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-   -   Possible problems when setting shutter speed to 30 (https://www.dvinfo.net/forum/sony-hvr-z7-hvr-s270/486757-possible-problems-when-setting-shutter-speed-30-a.html)

Allen Bartnick October 28th, 2010 03:45 PM

Possible problems when setting shutter speed to 30
I am trying to cut down the video noise, I have read & tried setting the shutter speed to 30. It made everything brighter so I wouldn't need as much gain but is there any problems I should be aware of. I am video taping weddings and creating mostly DVDs & a few Blu-rays. I know there is a chance for bluring but I didn't see any in my tests.

Thanks in advance for advice & input.


Dan Crowell October 28th, 2010 07:22 PM

Allen, sounds like you're on the right track....I shoot primarily in 30p and in low light I set the shutter to match the frame rate or on higher end cameras just turn the shutter off which achieves the same thing. Do some tests to make sure it's what you're looking for. If there's very little or no motion you can continue to turn the shutter speed down. Sony's CMOS sensor will literally see in the dark.

Allen Bartnick October 28th, 2010 07:49 PM

Thanks Dan, it's good to hear other people are doing it.

Don Bloom October 28th, 2010 08:12 PM

While I'm not shooting the Z7 or S270 I have shot weddings at a shutter speed of 1/30 in very dimly lit venues. For ceremony's it shouldn't be any kind of problem since there is very little movement. Receptions could be a problem during dancing but honestly even shooting 4:3 SD I never really had a problem with motion blur. It just kind of looked like it belonged and if lighting was just right it actually looked pretty cool.
You should be just fine shooting 1/30th especially if you're shooting 30P.

Allen Bartnick October 29th, 2010 05:07 AM

Don, I have been shooting in 60i, should that matter?

Don Bloom October 29th, 2010 09:06 AM

Well since I'm still in the dark age shooting PD170s all I can say is I've never had a problem shooting 1/30th of a second. I would shoot 30p if I could but of course I can't and I would say the motion blur would probably be somewhat less noticable but again when I have shot at 1/30th with the PDs I haven't really had any problem doing so. You can notice some blur but none of the clients I've delivered the footage to have ever said anything and to my eye it's really not a problem. Please keep in mind that YMMV ;-)

Jay West October 29th, 2010 10:32 AM


For stopping down while using HD cams in dimly lit receptions, I've tried to follow these simple practices.

(1) try to "track" (move side to side) rather than panning the camera;

(2) set the zoom to full wide and leave it there (this gives you maximum aperture; zooming in limits how wide the aperature can go; if you need a closer shot, step closer)

(3) Before starting, set and use manual focus (which keeps the auto focus from "hunting" when the light gets particularly dim.)

(4) Use a second, locked down cam to provide a cut-away shot for when you need to move or refocus the main cam. For several years, my locked-down cam was a Canon HV20 which was set to HDV/pf24 with the shutter speed at 1/24th. With my new Sony CX550v, I've gotten good results by simply turning on the "low light" function. It matches well with my NX5u.

When you asked if it mattered that you had been shooting 60i, were you asking if you could mix the 30p footage on a timeline or on a DVD? It has not been a problem for me with PPro and Encore CS3 through CS5.

Allen Bartnick October 29th, 2010 02:30 PM

Thank you everyone for the responses. I have been shooting in 60i, if I set the shutter speed to 30 do I need to shoot in 30p or can I still shoot in 60i. Thanks

Jay West October 29th, 2010 09:43 PM

Okay, got what you were asking.

Sure you can shoot 60i with the shutter at 1/30th. That's what Don was talking about doing with his PD170s and which is what I do with my cams. Basically, the steps for me are: try 1080i at 1/60th; if the scene is too dim for that, try 1080i at 1/30th; if the scene is still too dim, try 1080/30p at 1/30th; if that doesn't work, try 24p at 1/24th. (I shot one wedding last year where the planner/orchestrator kept turning the lights dimmer and dimmer to the point that the couple could barely see themselves while dancing and most of the guests saw nothing except candlelight reflecting off the bride's gown. For this "very romantic" lighting, I had to set the gain switch to to high even with 24p and 1/24th. The couple were fine with this because I had explained in my contract that video in dark rooms can appear grainy and washed out.)

Wesley Cardone November 2nd, 2010 12:10 PM

I will almost always shoot at 1/30 sec when in 60i or 30p and 1/24 for 24p for weddings and receptions. I don't mess around with changing it but just leave it at that setting for the entire event. Three years ago I had one scene that showed motion blur for one movement and that is the ONLY time I have ever seen it in footage that I wanted to release and that was shot with a Z1. Usually with the Z7 I can continue to run zero video gain.

I have found, though, that there is a difference between a low-light room with DJ lights flashing and a truly dimly lit room with maybe candles at the tables. I still get good footage with the DJ lights running although I may run +6dB. However, I did a wedding this season where the reception room was truly dimly lit and they had a bunch of candles at the tables. I knew from experience that shooting at 1/30 sec and 0dB gain would give me a lot of video noise so I upped the gain to +9dB which was still not enough. The resulting footage had very noticeable grain with video noise that I probably could have gotten away with releasing since I had already explained to the couple that the lighting was too dim. It didn't really look all that bad but it made me sick. I went ahead and ran some de-noise software that I have to clean up that grain and the result looked VERY nice. The downside is it took about ten hours of quad-core cranking to process the footage with the de-noise effect added.

Last year I shot a wedding reception where they had a crushed black velvet backdrop. The backdrop adsorbed all of the light and the video turned out hideous. De-noising it made all the difference.

Allen Bartnick November 2nd, 2010 06:08 PM

Wesley, what de-noising software did you use. I'm editing in Premiere Pro 5. Thanks

Wesley Cardone November 2nd, 2010 06:37 PM

I use Neat Video in both CS3 and CS5 but there are others that may be equal or better. I believe all of them including Neat offer demo versions so you can try them to compare. Neat has a 64-bit version for CS5.

I can tell you that Neat works very nicely and costs about a hundred bucks. You have to have at least one frame with a large uniform area such as a wall with no texture. Neat will be able to tell you if the frame you are getting your noise profile from will work or not. If not you can scan through that clip or other footage taken under the same conditions for a uniform frame to get its noise profile from. All you need is a small square somewhere in the current frame that is about a tenth of the total frame size.

Search in yahoo or google using "neat video denoise." Other names are Topaz and Red Giant and there are probably more. I believe that ALL of them have demo versions.

Allen Bartnick November 2nd, 2010 08:49 PM

Thanks Wesley, I'll look into them.

Keith Forman November 7th, 2010 07:16 PM


Originally Posted by Allen Bartnick (Post 1583397)
Don, I have been shooting in 60i, should that matter?

In 30i with 30th of a second shutter you will get motion artifacts (really bad in my opinion). 30P will match the fields and be fine--though it will look like 30p rather than the more traditional look of 30i.

Jay West November 8th, 2010 01:03 AM

There is a certain amount of personal judgment at play here in using 1/30th as your shutter speed, Something that doesn't offend my eye can be the video equivalent fingernails on a chalkboard to another videographer. And vice versa. What I suggest to Allen is that he get a couple of friends to act the parts and and run a little test footage. See what he thinks of when he compares 30i and 30p (and/or 24p).

Seems to me that I'm going to get some kinds of artifacts whether I shot 30i or 30p at 1/30th or 24p at 1/24th. They may be different artifacts but "some" are unavoidable.

The question is not whether I get artifacts but whether they are objectionable.

I mean objectionable to the customers.

I've been shooting wedding videos for 17 years now. Like Don --- who works with PD170s --- I used VX2000s and also ratcheted down to 1/30th in dim rooms. (I still do this with my HD cams.) Did this without a complaint from a customer, ever. At least about anything like a motion blur or other artifact. (Got some expressions of regret about how dark the wedding planner had made the room but nobody even noticed a motion artifact.)

What the customers seem to want is to be able to see and recognize themselves. You do what you have to get them that. Sometimes, you just drop down to 1/30th while shooting in 30i. (That's what used to be called 60i; the arbiters of vocabulary have decreed this change). Sometimes you go to 30p or 24p and deal with look that results from those formats.

Another thing about dark rooms is this: the darker the room, the slower people tend to move. A first dance in a really dark room tends to be really slow, almost static. Not a huge amount of motion to artifact.

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