I have had my xha1 for a while now and have typically shot 60i. I know there are lots of threads that discuss this, but I was wondering what other xha1 users are using.

Wouldn't you just use 1/60 to get a 180 degree shutter? That should leave the sensor exposed for half the duration of the frame, correct?

The last few shoots I have shot with a shutter speed of 30. It was low light situations and the final result seemed fine. However, it appears that lots of people recommend using a shutter of 60 when shooting 30p. I was wondering if XHA1 users have obtained better results with a shutter of 30 or 60 when shooting 30P.

I gotcha. That makes sense. I pretty much would not deviate from the 1/60 shutter speed just for the motion blur. But in low light situations I guess actually exposing the sensor may take precedence over correct motion blur. Because what good is the motion blur if you can't see it? :)

Since a lot of us still use the old names, I'm assuming that your reference to 60i means 30i and not a slow-motion format. A couple of years ago, the poobahs who set nomenclature standards decreed that the "60i is to be referred to as 30i because we shall refer to frame rates, not to field rates For example, "1080/30i" means shooting 1080 lines at 30 interlaced frames per second which is the same as 60 interlaced fields. 1080/30p is still "30p" for obvious reasons. Same with 1080/60p. Under the new scheme, 60i would be 60 interlaced frames or 120 fields per second. That would be something you would use for slow-mo but not everyday shooting.

So, assuming that we are talking about what you might do different under 30p than 30i, I haven't found much need to do things differently.

Basically, I use 30i for anything with high-motion content. For low light situations at weddings, I go down to 1/30th with 30p. I've also gone with 1/24th when shooting 24p. Some folks would be concerned with motion blur, but dimly lit weddings typically do not have a lot of very rapid motion. I've tried a 1/15th shutter setting, but there was too much motion blur for my tastes. I've never tried 1/8th or 1/4 with any video camera.

If I'm shooting something where I need a high-speed shutter, it is because it is a high-motion activity and I prefer 30i for those kinds of things. (I like 60p but the XHA1 does not offer it.)

In theory (so far as I understand it), there is something to be said for using shutter speeds which are multiples of your frame rate. If you want to try shooting high motion with a 30p frame rate, setting XHA1 to M mode will let you select even multiples of 30 for your shutter speed, say 1/600th. (See p. 57 of the manual). Conversely, if you wanted a film-like motion blur, you could try a lower shutter speed. Beyond this, I recall reading about shutter angles for film cameras, but have not had any jobs where I have needed to understand and apply those concepts. Maybe somebody with more knowledge and a film background (Justin??) could contribute on how to use shutter angles with the XH?

When you set the XH to Tv mode, you get a more limited selection of shutter speeds, most of which are not multiples of 30.

For the most part, I haven't had trouble with using aperture priority and letting the camera set the shutter speed. I'm mostly shooting for DVD for local event customers rather than large scale projection which could make a difference in whether I would see problems or artifacts.

The one thing I've found requires caution with shutter speeds is shooting under older flourescent and mercury vapor light fixtures. The manual warns that can cause flicker We have some near antique fixtures in our local venues in this area and boy do they ever flicker. The XH manual says to use 1/100th as shutter speed (Manual p. 55). That took care of the problem for me and I have not been tempted to experiment since then.

Jay thanks for your input, but your post just confused the heck out of me.I'm simply trying to find out what the best shutter speed under normal circumstances when shooting with the xha1 while recording 30p. By normal I mean controlled lighting situations and not shooting a fast motion sporting event.

Film cameras have a disc in them that rotates in front of the film. This disc has an opening in it which allows light to expose the film. For film cameras there has to an amount of time where the film is not exposed to light during the duration of the frame so that the next piece of film can be pulled down. This opening in the disc that allows light to expose the film is measured in degrees. This opening is usually 180 degrees. Meaning for half the frame the film is exposed to light, and the other half of the frame the film is in darkness. During this period of darkness the next piece of film is pulled down. Over time people have grown accustomed to the motion blur produced by the 180 degree shutter angle of film and generally find it to be very pleasing.

It's simply not possible for a film camera to have a 360 degree shutter because the next piece of film could not be pulled down. Only in video cameras and digital film cameras is it possible to expose the image during the entire duration of the frame. This produces a much smearier motion blur which quite a lot of people find to be quite ugly.

My knowledge of video pales in comparison to the guys on this forum. So I'm guessing they do all kinds of tricks to make stuff work in particular situations. But the longer you expose the image the more smearier your motion blur. If that doesn't bug you then I guess it's all good, but it's going to look less like film. If you want a beautiful film style motion blur and you are shooting at 30 fps then you need a 1/60 shutter and if you shoot at 24 fps then you need a 1/48 shutter.

-Justin

Kevin:
Sorry I confused you but my experience is there is no such thing as a single "best" setting. The question , as always, is "best for whom to shoot what and where?"

So, your response helps narrow things down. When you say "controlled lighting" and "not shooting a fast moving event," that sounds to me like it might be studio conditions or, maybe, say, a panel discussion or a meeting room or a church service where you do not need to worry about things like depth of field in your focus.

For that, I would start with 1/60th as the setting most likely to give the best results with 30p under those conditions, and then vary the iris as needed.

Which leads me to the reason I mentioned that there are differences between setting the XH to the Tv (shutter priority) setting on the control dial as opposed to the M (fully manual) setting. With the Tv setting, you are only setting shutter speed and letting the camera handle all of the other settings needed to control exposure. The issue for Tv mode is that you get far fewer choices than you do with M mode, and not all of those choices seem appropriate for shooting 30p indoors. Under Tv mode, the shutter speed choices (the one appropriate for indoors under controlled lighting) are limited to 1/60th, 1/100th, and 1/250th. But, if you go to fully manual mode, you get some additional choices, such as 1/90th and 1/120th, that may be more appropriate for your specific lighting and setting.

My knowledge of video pales in comparison to the guys on this forum. So I'm guessing they do all kinds of tricks to make stuff work in particular situations. But the longer you expose the image the more smearier your motion blur. If that doesn't bug you then I guess it's all good, but it's going to look less like film. If you want a beautiful film style motion blur and you are shooting at 30 fps then you need a 1/60 shutter and if you shoot at 24 fps then you need a 1/48 shutter.

-Justin


Boy howdy, doesn't this forum teach a lot!

I know about as much as you described about shutter angle for film cameras. I just can't quite figure out how to translate that to what I do in video. From film classes (a ling time ago) I remember a lot more about aperture settings affecting depth of field, and that, at least, I still understand.

I'm not so sure you get lot of motion blur at 30p with a 1/60th shutter if you've got a relatively static scene (say, people talking from a table). If you have somebody walking back and forth, I think it will be different. 1/90th or 1/120th might be a better choice for 30p indoors in those conditions. A lot of the time /160th will be as fine for 30p as for 30i.

Jay: You are correct, it is a studio setting that I will be filming in. I am doing a green screen shoot under very controlled condidtions. When the camera is set to the "A" mode, it appears that it uses a default shutter of 30 when shooting 30p, which seems to be contrary to what i've been reading. As far as the green screen shoot is concerned, the subject will remain in one postion the whole time and wont move from the mark.

I suggest you set the XH to "M" mode, set your shutter speed to 1/60th, set your zebra stripes to 100%, and dial the iris to adjust the exposure. Switch to manual focus to avoid any possibility of variation or any change in lighting causing the autofocus to hunt.

If I'm shooting something where I need a high-speed shutter, it is because it is a high-motion activity and I prefer 30i for those kinds of things. (I like 60p but the XHA1 does not offer it.)


Jay, the A1 doesn't offer 30i either! :D So how are you accomplishing that?

I just can't quite figure out how to translate that to what I do in video.

There's not terribly much to do honestly. for video to look more like film then shoot 24 fps with a 1/48 shutter speed. People debate the heck out of this idea, but I'm pretty much on board with 24 fps and a 1/48 shutter speed. I guess the game changes when you're not concerned about the film look. It seems like people shooting weddings and stuff like that are more worried about other concerns. But if you're shooting in controlled conditions with directed lighting I can't imagine why anyone would want to shoot at any other settings. Unless of course you have to cut that footage in with other footage shot in non-controlled conditions in a remote location. Then maybe you'd want to match settings between the two.

...If you want a beautiful film style motion blur and you are shooting at 30 fps then you need a 1/60 shutter and if you shoot at 24 fps then you need a 1/48 shutter. Justin

I don't agree, because no CCD camcorder can make a beautiful film style motion blur. It is impossible at HD resolution (1920x1080) with a CCD/CMOS technology.

Shutter speed is CCD/CMOS parameter, it is time for exposure the light-sensitive sensor elements. If you want max. amount of light, you can set 1/50 shutter speed at 1080/50i (right 25i) or 1/25 shutter speed at 1080/25p (*europe version).

CCD of the XH-A1 is native interlaced processed, 1/50 sh.speed is right for 1080/50i (I do not know the internal structure of CCD, it is possible, that CCD scan at 50p but one half of the information is immediately destroyed...).

The rest about "a beautiful film style motion blur" is illusion and fantasy .-) .

---

On the other hand is right, that with fast moving you can use a shorter time for a sharper picture (at 1080/25i or 1080/25p) , but it can cause a strobe effect (it depends on speed in scene and shutter time).

Jay, the A1 doesn't offer 30i either! :D So how are you accomplishing that?

Sure it offers 30i. As explained at the outset, the international standard terminology has been revised. What we used to call 60i is now officially described by international standards as 30i -- that is 30 frames (okay, 29.97 frames) per second interlaced to produce alternating fields which is to say, 60 fields. A lot of folks still say "60i" because it is in the camera manual and because it makes intuitive sense -- 60i sounds like describing 60 interlaced fields. The standards bodies thought that frames were more important as a standard. Hence, 30i and old 60i are the same thing. 30p and 60p were not and are not the same.

I don't agree, because no CCD camcorder can make a beautiful film style motion blur. It is impossible at HD resolution (1920x1080) with a CCD/CMOS technology.


OK...well, as close as you can get with a CCD or CMOS sensor on a video camera. Apologies if I got carried away with comparing this footage to film. Obviously this video camera is not film. The files I get off this camera are 8 bits and compressed. It doesn't respond to light the same way. I get that. But it's closer than exposing the image for the entire duration of the frame which will produce a more smeary effect. I dislike the smeary motion blur, but that's just me. I'd rather have my image look as close to film as I can get it. Following the 180 degree shutter look is only part of the way there, but I'll take it.

There's not terribly much to do honestly. for video to look more like film then shoot 24 fps with a 1/48 shutter speed. People debate the heck out of this idea, but I'm pretty much on board with 24 fps and a 1/48 shutter speed. I guess the game changes when you're not concerned about the film look. It seems like people shooting weddings and stuff like that are more worried about other concerns. But if you're shooting in controlled conditions with directed lighting I can't imagine why anyone would want to shoot at any other settings. Unless of course you have to cut that footage in with other footage shot in non-controlled conditions in a remote location. Then maybe you'd want to match settings between the two.

I guess I was unclear about this, too.

When I mentioned shutter angle, I was not talking about trying to get a film look (for which there is a lot more than just slow shutter speeds.) Personally, I could care less about having a film look for the things that I get paid to do. Mind, I'm not opposed to people trying for film looks. I just do not care about it myself.

We got sidetracked because it was not immediately clear how specific Kevin's question was. Now that Kevin clarified his specific aim, I rather suspect that Kevin is shooting the green-screen studio stuff for web distribution. That is a format where shooting in 30p can make sense.

I only commented about shutter angle when Justin mentioned it because from what little I understand of it, shutter angle is a way of describing a relationship of shutter speed and frame rate. If you understand it, supposedly it helps pick shutter speeds that avoid artifacts such as the strobing that Pavel mentioned as resulting from using some faster shutter speeds when shooting 30p.

Turns out that we do not need to go deeper into this because Kevin doesn't need higher shutter speed for what he is doing.

Sure it offers 30i. As explained at the outset, the international standard terminology has been revised. What we used to call 60i is now officially described by international standards as 30i -- that is 30 frames (okay, 29.97 frames) per second interlaced to produce alternating fields which is to say, 60 fields. A lot of folks still say "60i" because it is in the camera manual and because it makes intuitive sense -- 60i sounds like describing 60 interlaced fields. The standards bodies thought that frames were more important as a standard. Hence, 30i and old 60i are the same thing. 30p and 60p were not and are not the same.

I understand where you're coming from and that whole 60i naming convention biz never made sense to me either. It just creates confusion to some. I've heard people who were relatively new say they were shooting in 60fps when in fact it was 60i. But... 60i IS 60 interlaced FIELDS p/s (30 or 29.97 frames)... as 50i IS 50 interlaced FIELDS p/s (25 frames etc) for PAL. In other words fields are separated by 1/60th or 1/50th of a second so it's been commonly called 60i / 50i blah blah :) Frames aren't interlaced and can't be... fields are. Frames have no fields. It was just because you made it sound as if there was a 30i option that you choose to shoot in with the XHA1, which there isn't. 60i, 30f & 24f are the only options (NTSC anyway). Yes... the 30i you see at times now with other cameras is the same as 60i in cameras from several years ago, but calling it something different from what it is with whatever particular camera just for the sake of it will... again... create confusion among some.

I'd rather have my image look as close to film as I can get it. Following the 180 degree shutter look is only part of the way there, but I'll take it.

Yes, it is right. Everybody can "make look" by using shutter speed, DOF, etc. It's his choice.
There is only one way how to decide - what do you like on TV screen it is ok.

This is what I mean. It depends on the speed of movement on scene, it depends on what look do you like, it depends on the amount of the light - it is a correct answer. If you set a shutter speed to 1/25 (at 1080/25p, right 1080/25F for XH-A1), you minimize a strobe effect - shutter is open all the time, any phase of the movement does not lack (...depends on speed), it maximize amount of light for CCD's.

I can only recommend to compare the look of film vs HD video on the same screen with the same dimension.

This is going to date me, but I remember many film cameras used a smaller angle than 180 degrees, e.g. it was 135 degree on a Bolex H16, the DVX of its day, and this was variable to half - I think the idea was to provide close to 1/60th and 1/120th sec (at 24fps). - can't remember precisely, someone else do the maths. So you don't lose the "film look" by shooting 1/120 sec. As for 30/60i,p, be prepared for fruitless conversations with people insisting their next camera has at least to be 60p ('cause the salesman explained this is 4 times as good as 30i').

Ah, yes, the old Bolex. That dates me, too. As I recall, we had a Bolex H16-M-5 for the film class, and it was a year or two after they first came out. (That's a long time ago for you young folk.) I can remember the model number and have a vivid memory of somebody giving a very detailed explanation of the maths. For the life of me, I cannot remember any details from that lecture. Because I cannot remember the maths, I've just used the rule of thumb about shutter speeds being multiples of frame rates. Kevin's studio shot should go fine with 1/60th as the shutter speed. Using 1/120th would require a somewhat larger aperture which could result in a shallower depth of field, but also would work fine. I think 1/60th easiest to work with indoors for a project like Kevin's.

I understand where you're coming from and that whole 60i naming convention biz never made sense to me either. It just creates confusion to some. I've heard people who were relatively new say they were shooting in 60fps when in fact it was 60i. But... 60i IS 60 interlaced FIELDS p/s (30 or 29.97 frames)... as 50i IS 50 interlaced FIELDS p/s (25 frames etc) for PAL. In other words fields are separated by 1/60th or 1/50th of a second so it's been commonly called 60i / 50i blah blah :) Frames aren't interlaced and can't be... fields are. Frames have no fields. It was just because you made it sound as if there was a 30i option that you choose to shoot in with the XHA1, which there isn't. 60i, 30f & 24f are the only options (NTSC anyway). Yes... the 30i you see at times now with other cameras is the same as 60i in cameras from several years ago, but calling it something different from what it is with whatever particular camera just for the sake of it will... again... create confusion among some.

Bill:

Confusion is indeed a problem. That's why I explained the nomenclature thing to Kevin in my first post in this thread, and why I tried to remember to say "60i/30i" thereafter. Sorry if you missed that.

Ok, i've done some experimenting over the last few days. It seems that under controlled studio lighting, the camera tends to gravitate towared a shutter of 30 when in the "A" mode. there does not seem to be that much of a difference between a shutter of 30 and sixty with the exception of having to let more light in when using a shutter of 60. Since its a stagnant shot, it appears that a shutter of 30 will work just fine. I will continue to do testing under different lighting scenarios and see what happens.

a quick comment regarding 180 degree shutter speeds, ESPECIALLY in films. just because the audiences are USED to it does not mean they find it PLEASING.

same with the new TSA regulations; i am sure people will get USED to getting blasted by x-rays and peeped at or fondled, but never find it PLEASING.

i personally HATE 24P, and i dislike the motion blur at 1/48 shutter speed; i have always noticed the 'flicker' in a movie theatre and it always irritated me. even if i shoot 24P, im usually at 1/60. a person walking or turning their head should not look blurry in a movie.

a quick comment regarding 180 degree shutter speeds, ESPECIALLY in films. just because the audiences are USED to it does not mean they find it PLEASING.

same with the new TSA regulations; i am sure people will get USED to getting blasted by x-rays and peeped at or fondled, but never find it PLEASING.

i personally HATE 24P, and i dislike the motion blur at 1/48 shutter speed; i have always noticed the 'flicker' in a movie theatre and it always irritated me. even if i shoot 24P, im usually at 1/60. a person walking or turning their head should not look blurry in a movie.




With 30P or 60i, i usually shoot at 1/60 for wedding/events, and around 1/250 or higher for action shots (motorsports etc)

Update: Thanks to all that gave input. I used a shutter speed of 60 and it worked out great.