View Full Version : Ghosting on the XF300


Milton Raposo
July 15th, 2010, 12:58 PM
I've just been doing some tests on the XF300 on 30p and 24p and I'm getting some ghosting. You know,movements of hands and things like that that leave that trailing effect.

What am I doing wrong? What should I be doing? Is it my shutter speed?

Barlow Elton
July 15th, 2010, 01:03 PM
My first guess would be to turn off noise reduction. That's probably the culprit.

Steve Phillipps
July 15th, 2010, 01:26 PM
Not like I'm getting with the Panasonic HPX371 is it ? http://www.dvinfo.net/forum/panasonic-p2hd-dvcpro-hd-camcorders/481778-hpx371-noise-issue.html

Nick Wilcox-Brown
July 15th, 2010, 02:18 PM
Milton,

Can we see a clip or couple of stills? I have not noticed anything on my clips.

Barlow, there are advantages to leaving NR on auto, especially at higher gain settings (according to Alan Robert's report).

Randy Panado
July 15th, 2010, 02:26 PM
Are you talking about high shutter stuttering or actual ghosting?

Tom Bostick
July 15th, 2010, 03:43 PM
cant tell you much without a screencap

Milton Raposo
July 16th, 2010, 10:00 AM
i don't have a clip to hand right now but it's that effect you get when the clip is interlaced. let's say it's a clip of someone waving their arms. the arms leave a very slight trail.

i will try to post a clip later today.

Milton Raposo
July 16th, 2010, 10:03 AM
Are you talking about high shutter stuttering or actual ghosting?



ghosting. but it's not massive but just enough to be noticeable.

David Chilson
July 17th, 2010, 05:56 AM
Mitch,

I get the same thing on my XHA1s when I shoot in 24p with people moving their hands. Here is a link to a video where it happens. I think it may be the back and forth motion.

Spring Browns with Randy Calus on Vimeo

Guy McLoughlin
July 17th, 2010, 09:47 AM
I get the same thing on my XHA1s when I shoot in 24p with people moving their hands. Here is a link to a video where it happens. I think it may be the back and forth motion.

This looks like junk frames from footage that has not been properly reverse-telecined. I used to see this with footage from my Canon HV20 or Panasonic DVX100B before I learned how to properly reverse-telecine my footage.

24P footage should just look blurred with fast motion, there should never be a double or ghost image.

Milton Raposo
October 14th, 2010, 12:17 PM
Finally got some footage up. Look at the first artist, at the start of his presentation. He waves his hands a bit and leaving that trailing effect.

The Bermuda National Gallery Biennial 2010 on Vimeo

Nick Wilcox-Brown
October 14th, 2010, 12:51 PM
Try taking a still image in low light at 1/48 or 1/24 second and then wave your arm around. The result WILL be blur.

To freeze a moving object, one has to use a shutter speed of 1/250 or 1/500th minimum ie 10x the speed you are using to shoot smooth video.

This is not a camera issue, it is physics.

Nick.

Peter Moretti
October 14th, 2010, 01:07 PM
Finally got some footage up. Look at the first artist, at the start of his presentation. He waves his hands a bit and leaving that trailing effect.

The Bermuda National Gallery Biennial 2010 on Vimeo (http://www.vimeo.com/15808794)

Milton,

Are using some type of low light or cinema mode that lowers the shutter speed? It looks to me, FWIW, like 24P w/ a 24fps shutter. Normally you'd use a 48fps shutter.

Doug Jensen
October 14th, 2010, 01:55 PM
I agree with Nick and Peter, the wrong shutter speed has been used. That's all that's going on.

Milton, why don't you use Canon's XF Utility software to examine one of the offending clips and let us know what the shutter speed actually was. This is a perfect example of how metadata can be helpful -- and the XF305/300 saves TONS of it.

Guy McLoughlin
October 14th, 2010, 02:29 PM
I've just been doing some tests on the XF300 on 30p and 24p and I'm getting some ghosting.

This looks like normal motion blur from using a slow shutter speed. Based upon your sample, I would be far more worried about the sound quality you are recording. ( i.e. The sound is weak, has a limited tonal range, lots of LAV mic rustling sounds )

Peter Moretti
October 15th, 2010, 08:33 AM
Guy, BTW if you have any tips on limiting clothing noise with lavs, I'm all ears... so to speak. :)

Guy McLoughlin
October 15th, 2010, 10:54 AM
Guy, BTW if you have any tips on limiting clothing noise with lavs, I'm all ears... so to speak. :)

There's a great hands-on location audio book that really helped me improve the quality of my audio work:

Location Audio Simplified - Trew Audio (http://www.trewaudio.ca/store/product.php?productid=768&cat=0&page=1)

It covers all kinds of typical location audio problems, including several different ways of securing a lav mic to eliminate clothing noise. Looks like a new updated version is due very soon.

My 2cent suggestion is to follow one of two options:

1- Secure the lav mic so that it is visibly exposed ( nothing covering the mic head ) which may not be as pretty to shoot, but you won't pick-up clothing sounds.

2- Use "Mole Skin" ( you can pick this up in any pharmacy in the "foot" department ) to create a small pocket to securely hold the lav mic, this can be taped to the speaker's skin or pinned to the inside of a jacket or shirt. It's a bit of a hassle to set-up and take off, but done properly you can effectively hide the lav and not get the normal clothing sounds interfering with your audiio.

What lav mic are you using ?

I use Sennheiser G2 100 UHF packs with TRAM 50 lav mics, which are my favorite general purpose lav. ( especially because you can clip the TRAM mic to face towards the vampire-clip which effectively limits most room noise while still picking up great audio of the speaker ) I also own a Sanken COS-11x which is an outstanding sounding lav mic ( almost as good as a condenser pencil mic ) but it picks up everything in the room, so I only use it in very quiet environments. I also own a Sennheiser MKE-2 Gold lav, which sounds better than the TRAM 50, but is a little more noise prone than the TRAM but not as much as the Sanken. I threw away the lav that came with the Sennheiser UHF kit as it was absolutely crap compared to my other lav mics.

One other nice bonus when using Sennheiser UHF lav mics, is that they will plug directly in to many small digital recorders like the Olympus LS-10/11, so you can bypass the whole UHF business, and have several people mic'd up with a digital recorder in their pocket or clipped to their belt. I plan on trying out the Zoom H-1 as a cheap solution ( $100+ recorder ) to mic up 6-10 people with lavs. ( the sync might be a bit of a pain, but I've been doing this for years so I am pretty quick at this )

Milton Raposo
October 21st, 2010, 08:42 AM
Guys, thanks for the help. I'm sorting this issue out. It's obviously my own handicap.

As for the audio, yes I know. I don't think I bought a robust enough lav system but as for that woman in the video and the crappy audio, I don't know what happened but she must have done something because when I put it on her and I listened thru the headphones it did not do that.

Fortunately it's just her.

Bill Weaver
November 23rd, 2010, 02:02 PM
I've noticed ghosting as well, reddish or greenish "lags" when there is camera movement when shooting in minimal light. Shuttter is normal, Noise reduction off, images stabilization off.

Now -- I'm realizing that this is the lagging effect of the TV screens I've been evaluating the camera on. On a computer monitor, the effect is barely visibile.

Still testing.....