Red Focus - PL calibrate then Canon Mount

[roryhinds]

If you set the back focus on the Epic with the Red Focus using a PL mount then switch the mount out to a Canon Mount is the back focus still good?
Or do you need a Canon Mount Red Focus to set back focus when using a Canon mount?

 

[Douglas Underdahl]

I think you are safe to check depth aka flange focal distance using the PL mount, then switching to the Canon mount. The Red Canon mount and the Red PL mount are likely machined to very similar tolerances, and probably you are going to eye focus with your Canon lenses anyway? But if you are going to tape focus with your Canon lenses and you therefore need the focus scales on the Canon lenses to be very accurate, I would check them with the Epic and zoom function with a chart and large monitor at all important distances and place new focus marks on each lens with letraset type tape. Tedious and time consuming, but this is what professional ACs do with that extra day of prep before the feature. And even if you set flange focal distance with a Canon mount installed, you may have to check the focus scale on each Canon lens. You can add extra marks this way also. Whew.

 

[JamminJG]

this is a question for RED support. RED has always said that we, owner/operators, would hardly ever need to worry about back-focus. Then in the RED one days, all the old skool dp's insisted that back focus needed to be calibrated just like the crappy old HD camera like the CineAlta need to be. Like every frickin time you move the camera. So, people were monkeying around with RED One backfocus much more than they ever needed to. So, RED finally came out with an un-necessary piece of equipment, called the RED Focus, just for those old skool hacks to help them sleep better at night. Now, thanks to so-called "professional industry" hysteria, we all think we need this un-necessary piece of equipment. Of course, RED isn't going to tell you that. But those of us who've been working with RED since 08 already know not to bother with it. As ted once said, if the backfocus on your red is giving you problems, its time to send it in to red for them to fix the damage you have already done.

This is ALL true. I witnessed it myself. The dp would order a backfocus check, then hours later, they'd give up and move onto camera "b" and bitch about REDs. When they themselves messed it up.

 

[CJ Roy]

The Red-Focus is pretty invaluable when there's seems to be a back-focus issue. Sometimes the marks on lenses just inexplicably tend to drift throughout the day. It's a very simple way to isolate the issue and see if it is the lens or the camera. Not knowing which, can make life pretty miserable on set.