DV Info Net

DV Info Net (https://www.dvinfo.net/forum/)
-   Canon XH Series HDV Camcorders (https://www.dvinfo.net/forum/canon-xh-series-hdv-camcorders/)
-   -   What am I doing wrong? (https://www.dvinfo.net/forum/canon-xh-series-hdv-camcorders/181508-what-am-i-doing-wrong.html)

Keegan Quiroz April 10th, 2009 09:22 AM

What am I doing wrong?
 
I dont get it; I film in 1080, I use HD tape, I encode in 720 for the internet. But still it looks really bad! A lot of the shots were filmed with a crazy high shutter speed so thats why theyre so dark btw. Also, this is a canon xh a1 obviously. I am new to this forum so this looked like to right place to post this.im shooting at 60i but i accidently shot some clips in 24p haha.The slow motion didnt work out as I expected but next time im going to use optical flow remapping. I actually just turned off AGC right now and set it to -3 db. I made that video with Premiere pro cs3 but had to capture the footage with imovie, but now im using cs4 and final cut studio 2 and shake. The footage just looks really blurry and not as crisp as it could. EDIT:Oh and a lot of that was shot at 1/15000 shutter speed

Michael Hutson April 10th, 2009 11:18 AM

If you were using auto focus and auto gain....that may be your issue. the sweet spot for the xha1 is 4.0-5.0 f-stop. I got a feeling, your gain was out the roof.

hope this helps.

Keegan Quiroz April 10th, 2009 11:22 AM

Yeah I was, I just changed AGC off and set it to -3db. sorry if this sounds dumb but whats 4.0-5.0 f-stop? Is this the focus? Thanks

Bradley Ouellette April 10th, 2009 12:15 PM

If you encoded for the internet, just double check your bitrate on the video and audio. When I first did mine, it looked horrible till I realized it was too low...

Keegan Quiroz April 10th, 2009 12:43 PM

Quote:

Originally Posted by Bradley Ouellette (Post 1075718)
If you encoded for the internet, just double check your bitrate on the video and audio. When I first did mine, it looked horrible till I realized it was too low...

when i encoded it it was around 6000 kbits per second

Keegan Quiroz April 10th, 2009 01:23 PM

Huh, I just realized I have been using an adapter thats really dark, Im not really sure what it does because I got it for free but I have all these

Merkury Innovations

The one I was using says : MERKURY OPTICS JAPAN 72MM F-DL

and the others say

MERKURY OPTICS JAPAN 72MM PL
and
MERKURY OPTICS JAPAN 72MM UV

what do these do? should I be even using one?
thanks

Nick Gordon April 11th, 2009 01:02 AM

You have a set of 3 filters.

The one marked UL is an ultraviolet filter - it filters out UV, which can improve contrast
The one marked DL is probably a daylight filter, which is very similar to the UV filter (slightly different spectrum filtered)
The PL one is a polarising filter, which is used to cut down on reflections from windows, water and so on. The PL filter will darken the image.

On a camcorder, the UV filter can help to protect the lens from scratches - many people (including me) leave on on most of the time.

I suggest you shoot some test footage without the DL filter to see whether it makes a difference. If it is a daylight filter, it shouldn't darken the image.

By the way, having looked at the Merkury site, I'm not impressed. They should at least spec what the filters do.

Nick Gordon April 11th, 2009 01:26 AM

Quote:

Originally Posted by Keegan Quiroz (Post 1075487)
Yeah I was, I just changed AGC off and set it to -3db. sorry if this sounds dumb but whats 4.0-5.0 f-stop? Is this the focus? Thanks

It's the iris (aperture for still cameras). The amount of light that gets through a camera/camcorder lens depends on two things: how long the shutter is open (longer opening lets in more light) and how wide the aperture through which the light comes in is. Cameras have an iris which cane be opened and closed to make the aperture bigger or smaller.

With a big aperture, you can use a faster shutter (open for a shorter time) to reduce blurring (for example). With a smaller aperture, more of the image will be in focus, but the shutter has to be open longer to let enough light in to get a good image).

Iris/aperture size is expressed as a proportion of the focal length of the lens. So f4.0 means the diameter of the iris is one-quarter the focal length of the lens. Because it's a proportion, small numbers mean bigger openings (if the lens has focal length of 50mm, f4 is 12.5mm, f8 is 6.25mm, for example).

The Canon will guess at how to set shutter and iris for you, if you have exposure set to auto. You can set either shutter or iris manually, if you want to, but then you need to understand how to manage shutter and iris together. What many people do is set the shutter to a speed related to the frame rate (e.g. if you're using 60i, set the shutter to 120) and let the camera choose iris settings.

The other factor in determining the image is gain. Gain is nothing to with the lens or light - it's an electronic way of lightening the image in the camera sensor. If the scene is too dark for you to be able to get a wide enough iris/slow enough shutter to get a good image, gain can help, but the price is that it degrades the quality of the image. That's why everyone advises you to switch auto-gain off. If you leave it on, the camera will 'helpfully' adjust it to allow you to keep a good shutter/iris combination, but it won't care what that does to the image.

Hope that's not too long-winded. If you can get to understand some of these (slightly confusing) concepts, it'll make you more confident. There are some good primers around the web. Google 'camcorder aperture' to get started

Keegan Quiroz April 11th, 2009 08:06 AM

Yeah that was helpful, thanks.

Keegan Quiroz April 27th, 2009 05:48 PM

huh
 
yeah i just shot some stuff doing all the things i was told to do but it still looks kind of grainy along with a few other things check it out. this is also with some color presets and post color correction and a vignette filter(i just wanted to see how it would look haha). thanks again
oh and this is with 24p if that matters at all

http://www.vimeo.com/4364924

Ken Wozniak April 28th, 2009 02:54 PM

You say your original footage looks grainy? The stuff on Vimeo is hard to analyze since it has been compressed for the web. Would it be possible to post a short clip in 1080i in the standard m2t format?

Try shooting without any filters or presets. Keep the automatic gain off. Do NOT shoot in "green box" mode. Shoot in "A" if you must, but AVOID THE GREEN BOX. If you shoot 24F, keep your shutter at 1/48. Not for high-speed stuff, though. For that, use 60i.

Keegan, based on your questions regarding terminology, you appear to be new to videography, and photography in general. Starting with an XH-A1 is pretty brave! Jump right into the deep end, eh? If my assumptions about your experience level are incorrect, I sincerely apologize. It's just me opening my mouth and inserting my foot...like usual.

I hope we can help you get your video problem figured out. The people here on dvinfo are real helpful, so you're asking the questions at the right place.

Keegan Quiroz April 30th, 2009 10:33 AM

Quote:

Originally Posted by Ken Wozniak (Post 1134614)
You say your original footage looks grainy? The stuff on Vimeo is hard to analyze since it has been compressed for the web. Would it be possible to post a short clip in 1080i in the standard m2t format?

Try shooting without any filters or presets. Keep the automatic gain off. Do NOT shoot in "green box" mode. Shoot in "A" if you must, but AVOID THE GREEN BOX. If you shoot 24F, keep your shutter at 1/48. Not for high-speed stuff, though. For that, use 60i.

Keegan, based on your questions regarding terminology, you appear to be new to videography, and photography in general. Starting with an XH-A1 is pretty brave! Jump right into the deep end, eh? If my assumptions about your experience level are incorrect, I sincerely apologize. It's just me opening my mouth and inserting my foot...like usual.

I hope we can help you get your video problem figured out. The people here on dvinfo are real helpful, so you're asking the questions at the right place.

Yeah I am pretty new to this haha. So I shot some more today at a pretty dark place but it turned out really well. I was shooting in 30F, -3db gain, 1/120, 1/6 on camera ND filter, 2.4 and 2.6 iris I think it's called, and I didnt set the white balance totally white because to be honest I kind of made everything looked all washed out. But my footage turned out really good with hardly any grain so I'm happy. In the vimeo movie above I was shooting in 6db gain and a really small iris (I think it's called). So maybe that was my problem. Oh, and that you guys for helping me learn this stuff!


All times are GMT -6. The time now is 10:49 PM.

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