GL / XM assorted posts, 2003

[Rob Lohman]

That will definitely work, Don. Just as long as you indeed don't
move the camera or else you will need to track. And also don't
have anything pass in fron't of the window or you'll need to
rotoscope as well.

[Lloyd Roseblade]

I am trying to focus purely on a subject and have the background blurry, i.e. reduce the depth of field. Now, I know I can do this if I zoom in on the subject, but I want the same effect in wide-angle. I have tried increasing the shutter-speed (reduce the amount of light through the lens) along with the f-stop setting (to compensate and therefore reduce the depth of field) but just don't seem to be able to lose the focus of the background. Btw, it's a typical daylight scene.

Have I understood the technique correctly (theory anyway)? What am I doing wrong?

Any help, as always, most appreciated.

[Rob Lohman]

Well, this technique is very hard to pull of in DV. You need to have
an f-stop as low as possible, like f1.8. It works best if you zoom
in, but it might work a bit zoomed out. Just make sure your f-stop
is as low as possible. Change anything else to achieve that and
then play around with zooming in and out.

There just isn't another way to do it. If you have access to a
blue or green screen you might shoot your background plate
seperate from your actor and then blur the background before
putting your actor over it. You might also do this through
roto-scoping but that is a very demanding and difficult thing
to do (good).

[Ken Tanaka]

Lloyd,
We have a staggering amount of dept of field topics and posts. We've had months-long discussions on this topic. We have literally exhausted every conceivable aspect of DOF with these cameras. So please do a Search to learn more.

Jeff Donald has also authored a technical article on this subject here.

Bottom line: short of zoom and/or open iris combinations, or silking the background, you're very limited with a 1/4" camera like the GL2. It's probably better to rethink the scene within the limitations of the camera.

[Lloyd Roseblade]

Rob,
Thanks for the info. I didn't realise that the size of the CCD would affect this kind of thing but when you think about it I guess it does kinda make sense.

Ken,
Fair comment. Actually I had done a search but must confess that I didn't read every thread the search returned. Most of the threads I read were related to general DoF and didn't cover the selective focusing I am interested in, or discussed comparison with the PD150, or were where people were being asked to conduct a search ;)

However, I just conducted another search and admit that I did actually manage to locate this same info in another thread. So my apologies.

Funny you should mention that article. It was that article (returned by a search with Google) which got me to DVinfo.net in the first place. In fact I think I make reference to it in my post in the introductions forum. Great article indeed :)

Thanks both for your responses.

[Lloyd Coleman]

I notice on my GL2 that there is a piece of glass on the front that does not appear to be part of the actual lens itself. Is this a built in protective piece of glass? If it gets damaged is it expensive to replace?

I currently have a B&H UV filter on my GL2, but wonder about a couple of issues:

1. Because of the extreme depth of field, anything on the filter shows up in my video. This includes even microscopic pieces of dust if I am shooting toward the sun. I had to put a second filter ring with no glass in it on top of my UV filter to set the lens cap further away from the filter because the Canon lens cap is deep enough that it touches the filter and leaves smudges that show up.

2. Even though the B&W filter is a good quality filter, it is still another piece of glass that may degrade my picture quality.

The glass that comes on the camera is set back far enough that it avoids the lens cap smudge problem and a lot of the dust flair problem. If it is a protective piece that can reasonably be replaced I will probably take my filter off for much of my shooting.

Does anyone have info about this?

Thank you.

[David Woodland]

Hmm.. I never really noticed that peice of glass you are talking about. However, i do have the same UV filter you do and I tend to keep it on most of the time. But of course, all I am currently filming for right now is just my new skate video and I don't see much of a difference when the filter is on.

[David Bohn]

Thanks from a brand new member ! I just got my Gl2 a few days ago and am still trying to figure everything out. I've searched this board for everything I can find about Zebra Stripe settings and experimented on my own a bit; at what point should I begin resetting my exposure to eliminate the stripe pattern because as soon as I get rid of it , my image looks really underexposed. I know from a long experience with using photoshop for my still work , that I can always tweak my image up a bit but it takes forever in rendering time in video work. How much striping is too much and when do you step in to decrease your exposure?

[Ken Tanaka]

There is no pat answer to your question. The answer really depends on your subject and at what point you have your zebra's sensitivity set to (ex: 80%, 85%, 90%, 95%, 100%). Remember that the display is telling you which areas of your image have reached or exceeded the set percentage of overexposure. It's just another tool. Experiment at various settings with the type of shooting you do. Zebra usage for, say, action sports shooting will be different from dramatic shooting. Take notes while you are experimenting so that you can see what works for you. Just remember that 100% bars indicate a complete blow-out.

Also be sure to keep your eye on the general exposure indicator bar at the top of the display. It's telling you the overall level of your exposure.

[Rob Lohman]

See these thread for more information:

http://www.dvinfo.net/conf/showthrea...threadid=13523
http://www.dvinfo.net/conf/showthrea...threadid=11017

[Trig Simon]

When I export from FCP to make 2 hour VHS tape, I also grab the first hour back-up onto mini dv on my GL-2. I then go back and dub off the second hour on another tape later.

Problem is: when the GL-2 tape ends, it flashes "TAPE END" and this goes onto my VHS finished tape, right in the middle of the two hours. How can I stop this from happening.

[Chris Dornack]

IS THERE ANY GOOD VIDEO'S OR BOOKS OUT THERE THAT A PERSON COULD PICK UP THAT SHOW A NEWBIE HOW TO GET THE MOST OUT OF HIS CAMERA.
THANKS IN ADVANCE

[Paul Moore]

You are not going to like this but you need to do it with the tape out of the camera at first. If the camera has no tape in it it will run as an A to D converter till you stop it. Then you can make your DV backup.

[Jeremy Jenewein]

Over the last few weeks I've been putting a heck of a lot of time into finding the "perfect" fisheye lens for my GL2. I wouldn't settle for anything less than 0.3x- which left me with two options. Settle for a... "less than perfect" quality Raynox MX3000/XM3000, or spend $700 on a Century Optics.
I was leaning towards the Raynox, just because I needed that fisheye effect I've missed ever so much (I sold my old camera and 37mm 0.42x fisheye to get some extra GL2 money) when I stumbled upon....

http://www.congiano.com/Photography/PoenixFisheye.htm

The $70 Phoenix 58mm 0.24x full fisheye lens. I thought that for $70, the quality of the lens was going to be complete crap, but much to my suprise, this thing packs a punch! The thing I was most suprised by was the fact that you could zoom in so there was no vignette, without any loss in quality! It almost seems too good to be true...

So I guess I'm asking you all- is there something I'm missing? Is there some sort of catch that little Jeremy is too thickheaded to see? Your comments are very much appreciated...

I'm using XL1 and XM2(GL2) together.
I always find that XL1 color is more warmer than XM2.
I know there is a custom key to adjust the color in XM2.
Can anyone tell me the custom key setting in XM2 to match the color with XL1?

Thanks.