Olympus Focussing

People, old time photographers as well as new generation users set a lot of store on autofocus. Or, the other extreme want the best manual control for manual focus. This article will, over time, cover this topic more comprehensively.

For now, it's worth detailing what Focus features Olympus gives you.

Settings that affect Auto/Manual Focus

Cog A

Cog A

Cog A

Cog A

Cog A

Cog A

Cog A

Cog A

Cog A

Cog A

Cog A

Cog A

Cog A

Cog D

Camera 1

AF Mode

AF Mode

Full-time AF

Reset Lens

BULB/TIME Focusing

Focus Ring

MF Assist

MF Assist

Set Home

AF Illuminat.

Face Priority

AF Area Pointer

C-AF Lock

Frame Rate

Picture Mode

Still Picture

Movie

On / Off

Magnify

Peaking

Full Area

Single Point

Single Point -Small

Cluster

Face Priority Off

Face Priority On

Face Priority and Left Eye Detect On

Face Priority and Right Eye Detect On

Face Priority and Nearest Eye Detect

On / Off

Off

Low

Normal

High

Normal

High

Vivid

This allows you to choose between MF / S-AF / S-AF-M / C-AF-TR - this is the same setting as that in the Super Control Panel

For effect on video focussing, see William Porter:

From an Olympus response posted on the M43.com forum

The full time auto-focus setting behaves like the C-AF setting, constantly focusing, and refocusing when the focus is lost in order to get focus again. This behavior could be compared to a camcorder, which performs in a similar fashion. You could conceivably use it in a situation like a school play or taking pictures of the children at a family event. In such situations their movements can be unpredictable, and so having the camera already locked onto your subject would be to your advantage.

The only negative aspect of this setting is that it will use power every time is focuses, so your battery life could potentially diminish faster than it would otherwise by using this setting. Normally focusing only begins once you press the shutter button down half-way, etc.

By default this auto-focus feature will be available during video shooting unless you set it otherwise.

"Can this mode mode in conjunction with AF-C-Tr (Tracking)?"

Yes, think of it this way: The Full time AF is constantly focusing until you press the shutter button down half-way in preparation to take a picture. Once you do that, your chosen focus mode (such as C-AF+TR) is now being used. If you release the button, the camera will return to full-time auto focusing.

Reset Lens = Yes means that when you turn the camera off and then on, the lens focus position will be set to infinity. If Reset Lens = No, the lens focus position stays at the last used position (assuming your AF Mode is Manual Focus.

Allows manual adjustment of the focus ring during BULB / TIME exposure

On / Off - if you rotate the focus ring, the liveview will magnify to the magnification you previously chose.

Related settings:

The magnification enlargement can be previously set in the following ways:

  • Cog K > Touch Screen Settings > On - to enable touch screen ability on the camera.

  • There are three choices for responding to tapping the Button Icon on the Touch Screen -

    • Off

    • Adjust Focus - Choose this

    • Trigger Shutter Release

  • Use the touch screen to engage the green frame - there is a vertical slider on the right, which you can touch to change the enlargement between 5x to 14x

or

    • Hold down the assigned Multi-Function Button and rotate the Front Dial until you switch the Multi Function Button to Focus Magnify Function.

    • Tap the Multi-Function Button and the Focus Magnify green frame will appear - use the Cursor Pads to adjust the frame position on Liveview.

    • Tap the Multi-Function Button again to magnify the view - use the Front and Back Dials to adjust the enlargement

    • Press the Ok button to exit Magnify operations

or

    • Tap the assigned Magnify Button to display the green frame.

    • Tap the same button again to magnify the view - use the Front and Back Dials to adjust the enlargement

    • Press the Ok button to exit Magnify operations

Cog D > LV Closeup Mode

This has nothing to do with macros or close up subjects. It has to do with what happens when you have the green frame displayed.

Mode 1

When you have engaged full screen magnified display, Half Press of the Shutter Release button will exit the magnified display.

Mode 2

When you have engaged full screen magnified display, Half Press of the Shutter Release button will cause autofocus to engage.

AF will not work with Four Thirds lenses.

Focus Peaking Colour

Cog D > Peaking Settings > White or Black

Note: On the E-M5 Mark 2 you have the choice of additional colours, Red or Yellow

Autofocus Lenses

If ON - when you rotate the focus ring of an autofocus lens, the Liveview will show focus peaking in the colour edging that you previously chose

Non electronic coupled lenses

  • Assign a Button to Focus Peaking (Use Cog B menu and choose an Fn button to assign)

  • Press the button to toggle Focus Peaking On / Off

Face Priority

When it works

  • Face Priority is a useful feature if you are shooting shallow DOF portraits and you have one person's face facing you.

  • If Metering is set to ESP pattern, Face Priority optimises exposure for faces.

When it doesn't work

  • It is problematical if you have more than one face in front of the camera and at different focus distances.

  • It can also be confused if you have no faces and the scene is dim.

  • Face Priority only works for the first shot in a burst sequence.

  • Eye Detect does not work in C-AF

  • Art Filters degrade Face / Eye Detect performance

    • With Four Thirds lenses, Face Detect does not work outside of the Phase Detect points.

Olympus Notes on Firmware Update 3.0 for OM-D E-M1

AF tracking during C-AF continuous shooting in continuous shooting H mode is supported.

Previously, in continuous shooting L mode 6.5 frames per second was possible, but now taking a maximum of 9 frames per second in continuous shooting H mode is possible.

Pekka Potka Article

This is the menu to set suitable amount of C-AF lock. Off means that E-M1 tries to change focus to a new object instantly and at High it is most reluctant to do so. This is something every user must test to find which setting is best for one´s type of photography.

High improves AF performance in good light but may perform worse in low light

With Contrast +1 as discussed by Gary Ayton - increases the contrast of the Liveview feed for CDAF operations - if this is not how your prefer JPEGs look like, capture raw only (which should reduce file save time to the SD card.

Selecting how the two buttons (shutter release and assigned AEL/AFL button) work for S-AF

Cog A > AEL / AFL > S-AF Mode

Mode 1

Half Press of the Shutter Button activates AF and locks exposure. If you half press and hold the half press, and wave your camera around, both the focus and the exposure will be fixed and not fluctuate.

If your exposure calculation is set to P/A/S,

touching the assigned AEL/AFL function locks exposure (you do not have to hold it down) - you will see the AEL icon in green in the LCD. This means exposure is locked without pressing any other button. For subsequent shots, the exposure will still be held constant until you touch the AEL/AFL button again.

If your exposure calculation is set to M of P/A/S/M - AEL/AFL function is disabled.

Mode 2

Half Press of Shutter Button activates S-AF but does not lock exposure - this allows you to separately target a focus area but the exposure measurement will float as you point the camera at different parts of the scene.

If your exposure calculation is set to P/A/S,

touching the assigned AEL/AFL function locks exposure (you do not have to hold it down) - you will see the AEL icon in green in the LCD. This means exposure is locked without pressing any other button. For subsequent shots, the exposure will still be held constant until you touch the AEL/AFL button again.

If your exposure calculation is set to M of P/A/S/M - AEL/AFL function is disabled.

Mode 3

Half Press of the Shutter Button activates Exposure Lock.

Pressing the assigned AEL/AFL button will activate S-AF.

This is useful in avoiding autofocus when you trigger the image capture. It is useful when the subject is moving to and fro about an aimpoint. Or there could be other objects in front of subject, moving in and out, obscuring your subject. You do not want the autofocus to follow the subject - if the subject is movement is faster than the camera+lens can cope, you will have a frustrating time locking focus

The technique is this: Point to the part of the subject you want to focus on. Press the assigned AEL/AFL button to activate auto focus. Release the AEL/AFL button - the camera will not adjust focus. Keep the subject in sight until such time as the subject itself moves back to focus, press the Shutter Release button to capture the image. See Back Button Focus

Selecting how the two buttons (shutter release and assigned AEL/AFL button) work for C-AF

Cog A > AEL / AFL > C-AF Mode

Selecting how the two buttons (shutter release and assigned AEL/AFL button) work for MF

Cog A > AEL / AFL > MF Mode

Mode 1

Half Press of the Shutter Button causes Exposure Lock.

Pressing the assigned AEL/AFL button causes Exposure Lock.

Mode 2

Half Press of the Shutter Button causes Exposure Lock.

Assigned AEL / AFL button - engages S-AF

In manual focus mode, you have opted to use the focus ring in either autofocus lenses or manual focus lenses to focus. For autofocus lenses, you can "cheat" by pressing the assigned AEL/AFL button to engage S-AF, which will bring the focus point to the best position for that time. Subsequently, you can use the focus ring to tune the focus to what you want.

This mode is useful for pre-set focus on slow focussing autofocus lenses for example, in street shooting. If the camera and lens cannot cope with the impromptu and quick movement of moving people, set the camera on MF, point to the distance you want, for example 6 ft / 2 metres, press the AEL/AFL to autofocus, then release and the lens will not auto adjust. See Back Button Focus

Selecting Auto Focus Points / Pattern

You can nominate a button to get into the Auto Focus Point / Pattern screen. Once there you can:

    • Select which single AF Point you want to use

    • Choose between:

      • a Normal size AF Point

      • a Small size AF Point

      • a Cluster of AF Points

      • all the AF Points

    • Select between

      • Face Priority Off

      • Face Priority On

      • Face Priority and Left Eye Detect On

      • Face Priority and Right Eye Detect On

      • Face Priority and Nearest Eye Detect

or you can nominate the Cursor Pads at the back of the camera to activate this screen

Touch designation of AF rectangle

The touch LCD has the following modes:

    • Touch is disabled

    • Touch causes focus and shutter trigger

    • Touch designates focus rectangle area.

The user interface is read thus:

    • If the icon show Touch Focus, you can touch the LCD and a green focus rectangle will appear and be designated for focussing.

      • If you hold your finger down on the green focus rectangle, AF will initiate (S-AF mode)

      • After the green focus rectangle appears, the icon will show as OFF - this means if you touch the icon again, then normal AF behaviour will resume and the green rectangle will disappear.

When does the E-M1 use the PDAF points and when does it do CDAF?

From Pekka Potka's article, the E-M1 uses PDAF by itself for Four Thirds lenses and a mix of PDAF + CDAF only with Continuous AF in Micro Four Thirds lenses. In all other AF modes with Micro Four Thirds lenses, the E-M1 uses CDAF points.

Darrell Young's book on Mastering the OM-D E-M1 has a free addendum on Firmware Update 3.0 (pdf)

Points noted:

  • C-AF works with PDAF at up to 9 fps on High speed sequential shooting

  • AF is updated frame to frame, WB and exposure are fixed on the first frame.

  • Set C-AF Lock to Normal

Tuning C-AF / Moving Subjects

Sports with older / cheaper MFT bodies

Sports shooting especially in dim light (for example basketball in dim gym halls) is a tough assignment for any camera. The pro premium bodies and bright lenses that cost heaps in all brands are the way to go but most of us aren't pro shooters, we only shoot the odd sports for our kids or family or friends for self enjoyment - therefore unwilling to spend big.

For those MFT camera bodies with lesser autofocus performance, here are some ideas:

    • Don't crop. MFT has a handicap with image noise at high ISO in dim light. If you crop, don't compare by saying "If I had this other camera and lens, it would be better"

    • Don't underexpose - underexposure increases noise.

    • Be realistic with your shutter speed. Find out what is the slowest shutter speed that works enough with your style and sports. If you bang on too high a shutter speed you tip the scales and force a high ISO.

    • Noise Reduction should be OFF - that is for tripod, long exposure astro not sports

    • Noise Filter - For jpeg, making a choice has impact. For raw, it does not have impact. Check the three settings and pick one to taste. If you are willing to edit the photos (even jpegs) you can switch that off - and use the computer to filter the noise

    • C-AF for bright sun is what it is, under dim light, it will not be great. Film manual focus shooters shot Manual Focus in the days before AF was designed. You don't have to use MF, you can use S-AF - yes, it can't just point and shoot, you have to plan the point where the moving subjects will be at a fixed distance that you have already determined and go ready. If you use C-AF, you can try Back Button Focus

    • Shoot black and white instead of colour. Dim dyms and courts have ugly green flouro or artificial lights anyway. Make your images look retro and think you are shooting film Tri-X boosted to ISO 1600 - you should see the grain we had to deal with.

    • JPEG will give more frames in buffer. raw will give you less frames in buffer.

    • EVF lag and Focus lag are different issues to buffer - there are settings for EVF and for AF that the frequent sports shooters can tell you about to optimise for sports. For example http://www.ayton.id.au/wiki/doku.php?id=photo:olympusem5_af

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