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Focus problems with new EX1R

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Kelli Smith
Focus problems with new EX1R
on Jun 15, 2012 at 4:41:07 am

Our shop just bought a new EX1R. We've used it on 4 shoots so far. Our camerapeople seem to be having a real problem focusing. Maybe we shouldn't have gotten a camera with this short of depth of field, as we film in all sorts of scenarios (mostly corporate). When we are filming seminars with a dude next to a Powerpoint screen, some of the footage is coming back quite soft. Camera op swears he saw peaking on the LCD. Maybe the depth of field from the back of the room is problematic? Have tried full manual mode (mostly in focus, some b-roll is soft), manual focus with asking the camera to help by using "push auto" (this was horrible). All of these shoots so far have been pretty "normal", not run and gun. I shudder to think what that footage would look like, as any of the auto focus and MF assist settings seem to be not at all an option. I know there is a learning curve, and we have Doug Jensen's DVD and field guide. Just hoping for some guidance, as so far the footage is not where we need it to be. I know this is a rambling post, just frustrated as the post production person. Previous cameras were Z1Us. Love the tapeless workflow!


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Don Greening
Re: Focus problems with new EX1R
on Jun 15, 2012 at 5:32:30 am

If the camera's back focus is off then the peaking shouldn't be trusted. The camera's built in flange back routine for adjusting the back focus can be done in-house but since the camera is so new it would be in your best interests to take the camera back to where you bought it and get them to do the adjustment. To find out for sure if the back focus is out first:

  • set it on full manual focus
  • zoom all the way in to an object
  • set focus
  • zoom back full wide
  • zoom back in to the object

if the focus held then the back focus is fine. If the focus is soft then you need the adjustment done.

- Don

Don Greening
A Vancouver Video Production Company
Reeltime Videoworks
http://www.reeltimevideoworks.com


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Kelli Smith
Re: Focus problems with new EX1R
on Jun 15, 2012 at 6:02:04 pm

It didn't seem to be a backfocus issue, but we went ahead and did the calibration procedure with a star chart. Bought the camera from B&H, so not easy to get their help ; )

On yesterday's shoot, I think the iris was opened all of the way up, which created too shallow a depth of field. This was a shot from the back of an amphitheatre style classroom, backs of heads between the camera and a pacing lecturer. The focus ring was AF/MF, focus switch manual, MF Assist off, push auto was used at times.

I think that push auto shouldn't have been used, as it would focus on the backs of heads, instead of lecturers. The camera op was just looking for some help with the focus, but this wasn't the way to go. the push auto on the Z1Us did tend to help, so that's the disconnect.

So next time, it is probably better to dial in a little gain, if we are unable to supplement lighting, so that the iris can be stopped down, and this will create a deeper depth of field. Also, full manual mode and don't try to get any help from the camera. And maybe need an external monitor with peaking turned on.

Does this sound like a fair post mortem? Just trying to learn from our mistakes, thanks for any help.


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Don Greening
Re: Focus problems with new EX1R
on Jun 15, 2012 at 8:41:02 pm

Kelli, yeah manual focus is the only way to go, especially when the zoom and iris are maxed out. The human eye is a much more accurate device than any focus assist, regardless of price.

If at all possible try not to use any picture gain because the EX1R's imagers are a little noisy to begin with and gaining up will just accentuate the issue. It's absolutely okay to use the iris wide open as long as you stay on full manual focus (pull the focus ring back until it clicks into manual). This way there will be no 'focus hunting' from the camera at all.

Zoom into your subject and use the expanded focus button on the hand grip. Set your focus and you're done. FYI unlike the Z1U, expanded focus can be used on the EX1R while recording to re-check focus periodically to make sure there is no lens breathing during the session. Since you are an experienced content creator you will know that a shallow depth of field will minimize the viewer's eyes from wandering away from what you want them to focus on.

Even though the EX1R's flip out screen is good enough for critical focus you may want to also use a larger on-camera field monitor in these instances to give your camera person more piece of mind during the session.

Hope this helps.

- Don

Don Greening
A Vancouver Video Production Company
Reeltime Videoworks
http://www.reeltimevideoworks.com


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Bob Tompkins
Re: Focus problems with new EX1R
on Jun 18, 2012 at 5:07:43 pm

Hi Kelli,

I have 6 EX-1r's which I use daily in low light situations using auto-focus all of the time. I shoot through two-way mirrors which drastically reduce the amount of light the camera gets. I have no problem achieving a crisp, in-focus picture with no undue effort. I would have to suggest that there is something wrong with that camera. If there is certified Sony dealer in your area I would bring it to them and have them look at it. They should not charge you since it is a warranteed camera but they may ridicule you for buying it from B&H (since everyone charges the same price for a Sony camera).

You should not be unhappy with the focus.



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Chris Babbitt
Re: Focus problems with new EX1R
on Jun 19, 2012 at 4:06:13 am

There actually has been a focus issue with some of these cameras. A friend of mine got Sony to replace his lens at no charge. It took some doing, but they eventually caved-in. In fact, i think it was out of warrenty.



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