Live view focus

[joe_cormier]

<p>I see that some photographers use live view to manually focus their camera. If I do not have 20/20 vision will the image be<br>

as sharp as auto focus? If not, any suggestions on using live view without 20/20 vision? Lastly, are best results obtained by<br>

focusing at maximum zoom and then recomposing at a lesser magnification? As always, thanks in advance.<br>

Joe</p>

<p> </p>

[Andrew Garrard]

<p>Joe, all you need to be able to do is see the pixels on the LCD. In fact, you don't even need to be able to see that, since Nikon let you magnify the live view greater than 100%. Not that the live view on some camera (e.g. D800) is using all of the sensor data. The best results probably come from composing first, then focussing at maximum zoom (you can zoom in anywhere on the screen) - otherwise the focus point will shift when you recompose.<br />

<br />

You can get loupes to place over the LCD screen if you really need this. Good luck!</p>

[mike_halliwell]

<p>You can easily use AF in Live View. The main advantage of fully zooming in Live View (ie not optically) is that you can ensure visually where or what the camera is actually focusing on.</p>

<p>Sometimes when I'm out shooting and I've left my (driving) contact lenses in, I can't see the back screen well enough to focus manually, I allow the camera to Live-View Auto-focus for me if I show it where to focus, ie move the single-point AF marker to where <em>I</em> want, a mid-ground flower maybe of a far off tree branch etc. Green Box=OK, Red Box=Not OK!</p>

<blockquote>

<p>Lastly, are best results obtained by<br />focusing at maximum zoom and then recomposing at a lesser magnification?</p>

</blockquote>

<p>I'd say that might be OK with <em>some</em> lenses, but not most. The critical focus can change with focal length changes. I'm a great believer of actually trying this out for real with your own lens(es) and then critically looking at the results. Camera on a tripod with a static target, it should be fairly easy to see if this works for you and your set-up.</p>

<p>EDIT. I read the OP 'zooming' phrase as optical zoom, where he probably meant Live-View zoom!.. my mistake.</p>

[dan_south]

<p>Joe, if like me you're not as young as you used to be, consider using a good pair of reading glasses when looking at the live view image on the LCD. You can buy cheap ones at the drugstore, but they won't have the coatings necessary to subdue glare and reflection. </p>

<p>My preference is to compose the scene first and then focus just before exposing. You don't want to move the camera after focusing.</p>

<p>One advantage to live view focusing is that it can be done anywhere within the image. You don't need to place an object under one of the AF focus points, so there should be no reason to recompose. This is also the case when using AUTO focus in live view, something that I would recommend that you try. It's a different type of auto focus (contrast detection), and I find that it is generally very accurate. It's just a little slow. Typically, it takes about a full second to lock in, so it's not suitable for moving subjects.</p>

[rodeo_joe1]

<p>".... will the image be as sharp as auto focus?" - Probably a lot sharper!</p>

<p>Joe, if Live View is to become your main way of focusing, you might want to consider getting some sort of hood for the screen. It's fine in low light, but in bright sunlight the screen brightness just isn't enough to overcome its surface glare. Maybe we should just go back to the old black dark-cloth over our heads?</p>

[joe_cormier]

<p>Thanks for all the excellent info. Will experiment with all suggestions! Joe</p>

[samuel_lipoff]

<p>I have definitely used a dark cloth with my D700 in Live View before!</p>

[elliot1]

<p>The green dot auto focus confirmation in the viewfinder is pretty accurate.</p>

[eric_bowles1]

<p>I'm not sure of how you are activating AF, but if you use the AF-on approach rather than the shutter, Live View is even better. <br>

My approach is to get a rough focus and composition first - typically through the viewfinder. It does not have to be perfect as you will focus more accurately using Live View. Then I activate Live View and move the AF cursor to the desired area of the image. I typically zoom in for a much closer look, then activate AF using the AF-On button. The red box of the cursor turns green if focus is achieved. I can still manually adjust focus if desired. <br>

One of the related uses of Live View is to check focus on other areas of the image. You can move the cursor and zoom in to look at specific elements of the image.<br>

One word of caution. There are different ways that Live View is deployed depending on your camera. The newest cameras initiate mirror up with Live View. Earlier cameras do not - and there can be some vibration. <br>

Another note - the Contrast Detect AF used in Live View is a little slower than normal Phase Detect AF. But Contrast Detect is more accurate and overrides any lens calibration issues.</p>