DV Info Net

DV Info Net (https://www.dvinfo.net/forum/)
-   Sony XDCAM EX Pro Handhelds (https://www.dvinfo.net/forum/sony-xdcam-ex-pro-handhelds/)
-   -   Breaking the rules (https://www.dvinfo.net/forum/sony-xdcam-ex-pro-handhelds/468773-breaking-rules.html)

Greg Hawkes December 2nd, 2009 05:33 AM

Breaking the rules
 
OK I think this post will be controversial.

I had been waiting for two Tiffen TI IR filters for my two EX1s.

My wife has just bought some new trousers, Black and grey and navy blue.
They were hanging on display in our bedroom when the thought crossed my mind.
I wonder what the EX1 would make of the colours.

So here we go:
Preset 5600k wide shot black not black close up black-brownish.
I did not film the scene so sorry no screen grabs.
Manual white balance smilar results.
ATW similar results.

I'll cut to the chase.

I got good results ie black is black wide shots and closeups by taking a white balance without a white card just simply aiming the camera in the direction of the trousers and pressing the front (EX1) white balance button.

I the tried lighting the scene with a single 200 watt QI video lamp (photon beard)
same results as above.

Taking what seems to be a composite white balance gave the best results. Black is black!

I expect to be shot down in flames but I am suffiently encouraged to cancel my Tiffen order and use this white balance method for my next three jobs (next week)

Vincent Oliver December 2nd, 2009 06:58 AM

Maybe your wifes new trousers are 100% cotton and as such black will not show up as "brown" . Take my advice and keep your order for the filter going.

Take a look at my clip, bear in mind that my jacket is pure black (man made fabric) as are my trousers (cotton)

printing and scanning DVD

Piotr Wozniacki December 2nd, 2009 07:27 AM

Greg has a good point here, I can assure you...

Nick Wilson December 2nd, 2009 10:19 AM

Hi Greg

When you did your white balance, did the trousers fill the frame or was is a combination of them and some other background? If so, what other colours were in shot?

Having white balanced in this way, how was the colour reproduction of a normal scene? Were you getting accurate skin tones?

If you get a chance to repeat this, frame grabs would be very interesting.

Cheers

Simon Wyndham December 2nd, 2009 10:38 AM

The test doesn't really mean much. I'd shot countless interviews with people on the EX3 without any problems. Until two weeks ago when I got brown clothing that was supposed to be blue.

A black leather jacket will show as black, but a black jumper worn underneath made out of certain types of material will show as brown.

In short, don't cancel your Tiffen filter order!

Paul Inglis December 2nd, 2009 10:51 AM

I have had similar experiences to Simon, where certain fabrics are, as seen while others have suffered the far red contamination.

I have tested my Tiffen T1 IR on an item of clothing I knew to suffer the far red contamination problem is now looks a deep rich black apposed to the mucky brown previously.

If you cancel your filter you’ll end up kicking yourself.

David Esp December 2nd, 2009 11:32 AM

IR Filter is a Neccessity
 
Infra-Red (IR) blocking? It all sounded esoteric at first, or maybe something to do with preserving modesty. But then I realised that's why I couldn't get my given EX3 and Z1 footages to match, their browns had looked different somehow, "what colour were they really" I started to wonder. If I graded the browns to match then everything else was out...

It's one of those things that only tends to matter (or even get noticed) when e.g. matching different cameras or obtaining "perceived as accurate" colours on branding / uniforms. In the case of IR the lighting can affect it too. There are other camera difference issues, some fixable/patchable in post, but this is a fundamental one because it destroys information (what's really brown?). Fix by Secondary colour correction (of course I tried that) is hit-and-miss (depends if similar colours are elsewhere in the scene) if not risky (unless you want to rotoscope everything).

I ordered one just now, for avoidance of embarrassment, greater quality, less fiddling in post and maybe even slightly faster rendering (in that order).

Dave Morrison December 2nd, 2009 11:52 AM

I'm still planning to get a T1 but I have a question for those who have received them already. Are you leaving the filter in place all the time? How much light loss is there with the filter in place? Is there any color shift with this filter (prior to WB'ing)?

Ed Kukla December 2nd, 2009 12:00 PM

your test means nothing

Many black surfaces and cloth will photograph black. But some will not. Guaranteed. Just finished a shoot where it looked like everybody worked for UPS, and they were wearing black clothing.

Paul Inglis December 2nd, 2009 12:15 PM

Quote:

Originally Posted by Dave Morrison (Post 1455154)
I'm still planning to get a T1 but I have a question for those who have received them already. Are you leaving the filter in place all the time? How much light loss is there with the filter in place? Is there any color shift with this filter (prior to WB'ing)?

Hi Dave,

To answer your questions;

1. I leave my filter on all the time now
2. There is a 1/3 stop loss
3. Colour shifting – It fixes the far red contamination and everything looks good

Dave Morrison December 2nd, 2009 12:50 PM

Hi Paul. Thanks for the reply. On Question 3, I understand the function of the filter, but do you see any immediate color shift when you attach the filter or does it just seem like putting on a ND filter?

Bob Jackson December 2nd, 2009 01:14 PM

I was thinking about buying one too.
Went to the reseller and he advised me against it.
Told me i could easily correct in FCp 3 way color corrector.
I took his advise and have not looked back.

Vincent Oliver December 2nd, 2009 01:51 PM

Perhaps you could share the secret of colour correcting the IR problem with all of us Bob. But only if you can guarantee that any genuine browns in the picture stay brown. :-}

Nick Wilson December 2nd, 2009 02:37 PM

The far red problem is that the camera is picking up a colour which to the human eye is invisible. In some ways it is the same as flooding the scene with UV light - some objects would fluoresce and to the eye appear as a different colour. With colour correction in post it would be possible to correct for these, or for the black as brown, in isolation but:

- if the same colour is genuinely present in the scene, it is going to be very difficult to remove the unwanted and retain the correct (and how would you know, as editor, which is wrong)

- the aim of the camera is to record accurately the scene. Some colour correction may be needed for artistic reasons but the camera should not be adding to the workload by introducing additional errors

Sony, in Alister's article on their website, are saying that the red handling in the EX1 was a problem and in the EX1R it has been addressed. This is not a selectable option - they are sufficiently confident that the EX1R approach is an improvement that they are giving customers no choice. It therefore seems reasonable that they recall the cameras already sold and upgrade the filter, or as a minimum provide T1 filters.

Dave Morrison December 2nd, 2009 05:13 PM

P.S. Loved your work with The Cars, Greg! ;)


All times are GMT -6. The time now is 04:09 AM.

DV Info Net -- Real Names, Real People, Real Info!
1998-2024 The Digital Video Information Network