View Full Version : Possible problems when setting shutter speed to 30


Allen Bartnick
October 28th, 2010, 03:45 PM
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.

Allen

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
Allen:

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
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.

Rob Morse
November 10th, 2010, 11:32 AM
I thought I had heard you can't put 30p on a Blu-ray, is that true? I haven't tried shooting in 30p but I would like to.

Wesley Cardone
November 10th, 2010, 01:34 PM
Blu-ray only allows for 24p and 60i. It seems mighty strange that 30p was left out.

I've read that there are workarounds for getting 30p onto Blu-ray but never found an actual explanation. You could de-telecine your 30p footage to 24p but that would be dumb and defeat your purpose.

Doug Jensen
November 10th, 2010, 05:33 PM
It's not so strange that 30P is left out. It's not needed. A 30P program that is converted to 60i looks exactly the same as the original 30P. What you get is two identical fields that look the same as one frame.

Doug Jensen
November 10th, 2010, 05:37 PM
I haven't tried shooting in 30p but I would like to.

Rob, once you make the leap to 30P you'll wonder why you ever used interlaced with your Z7U. Interlaced is outdated technology that does not have a place in today's workflows and HDTVs. Try it, you'll love the look of it -- and so will your clients. Almost nothing on broadcast TV is shot interlaced anymore except for live sports and news.

Z7U / S270 Training
Vortex Media: VIDEO & PHOTO Tools and Training (http://www.vortexmedia.com/DVD_Z7U.html)

Rob Morse
November 18th, 2010, 09:20 PM
Thanks Doug. By the way, I really found your training DVD very helpful when I got my camera.

So, if I shot in 30p, what is the best method to get it to Blu-ray?

Doug Jensen
November 19th, 2010, 09:05 AM
Rob,

I'm glad you liked the training DVD.

I can't tell you how to get your program to Blu-ray because I haven't done it, and it really depends entirely on your NLE and authoring software anyway. All I can say is that I would still edit with a 30P timeline even if ultimately I had to convert the final video to 60i for the Blu-ray. Like I said, it will still have a 30P look.

Rob Morse
November 19th, 2010, 05:00 PM
Thanks, I'll give it a try.

Wesley Cardone
November 19th, 2010, 07:11 PM
Doug,

I, also, have the Z7 training DVD and have found it quite informative. There is one thing that I do differently from what you suggest in using the profiles. I would follow your suggestion on multi camera shoots if the other cameras were Z7s but I only have one Z7. Therefore, I shoot using the factory standard and apply my color dressup as an effect in post.

On producing for Blu-ray, could you then make your 30p footage 60i at any step along the way to the disk? Consider for example, in a two-step process where you export the timeline first to AVI and then transcode the AVI to m2v. Could you export at 60i off the timeline into the AVI so that then the transcode to m2v would already be 60i to 60i? Or export off the timeline at 30p but transcode the resulting 30p AVI to a 60i m2v? That sounds kind of complicated but I don't know how else to suggest an example. I'm guessing that either would work equally.

Doug Jensen
November 20th, 2010, 06:43 AM
Hi Wesley, if grading the footage in post and then waiting for it to render works for you, go for it. Of course, any gradiing or rendering will always degrade the quality of the footage, not to mention the time it adds to the edit, and that's why I prefer to get the look I want in the camera a the time of shooting. Everybody has their own workflow and I completely understand your choice to follow a different path.

I'm not qualified to answer your post production questions about Blu-ray authoring, because I never have any reason to distribute on Blu-ray. But I will say that I think your suggested workflow has too many steps.

Wesley Cardone
November 21st, 2010, 06:20 AM
Doug,

You are correct about having too many steps in the workflow. I should have thought ahead and put up a more generic workflow. My specific circumstances necessitates the extra steps.

I always shoot in HDV with DVD release but only release to Blu-ray occasionally. If I only released on Blu-ray the steps would be simpler. The problem is with that nasty down conversion of HDV to DV and getting an acceptable color space conversion. If I transcoded 1080 HDV in the AME or MME (Matrox Media Encoder) directly to MPEG-2 m2v I would get jaggies. What I have to do is use the PPro ME to create a 1080 AVI from the timeline and then import that into After Effects for transcoding. This at least has a benefit in that I can then get the convenience of a transcoding queue which only became available in PPro starting with CS4. I therefore let AE transcode my HDV to h.264 at the same time although the CS3 AME or MME would give excellent results directly. I can load up a day's worth of transcoding to then run overnight generating both MPEG-2 and h.264 versions for any given movie. I am still using CS3 because of the Matrox RT.X2 card. Matrox just released drivers for CS5 this week but I will still wait for the dot release which will fix the bugs which, no doubt, are in the initial release.

I have CS5 loaded up on a dual-boot machine and have been using it for some isolated operations and am deffinitely chomping at the bit to get rolling with regular CS5 use. I use CS5 Encore exclusively for all of my authoring work.

Doug Jensen
November 21st, 2010, 07:26 AM
Wesley,

Wow, that sounds complicated. I don't use any of the software you're using so I can't follow your workflow at all, but it sure sounds overly complicated. I use FCP and Compressor and I'm 100% sure that I'd barely have to change anything in my workflow to get 30P burned on Blu-ray and looking great. But, like I said, I haven't actually done it.

I've had a Lacie Blu-ray burner sitting on the shelf in my office since December '08. Maybe it is time to tear off the shrink wrap and hook it up? I'd like to find time in January when I finish the project I'm working on.

Wesley Cardone
November 21st, 2010, 06:32 PM
Hi Doug,

I apologize for putting up such a complicated post that you missed the fact that if I were only producing for Blu-ray then it would be a straight shot. I would use the AME to transcode directly out of PPro to h.264. There is no color space conversion problem there.

I have a complicated workflow for HDV downconverted to DV and Blu-ray hitches a ride with it for convenience when I am also releasing to Blu-ray.

Doug Jensen
November 21st, 2010, 07:27 PM
I'm sorry I missed your point. I get it now. Thanks.

Rob Morse
November 27th, 2010, 07:01 PM
Wesley, I think you need to upgrade. I don't have to do any of that in CS5 or CS4 for that matter. I guess this needs to go in a different forum.

Wesley Cardone
November 27th, 2010, 08:52 PM
Rob,

I think my posts must be way, way too long. I mentioned earlier that I have CS5 and CS3 in a dual-boot configuration. Because I use the Matrox RT.X2 card I have been locked into CS3 until last week when Matrox finally released the CS5 drivers for RT.X2. Now that the drivers are out I just have to put in something like a GTX470 video card and then I can migrate fully to CS5.

Adobe started with CS4 a "Maximum Quality" check box in the AME which eliminates the need I have for a special workflow to get good color space conversion going from HDV to DV. The "maximum quality" option lengthens the transcode time but not any longer than what I have been getting in After Effects. CS5 will greatly simplify my workflow.

Rob Morse
December 2nd, 2010, 08:49 PM
Wesley,

I guess not being on everyday I lose track of the posts. I just saw the CS3 and forgot you mentioned the other.

I'm still using CS4 even though I have a 64 bit system and CS5. I thought I'd be doing that until Boris Red came out but CS5 with MPE is so much faster. I just started a new project and I'm using CS5. It seems more stable as well.