Tricks of controlling 5D mark II + EF lenses exposure manually
 

I fonund some tricks to select the ISO, shutter speed, and aperture manually.

1. Setting to M mode. Use your hand to cover the lens, controlling the amount of light income. You would see the ISO going up and the aperture, shutter going down.

2. Remove your hand in bright light, you would see the ISO going down and the shutter going up quickly within 1 second. Press the AE lock "*" immediately. Because of the AE adjustment order is ISO, followed by shutter speed, followed by aperture. If you can press the AE lock within 1 second, you can lock the changing ISO, shutter, and aperture in certain values.

3. If you can seize the timing of pressing AE lock, you may lock the exposure values you want. Combine with the control of light income, you can get almost every exposure values you want. Just like controlling the exposure manually, althouth it may be troublesome.

This method can reserve all functions of 5D mark II, including contrast-based AF and shooting pictures during recording.

I am from Taiwan and my English writting ability is not good. I have written detailed description in Chinese. I hope someone can translate it and post here.

The full article:
http://www.hd.club.tw/thread-17068-1-1.html

Best Reguards.

Charles Wu

Hello Charles,

I think 1/30 shutter is the slowest possible speed when shooting video.

At 30 fps, if the shutter is open 100% of the time (360 degrees), the result is 1/30 seconds.

This assumes that the sensor is reset to 0 after each frame.

You can simulate longer than 1/30 in post with motion blur (blending frames.)

I've seen it dip down to 1/20th....

I wonder if this is real though, unless the camera is dropping frames. =8-o

1) The shutter opens and the sensor starts collecting light.
2) 1/30th of a second later, the information is read from the sensor
3) The sensor is reset.
4) Go back to step 1 and repeat.

You can fake a longer shutter by not resetting all the way to black in step 3 above, but that's not really a 1/20th shutter. It's a frame blend, and you can do that with much better control in post.

The bottom line is that you can't really expose longer than your frame to frame interval. 1/30th on a 30fps camera is already 360 degrees, and that's as far as it goes.

That the screen says something longer than 1/30th is another story. :)

I haven't seen any value I want. On fast ef lenses, I typically see: wide open, f2, f 5.6, fully stopped down.
What are you guys seeing?

Well, we are almost certainly seeing shutter speeds much higher than specified.

But I do think the shutter speed momentarily reported may be some sort of intermediate value before the actual value is set. Clearly the code setting movie auto exposure is not refined.

Is there any other way to see exposure value other than for several seconds after AE lock?

I'm sorry to say I'm skeptical. I believe you are seeing the camera value that are changed when you press record. The only way I've found to set exposure values is with the camera actually recording.

According to Canon, shutter speed during video mode is limited to a range between 1/30 and 1/125.

Yes, I really see the blending frames. I konw that is simulate effect. But it can incresae the exposure.

Yes, you are right. I just mean the camera value when I recording. I'm sorry for the misunderstanding.

I think I should delete the item 4. "I found in M mode, the lowest shutter speed is 0.8 sec. In Tv and Av mode, the lowest shutter speed is 1/5 sec. Quite different from previous articles." to prevent out of focus.

Item 1.~3. is uesful and proven by other 5D2 uses in Hong Kong and China who read my detailed prescriptions of Chinese version. I suggest 5D2 owners can try it.

Thanks for all replies and corrections. And sorry for the limitation of my English expression.

I'm satisfied that shutter speeds go much higher.

Anyone able to keep exposure values when doing AF? I find this resets exposure.

I think this is because the camera's AF system need large aperture to help focus.

If you lock the camera with the largest aperture, it may not change the exposure values.

Thanks, I'll keep working on it.
Maybe I'll need to learn Mandarin to properly use my camera :)

Anyone for translation? For resume?

Merci

One thing I've noted is that even if you lock exposure, if you change the focal length of the lens during the recording the shutter speed and iso will change. The lens unlock technique should be able to overcome this, but the zoom ring tends to be so tight that you either end up completely unscrewing the lens or snapping it back on.

There is the option of taping the contacts after setting aperture. Or using a non-canon zoom.

This is incorrect.
While the 'normal' phase detection AF operates at max aperture, the camera's contrast detection AF only needs -- contrast. It doesn't necessarily need a large aperture if there is enough contrast.

If you have a lens with max aperture of 2.8, and hit the AF button while shooting at 5.6 (regardless of whether the exposure is locked or not), it will stay at 5.6 if there's enough contrast, or by brightening the image by upping the ISO. It will only change to 2.8 if it's still too dark.

This is also incorrect.
If you lock the camera at the largest exposure, and there is not enough contrast (too dark), it will still brighten the image by upping the ISO.

The AF button is useful and accurate for pre-focusing before shooting.
But not useful while shooting.

Do you mean it keeps your previous setting (aperture) in any case?

Does it keep the aperture? And the shutter speed?

Does it change the exposure values? In this case, which ones?

Merci.

Another thing I tested is that if you lock the aperture at max aperture and there's not enough contrast because the area within the AF focus square is too bright (instead of being too dark), it will stop down the lens to increase contrast.

If you have exposure lock on, then it will return to the locked aperture after the AF locks in.
For example, if the exposure is locked at 5.6 and it's too bright, it will stop down to a smaller aperture (ex 16) and change it back to 5.6.
If it's too dark, it will open it up to max aperture (ex 2.8) and return to 5.6.
If there's enough contrast, then it will stay at 5.6 while the AF is working and after.

The info display (aperture/speed/ISO) does not update while the AF working.
I cannot confirm what values the ISO or shutter (if any) are being changed to.
But you can hear the click as the aperture is stopped down or opened up, and another click when it returns to the locked setting.

Does it mean that the aperture changes only while the AF is working and returns to the initial locked aperture that we had chosen before?

I'd actually like to have information about the possibility to set and lock any aperture and shutter speed (1/50th).

Merci.

Right, when you go into movie mode, it will try to select a shutter at or near 1/focal length (example 1/80 with an 85mm lens), then select the aperture (example 5.6) and ISO.

When you you point the camera to a darker area (and the exposure is not locked), it will try to increase the ISO first, then pick a slower shutter speed -- but only up to a point -- it will still try to stay near 1/80 (say up to 1/50 but not slower), then select a larger aperture (example 2.8) and the shutter speed goes up back to or near 1/80) and adjust the ISO accordingly.

Now if you mount a 24mm lens, it will try to select 1/30 which is the minimum shutter speed. Therefore, you want to stay away from wide angle if you don't want too much motion blur. It will only select a higher shutter speed if it's already at or near lowest ISO (100) and the smallest aperture.

And, as Luis mentioned, with a zoom lens, it will adjust the speed to or near 1/focal length as you zoom in and out and adjust the ISO accordingly.

Now with a non-EF lens where the camera doesn't know the focal length, it seems to default to 1/40 or 1/50 -- for some people this may be close enough to the commonly used 1/60 setting for 30fps.

And it will go down to the minimum (1/30) when it's too dark and already at the max 3200 ISO. The LCD could show 1/10, but I don't think it actually goes down below 1/30 because the 'look' is the same between 1/30 and "1/10" -- there are no dropped frames, the exposure is the same, and it's not combining multiple frames into one blurred image (like the 'slow shutter' mode in other video cameras).

As already mentioned in another thread, it will go faster than 1/125. Unlike with minimum speed (where it shows a false 1/10 speed), you can actually see the exposure being adjusted as you point the camera at a brigher area and the speed goes faster than 1/125 and the ISO already at min 100 (the aperture is obviously not changing because it's a non-EF lens).



Then here's the kicker -- I mounted an EF 300mm lens and it's showing 1/320 (even while recording) which contradicts what's being said about the 1/125 limit ! Same thing with a EF 70-200 -- it goes up to 1/200. I've only done this indoors (pointing the lens at a flourescent light) -- I have yet to test this outdoors to confirm if the exposure is actually changing (between 1/125 and higher). It's more difficult to test this with an EF lens than with a non-EF lens (where you can manually select a larger aperture to force it to minimum ISO 100 and faster than 1/125 just by pointing it at a light. With an EF lens, I would need to shoot outside where it's really bright, with the lens (automatically) stopped down to F32 and minimum ISO 100 before it would go higher than 1/125.

What a mess . . . Isn't there any solution for simple control over aperture (no manual lenses) and over shutter speed?

I have explained these steps in a little more detail here: How To Use Video Mode on the Canon 5D MK II on Vimeo

Please refer to Note 3. It is working perfectly on my camera to get manual control over my ISO and Lock my aperture to wide open. Once again the only way you can get your shutter to change is if you are in plenty of light (outside during the day) and you get your ISO locked to 100 then when you move the exposure compensation wheel you have manual control of your shutter... It's working perfect for all my tests and I'm happy with the results: http://tylerginter.smugmug.com/galle...34710937_p2uiT Your results may vary so sorry... :(

Tyler,

I watched your video and it's interesting. One thing I'd like to mention thoug is that you can lock settings in exposure simulation, as long as you use Av or Tv mode. What's frustrating though is that exposure simulation is nothing more than a simulation... You can change the aperture and it'll simulate the exposure level you'd get at that aperture, but actual lens aperture remains constant. :( Bummer!
One last thing I'd like to share is that auto exposure seems to skip several aperture options when it seeks the perfect exposure. For example, on my sigma 24-70 2.8 the apertures it seems to want to stick to are 2.8, 5.6, 16 and 32. This is also a pain because sometimes 5.6 is still too shallow and 16 is way to deep DOF-wise. Sometimes I find the camera wanting to shoot 1/30th f32 iso3200 in broad daylight, WTF!

Canon should be ashamed of themselves.

As for the Av and Tv modes I figured that out and included those steps in Note 3 which you can read below the video. Those steps are working perfectly for me and here is an example to prove it. I shot these two examples at 1/30, ISO 1000 and F 3.5

Still frame extracted from video:
www.comcamdaily.com/5dmkii/still from video.PCT

Photo shot in manual mode:
www.comcamdaily.com/5dmkii/still photo.JPG

As you can see the DOF and Exposure are identical on both of these. This was all done under exposure simulation and I had complete control of my ISO and Aperture wide open. I do not have control of Shutter unless there is enough light to get my ISO down to 100 but in this case there wasn't enough light...

Perhaps pointing it to a light no?

I think I need to do another video tutorial... This is so hard to explain without actually showing people how it works...

If I'm using an EF lens with a max aperture of 1.4, does the method allow you to select an aperture or are you required to use max aperture (1.4) only ?
Can you clarify ?

Also, does your method take into consideration that the camera defaults at or close to 1/focal length shutter speed, and that the shutter speed changes as you zoom ?

Yes this method only works with the aperture wide open and yes the shutter speeds do play a roll in your zoom. Once again this is just a way to lock down your aperture so it is wide open and have manual control of your ISO. It is far more consistent than other methods I have tried. It isn't complete control but at least you can trust that your exposure won't change and your ISO won't go above what you want it to and your aperture can be locked to wide open so you can get the most out of your lens. When you are outside in daylight you also have the luxury of adjusting your shutter speed once your ISO drops to 100. Not perfect but it works for me and gives me all the control I need! :)

Thanks for the clarification.
The reason I had to ask is because you mentioned you had 'total control over ISO and aperture' but now I know it's not the case -- it's not practical to shoot at 1.4 unless that's what you want and/or you don't have enough light available. And you compared it with the DOF preview/twist method in the Vimeo post -- but the DOF preview method allows any aperture so it cannot be compared with your method.

Yeah sorry for the confusion. I fixed it where I accidentally said total control over both in my second post by my first post clearly said "to get manual control over my ISO and Lock my aperture to wide open."

What method is this?

Merci.

Tyler,

Great info overall, thanks. Just an additional note... You can start increasing shutter speed once iso reaches 100 under normal circumstances and if you enable highlight tone priority, shutter speed will go up once iso reaches 200 ;)

So far, this seems to be as good as it gets for manual control. Now if only we could find a way to reliably get the camera to do, say, max aperture, iso 800, 1/60th with a short focal length like 20mm we would be golden :)

PS. I'd love to have a word with whoever wrote the algorithm for auto exposure at canon. Who told him it was a good idea to make shutter speed stick at 1/focal length seconds? Not to mention the aperture stepping, it's like, very very very shallow DOF or infinite.

The auto exposure with lock limit wouldn't be such a PITA if it wasn't for the flawed auto exposure algorithm. :)

It's the "use at your own risk" method.

Many cameras (even back to the film days) have a depth-of-field preview button that allows you to view through the viewfinder what the image (including DOF) would look like with the lens stopped down to the selected aperture.

The trick is to unlock/twist the lens from the Canon body before releasing the DOF preview button so that the electronic contacts are disconnected, and the lens will remain at the selected aperture.

I have not tried this myself so I cannot comment further.

Oh Awesome tip on the highlight tone priority setting :) Yeah I agree with what you are saying here. Canon lost there mind with their algorithms.. I mean the workarounds are close but imagine how powerful this baby could be with manual control even to a very limited extent... There has to be reasoning behind this, I wish they would just let us know why they didn't put it in the camera. I'm really starting to think they just don't want to lose all their video sales and it's a big conspiracy. Think if this camera had 24/25p and full manual controls... Who would buy their video cameras??? Just saying...

I understand the occasional specialized use for high shutter speed, but isn't the bigger problem keeping shutter at 1/30 or 1/60?

1/30th? Isn't it too slow?

I just checked whether the shutter speed higher than 1/125 being displayed on the LCD when you mount an EF telephoto lens is accurate or not.

The result = NO.

I mounted an EF 300 and shot a still picture at 1/320 and you can see the fan blades:
http://www.palsomedia.com/canon5d2/s..._320_speed.jpg


But on the video with the LCD showing 1/320, the fan is completely blurred:
http://www.palsomedia.com/canon5d2/s...ed_display.jpg


With a non-EF lens, it does go faster than 1/125. Here's one at 1/400:
http://www.palsomedia.com/canon5d2/s...nonEF_lens.jpg

I assume that a still photo of 1/125 will look the same?

I've got an old turntable. That could be perfect for shutter speed tests.