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View Full Version : Locking the aperture on 85mm 1.2



AutumnFire@gmail.com
03-17-2009, 04:35 PM
So I understand that the 5dmk II will automatically close down the iris in video mode. Is there a way with some lenses, specifically the 85mm f/1.2 (mk. 1), to prevent the camera from controlling the aperture by taping over some or all of the contacts?

The reason I ask is that the 85mm lens focus-by-wire, so I assume that if I tape over all the pins, you will no longer be able to focus the lens, manually or automatically. Is this correct? Is there a magic combination, which disables aperture control, but leaves the focus functional?

Lee Wilson
03-18-2009, 04:34 AM
You can try and use ND filters to keep it open if you are after aperture control and want to be able to focus on your subject - or make your own variable ND filter.

egproductions
03-18-2009, 05:24 AM
Yes, this is the aperture control workaround for EF lenses:


Switch to any camera mode that allows you to adjust the aperture. (AV, M, etc.) and choose your desired aperture (this isn't neccessary if you want to shoot at wide open)
Hold down the DOF preview button while partially twisting off the lens (if you are in live view mode you will know you have twisted off the lens enough when live view automatically shuts down
either shoot with you lens half twisted or you contacts taped as you described above so that there is not communication between the camera and lens

Lee Wilson
03-18-2009, 05:53 AM
Yes, this is the aperture control workaround for EF lenses:


No, no, you have the name all wrong.

It is called the 'Canon professional depth of field control'.

:)

ESTEBEVERDE
03-18-2009, 09:57 AM
No, no, you have the name all wrong.

It is called the 'Canon professional depth of field control'.

:) :beer:

Eric Papa
03-18-2009, 10:44 AM
Yes, this is the aperture control workaround for EF lenses:


Switch to any camera mode that allows you to adjust the aperture. (AV, M, etc.) and choose your desired aperture (this isn't neccessary if you want to shoot at wide open)
Hold down the DOF preview button while partially twisting off the lens (if you are in live view mode you will know you have twisted off the lens enough when live view automatically shuts down
either shoot with you lens half twisted or you contacts taped as you described above so that there is not communication between the camera and lens



Thanks for the tip! I just tried this and the shutter can't make up its mind what to do. Anyone else having this issue?

xianchi
03-18-2009, 12:07 PM
Thanks for the tip! I just tried this and the shutter can't make up its mind what to do. Anyone else having this issue?

The once you do the steps described above, hit the exposure lock button and the shutter will stay constant.

booggerg2
03-18-2009, 12:21 PM
Yes, this is the aperture control workaround for EF lenses:


Switch to any camera mode that allows you to adjust the aperture. (AV, M, etc.) and choose your desired aperture (this isn't neccessary if you want to shoot at wide open)
Hold down the DOF preview button while partially twisting off the lens (if you are in live view mode you will know you have twisted off the lens enough when live view automatically shuts down
either shoot with you lens half twisted or you contacts taped as you described above so that there is not communication between the camera and lens



incorrect.. when you half twist the lens to freeze the aperture, you loose auto focus functionality on the Canon EF 85mm f/1.2 lens.

THere is no good way of enforcing larger aperture on the 85L other than to stack ND filters.

xianchi
03-18-2009, 12:43 PM
true but the Autos Focus function on this camera is useless for video so you are not losing much.

Lee Wilson
03-18-2009, 01:48 PM
. . . . but then you cannot focus while filming.

So you first need to focus on your subject, then do the above procedure.

Just like the pros do it.

Lee Wilson
03-18-2009, 01:52 PM
incorrect.. when you half twist the lens to freeze the aperture, you loose auto focus functionality on the Canon EF 85mm f/1.2 lens.

You lose all ability to focus :(

Eric Papa
03-18-2009, 03:40 PM
I tried to use my 85mm 1.2L with the redrock and it wouldn't work either now that you mention it.

works well on my 24 - 70mm 2.8L

What button is the exposure lock?

hdimages.ca
03-18-2009, 03:49 PM
just picked up my 5d mark 2 -wow. i have the set of nikon primes ,manual aperture control with the nikon adapter . shot in the dark last knight -wow- just need some spin on nd filters or mount up my redrock matte box sunny day set up.

Lee Wilson
03-18-2009, 04:07 PM
What button is the exposure lock?

http://img4.imageshack.us/img4/5974/86901296.gif

Eric Papa
03-18-2009, 04:24 PM
Thanks Lee, cool graphic by the way.

Im playing around with it trying to get the f at 2.8 and the shutter around 120

ESTEBEVERDE
03-18-2009, 04:50 PM
just picked up my 5d mark 2 -wow. i have the set of nikon primes ,manual aperture control with the nikon adapter . shot in the dark last knight -wow- just need some spin on nd filters or mount up my redrock matte box sunny day set up.


Specifically what primes do you have in your kit? :beer:

egproductions
03-19-2009, 06:13 AM
incorrect.. when you half twist the lens to freeze the aperture, you loose auto focus functionality on the Canon EF 85mm f/1.2 lens.

First of all auto focus is useless in video mode...the sensor is too big, the MP count is too high and the DOF is too shallow. The camera gets confused way too easily and you don't want that in your video. You want to set your focus first and then shoot on manual focus. It's true that you can use autofocus to get your initial focus but you can also use the live view 5x and 10x zoom in to achieve an even better focus than autofocus gets you on many occasions.

If you are using nikon lenses you are not going to have autofocus either and will have to use the above method of focusing as well.

If you know you always want to shoot at a certain aperture on the lens then you can figure out which contanct pins are supplying the lens with power and with focus information and tape off the rest. This will be annoying if you want to switch apertures though and in my opinion not worth it.

You lose all ability to focus :(

You don't loose all abillity to focus....:huh:

Only on some lenses (usually the cheaper ones) does it restrict focusing if you have the lens set to auto focus (such as the 50mm 1.8). You need to make sure your lens is set to manual focus you do the lens twist off.

Lee Wilson
03-19-2009, 08:58 AM
You lose all ability to focus :(

You don't loose all abillity to focus....:huh:


Sorry ! You are quite right, I didn't spot that the 85mm has manual focus.

reem12
03-26-2009, 10:13 PM
od the exposure lock button need to be held down while shooting to maintain a constant shutter or is there a way to hit the button once to make the constant shutter. it seems when i'm shooting i half to keep my finger on the button to maintain shutter. if anyone knows the process please share. thanks.

Lee Wilson
03-27-2009, 05:37 AM
od the exposure lock button need to be held down while shooting to maintain a constant shutter or is there a way to hit the button once to make the constant shutter. it seems when i'm shooting i half to keep my finger on the button to maintain shutter. if anyone knows the process please share. thanks.


You only need to press the AE lock button once (press it and then take your finger off it).

If it does not stay locked for long (only a few seconds) - you need to go into the menus and change the 'metering timer' to a longer setting to stop the AE lock switching off too quickly - (by default it is on some stupidly short setting).

Do this . . .

Menu >> scroll across to the second yellow spanner (4th icon from right) >> go to 'LiveView / Movie Function' >> scroll down to 'Metering timer' >> change the setting to '30 minutes'.

Now when you press the AE lock button, it will stay locked for 30 minutes (and for you this means the shutter speed will remain constant for 30 minutes).

reem12
03-27-2009, 08:29 AM
hi lee. there seems to be no problem lockng exposure while in record but it will not lock in standby while monitoring.

Lee Wilson
03-27-2009, 10:03 PM
hi lee. there seems to be no problem lockng exposure while in record but it will not lock in standby while monitoring.

You would have to be more (much more) specific for a good online diagnosis.