Temporary wide open focus mode ?

[Les Dittert]

I was wondering if there is a trick or workaround to get the 'single' focus mode to work like an SLR, that is to open the lens, focus, then return the iris to where I had it .
Am I missing something ? It's a pretty obvious strategy for 'single' focus mode. Doing these steps manually is cumbersome. I'm using Tokina 11-16mm and various other EF mount lens's.
Thanks!

 

[stu aull]

Mine seems to do just that - tho its a pretty s-l-o-w action.

Same lens. (also same on 24-70; 70-200 Canons). Latest firmware - tho this has "worked" for months on mine...

Stu Aull
SX 199
Alaska

 

[Les Dittert]

Interesting,
So it opens the iris temporarily? Does it show a brighter image for a moment on the LCD While the focus is occurring? Should this work on a Tokina 11-16 lens? My electronic aperture control is working okay.
I'm trying to figure out why mine isn't doing this.
Thanks for responding.

 

[Trent Lillehaugen]

The AF does not automatically change the aperture. The picture may temporarily brighten but that is not due to changing he aperture.

 

[stu aull]

huh.
I assumed it was the iris. The effect, at least in low (room) light is quite dramatic. It brightens, hunts for the focus, then returns to original levels once it locks (or if it finally gives up and can't...)
Only when the camera is NOT recording. In record mode, the iris (or, the effect) does not occur. I had pointed this out to the RED Techs and they said that is normal. Or at least, not unusual. I will pay more attention to what seems to be going on, see if I can hear the iris motor cycling, etc.
I presumed every RED did this...

Stu Aull
SX 199
Alaska

 

[Les Dittert]

The AF does not automatically change the aperture. The picture may temporarily brighten but that is not due to changing he aperture.

Trent, is this feature on a list to add ? Seems easy to implement, and would really help it focus more accurately.

 

[stu aull]

Have to say I am surprised my scarlet has to "work" so hard to find focus, when my beat-up old Canon Rebel just pops instantaneously with the touch of a button. And of course the new ones (D's etc) are just spectacular. Is there some sort of patented tech Canon uses that forces RED, etc into workarounds for implementation? I am a bit boggled that this amazing camera system has such a mediocre response with autofocusing.

Stu Aull
SX 199
Alaska

 

[Les Dittert]

Stu, you can't compare DSLR focus unless you are in 'Live view' mode, as in when you are watching the live picture on the LCD.
That is a lot harder. Normally DSLR uses phase detection with dedicated sensors for fast focus. Live view is slower because it has to use the image and look for contrast.

 

[Maik Müller]

Yup, if you compare AF then you shouldn't do it with DSLRs, but there are enough mirrorless cams that work similar to our REDs. The EOS-M is a different story again, so are Sony's SLT-cameras.

What makes probably a difference too is the framerate, most of those other mirrorless toys do run with higher fps/hz than 24/30, so AF can do it's hunt for focus faster. Shutter speed could make a difference too, less blur = easier focus detection.

Just thinking out loud, i haven't done any tests on that matter.

 

[stu aull]

Stu, you can't compare DSLR focus unless you are in 'Live view' mode, as in when you are watching the live picture on the LCD.
That is a lot harder. Normally DSLR uses phase detection with dedicated sensors for fast focus. Live view is slower because it has to use the image and look for contrast.

Fair enough. Can I compare it to my dumb little Canon V30 HDV cam's autofocus then? Not trying to be a smart@ss here. Just would LOVE to have my L'il Leafblower do what most prosumer-ish video gear has managed for the past 5-6 yrs. These (Red) cams do some absolutely amazing things. I would just like autofocus response to be one of them.

Stu Aull
SX 199
Alaska