Problem with capturing P2 data

Daniel_GreySkyFilms

Daniel_GreySkyFilms

New member
Hi all,

Our company is having a very strange problem with our HVX 200. Here it goes:

In any format (480i or 720p, PN, etc.), when we look through the viewfinder and LCD, a well-lit subject looks normal. However, when we import the footage using P2 contents manager into our non-linear editing system (using Adobe Premiere CS3), the footage looks darker in certain areas (there is less detail). For example, take the example of a person wearing a black coat. In the viewfinder/LCD, we can see the ruffles and wrinkles, but in Premiere, it appears as one solid black blob.

Interestingly enough, when we open the P2 video files in windows media player, the footage looks normal (so after p2 ingestion, the computer plays the files normally). It is only after we import it that things get funky. To further complicate things - (1) we've never had this problem up until 2 weeks ago (2) the problem persists when using a Firestore 100 drive and (3) the problem DOES NOT occur when we record to tape and digitize. One more thing - we've also reset the camera to factory settings and still have this issue.

Anyone who has any clues to this mystery - we would greatly appreciate the wisdom. I have not been able to find any information about this issue online.

Thank you.
 
Hi Daniel,

As you probably already know, don't use the LCD or Viewfinder on camera to gauge exposure correctly. You have your zebra's that can give you a good indication of where your exposure is.

That be said can you attach the 200 to an external good quality HD monitor direct. Then you will know straight away whether it is an exposure problem or during the import stage the software product is doing something to the imported video.
 
Hi Stephenh,

Thank you for your response. We will try to use an HD monitor to test the camera.
While we do sometimes use an HD monitor, exposures without the monitor have been close enough to imported footage in the past. However, now everything is significantly darker when importing P2 footage. This is NOT the case when using a DV tape. This leads us the conclusion that it is probably not the camera, although we can't rule this out completely.

Do you have any possible explanations for import stage errors?

Thank you
 
Hi Daniel,

Can be a tricky one. I remember when I used to use FCP, any earlier version before moving to Avid Media Composer. It used to change the Gamma of the video on import. It could be something else but I have seen a lot of issues over the years with different software and import gamma settings.

That is the reason that I suggested that you hook up the camera to a good HD monitor, or Broadcast Monitor if you can, just to confirm that the captured image is on the mark and somehow the software import is changing the gamma on import.

I shoot more than I edit, so one suggestion is if you find that the footage is fine, post on the forum for the software you are using and ask for some help from people using that particular editing software.
 
This sounds like a Setup issue (7.5 - black levels), or it could be an RGB vs. 601 color space. I don't know enough to explain on that, but search those terms and you might find an answer. Have had similar problems when getting DV footage from an AVID to Final Cut. Also, maybe check your timeline or project settings, they could have some sort of setup being added. Not familiar with Premiere at all, so don't know for sure.
 
That's the other thing that you people in NTSC land have to deal with that we in PAL land do not. Good call eagleye.
 
RE: black levels, our first instinct was to make sure the setting was normal - 7.5. However, could you please elaborate on RGB vs. 601 color space?

Thanks eagleye.
 
Daniel_GreySkyFilms said:
RE: black levels, our first instinct was to make sure the setting was normal - 7.5. However, could you please elaborate on RGB vs. 601 color space?
Click to expand...

Here's a link to an AVID community forum on RGB/601:http://community.avid.com/forums/p/61280/343714.aspx

If you google rgb vs 601 color space there are several links on the topic.

You should be using 0 IRE in your camera menu and applying setup on the timeline in your NLE if you need it (i.e going to broadcast). Search this forum for extensive discussions on that.
 
Thanks DGW. I will look into this.

I appreciate everyone's posts. I have an update on this issue.

I think we've ruled out the software side. For one, the P2 footage looks the same (less detail in dark areas) on all of our machines at work (4 PC's running Premiere), as well as on my Mac with Final Cut.

To complicate things futher, I took Stephenh's advice and hooked the HVX up to a high quality monitor - the result was that the feed looked normal. This is very odd because the camera seems to be working fine, and the footage is still dark-er on 2 different programs on 5 different machines. We are totally stumped. The only thing I can reason is that maybe its the P2 cards.

We are going to try to borrow another HVX to see if we have different results. I will post my findings here. If anyone has any other advice, we would greatly appreciate it.
 
Hi Daniel,

When you say "the result was that the feed looked normal" do you mean a live feed to the high quality monitor, or playing back what is recorded to the P2 card out through the component interface of the camera to the external monitor.

The only way to make sure that the camera is recording correctly is to play back recorded footage and not a live feed.

I still think that the conversion error is in software, but will hold my tongue, as I have been cought out on something similar like this before.

Steve.
 
Both live feed and playback from the P2 card look good on the monitor. I wonder if it could still be the P2 card?

Our last guess is the harddrive itself - we are using MyBooks with USB connection. We're going to try another harddrive. We'll post findings here.
 
How could it possibly be the P2 card? It's a digital storage device, that stores ones and zeroes.

The problem is almost unquestionably in the gamma of your computer monitor. Obviously the footage is being imaged and recorded properly because it's showing up properly on the live monitor.

So if it doesn't look right on the computer, it's the computer's fault.

I pretty much guarantee you that if you go into post and lighten up the footage, you'll see that all that shadow detail is there.
 
Wow Barry Green - I just got done with your HVX manual. We actually looked through your book for solutions.

I think you are right, the image is being recorded properly as shown by the monitor. However, the very odd issue is that the footage looks 1-2 stops darker than what we are exposing for on our computers at work (4 PC's running Premiere), and also my personal Mac running Final Cut. We have been lightening the footage using filters but it is an arduous process that we never had to perform up until a few weeks ago. What could possibly be the explanation?

Thank you in advance.
 
Are you using the zebras and waveform monitor to make sure you're capturing the footage at the actual proper level? Are your monitors calibrated to make sure they're accurately displaying the image?

Sounds like something is "off" somewhere, either your computer monitors are calibrated too dark or your video monitors are calibrated too light.
 
I don't think its the monitors - how could it be if our captured footage from a DV deck looks good? We're lost. We may send our camera in for analysis.
 
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