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what shoots better video, the 7d or 5d mark II

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Thanks for the explanation Wagsy. The original poster made this sound like a problem with the 7D, but you suggest that he is just talking about CMOS rolling shutter (I've never heard it described as "Jello" before), right? If so, then the effect should be no different from what I see with my Sony A1U, right?

 

I'm really looking forward to your report.

 

--Mark

 

Well, the problem with ViDSLR is that the sensor isn't a dedicated video sensor. So the sampling is more akin to cellphone wobble than video camera. With the Dual Digic IV processors, the 1D4 seems to have it under better control than the 7D, which is better than the 5D2. My own comparisons seem to jibe with everyone else's in that the 5D2 offers the cleanest video in higher ISO.

One important factor not to forget is the lens. From micro-contrast to resolving power, the better the lens the greater video output.

All this was done last year but I spent a few hours testing L lenses and others like Sigma, Nikon via an adapter and Zeiss. The Zeiss ZE are just so much sharper for video. Canon EF L lenses aren't as sharp and are a bit more saturated. As a still lens, it's got great but for video, depending on your output, sharpness is your priority, since it gives post the best possibility in an 8bit, 4:2:0 compressed codec. I mention these as criteria for filmout guys. The look is obviously a personal thing. But what translate well are the differences in the Nikon and Canon lenses . I like the colors from the Canon but Nikon contrast and sharpness is better than Canon, especially in the WA lens.

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Yes Jello, rolling shutter, same thing.

I shot the props on the mine plane last swing with my Ipod nano and its got it really bad, blades where bending kind of thing.

Mark, I have a Sony A1 too but the 7D is worse, but shoot it correctly and you get stunning footage. :(

I wanted to get my hands on a Tokina 11-16 mm but hard to get so will shoot the house with the 18-135mm and I will post it up.

 

Damien I don't use IE only firefox and cannot see your video.

So I fired up IE and there is was. watching now......

That video player may need updating or something you got on your site there.

 

Professor Drew..... is there anything you don't know :lol:

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If you remember I was in on the wave of enthusiasm once the ViDSLR were announced. It is a game changer and about 20-30% of the sales are from cinematographers, which is why Canon broke down to add 24/25fps. To get good stuff, the trick is to get closer to the action. The resolution is crap so if you shoot wide landscapes, the codec is challenged. Get in closer with a sharp lens and the resolution flaws are well hidden. That's why cinematographers love the shallow DOF. It doesn't translate well in with deep DOF shots but the 3D element of blurring out the background looks sexy. If you can get the focus down :(

It's an amazing tool with many pitfalls. A flawed hot girlfriend with personality issues is my friend's analogy. :lol:

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Damien I don't use IE only firefox and cannot see your video.

So I fired up IE and there is was. watching now......

That video player may need updating or something you got on your site there.

 

All fixed. Looks like Firefox 3.5 had an issue with the javascript library I was using. A direct download in 720p h.264 format is also available at http://blip.tv/file/get/Dsiviero-SSBirchgr...kFeb2010894.mp4

 

I'd also agree with the discussion points here that say the DSLRs aren't as easy to use as camcorders. I found the 7D to be very easy to use underwater in WA shooting as DOF is massive, but difficult to use with a normal type lens (specifically a 28mm f/1.8). Trying to keep focus on a subject was difficult and the feedback through the LCD screen doesn't really tell you where the focal plane is. I know you can enlarge the screen but then that looses framing.

Edited by betti154

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If you remember I was in on the wave of enthusiasm once the ViDSLR were announced. It is a game changer and about 20-30% of the sales are from cinematographers, which is why Canon broke down to add 24/25fps. To get good stuff, the trick is to get closer to the action. The resolution is crap so if you shoot wide landscapes, the codec is challenged. Get in closer with a sharp lens and the resolution flaws are well hidden. That's why cinematographers love the shallow DOF. It doesn't translate well in with deep DOF shots but the 3D element of blurring out the background looks sexy. If you can get the focus down :(

It's an amazing tool with many pitfalls. A flawed hot girlfriend with personality issues is my friend's analogy. :lol:

 

Drew,

 

What do you mean by "the resolution is crap"? It is 1920x1080 (which is better than HDV). Are you referring to the sampling used on the 7D to go from the 17.9 MPixel sensor resolution down to the 2 MPixel resolution of HD, the H264 compression, or compared to film?

 

I am *strictly* an amateur here, so I have no intension of ever trying to sell my shots. I've been shooting video (first DV, and now HDV with a Sony A1U) for about 10 years. A couple of trips ago I picked up a Canon G9 and an Ikelite housing to take stills. I am very happy with the quality of the G9 shots I've been taking (the camera is better than I am). However, now I have to drag two rigs with me on my dive vacation, and I have to choose which rig to take down with me on a dive (video or still). Finally, I'm not at all happy with the low light capabilities of the A1U nor am I happy with the manual white balance on the A1U (it doesn't work below about 25 feet).

 

What I want is one camera that I can take decent HD video on, and take good still photos on the same dive. So, what I'm asking is are the concerns about the 7D related to use for professional photos and video, or is it just not ready for primetime?

 

Thanks,

 

--Mark

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I'd also agree with the discussion points here that say the DSLRs aren't as easy to use as camcorders. I found the 7D to be very easy to use underwater in WA shooting as DOF is massive, but difficult to use with a normal type lens (specifically a 28mm f/1.8). Trying to keep focus on a subject was difficult and the feedback through the LCD screen doesn't really tell you where the focal plane is. I know you can enlarge the screen but then that looses framing.

 

According to DOF master (www.dofmaster.com – a great site BTW), if you shoot a subject 5 feet away with a 28mm lens at f/1.8 (using the 7D) the depth of field (the distance between the closest that an object is in focus and the farthest it is in focus) is just 0.65 feet (20 cm). If you shoot at a subject distance of 10 feet, the depth of field is 2.65 feet (81 cm), and if you shoot at a subject distance of 15 feet, the depth of field is 6.12 feet (1.9 meters). This is primarily a limitation of the fundamentals of optics (using a 28mm focal distance lens with an aperture of f/1.8; the 7D has very little to do with it).

 

If, on the other hand, you used the Sigma 17-70 DC Macro HSM lens, and shoot at 28mm with an aperture of f/4.5, then you get the following depth of fields:

 

5 feet subject distance: 1.67 feet (51 cm) DOF

10 feet subject distance: 7.37 feet (2.25 meters) DOF

15 feet subject distance: 19.6 feet (6 meters) DOF

 

The only difference here is going from an aperture of f/1.8 to an aperture of f/4.5

 

Here is another example (for those of you who are interested): using a Tokina 10-17 at 15mm and an aperture of f/3.6 (the calculator lets me choose f/3.4 or f/3.6) you get the following depth of field:

 

5 feet subject distance: 5.72 feet

10 feet subject distance: 109.3 feet (effectively infinite under water)

15 feet subject distance: infinite

 

Note: the DOF is not symmetric in front of and behind the subject. So, for the above example, the close and far in-focus distances are:

 

5 feet subject distance: close focus 3.44 feet (1.05 m); far focus 9.16 feet (2.8 m)

10 feet subject distance: close focus 5.23 feet (1.6 m); far focus 114.6 feet (35 m)

15 feet subject distance: close focus 6.33 feet (1.9 m); far focus infinite

 

Note: I have not taken into account any effects of refraction due to water or using a flat vs. dome port (I’m not sure how to do that yet). If I figure out how to take this into account, I’ll update this post.

 

The interesting part of all of this is that the depth of field is a factor of the lens, not the camera (it is the camera a little bit in the size of each pixel). The fact that you don’t have DOF problems with a video camera is because you can't put an f/1.8 lens on a video camera. On the other hand, with a wide lens like an f/1.8, it sure would help to have continuous auto-focus! This IMHO is where things can improve with DSLR video. You want the ability to use a nice f/1.8 lens, but you need autofocus to make it easy to keep the subject in focus.

 

--Mark

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What do you mean by "the resolution is crap"? It is 1920x1080 (which is better than HDV). Are you referring to the sampling used on the 7D to go from the 17.9 MPixel sensor resolution down to the 2 MPixel resolution of HD, the H264 compression, or compared to film?

 

I mean the actual resolution of the clip captured by the lens. Which is around 6-700 lines, maybe a bit better if you use good glass like the Zeiss ZE. Just because the result is 1080p doesn't mean it is resolving at 1080. The aliasing artifacts from the sampling causes all sorts of moire and other artifacts, killing resolution.

Obviously many people embrace the short comings and use the camera's strengths, which is the shallow DOF and low light ability.

 

And about DOF charts, you should use it as a guide but never as an absolute as lenses aren't always perfectly at the designated focal length, nor are the apertures always pin on accurate. Always check the focus visually.

It's also possible to rack focus using gears. Shooting with L primes and Zeiss ZE give the best resolution. Zooms tend to be softer. Then learn to understand the focus ring of the particular lens and follow focus manually. It's a lot of practice but it is an awesome tool once you get the hang of it. AF can be fooled,

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It's an amazing tool with many pitfalls. A flawed hot girlfriend with personality issues is my friend's analogy. :)

 

I like it - a perfect summary! ;)

 

Just for the record our 7D is about to be sent back to Canon for the second time. First time it was horizontal black lines across the image, this time it is what I can only describe as blobs (guy in the shop said it was sensor burn, but he could have been wrong). I've no idea if this is common or not and I've not had the time to research it, but twice seems a bit too much of a coincidence to me...

 

Cheers, Simon

Edited by SimonSpear

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With the dual digic IV processors, the 7D cooks a lot faster than the 5D2 or 1D4 in video mode. In my outdoor tests, the temperature warning came on more than a few times. Maybe Canon will have to make a white or silver 7D Mark II :)

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You do realise that Nikon will be increasing the pixel count on their new cameras? That's what they've said. How much I don't know, but it gives the lie to those people who have been saying that Nikon's policy of keeping pixel counts relatively low is a fundamental policy decision.

 

I agree about the 1D series - I've never understood WHY. The 1Ds is another matter.

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The interesting part of all of this is that the depth of field is a factor of the lens, not the camera.

 

--Mark

 

 

DOF is a function of f-stop and reproduction ratio. Thus a smaller sensor will have a higher DOF because of the lower reproduction needed to fill the frame.

 

Example: if the subject/scene is 35mm wide, a full frame camera will require 1:1 reproduction ratio to fill the frame. A theoretical sensor that is 12mm wide could fill the frame with a 1:3 reproduction ratio.

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DOF is a function of f-stop and reproduction ratio. Thus a smaller sensor will have a higher DOF because of the lower reproduction needed to fill the frame.

 

Example: if the subject/scene is 35mm wide, a full frame camera will require 1:1 reproduction ratio to fill the frame. A theoretical sensor that is 12mm wide could fill the frame with a 1:3 reproduction ratio.

 

Yeah, you can look at it that way if you want to. You can either apply the crop factor to the focal length of the lens, or to the DOF calculation. If you apply the same lens to a full frame sensor camera and to a 1.6X crop factor camera, and set that lens to the same f-stop and same focal length, then you will have the same depth of field. However, you will not have the same angle of view. If you take the same lens (let's suppose it is a zoom lens) and zoom it on the two cameras so that it has the same angle of view for both pictures, then the camera with the smaller sensor will be more zoomed out (shorter focal length), and hence will have a larger DOF. So, if you want to look at it from the point of taking pictures that are the same perceived size, then the camera with the larger crop factor will have more depth of field. But, you have to realize that you are changing the setting on the (zoom) lens to achieve the same perceived image size.

 

So, in short, what you probably care about is what the DOF is for a given image size. Since the different camera crop factors require you to change the zoom on the lens in order to get the desired image size, the choice of camera *does* affect the DOF.

 

I have also glossed over the circle of confusion, which *is* a factor of the camera.

 

Sorry if I created any confusion.

 

--Mark

Edited by DrMark

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I would go for the 7D for pure macro. With the slightly smaller sensor you will get a deeper depth of field, which is always the problem with macro. The DOF is still much shallower than with HDV cameras. I hope to test mine out soon with the 60mm macro lens.

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Thanks Ferg, that's interesting. I wonder how the magnification/DOF of a 7D with 60mm macro lens would compare with my Z1 plus Century +3.5 diopter.

 

Really tempted by a dabble with the cheaper Canon 550d, topside at first. Similar sensor/video performance to the 7d (apparently) but in a light, plastic body. Plus there is a Nauticam housing on the way for it. Anyone know if the fact that it only has one digic 4 processor (compared to the 7d's pair of them) would be an issue for u/w video?

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I've heard the 550D is as good as the 7D for video, a colleague has just purchased 4 and we are using them on an up and coming project with a couple of 5D's so it will be interesting to see how they go.

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Jonny, what housings is your colleague going to use, or are they for topside use? If so, what lenses?

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Jonny, what housings is your colleague going to use, or are they for topside use? If so, what lenses?

 

 

I wish it was for underwater, all topside and he has a stack of Canon lenses that we use but mainly the 24-70 2.8 and the 50mm 1.2. For underwater I reckon the 14mm would be awesome.

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