Exposure Shift

[Bill Busby]

Originally Posted by Peter Jefferson

that shooting mode wheel is such a waste of space IMO... so much more could have been put there, such as extra custom keys, custom preset dial...

I agree Peter. And regarding more custom keys, I had an ingenious idea (ok, not really) that was an afterthought that was too late for the firmware wishlist. Allowing the menu selector wheel as a "shift" function to add 2 more custom keys. Press inward & hold: custom key 1 = custom key 3, custom key 2 = custom key 4.

If OIS off is ever assigned to a custom key, I'll have to lose one. It's just silly. Two are not enough. Period. :)

Bill

[Bogdan Tyburczy]

Custom key 3 and 4 - very good idea Bill.

It could be done with Custom Keys alone also: press and hold 1 and then press 2 = Custom Key 3. Press and hold 2 and then press 1 = Custom Key 4.

So, with all these great ideas people post on DVInfo.net, all we need is just Canon's cooperation :-)

[Bill Busby]

Exactly. Or maybe a long push on a single button.

But come to think of it, designating the menu select wheel as THE shift function (since depressing it does nothing unless in the menu anyway) all one would have to do is use their thumb to depress it while selecting CK1 or CK2 buttons. It sems to me anyway that it would be easier, but that's just me :)

Bill

[Dino Leone]

Originally Posted by Chris Hurd

We get a lot of new people coming through here who don't have much experience with video, so I make it a point to urge them to shoot in Auto settings at first. The camera does an adequate job in Auto. A new shooter should let the camera take care of those settings, and concentrate instead on the far more important aspects of framing and composition, and developing an eye. Then once they've accomplished that, graduate to the technical part of the photography.

Thanks so much.
I've read this thread twice now, and I still don't understand the "exp lock". And yes, I've read the manual... didn't really get it there either. (Disclosure: I haven't bought the A1 yet - that's why I'm reading everything here and I'm trying to understand as much as possible without actually having played with the camera).
I guess I go back to the manual tonight and study this section once again. Coming from still photography, Alex's first post in this thread was initially a shock to me. Only then did I realize that AV really doesn't seem that useful on a camcorder (as compared to a still SLR camera).

Dino

[Bill Pryor]

Chris...are you saying you can put it in TV mode with Exposure Lock ON, and it 's the same as manual, but you can push a button for auto iris? Which button? (Sorry I don't have the camera with me at the moment.)

This would be handy, because sometimes even with the DSR500 I'll use the auto iris button to let the camera get close, then I'll open up or stop down as needed.

[Bill Busby]

Bill, while in Tv mode & Exposure Lock on, it's the same as Manual. Push the Exposure Lock again to turn it off, then you're in Tv mode again, which is "auto iris" mode.

Bill

[Raymond Toussaint]

Really great would be a push exposure in the manual mode, the same action as push focus. As long as you push, it is auto as soon as you release it is manual again. Not this 'push twice act as a button'. But next to manual... TV mode is the only programme I use.

If you use TV mode, a digital shutter prevents 'overloading the chip' in exceptional cases, not the same as manual. All others can be diminished, like theater and auto and AV.

[Daniel Browning]

Who [in] their right mind is ever going to use Av on a video camera? You can't have the shutter speed ramping up and down in the middle of a shot!

Originally Posted by Chris Hurd

Agreed. It's a holdover from their still camera line. I've always thought that Av mode was pretty much useless, except perhaps for some limited depth-of-field control.

There's another reason to use Av: diffraction. My tooling about with the Cambridge In Color diffraction limit calculator (http://www.cambridgeincolour.com/tut...hotography.htm) indicates that the 1.5 megapixels squeezed into Canon's 1/3" sensor will reach the diffraction limit at just f/4.0. By f/9.5, the softening effect is pronounced.

Because of that, I would rather the camera go from 1/250 to 1/15000 than f/1.6 to f/9.5. For my subjects, 1/250 is just as good as 1/15000. Acceptable changes in motion blur will depend on the audience, subject, and post. 1/250 to 1/48 would be pretty jarring for a scene with a lot of action.

[Robert Garvey]

Originally Posted by Daniel Browning

....indicates that the 1.5 megapixels squeezed into Canon's 1/3" sensor will reach the diffraction limit at just f/4.0. By f/9.5, the softening effect is pronounced.

Wow it sure is soft. I shot a test in bright sun at around F9 and it looked way out of wack!

The manual even mentions it on page 37.

[Raymond Toussaint]

Originally Posted by Daniel Browning

There's another reason to use Av: diffraction. My tooling about with the Cambridge In Color diffraction limit calculator (http://www.cambridgeincolour.com/tut...hotography.htm) indicates that the 1.5 megapixels squeezed into Canon's 1/3" sensor will reach the diffraction limit at just f/4.0. By f/9.5, the softening effect is pronounced.

Because of that, I would rather the camera go from 1/250 to 1/15000 than f/1.6 to f/9.5. For my subjects, 1/250 is just as good as 1/15000. Acceptable changes in motion blur will depend on the audience, subject, and post. 1/250 to 1/48 would be pretty jarring for a scene with a lot of action.

In some situations, the shutter ramp (aperture priority) is no problem, but I prefer to work with (extra) ND to reach the diffraction limit / resolution max with the motion blur and cadense we like from film.

[Chris Hurd]

Originally Posted by Daniel Browning

There's another reason to use Av: diffraction.

That's an excellent point, Daniel. The explanation in your post there provides a good case for Av mode. Thanks a bunch for sharing that!

[Alex Leith]

Originally Posted by Daniel Browning

My tooling about with the Cambridge In Color diffraction limit calculator indicates that the 1.5 megapixels squeezed into Canon's 1/3" sensor will reach the diffraction limit at just f/4.0. By f/9.5, the softening effect is pronounced.

Hmm... Is that true of any 1/3in CCD camera with similar pixel count?

I certainly notice softening by the time it gets beyond about f5.6.

[Piotr Wozniacki]

Originally Posted by Alex Leith

Hmm... Is that true of any 1/3in CCD camera with similar pixel count?

I certainly notice softening by the time it gets beyond about f5.6.

Here is a clip that shows how diffraction can reduce sharpness on the Sony V1; engaging ND filter and opening iris more makes the picture a lot sharper!

http://rapidshare.com/files/18138889...rpness3_ND.m2v

[Daniel Browning]

Originally Posted by Alex Leith

Hmm... Is that true of any 1/3in CCD camera with similar pixel count?

I certainly notice softening by the time it gets beyond about f5.6.

Yes. The only things that matter are focal ratio and pixel size. If the output medium will have larger pixels than the capture medium (e.g. HDV to SD DVD), then the larger of the two is what sets the diffraction limit (assuming the use of a really good resize algorithm.)

For example, Super35 film has very large "pixels". On a work print, f/8 shows no diffraction at all, and even f/11 and f/16 are very sharp. But if it's resized to 480p, it's likely that even f/22 will not show softness.

[Alex Leith]

Thanks for that explanation guys (and the clip Piotr). I had never really understood why softness from diffraction happened at different f-stops on different cameras. And now I do! Hooray!

And at the same time - woah! That's a fairly limited usable range we have!