 'focus assist' on the Canon. Very nice pro-type feature.

Unfortunately, like with most of these assist features, you can't use it while recording.

Wes Vasher
April 16th, 2007, 12:42 PM
Unfortunately, like with most of these assist features, you can't use it while recording.

That's true Chris and kind of a bummer. I've really wanted to have focus assist while recording a handful of times already but it's not a deal killer. It's good to at least have it for setting up shots.

It would also be nice if we could zoom in and out and scroll around the focus assist function, kind of like how you can zoom and scroll around when you are playing back video or still images. That would be helpful.

John Hudson
April 16th, 2007, 12:48 PM
Unfortunately, like with most of these assist features, you can't use it while recording.

I suppose it depends on which camera is right and for who. For narrative film work all focus points shoud be figured out in advance anyway (a follow focus of course is always helpful).

For weddings or regular videography ? I wouldn't use an HVX.

Chris Barcellos
April 16th, 2007, 01:30 PM
I suppose it depends on which camera is right and for who. For narrative film work all focus points shoud be figured out in advance anyway (a follow focus of course is always helpful).

For weddings or regular videography ? I wouldn't use an HVX.

Actually, and I've said it before in other threads on this camera, the IAF is amazingly accurate, and should not be ignored an asset of this camera. You can center camera on subject with AIF on, then switch it off to maintain that focus. It will usually do as good or better than you can with the focus wheel.

Wes Vasher
April 16th, 2007, 01:44 PM
Actually, and I've said it before in other threads on this camera, the IAF is amazingly accurate, and should not be ignored an asset of this camera. You can center camera on subject with AIF on, then switch it off to maintain that focus. It will usually do as good or better than you can with the focus wheel.

Exactly. It's lightning quick too. It's rare that I don't at least start with AF.

I'm designing a little follow focus dial that I can mount on my HV20 with a button that'll depress the focus button because my big fat fingers don't work so well with the LCD location.

Chris Barcellos
April 16th, 2007, 02:45 PM
Exactly. It's lightning quick too. It's rare that I don't at least start with AF.

I'm designing a little follow focus dial that I can mount on my HV20 with a button that'll depress the focus button because my big fat fingers don't work so well with the LCD location.

You know, I was looking at that too. Hard to get at that dial for the button with the LCD open. My fingers are a little fat too.....:)

Jay Stebbins
April 16th, 2007, 03:29 PM
When adjusting exposure manually during TV mode. What is the best way to judge proper exposure. Should the Zebra Stripes be set to 70% or 100%? Then how much of the image should be striped?

Ken Hodson
April 16th, 2007, 03:30 PM
Phil:

Essentialy what you do is slide the the control button on the right side of camera from auto to p.

Then you select menu. Under the P Menu, if you leave it in P, you adjust getting changes camera selects. It doesn't tell you what is changing. If you select TV, you get direct control over shutter speed, or Select AV which gives you direct control over aperature. There is also a Cine mode, which has limited adjustments, and there is also a specific set of scene selections (like snow, beach, etc....).

Once you select those, you use the toggle to turn on the exposure adjustments. Once you do that, things are locked. You can actually exit the exposure adjustment menu, but it will turn off the lock, when you hit the toggle again. Problem in the exposure adjustment is you don't know what is being adjusted (except that in TV mode or AV mode, shutter or Aperature is locked respectively.)

In all, there is a surprising amount of control for this camera. And after a brief introduction, it actually makes a lot of sense.

Thanks for the explanation Chris, but maybe it's your choice of wording or my comprehension skills but I still don't have a full grasp the control aspect of this cam. Maybe a simpler question would be, as far as full manual control goes, what abilities is this cam lacking if it was to be compared to any of the prosumer cams.
Thanks.

Wes Vasher
April 16th, 2007, 03:35 PM
When adjusting exposure manually during TV mode. What is the best way to judge proper exposure. Should the Zebra Stripes be set to 70% or 100%? Then how much of the image should be striped?

That's a good question Jay. I don't know the answer but I set mine to 70% and usually click down exposure 1-2 clicks.

Chris Barcellos
April 16th, 2007, 04:38 PM
Try setting at 100 on zebras, then backing off till all but most highlighted areas, disappear.

Chris Barcellos
April 16th, 2007, 05:12 PM
Thanks for the explanation Chris, but maybe it's your choice of wording or my comprehension skills but I still don't have a full grasp the control aspect of this cam. Maybe a simpler question would be, as far as full manual control goes, what abilities is this cam lacking if it was to be compared to any of the prosumer cams.
Thanks.

Sorry my explanation assumed to much, I guess.

Read out of settings that are adjusted is the missing piece. In TV and AV modes we know we can set shutter speed or aperature and lock one of them in. We also know that by toggling on exposure with the joy stick, we can adjust the remaining non locked factors by manipulating the exposure plus or minus. The problem is, there is no read out as to what is being adjusted.

Again as example: First I select TV mode. When I do that, up in the display it says TV and then has current shutter speed bracketed on top and bottom with up and down arrows. I use the toggle to select the speed of shutter I want. Then I depress the toggle. the toggle screen appears. At this point the camera is automatically adjusting light input still. As I navigate to exposure and select it, the automatic action stops. Now, by manipulating joy stick, I can go plus or minus on exposure. I presume the camera is adjusting available things like: aperature, gain, and if there is anything on board, ND filters. The shutter speed remains untouched. With the adjustment of exposure completed, I can now toggle out of the exposure joystick menu, and shoot with camera completely locked in the current exposure.

There are similar approaches in the other modes in the Pmenu.

Phil Shima
April 16th, 2007, 06:47 PM
As the original OP, I still have questions - I come from a still camera background, using film (you remember film) cameras, w/ no auto settings. I'm wanting to know how close I can get to having full exposure control w/ the HV20:
- shutter speed
- aperture
- gain (aka asa/iso in filmspeak)
in other words, can I lock in a particular exposure (EV) without having the camera "adjust" the exposure for me?

p.s. - Thanks to all who have responded - you've been very helpful - I just need more info.

Jay Stebbins
April 16th, 2007, 07:30 PM
Phil,

I think many of us are in the same boat. Here is a link http://www.dvxuser.com/V6/showthread.php?t=92431 to a rather long thread trying to answer that very question. Pay attention to Barry Green's posts. Right about where he uses a cell phone to set the exposure baseline it gets good. Hopefully all the information between these two forums will get streamlined and consolidated. However, NAB is this week and most of the people who were making the most headway seem to be busy in Las Vegas.

Chris Barcellos
April 16th, 2007, 08:43 PM
Phil:

The post I made just above does just that. In either AV or TV, you select one or the, adjust your exposure further as you want it with the toggle joystick, and you are locked in. There is no other way to say it. You point out a window at that point, and it will zebra out, you point it into a dark closet, and it will be dark....

Peter J Alessandria
April 17th, 2007, 10:10 AM
As the original OP, I still have questions - I come from a still camera background, using film (you remember film) cameras, w/ no auto settings. I'm wanting to know how close I can get to having full exposure control w/ the HV20:
- shutter speed
- aperture
- gain (aka asa/iso in filmspeak)
in other words, can I lock in a particular exposure (EV) without having the camera "adjust" the exposure for me?


Phil - you can come pretty darn close. You can definitely lock your shutter and apeture. However, I'm still in the dark (pun intended :-))as to how you can also lock gain or ND's. [Note: for the following explanation the camera was set in Tv mode with a 1/48th shutter] The way the "EXP" setting seems to work is it depends on where you are when you set it (thus Barry's white cel phone screen trick). For instance, if you are in a dark closet and go from auto to "EXP" it looks like all you can control is the gain function since I assume the apeture is already wide open. A limited range of adjustment is available e.g., 0>>+9 in increments of 1 (starting in a normally lit room you'll get -11>>0>>+11 range of adjustment) It appears all or most of that adjustment is adding gain (due to noise visible in LCD screen). Likewise, if you start in auto with the camera pointed out a bright window switch over to manual EXP adjustment, you get a range of adjustment (sometimes a full +/-11, sometimes less apparently) but since you started with a bright exposure, even at +11 it will be too dark to expose a normally lit room. So in the second case it looks like you're controlling the ND filters and perhaps some apeture.

So the short answer is, yes you can definitely lock the overall exposure of the camera in either shutter (Tv mode) or apeture (Av). Then depending on where you started, you can manually adjust (through a sometimes limited range), some combination of gain, ND filters and either SS (if you're in Av mode) or apeture (if you're in Tv mode). Of course it would have been so much easier if Canon included separate gain and ND switches and an apeture/ss ring, but you'll need an A1 to get that.

Ken Hodson
April 17th, 2007, 01:32 PM
Thanks Chris/Peter. And for that link Jay, good read. I was an early adopter of HDV with the JVC HD10 and have had to jump through similar hoops in the past trying to figure out how that cam reacts to different settings. I had to use a variable ND filter(s) to control that cams exposure as you could not lock both shutter and exposure, but you could disable auto gain though.
What is the opinion of the Spotlight setting locking gain? Is this option available in a situation where the shutter is locked, and the exposure adjusted so as to be set?