getting good "video balance"

[Steve Nunez]

Hello fellow XL'ites....

...I'm having a little trouble finding just the right setup to achieve the "look" I'm looking for. I shoot manually and use the "Zebra" stipes at 100 to warn me of overexposure- problem is I can't seem to get the best balance of proper subject exposure (mainly birds at this time) without blowing out the highlights (Zebras indicating overexposed highlghts) If I juggle the shutter speeds or aperature I'm consistently getting a darker image than I'm hoping for, and AE doesn't work in M mode....the resulting video isn't bad but just not the "perfect" look I'm trying to achieve (bright, well exposed subject without blowing out highlights- Discovery Ch type video)....I can't help but feel I'm missing something on the settings. I'm using -3 on the gain with both custom WB settings and the "Sunny" WB setting and sometimes a custom preset (a little sharpening and saturation.) I've been shooting with an EF adapter and Canon 75-300 USM III lens (with Hoya UV filter) and the images are razor sharp (even at 300mm!~ which turns out to be 2160mm) for long range shooting (but you just can't beat the stock lens' IS feature- works great!)
Am I asking too much of the XL1S and this is perhaps as good as I am going to get- or can any forum contributors recommend a setting to try?
(let's assume well lit outdoors and using the stock Canon lens)

Overall I'm very satisfied and using the EF adapter with even a low priced Canon 75-300 USM III lens really opens up alot of long distance shooting possibilities (the sharpness is incredible.)

Ohh- one quick question for you Canon camera shooters- are all Canon lenses controlling the aperature via internal electronic mechanisms- or do some Canon compatible lenses (Tokina, Tamron, Sigma) have manual aperature rings that can be adjusted on the fly (like Nikon)?
~ The Canon lens I bought can't be adjusted manually- I have to use the XL's Iris Select switch- which I enjoy- but I'd like a manual ring to make snap changes quickly...anyone know if the 3rd party Canon compat's are like this?

Thanks to any and all whom respond- much appreciated.

[Adrian Douglas]

Steven,

Try using a polarizer. It will cut down the glare and saturate the colours. Also maybe set your zebras to 90-95 IRE.

[Bill Ravens]

Easy question first: I know that with the older FD Canon lenses, many aftermarket lenses did not incorporate the automatic aperture linkage, for cost considerations. It was cheaper to make as a manual lens. My guess is that the newer aftermarket EF lenses shouldn't be any different....that is to say they sould be available as a manual lens only.

On the question of CCD latitude: I 've learned from this forum that setting the zebra to 90 or 95, instead of 100, gives me an earlier warning about blowing out the highlights and leaves me a little headroom to work with. Yes, this will result in loss of detail in the shadows, but, it's an acceptable sacrifice, in my opinion. I've been learning more and more about fixing this problem in post, to make use of that little headroom I left myself with the zebra setting. Vegas Video 3 has an option to view the histogram of an image overlayed on NTSC "legal" limits. By selectively and carefully applying contrast and brightness filters while watching the histogram, I can optimize the image....i.e., improve the detail in the highlights, without crushing the blacks. At least, I can set up the filters to use the whole dynamic range available. Many times, the histogram shows that I'm not using the available range. It's a delicate adjustment...like walking a tightrope. But, the final tweak can be done in post.

[Steve Nunez]

Thanks- I'll try a Polarizer- is this a standard type or the rotating type I've read about?

And what would using a lower Zebra IRE# do in terms of exposure? Does it mean it will warn later than sooner as to overexposure- I guess I can look this up in the manual.....thanks for the response.

[Steve Nunez]

Thanks both Bill and Adrian.

I'm using Final Cut Pro 3 on a Mac and it's full of new enhancements for DV editing- I'll have to look into post video correction with a histogram (see if it's available- or something like it~~ maybe that's the Vectorscope??)...with digital photography- the histogram was a most vital indicator and adjustment tool-

thanks for the tips guys.

[Bill Ravens]

Also...one more thought. I set my black level at -1 or -2 to try to recover as much shadow detail is possible. The XL1s nominal black level setting is about 7.5 IRE. DV can use everything down to 0 IRE. Therefore, the total range is optimized by reducing black level one or two steps.

hope this helps.

[Adrian Douglas]

I use a circular polarizer with the standard 16x lens. It works really well in cutting down the harsh glare from intense white areas like snow and the foam of the surf. You can use a circular one with all both the 16x auto lenses, the 16x manual and the 3x WA lens as the front elements don't rotate.

With your 75-300 you'll have to use a linear(standard) polarizer as the front element of the lens rotates so every time you zoom or focus your polarizer setting will change. I used to have the IS version of that lens and it was a pain in the arse with a circular polarizer.

You might try the 70-200L lens. The image is much clearer and the front element stays put. It does cost a bit more but in my opinion it's worth it. Now that there is an IS version on the market you can pick up the older non-IS version second hand pretty cheap.

[Jeff Donald]

Hi,

Circular and linear polarizers differ in the method they use to polarize light. All autofocus cameras ( either 35mm or video) require circular polarizers. Linerar polarizers will advirsely affect your AF and sometimes your exposure.

The black level can be set to 0 ire if your video will not be broadcast. TV stations will adjust your black level back to 7.5 (NTSC requirement) before putting it out over the air. However, if your work is going to tape, internet, DVD etc. you can extend the blacks and thereby extend your contrast range. If you want a film look this helps by getting the contrast range of video closer to film.

Depending on what I am shooting I set my zebra level differently. When I am doing hawks in flight I set by zebra to 80 to 85 and set black to 0. This keeps the sky from burning out and keeps the bottom of the wings (in shadow) from blocking up to bad. But most of the time I leave it at 90 to 95 ire.

In FCP I use the gamma control some to strech the contrast range of the image. When working with gamma you can not use a computer monitor. The gamma on a PC monitor is usually set around 2.2 to 2.4 The gamma on a Mac monitor is set around 1.7 to 1.9 This is closer to NTSC but it is not exact. This is one of the reasons that videos watched on a computer screen do not match a NTSC monitor.

Jeff

[Bill Ravens]

jtdonald...

what you're saying is technically correct, but the devil's in the detail. Yes, NTSC has a lower limit at 7.5 IRE. The DV standard pretty much defaults to 0 IRE, however. The XL1s is the only prosumer DV camera I know of that lets you raise it to 7.5 IRE. To do so, however, will further reduce your capture bandwidth , aka latitude. My experience and advice is that you shoot at 0 IRE then let the post processor make sure you're NTSC legal. The processor will remap the colors, with a knee if you wish, so the shadows aren't crushed. It's a MUCH more reliable way of getting your cake and eating it too.

[Jeff Donald]

Hi,

I think we said the same thing but got mixed up on 0 ire and 0 camera level setting for black level. When I have the XL1s set to 0 in the menu setting the output is 7.5 ire as best as I can tell. This is measured at the RCA out terminal into a Leader Waveform/Vectorscope. Unless what I am shooting is specifically for broadcast I shot with the camera set to -1 in the menu which gives a result close to 0 ire. I try never to shot below 0 ire because that gets video into the sync and can cause problem later.

Jeff

[Bill Ravens]

exactly, Jeff.I've gotten the same result with a software vectorscope and waveform analyser.

[Rob Lohman]

Anyone knows if such histogram functions etc. are available
in Premiere or After Effects? Or do I need to use some plugin?

Wasn't PAL DV 0 IRE instead of 7.5?

[Bill Ravens]

Until I switched over to Vegas Video 3, I was using Premier for my color correction. Unfortunately, premier doesn't have a native analyzer, so I was using Video Finesse, a plug-in from Synthetic Aperture. This really is an excellent vectorscope, analyzer and color correction tool all in one. It will allow you you adjust the slope, knee and rolloff of the luminance curve, as well as the individual chroma colors, R,G and B.

[Jeff Donald]

I use Video Finesse plugin for AE occasionally now. I used to use it alot but old plugins not work in FCP 3 under OS X. The color tools are very powerful. I don't know if there is a PC version but Evological has a product for Mac, VideoScope ( http://www.evological.com ) that is a stand alone waveform monitor/vectorscope.

Jeff