Noise problem
 

I have been noticing noise in my footage with the A1 even when I change settings completely. Right now I am using Vivid Grab preset and 30f shutter is 1/60on the Manual setting and -3 gain. Also what level zebra should I use for outdoors. I am using 100 right now. Does anybody have any suggestions

Are you sure that the auto gain is turned off?

Jon

yes I made sure that the auto gain was turned off, but I still see a little noise and the picture doesnt look as crisp as it should be.

Sounds strange, do you have a screen grab? I use Zebra on 70 all the time, whether that is correct or not.
Was is moving shot or static and what were the lighting conditions like... what I am trying to get at is do you think that it is a gain issue or something else.

I was filming surfing so it was moving. The gain is at -3 so I dont think it is the gain. Im not so sure if it is noise but it seems that the resolution of my footage isnt as clear as it should be or as clear as all the peoples footage using A1s on vimeo and stuff.

For fast moving action I always shoot 50i (60i in NTSC world), I use 25f for more landscape, non fast moving stuff, all pans must be slow in frame mode too.

Also are you just viewing the footage on through the viewfinder or on a monitor.. in frame mode it always funny through the viewfinder but great on screen.

I upload the footage to my Mac. When I shot surfing in 30f though there were no skipping frames or any weird jitters.

Noise
 

From your description it would seem that you may be on auto focus or the gain is on auto. What shutter speed are you using? And are you certain you are not using auto focus. Incientally I keep my zebra on 85 all the time. This zebra setting is a personal thing, what a person gets used to.

Ditto what the others have said, but watch out that your aperture F-stop opening isn't too small, or you'll lose resolution and contrast to diffraction.

Adjust shutter speed, gain, and ND to get the lens working into the sweet spot of the range, F3.7 - F4.4 at the wide end of the zoom, and F4.0 - F4.8 at the long end of the zoom.

The XH-A1 exposure metering is a little too bright at times as well. Try reducing exposure slightly, to saturate the color and improve contrast.

I used both auto focus and manual focus but the viefinders and lcd are so small that I cant really tell when it is perfectly focused. So I ended up using auto focus. Do you think that if I used manual focus but pushed af at the begginning of a shot to focus then leave it on manual itwould be better then always using AF.

Phil I was shooting at 1/60 shutter speed at 30f.

John, since the viewfinder is so small, I take advantage of the "peaking" function when on location w/ no monitor. That helps me see focused lines better (it makes the viewfinder overly sharp, but not the actual recorded picture). I seldom switch it over to AF. Instant auto-focus spazes out frequently, and it's not perfect anyway.

And I agree with Jonathan... shooting 60i helps with faster subjects. If you like the stuttery-ness (not sure what word to use there) of 30F, then try increasing the shutter speed (if you can afford losing some light) to avoid too much motion blur. Try 1/120 or 1/300.

It's hard to offer advice when we can't see the problem, post a frame grab and we can have a look.

Noise
 

I just won't use auto focus unless it's a stationary shot and even then I don't like to use it. I suppose it's ok if you are shooting something quick without having the time to manually focus. I have had too many "vertigo" footages because of auto focus so I just don't use it. As far as your shutter speed is concerned I would shoot at 1/300 or so. You will get blurring at slower shutter speeds in shots involving movement such as surfing. I shoot mostly outdoor video and I try to keep exposure f stops at 5.6 or higher. In the outdoors f 11 is great as most of the time you are looking for great depth of field. Back to manual focus, or manual everything, if I were you I would force myself to shoot in manual mode. It won't take long to become one with your camera. You will become a better videographer in time if you do. Once you get used to shooting in manual it will become second nature to you and the chances of shooting lousy video will be reduced dramatically. Then if you have to you can occasionally go to auto something but you won't feel good about it.

I will try and put up the clips I have gotten so far onto vimeo.. Does anybody know what the best exposure to set to get the best quality. Ive been hearing around 4 to 5.8 is good am I correct?

Thats what I aim for...

heres some clips that I have gotten on my Xh A1 so far...if you guys have any advice on how to get better pictures let me know please. I know the filming is bad but I have it wired now so that wont be a factor anymore.

http://vimeo.com/1120774

Only reduce your shutter speed if you want jittery motion. The faster the shutter, the more jittery the motion effect will be. For smooth motion, shoot 60i at 1/60 or 50i at 1/50. This is moving-, not still-photography.

Although this is normal practice with 35mm still cameras, it's not good advice when using such small detectors/short focal lengths as in a 1/3"-chip video camera. You will find that you start to get colour fringes appearing on high-contrast edges at appertures smaller than about f5.6. Now, it is possible to make lenses this short that don't do this, but they are very expensive and very heavy, and zooms are even harder than fixed-length lenses. The Canon lens is better than most, but not perfect. This is why Tom Roper was talking about the lens' "sweet spot". Except at the long end of the zoom or when focusing on very near objects, lack of depth-of-field is not a problem with such short lenses/small detectors. (Indeed - some videographers go to great lengths to try to reduce the depth-of-field of these cameras! Just look at all the discussions of Red Rock and Letus lens adaptors, for example)

There will always be occassions when these rules-of-thumb don't apply, but most of the time:
- match the shutter speed to the frame rate,
- use higher frame rates for smoother motion,
- keep the apperture between about f3.2 and f5.6,
- turn off auto-gain,
- use the ND filters (and perhaps set gain to -3db?) to help keep things where you want them.

As the light decreases, this is what I do:
- remove ND filters;
- open the apperture;
- use a slower frame rate and/or shutter speed (I sometimes use 1/25 with 50i, which works well enough for slow-moving subjects);
- change knee and/or black settings (for more dynamic range, more detail in shadows, etc) ;
- add gain: with a little help from the NR2 and/or coring settings, +6dB is not too bad;
- in extremis, switch on AGC, on the basis that any shot is better than none!

HTH

John,
What was wrong with that clip? I didn't see any problem at all. This why I'm happy about not being an "expert" I can overlook the little things and just enjoy life. BTW that was some SICK surfing footage. WOw. I'm from a place where that type of thing is just on TV much less happening right in front of me, much less getting to film it. Great stuff. And apparrently you have skaters there that can land tricks. None of the kids here can land tricks... oh well.
Bill

Noise
 

I stand by my suggestions! Experience your camera and don't get caught up in all the technical lingo that confuses the real world for you.

Noise
 

As a follow up this is an article by Marshal Rosenthal for Videomaker several years ago. It explains in more detail the relationship of shutter speed, f stop and frame rate.

Speed Tips
Marshal Rosenthal
October 2004
Most of us don't think twice about the shutter speed that our video camera is using. True: it can be set to manual, but since the camera can automatically take care of it, why should we bother? The answer is that you gain control. And you get control over more than just exposure. This means that you can shoot video that isn't blurred (or is), that the scenes don't look too dark, that, in a nutshell, what you've shot appears the way you want it to look.

The Way Video Cameras Work
Now let's take all this and apply it to a video camera which, while it has a shutter, is dealing not with a single image, but with dozens upon dozens of single images strung together. And the speed at which these frames are moving must be both constant and fast enough to create correct looking, full-motion video when played back.
So the video camera shutter is firing very fast as the recording media (video tape, DVD, memory chip) is being bombarded by the light which has been converted into data by a light sensing chip. Still, as the light is first going through a lens, physical properties such as the amount of light in the scene and how fast the shutter is going off apply here just as they do to a still camera. So the faster the video camera shutter fires, the more light is needed to keep the scene from becoming too dark. Being aware of this means knowing when you feel it makes sense to manually change the shutter speed of the camera, speeding it up or slowing it down, depending upon what you're shooting.

Focus, Depth of Field and The Shutter
We know that when we watch a movie or TV we're actually seeing a successive number of frames flipping by one after another and that it's our eye working with the brain that stitches them together to create motion. While a still image that is blurred will be obvious, in a movie, individually blurred frames are less noticeable. In fact, a slight blurring might be a very desirable effect. Video that is too crisp and sharp can have a very artificial feel to it.

Understanding the Terms
To better understand how this all interacts, let's look at what the terms mean. Focus, at its most basic, is when an object is sharp and clear. Whether focus is for a single object, say a cow in a meadow, or for an entire scene (the cow, the meadow and the mountains in the distance) is the result of the depth of field. This is the range where focus is sharp in front and behind an object. A narrow (shallow) depth of field limits what is in sharp focus, while a wide (deep) depth of field keeps everything in focus, from one foot to infinity. For example, say you focus on an orange sitting on a table. Depending upon the depth of field, the orange could be in focus, while the front of the place mat is not and the chair at the end of the table behind the orange is also out of focus. Sufficient depth of field insures that more than just the object in your sights is in focus. A narrower depth of field is great for artistic purposes or to emphasize a subject.
The camera lens F-stop primarily determines the depth of field. The F-stop is a ratio measure of the size of the aperture (iris). This is all about the amount of light that a lens can gather. When shooting a scene, an F-stop of 1.4 or 2.0, for example, will be able to work in lower light situations, such as when it's dusk or inside a room with little illumination. Depth of field decreases as the F-stop number shrinks. Conversely, if there's more light to work with, you can go to a higher F-stop such as 5.6, 16 or 22. The higher the F-stop, the more depth of field there is and so the greater the range of focus. Since the F-stop and the shutter work together to control the exposure, you can choose a lower F-stop and higher shutter or a lower shutter and higher F-stop to maintain your exposure.

Preset Shutter Speed Settings
Rather than being forced to either leave the camera totally on automatic or make all the choices for yourself, many video cameras have preset scene settings, such as for sports or action shooting, landscapes, night scenes and portraiture. Each of these settings alters the shutter speed to what is more optimal for the given situation. For example, say you're shooting a football game, which means fast moving people. Freezing the action (on a frame-by-frame basis) requires a very fast shutter speed, say 1/1,000th of a second or greater, assuming that we otherwise have plenty of light. By the same token, using a setting designed for shooting a still life subject means a lower shutter speed, since movement is assumed to be more minimal. In all cases, the frame rate (30 fps) remains constant, since that is defined by the video format.

It's Your Choice
It's fine to let the camera's automation do the work for you, but that shouldn't make you lazy. Understanding how the shutter speed works is the first step towards deciding when it's the right time to control the camera by yourself, so that you can get the results you want.

Marshal M. Rosenthal is a technology/entertainment writer whose experience in the industry spans 20+ years.

SIDEBAR:
Slow Shutter and Effects
When you drop the shutter speed to 1/30 or below, you are losing every other line of resolution in your camcorder (unless you are shooting progressive on a special camera). At 1/15, you'll find that the video is noticeably stuttering. At 1/4 (four frames a second), the video will look rather poor and will show a lot of blurred action. You will, however, be able to shoot in very dark situations and, in our opinion, if that is the difference between getting the shot and not, 4 fps is better than zero.

SIDEBAR:
1/60 Default
Technically, the minimum shutter speed you should consider for video is 1/60 second. In fact, you should consider this the default shutter speed, since this is a rate that matches television in the US. Any higher shutter speeds (as discussed in this article) are for effect only.

Thanks for all your guys help. I really appreciate it and will definitely use it in my filming. We are supposed to get a swell in the next couple days and I will try and film with my new settings that I got with your help, and I will try to post it on vimeo. Thanks again

Just looked at the Vimeo link John, its hard to see real issues due to compression etc.

I liked the footage... was that shot in 30F.

As per previous posts, I would play around with the camera, with surfing you can go nuts to get different effects / feels. No rules...

The only this I wouldn't do is shoot different frame rates on the same tape. I'm sure people do but it makes capture a little more interesting.

Phil, the XH-A1 does not give good results at f11. Diffraction may be technical lingo but that doesn't mean it's not real.

Richard

Hey John,

I checked out your footage on Vimeo. Man, those are some good riders - that'd be heaps fun to shoot.

Looking at this footage, most of the noise I'm seeing seems to be from the compression rather than the camera. You'll generally get some compression artifacts with fast moving subjects like the ones you're filming - especially waves, leaves etc ... The skateboarding stuff didn't seem to have the same issues as the surfing stuff.

With my old XL2 I used to shoot on 0+- gain all the time but I've found the A1 to be a bit noisier at 0 so I use -3db almost all the time.

Most of the time I shoot in TV mode and let the camera take care the exposure - unless the light is changing quite dramatically. I love the Exposure Lock button as well - it's good for 'tricking' the camera - i.e. point the camera at an area with the correct exposure you're after, hit the exposure lock and away you go. It's often a combination of a lot of things - i.e. correct exposure, ND filters, sometimes Manual mode is best etc ...

The biggest thing I've learned is that there's no magic recipe as every shooting environment is going to have different light. Experimenting with your camera and shooting lots of footage in different lighting conditions is the best way to figure out how your camera handles different situations and what you need to do to get the best out of it.

That's the cool thing I've found with cameras like the A1 - they are so customisable that there's heaps of different ways to use them. The way I use the camera may be totally different to how another shooter would do things. You just have to spend the time getting to know your camera to find what works for you in producing good looking footage.

Here's some of my stuff on Vimeo that I've shot so far with my A1 - if you want to check it out: http://vimeo.com/ebenezer/videos

Keep at it - the A1 is a sweet camera for sure - especially once you push through the learning curve.

Cheers,

Matthew.

I agree wholeheartedly. When I first read Phil's recommendation regarding f11 a couple of days ago, I thought it was a typo :) I'd like to see what that footage at f11 looks like. I'm sure Phil means well but that just isn't sound advice in my opinion. I can't imagine anything with detail holding detail due to diffraction.

I target f5.6 & a tad more open for my sweet spot.

Noise
 

No typo here. I do shoot quite a bit of video at f11. It looks good and always will if you have enough light to use the smaller lens openings. Otherwise, Canon would not supply such a lens. Nope, I do stand by my statements and suggest John Campbell try a faster shutter speed at f11 (if there is enough light and outdoors in the sun there will be plenty of light). If you want a large depth of field, a desire for most outdoor videographers, you'll have to use larger numbers for iris openings. As Marshall stated, "Depth of field decreases as the F-stop number shrinks. Conversely, if there's more light to work with, you can go to a higher F-stop such as 5.6, 16 or 22. The higher the F-stop, the more depth of field there is and so the greater the range of focus."

The narrowest F-stop that the XH-A1 is capable of is F/9.5. Diffraction isn't the only reason to avoid f/5.6 through f/9.5: on my camera it exhibits the dust on the sensors or prism block. (Dust on the lens shows too, but that can be cleaned.)

You're cheating this forum by not posting full resolution screen grabs.
What should have been a highly educative thread is doomed to be purely speculative.

yup
 

All of these Digital enhanced video cameras , produce grain when you use even the slightest Gain db...

Hey guys, we had a little south swell yesterday so me and my friends went and surfed and tried out the new settings on the xh a1. It looks a lot better then my other footage I got. Heres a little movie I put together of our 2 sessions. If you have any more advice I would love to hear it. Thanks

http://vimeo.com/1139050

I looked at your two video samples. It could be that the first one is grainy because it is underexposed.

There is a drawback to the A1 long zoom: aperture is not constant. In the telephoto setting, the aperture is smaller than in the wide angle setting. If you use manual mode and set the aperture wide open in wide angle, and then zoom in, the telephoto setting will be underexposed.

Furthermore, filming at see is tricky: you'll have plenty of light, but the see is relatively dark, so the water may be underexposed if reflections of the sun or bright objects are in the picture.

Hey John,

The footage in your new clip is definitely better quality than your first one.

My only thoughts would be that the foam/froth of the breaking waves is quite blown out - but you've done really well overall - a big improvement over your first clip.

What settings did you change?

Hi Matt, I also did realize that the whitewash looked a little white also. I pretty much changed all my settings. Last time I was shooting in Auto setting and this time I used Manual. I used 3db custom preset, shutter speed 1/60, auto focus, and image stabilization (which might have messed up a few shots), and I kept exposure at 5.6 because I heard you get best resolution at that setting. Gain was at -3 and I used outside white balance setting. 60i. I think thats pretty much it. Do you think if I shot in 30f it would look more like something that you see in a professional dvd?

Hi Phil. This is not good advice to give to anyone using a videocam that has a small sensor. Yes the depth of field is greater at small apertures but at the same time the image loses sharpness due to diffraction. You end up with a picture where nothing is sharp at all. Maybe Marshall had a specific class of camera in mind when he wrote that?

You say it looks good "and always will" but my own experience does not support that at all. A couple of comparison shots of some detailed stuff like plants and trees at wide and narrow apertures will show quite different sharpness levels.

Richard

I dug up this old article about diffraction.

http://www.dvinfo.net/canon/articles/article19.php

Although it talks about f8 and f16 here, you need to bear in mind that the camera mentioned has a lower resolution sensor compared with the XH-A1. When you talk about HDV resolution sensors, the diffraction effects start at an even larger aperture.

Richard

I'm afraid that Phil's advice is not good, at least as far as video cameras like the XH-A1 are concerned. The essential point to keep in mind is that the CCDs, at only 1/3", are very small, compared with film and even digital-SLR photography. This means that the focal-length of the lens is very short (something like 4.5mm at the wide end, IIRC, which gives a similar angle of view to the 35mm lens on a 35mm camera) and therefore, diffraction effects from very small appertures (less than 1mm at f8??) start to be a significant problem. I don't expect anyone to take my word for it. Adam Wilt's recent review of the Sony Z7 includes a short discussion and a perfect illustration of the effect (see this thread).

Likewise, except at the long end of the zoom, or when focusing on close objects, depth-of-field is not a problem with such small detectors. Of course, HD is less forgiving of poor focus that SD, but with a little care and knowing when you can and cannot trust the auto-focus, you shouldn't have a problem getting sharp images at f4 - f5.6 with these cameras.

As for using fast shutter speeds - do the experiment and decide for yourself whether the stuttery motion effect is what you want. Personally, I'd add ND filters and keep the smooth motion, rather than speed-up the shutter.

At least the XH-A1 gives us the facilities to adjust these parameters ourselves to create the effects we want. The difficult part is understanding what happened when we get effects we didn't intend!

Noise
 

Ooohhhhhhhhhhhhh. Well I guess I should stand corrected. However, there is more to this subject than meets the eye in this forum. I will attempt to respond to the diffraction issue later (the technical details are a struggle for me) however I stand by my statement abut shoting at f11. The Canon literature states "You can select from 21 aperture settings (with HD 20? L IS lens). The setting can be adjusted in 1/4 steps. However, only the following numbers are displayed on the screen: F1.6, F2.0, F2.8, F4.0, F5.6, F8.0, F9.5, CLOSE." Now, though you may see 9.5 in the viewfinder what that means to me is really an f stop of f11, the maximum of this lens. The 1/4 step situation is a bit confusing but I believe that when you see 9.5 in the viewfinder, depending on the light intensity, you are actually at f11. Then chromatic abberation and/or diffraction can occur depending on a number of other factors. It is most commonly seen on the edges of buildings or stand out subjects and may represent itself in overall softness of the image. I don't see that in my outdoor video. And there is a reason for that also. But one just has to shoot and observe what the video looks like to see if you are experiencing diffraction. The laws of physics as they relate to diffraction seem clear and locked in stone except for the occasional variances permited by lens design changes, Flourite lens elements for example.