The Canon 7D is Actually Closer to 35mm Film Size that the 5D
 

If I am looking at this chart properly, it appears to me that the APC imager is actually closer to the 35mm film "imager" than the full frame 35mm imager in the the 5D.

http://upload.wikimedia.org/wikipedi...inside.svg.png

Remember, the 35m motion picture film image width is approximately the same as the height of the full frame chip.

By flipping the APC imager size on the chard to match the height of the 35mm frame, we see that width is very close to the full frame height. Thus the APC imager would likely give us closer approximation of 35mm motion picture film camera depth of field than that of the 5D.

Any one disagree with that ?

You are exactly right, Chris.

I like the idea that the 5D2 shoots video that looks like moving magazine spreads.

S35, or crop sensors can give results like typical Hollywood films.

16mm or 2/3" is like broadcast TV, documentaries, or the indie films before digital.

Of course, one can always stop down a lens on a FF cam and get the look of a smaller sensor. Small sensors lack that flexibility, as well as the sensitivity.

One nice thing about a crop sensor is that you can use moderate FF lenses with good results. Open your non-L lens all the way, and our 5D2 will show some falloff and softness in the corners. Put the same lens on a crop sensor cam, and the corners will be pretty solid at the same aperture.

Of course, having a FF cam for photos is pretty sweet. I'm hoping for new firmware, in which case I will definitely keep the 5D2.

The problem with smaller chips like APC is in getting wide enough lenses. A 24mm lens on the 5DMKII is...a 35mm lens, just like on a film still camera. On an APC size it goes up by 1.6 and is a little longer than a 35mm lens.

I thought the APC size was very close to the 2/3" chip size or to 16mm size. I wish the chart had those laid out.

To get that shallow depth of field lots of people seem to want, you're going to have to track down some very fast lenses. None of the zooms open up past f2.8 at full wide angle and most stop down more at longer lengths.

Yeah, I have a Nikon 35mm F2 Prime that I figure would make a great normal for the camera. I also have a 24mm that would be my widest-- comparable to the 35 for angle on the APC. Now, how to go wider. Fisheye ?

I read someplace there's a Nikon to Canon adapter so you can use Nikkor lenses on Canons. I have a bunch of ancient pre-AI Nikkors, which won't work on new Nikons without a funky adaptation. But presumably they would work with an adapter on Canon. Obviously only manual focus and iris would work, but that would be fine with me.

According to this article Charge-coupled device - Wikipedia, the free encyclopedia the APC size chip is quite a bit bigger than a 2/3" chip. I thought they were closer together. But the article gives the width as 25mm, height as 16; I think Canon says 22mm and 14mm. Does anybody know if these figures are right? (Scroll down to the chart in the wiki article). Of course, when we crop down to a 16:9 aspect ratio from the 3:2, we're going to lose quite a bit of that 14mm height, which means, in effect, using a chip that's smaller than the APC size.

One advantage is that we'll get to use the 17-55mm f/2.8 IS, which is by many accounts an excellent wide-to-normal f/2.8 zoom.

The 17mm comes out about 28mm and the 55 will be a little over 80mm, so that's a nice range but not really wide. I guess one of those .6x wide angle adapters might work on a lens like that; if so that would be good.

There is also the EF-S 10-22mm, which (although not particularly fast) does come out to an equivalent 16-35mm.

I am various ages of Nikon lenses I have been using almost exclusively. They work fine with the 5D, and I would hope same adapters would work with 7D. But, Canon could have done something to prevent that...

As far as angle of view, I think the horizontal width is the determing factor in comparing the lens angle of view.

Now that I think about it, I think you're correct about the horizontal dimension. Back in my DVCAM days I had a DSR500 with 16:9 chips. When I had to shoot 4:3, it cropped in from the sides, and my lens was effectively a longer focal length.

The chip on this camera is about the same size as a Red 1 and/or 35mm "movie" camera. That's why it is perfect for filmaking. The 5Dll's FF sensor is more like Vista vision and perfect for stills.

Check chart here:

http://en.wikipedia.org/wiki/File:SensorSizes.svg

or better yet here:

http://www.google.com/imgres?imgurl=...num=5&ct=image

I can attest that the 17-55 f/2.8 IS is an outstanding lens. I have one for my 50D and look forward to using it on a 7D. It is L lens quality, very sharp, with image stabilization and it will focus quite close, nearly macro.

The Tokina 11-16mm f2.8 should fit the bill of a nice fast wide angle zoom for the 7D. I have the Nikon fit one and it is pretty great. Ultra fast wide angle primes are harder to accomplish, the Olympus 21mm f2 or Sigma 20mm f1.8 are the only options that spring to mind. Other than that Cine primes will be the other choice, but then thats megabucks.

Dan

Confirmed that APC chip is quite close to 35mm cine. I have been using an APC camera for years on scouts for film shoots (and more recently, full-size sensor HD shoots) and the focal lengths are very similar.

For what it's worth, every AC I know who works with the 5DMKII has had a brutal time maintaining "sharps" with that format. Certainly it is much more delicate than the little viewfinder on the back will confirm. Shallow focus is only worth it if one can actually keep the subject in focus...! The APC sensor delivers a nice compromise, if even that.

Charles, absolutely agree about the "sharps" thing. APS-C should be much better than 5DmkII full frame for a given angle of view. That said for low light shooting the FF still has the advantage due to the lack of APS-C fast aperture wide angles.

Dan