lack of defintition in wide angle with dslr?

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I'm really hoping someone on here can help me with this problem. I'm using a canon 600d to shoot video. At times it can shoot great HD but I cannot get it to shoot wide angle shots as I would like them to look. The wide angle "landscape" type shots always lack definition.
Here is what typicaly happens : Using the lens at 18mm I film a wide angle shot with trees in the distance, The leaves on the trees at all distance are blurred and shapeless even if the camera is still on a tripod.
When I zoom in on something or a subject fills the frame this doesn't happen at all. I have tried hundreds of different approaches including using a 50mm prime. the result was the same.
I have used different shutter speeds from 30 to super fast. I mainly use a natural setting with minimal or no sharpening but I have tried it all ways. I have also tried post sharpening. It helps but not much. I try to never use ISO over 400.
I realise that these softer shots sometimes look great , filmic and draw the eye to the colour rather than the shapes but what if you want definition. ?
Here is a video that exhibits some of the problem. The shots of the wild boar are good (well sharp anyway :) ) and thats the main thing but check out
1 minute 8 seconds to 1 minute 20.
http://www.youtube.com/watch?v=LNlTMyLFA9w
It kind of works because its nice autumn colours but you can even tell what types of trees they are by the leaves. The clips of wild boar and birds are using a 70-300 lens which is in a different league I know but Like I say trees in the background didn't look any better with the 50mm prime. I have also experimented with aperture size as obviously For this type of shot I might want a large depth of field.. Any advice greatly appreciated.
ps. Its one area where the camcorder I used to use far exceeds the 600d which makes me think it might be a due to the rolling shutter of the dslr... Thats my hunch but any input greatly appreciated. :)
 
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A camcorder use a considerably shorter focal length so will have a much greater DOF than a DSLR. What aperture are you using, are you really that close to use an 18mm lens, I would have thought longer, so DOF is not going to be adequate to get something in foreground or perhaps middle and the background with reasonable sharpness, particularly at widish apertures which you are probably having to use in a forest environment.
 
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It's not so much the focal length but more the sensor size. Bigger sensor = shallower depth of field.
 
Fairly simple answer to your question: Lack of effective resolution.

While you may be shooting at 1080p you are infact not actually recording any image information at 1080p. I think the effective resolution of most of the canon DSLRs is more akin to 1280x720 perhaps even less. The camera upscales the image to 1080p afterwards. This upscaling is the cause of the soft images since the camera is having to make up pixels that aren't there.

Highly detailed landscapes have always been a weak point for DSLRs. Either go photo mode and use time lapses or use a camcorder like you are now.
 
Fairly simple answer to your question: Lack of effective resolution.

While you may be shooting at 1080p you are infact not actually recording any image information at 1080p. I think the effective resolution of most of the canon DSLRs is more akin to 1280x720 perhaps even less. The camera upscales the image to 1080p afterwards. This upscaling is the cause of the soft images since the camera is having to make up pixels that aren't there.

Highly detailed landscapes have always been a weak point for DSLRs. Either go photo mode and use time lapses or use a camcorder like you are now.

It's the opposite.

HD is about 2 megapixels. DSLRs are about 15. You need to throw a lot of high frequency data away when you downscale to HD or there will be a lot of aliasing and ringing on edges.
 
Fairly simple answer to your question: Lack of effective resolution.

While you may be shooting at 1080p you are infact not actually recording any image information at 1080p. I think the effective resolution of most of the canon DSLRs is more akin to 1280x720 perhaps even less. The camera upscales the image to 1080p afterwards. This upscaling is the cause of the soft images since the camera is having to make up pixels that aren't there.

Highly detailed landscapes have always been a weak point for DSLRs. Either go photo mode and use time lapses or use a camcorder like you are now.

That's interesting. Didn't know that!

So if this is correct, in theory - shooting 720p will yield better results???
 
That's interesting. Didn't know that!

So if this is correct, in theory - shooting 720p will yield better results???

Nope

As I said, the problem is caused by the down conversion filter from 20+ megapixels to approx 2 for 1080p or 0.93 for 720p. They're 2 different filters - so you can't assume 720p is better.

As a representative example, looking at a D4 the EBU managed to measure 1355x762 for 1920x1080p and 1030x580 for 1280x720p mode. See: http://tech.ebu.ch/webdav/site/tech/shared/tech/tech3335_s01.pdf

Real video cameras use correct resolution sensors and don't filter.
 
Nope

As I said, the problem is caused by the down conversion filter from 20+ megapixels to approx 2 for 1080p or 0.93 for 720p. They're 2 different filters - so you can't assume 720p is better.

As a representative example, looking at a D4 the EBU managed to measure 1355x762 for 1920x1080p and 1030x580 for 1280x720p mode. See: http://tech.ebu.ch/webdav/site/tech/shared/tech/tech3335_s01.pdf

Real video cameras use correct resolution sensors and don't filter.

No wonder I've always thought the quality wasn't THAT good...

Thanks for the info!
 
st599 said:
Nope

As I said, the problem is caused by the down conversion filter from 20+ megapixels to approx 2 for 1080p or 0.93 for 720p. They're 2 different filters - so you can't assume 720p is better.

As a representative example, looking at a D4 the EBU managed to measure 1355x762 for 1920x1080p and 1030x580 for 1280x720p mode. See: http://tech.ebu.ch/webdav/site/tech/shared/tech/tech3335_s01.pdf

Real video cameras use correct resolution sensors and don't filter.

That's strange since I find the quality of video coming off the d4 in 2.7x crop mode to be very good indeed.
 
I think the effective video resolution of Canon DSLR's is a little less than 720p actually. That's what happens when you try to record 1920x1080 (which quite rightly has been pointed out as being around 2 megapixels) from an 18 megapixel sensor.

In comparison, the Red Epic shoots 5K video with a 13.8 megapixel sensor. 5120 x 2700 = 13.8mp. In order to shoot lower resolutions such as 2K, 1080p etc it actually crops the image so it only uses as much of the sensor as it needs in order to keep the highest image quality. This poses a problem because if you want to shoot in 1080p with the Epic, you end up getting a massive amount of crop (something like 7x) meaning you need to use ridiculously wide lenses to achieve the same field of view.
 
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