Using a polarizer with the XL2
 

I have a couple of quick questions about using a polarizer with the XL2. It seems to me that it make be awkward to use a polarizer on the XL2 because of the lens hood. Have any of you any tips on using the polarizer? Do you work without the hood when using it? How do you get around the problem of turning it if it is behind the lens hood. I have seen people say they use a linear polarizer with the XL2, is this used on manual focus only? Or is the XL2's focusing system different to 35mm systems that need a circular polarizer in order to auto focus?


Colin

auto focus would still require a circular polarizer. I use a polarizer on my XL1s, identical hood setup to the XL2. I reach inside the hood to set my polarization and then leave it while I shoot. If necessary, it's nothing to take off the hood for a shot...although you'll want a flag above the lens of some sort. I attribute alot of the color richness I'm getting with my XL1s to my polarizer, I don't shoot without it, indoors or out.

Do you use a multi-coated polarizer or a non coated? I was wondering if multi-coated made a big difference.

Colin

I went with cheap, but brand name ;) Works like a champ...someone will come along to argue with me soon, but I'm shooting DV and quite frankly, I don't believe is has the resolution to pick up the differences between the $25 one and the $50 one that I looked at. If I were shooting 35mm or even HD, the differences may be more evident and I might be a tad more concerned.

Locally I shop at Ritz and Central Camera for all my accessories.

I ALMOST always use a circular polarizer with my XL2. The bezel is nice and loose (unlike some) so I can spin it with a single finger while the hood is on. I also think that the color richness of many of my shots is because of (correct) usage of a polarizer.

Remember that just because it's screwed on, doesn't meanit's working. It has to be set.

DJ

Do you find that the color richness enhances the film look? Also, what custom settings do you normally use when using the polarizer? Any settings compensation needed or is it just a case of adding the polarized effect on top of the settings?

Colin

The polarizer will help get rid of "haze" from off axis light hitting the pixel next to the one that should be getting hit for a given piece of colored light. It enriches the color and allows you to get specifically the light information you want into the camera.

While this explanation may be technically wrong in some small aspect, they are my observations and work well for me. With the polarizer off, I get washed out colors even when exposed correctly, even under controlled lighting.

I find that it enhances the film look only in so much as professionally videography and cinematography cut that haze out. Richer colors are not indicative of film, necessarily, but haze IS indicative of amateur videography. So you're not making it look more like film as much as you're making it look less like amateur video.

As far as settings, I love the fact that the XL2 has them, but I don't use them. I like to get a well balanced, rich image in-cam and do anything and everything else in post.

Correction: The only setting I do use that helps the polarizer is to leave Gain at -3. It helps with grain and to drop out the blacks.

DJ

Thanks for the info. While I know all about polarizers there may be others that don't know the benefits.
I am actually working with a friend to try and recreate the look of a polarizer on an image in a Photoshop plug-in. We currently have a plug-in that will create photographic effects in one-click. Using the XL2 will also help me recreate other effects, as I can use the settings such as "knee" "color matrix" etc to be a base for other effects.

Colin

Thanks for the tip on the -3 gain setting. I will have to try that. You also have a very good point about making the footage look less amateur.

Colin

polarizer is good, but you loose about 1 to 2 stops.
coated polarizer are better since they transmit more light, but the price can go very high.
The best are Hoya , the pro1 serie, ultra-thin (glass is 1 mm instead regular 3mm) and the frame is only 5mm thick (usually between 7 to 10mm).
And it get the thread on the front , so you can add another filter on top of it.
turning the glass when insid the lens hood can be tricky, but usually the glass position, once found, does not change.

I was thinking of going the Hoya route but hadn't thought about the thin version. Do you think the thickness benefit outweighs the fact it is trickier to turn inside the hood?

i cannot help for the XL2 since i own a FX1.
I found a chinese guy who sell the hoya pro1 for cheap (usual price goes up to 200$ since the FX1 require 72mm diameter filters)
http://cgi.ebay.com/ws/eBayISAPI.dll...tem=7605705533
(not received yet)
For sure, you can get a regular CP (circular polarizer) for as cheap as 10$, so you want perhaps give a try with this kind of cheap stuff to make your mind.

The thin version of the Hoya (and others such as Tiffin, Lee and B/W etc) are not any different to the normal versions when considering quality of the actual filter itself. The main reason for using the thin and more expensive 'pro-thin' versions are when they are used on a wide SLR lens to prevent vignetting at the corners (that is sometimes caused by a thick filter housing ring).
I use the thin versions on some of my ultra-wide lenses bayoneted to SLR & DSLR bodies, but not for camcorders such as the XL2, as I have found no vignetting with thick ringed converters used on the 16X, 20X or 20X + wide angle converters.

The B/W are probably one of the very best brands for high quality glass filters, and I use them a lot, but I also have a selection of screw-on Hoya and Tiffin filters (and Cokin Grad filters with bellows) that are used for my SLRs and XL2 cameras.

A polarizer does not only cut through haze and deepen/enrich colours, but more importantly it cuts down glare for glass, metal objects, wet objects etc. The polarizer also acts like an extra ND filter - which is handy for bright light conditions; although I tend to remove it during dawn and dusk periods to gain back extra stops of light lost via the filter.
It will also cut through surface glare of water and these facts make it the most important filter that I own and is on the end of the 16X or 20X lenses most of the time.

There are non-coated, coated, and multi-coated versions of the polariser, and the coated version is OK most of the time, but the multi-coated version offers a slight advantage if you are not using a hood, bellows or matte box.

There are two main versions of the polarizer filter : Linear and Circular. The Linear was the first version to be made, but when cameras such as the Pentax LX Pro manual SLR camera was first produced (1980) - that had a metering system that split the light path - and later versions of autofocus cameras that also split the ligh path before making a metering reading - a new version called the circular polarizer was made to prevent inconsistant meter readings caused by using a normal linear polarizer filter.

I only buy Circular polarizer filters for all lenses used on my cameras - SLR film, digital, and DV camcorders.

You are a walking encyclopedia. Thanks for the history lesson.
I was thinking the thin versions of the filters would be better optically also, less glass, less distortion.
Out of interest have you tried stacking two polarizers? It may just be the ones I have for my 35mm gear , but if I stack two and rotate them to different angles I can get the same effect as a blue/yellow polarizer ie. boost blues or yellows depending on rotation. Also if my memory serves me right I read once that using two on video/film cams can act as a fade in/out filter when rotated during shooting.

Colin

Polarizer ordered
 

Well after reading the posts and looking around the web I have finally ordered a Hoya Moose Polarizer. It is a combination of circular polarizer and 81A warming filter. I think that will meet my needs.
Thanks for all the responses.

Colin

The Moose filter can provide a cast to some scenes, so be careful with it. I do use one for some of my still photography work, but tend to prefer a straight B/W or Hoya/Tiffin circular polarizer for the XL2 and then use in-camera settings to bump up the warm colour.

Thanks Tony,

I will keep an eye out for any problems with a color cast.

Colin

I tend to capture everything clean and effect it in post. I feel this gives me more options later, but some would argue that it adds time to post that is cumbersome.

I am still in the "Wow, this is so much better than my old camcorder phase" so I am still trying all the in camera/during shooting possibilities. I am sure that down the road I will settle into a way of working that will give me the best results.

There is no way that images or footage of a lot of my work done with a Polarizer, especially around water, could have possibly been done simply by filming straight and using affects in post.

My polarizer is part of catching the footage clean...I use that on the camera always...except at night, and even then if there's enough ambient light to catch the image with it on...after that I have clean footage to play with:

careful frame/light composition

polarizer to dial out glings and enrich colors

ND to bring light levels down as needed to keep iris open as far as possible

zebras at 90 til they dial out of subject and one more click down on the iris (so underexposed slightly)

minimize reds and whites in frame

edge enhancement turned off (down if your camera softens the image)

slight desaturation to let the camera compress the image more cleanly

Then I bring the footage in and post as necessary to get the look I want.

That is interesting about the compression being cleaner if the image is desaturated slightly. How much of a decrease would you call slight? One step? Two? Also why do you underexpose?

Colin

From what I understand of the compression, gradients are compressed mathematically horizontally for each line of the frame that is in motion between keyframes (someone correct me if I'm wrong). By desaturating, the algorithm will allow more detail to be captured to tape in the color regions as it is able to concern itself less with reproducing the full dynamic range of the colors and spend the tapespace on capturing more subtleties. Color can always be pulled up in post (I' a big fan of post being considered as part of the image gathering phase - besides, you'll be coloring any way...right?).

I turn the saturation slider down on my XL1s 1 or 2 notches...depends on the scene, more saturated color scene, 2 notches, reds, 2 notches, fairly flat scene, 1 notch. It's slight either way.

I underexpose due to the fact that whites clip in digital whereas blacks compress. It's easier to recover slightly dark footage than missing footage as the 101% and up whites get cut off and made 100%. It's analogous to film grain being washed away. In digital, we protect our whites the same way that film folks protect their blacks.

Is the difference really that noticeable? I can understand the exposure making a difference more than the saturation.
I think it is about time that there was an equivalent to shooting in RAW format on a DSLR in the DV world. That way you can get the best image possible in post. Obviously there would have to be a way to convert the RAW footage to some default NTSC/PAL settings for direct viewing on a TV/monitor.
Going the RAW route would allow for more details to be saved as the data saved would be at a higher bit depth. I think this is kind of what is happening with the uncompressed BNC output from the XL H1. Correct me if I am wrong.

Colin

You tell me:

http://www.yafiunderground.com/Video/Reel.mov

shot w/ canon XL1s using budget lighting (Home Depot) and natural light with white foam core reflectors for the exteriors. This is all uncorrected footage. I don't have permission for this music, I'll be replacing it.

To be honest I don't know that I could. Maybe in a side by side comparison. I am by no means an expert in filmmaking so some of the subtleties will bypass me.
I do like your results.

Colin

just received my Hoya Pro-1 Circula polarizer (from China, about one week for delivery), as advertised. Nice piece of glass for cheap (90$).
fit exactly into the sunshade of the FX1.

Could you post some screen shots of with/without footage for people reading this thread so they can see the difference?

I've been doing a lot of photography / Photoshop lately and this is what will bum me out when I get back into video. "Ohnoes, where is all the data?" heh

Problem is that my 10D produces 6+ megabyte raws, if it ran 24p somehow then that's over eight gig a minute. If a DV tape could spin that fast, it would be full in a minute and a half. Since the XL2 has smaller sensors then the 10D, the numbers wouldn't be all that bad, but it's still a lot of data.
It'd be something else though, huge bandwidth and you wouldn't have to white balance anymore. Plus there already are certain groups that do reverse engineer video cameras and record the CCD data raw instead of compressing it, problem is you need like a data silo or fileserver to store it in the field.

Good points Jeff. I was thinking more along the lines of saving normal DV to tape and RAW data out to an external drive ala FS4 etc.

Colin