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Old April 5th, 2010, 04:52 PM   #1
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Learning to focus manually - need tips

Almost everyone here seems to use manual focus, so I want to also. However, I can't seem to trust my eyes so I keep overshooting and undershooting the proper focus point. I'm never sure when I've nailed the focus. How do you guys do it?
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Old April 5th, 2010, 05:06 PM   #2
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Paul,

You didn't mention whether you use the EX1(r) or EX3. I've go the EX3 sot he viewfinder is a more useful for focusing. But, whenever possible I use my SmallHD monitor to aid in focusing and framing. With that I can really rely on just focusing as I see it on the screen.

When I can't use that, if I am doing a movie shoot where I can set up each take and take my time, I zoom all the way in on what I want to focus on, say an eye, nose, hand, whatever, set my focus then zoom back out to the framing I want.

When I'm doing a live event like a concert or sporting event I rely on peaking. For these events I'm usually further away from my subject and I don't zoom nearly as tight so I have a lot more depth of field.

I also rely on taking distance measurements using a laser measuring device and keep the distance readout on on my screen. then I can see if my focus is within the distances I've measured off.

Garrett
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Old April 5th, 2010, 05:10 PM   #3
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Forgot to mention, the best advice for learning to use manual focus, just plain old practice, and a lot of it.

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Old April 5th, 2010, 05:27 PM   #4
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I use peaking most of the time. Peaking can be fooled, so I use Garrett's "zoom in, zoom out" trick too, if I have the time, but I really depend on peaking.

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Old April 5th, 2010, 06:02 PM   #5
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gotta stuff your Eye right up to something:
you certannly cant do it back from the viewer , because such a small viewer can be very soft in focus and you dont notice.
when you try and view small viewers , with thier already less than full native resolution, it needs to fill your face with view, not be some tiny PDA your looking at :-)
once your that close, any softness will show up better.
be sure to adjust any diopter to the Text in the viewer not the soft picture, you should be able to see seperated pixels of the text , when you set the diopter.

with actual linked lens movements: when you lock the ring to the actual lens , with the Full auto, you have full control of the lens itself, no more digital junk inbetween you and the lens.

this form of peaking:
(which i dont like) grows :-) when you rotate one way and it is shrinking , your going the wrong way, when it grows your going the right way, so you can use the Size of the peaking to PRE-determine that your headed in the correct direction. so you dont go OUT to get IN focus, i hate when people do that, as it was better off a tiny bit soft than wacking it out to see why it was soft Duhhh. to bad the peaking in these is very contrast dependant, but at least they didnt toss it out.

Practice: only thing you can do is keep shooting, dont stop shooting. if you had a 8hour gig you would do it Right? well then go shoot 8 hours now, before its to late.

Focus ASSist: either that or depend on the machine, and use the assist focus :-( leave it in partial manual (lens not locked) Set focus assist on in menu. You then focus on the intended target , it finishes for you. i think that is only good if you Can or Have a cutaway, or have time to set things, so you and the machine, can screw it up when your view wont be used.
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Old April 5th, 2010, 06:28 PM   #6
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Quote:
Originally Posted by Garrett Low View Post
When I can't use that, if I am doing a movie shoot where I can set up each take and take my time, I zoom all the way in on what I want to focus on, say an eye, nose, hand, whatever, set my focus then zoom back out to the framing I want.
Hey, careful with this and the backfocus issue!

Since I know about this I have attached a Siemens Star to the back of my clapperboard and I use peaking to focus.
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Old April 5th, 2010, 07:18 PM   #7
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Originally Posted by Ivan Gomez Villafane View Post
Hey, careful with this and the backfocus issue
Very good point Ivan. Backfocus is something you have to check. I don't just set my focus and let it go. usually when I'm able to do this I can also use my monitor so it becomes a system of checks and redundancies. I usually don't rely on just one system and most of the time I use my distance finder to double check my focus.

Peaking takes some getting use to but after a while you get use to it. It still gives me trouble with it sometimes though. Especially when I'm shooting a dance show with a lot of glimmering outfits.


-Garrett
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Old April 6th, 2010, 03:37 PM   #8
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Originally Posted by Clark Peters View Post
I use peaking most of the time. Peaking can be fooled
Yes. Peaking can be fooled at lower exposure because it has a constant threshold rather than one that adjusts for the entire scene. Peaking can be advanced with a better peaking display, although I do appreciate the overlay in its current implementation:

Perhaps this would be best on a black&white rendition of the scene :
1) One color for absolute peaking showing sharpness (pixel-to-pixel contrast differences) that are near sensor resolution
2) Second color relative peaking showing the sharpest details in the scene. Even for unfocused or subjects with smooth color gradients, a portion of the scene would usually have more detail
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Old April 6th, 2010, 05:40 PM   #9
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I would say that if you are filming people look at their hair or at a pattern on their clothes to double check. If you are using peaking you'll most likely see the effect there. Also, if something looks "soft" creep the focus forward (closer to you) because that's probably the right way to go. I try not to bust the shot with a zoom in/zoom out, plus I think sometimes if the back focus is not absolutely perfect that may not work anyway.
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Old April 7th, 2010, 11:04 AM   #10
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Another suggestion. Today I focussed with a Nikon telelens on my EX3 and thought my subject was in focus. Then I switched of my ND filter and opened the iris a few stops to get the same exposure. Due to the decreased DOF I suddenly noticed the subject was just out of focus. So, when focussing it helps to do that with wide aparture / iris open, and after that close the iris to the right position. Especially helpful when working with tele lenses and of course only if the situation allows for such a procedure.
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Old April 7th, 2010, 05:09 PM   #11
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@ Cees:

opening iris decreases the depth of field.
This means a shot can be focused at stop 5.6, but out of focus at 1.9. Chances are very big opening the iris will place the focal point at the wrong distance.

(BTW, I suppose you meant putting ND on and opening iris, or ND off and closing iris.... no offence...)

Zooming in decreases depth of field as well (just for the record, just in case some stumbles into this topic and doesn't know, so (s)he gets confused by mixed results)
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Old April 7th, 2010, 09:22 PM   #12
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While it is true that telephoto lenses have less depth of field, I have always found that wider shots are out of focus more often than shots with longer lenses because we don't always see the 'softness' of the subject until it is truly blown up to a bigger size. I think that's interesting!
Also, don't forget about the focus enhance button on the EX3 (is there one on the EX1?) which is on the handgrip. When it is pushed it blows up the image (in the viewfinder only, not the recorded image) which makes it easier to see the focus, and then it reverts back to normal after a few seconds, or when you push the button again.
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Old April 7th, 2010, 10:44 PM   #13
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If I am doing controlled action, I use a Siemens chart on an A4 sized paper (laminated over punch holed paper so that it does not split apart).

If I am using a groundglass 35mm adaptor, I also check relay focus after every powerdown and restart with a resolution chart.

If I am recording an event like a court ceremonial sitting and have opportunity for prior preparation, I find key reference points in the room, set up a Siemens chart, note the distance numbers on a clipboard, copy them onto a piece of gaffer and tape them onto the camera so that if I become lost, I can get back in the ballpark quickly.

Very helpful if you happen to be operating two cameras from a confined position, ie., CAM 1, towards judge's bench, CAM 2, bar table and gallery but also rolling both cameras on common subject in close and wide views for smooth transitions when succeeding speakers take their turns.

This kind of foolish camera operating can become very confusing otherwise.

I use peaking always as my eyesight is not all that it could be.

I always use the focus assist button when I am permitted for same reasons. It is there so why not use it.

I do not use the EX1 autofocus at all as it seems to lose itself. This was a disappointment after the autofocus on the Z1/FX1. That I found to be fantastic, best used in bursts to establish then locked off to avoid it hunting.

For a concert event where I was one of several camera ops using JVC GY-HD100s, (wonderful camera for the job with a totally manual lens but a very ordinary LCD screen) I took along a LCD TV and plugged that in as a monitor for trimming focus and noting my reference points, individual microphones, centres of keyboards, drum kits etc. It made a huge difference to my confidence.

Last edited by Bob Hart; April 7th, 2010 at 10:54 PM. Reason: error
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Old April 8th, 2010, 02:10 AM   #14
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Quote:
Originally Posted by Walter Brokx View Post
@ Cees:

opening iris decreases the depth of field.
This means a shot can be focused at stop 5.6, but out of focus at 1.9. Chances are very big opening the iris will place the focal point at the wrong distance.

(BTW, I suppose you meant putting ND on and opening iris, or ND off and closing iris.... no offence...)

Zooming in decreases depth of field as well (just for the record, just in case some stumbles into this topic and doesn't know, so (s)he gets confused by mixed results)
@ Walter. I say the same as you do, but draw another conclusion. At 5.6 DOF is deeper than at 1.9 (as you say as well). This means that if your subject is in focus at 1.9 (with a very small DOF), it will certainly be in focus when you close iris to 5.6 and DOF increases.

The other way around: You might think your subject is in focus at 5.6, just because DOF is so deep. Once you close iris to 1.9, DOF decreases and you find out that you subject was not at the actual focus point at all.
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Old April 8th, 2010, 03:57 AM   #15
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One more question to the backfocus problem, please.
I always zoom in in full manual mode, find focus with peaking on an object in the distance I would like to film, and zoom back. So, of course, if the backfocus is wrong, this can cause unusable footage. I had this once with my VX2100. I tested during day with iris at f5.6, all seemed fine, but at night with f1.9 it was obviuos. This happened after a repair/check at an authorized Sony Service Center.

But: if I check at home, EX1R via HDMI directly connected to a 50'' plasma TV, film out of the open window in similar conditions as I usully film (objects in 200-500m distance with Z0, f1.9), zooming in and out, and while zoomed in the image is sharp on the plasma as wall as when zooed out - do I have to worry at all that this could not work in real life conditions? Or can I trust it and just should check after a bump of the camera or regulary every month or so?

Thanks for any hint,
Markus
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