How do you check critical focus and image sharpness "in the field"?

[Jay86]

Ok, so I have been out n' about now thats its spring and been shooting mostly street stuff. I recently made my switch to Olympus and have yet to log serious hours with my E-M5 "in the field" but one thing I HATE is that I lost a shot that I otherwise could have re-taken while in the moment if I had just checked critical focus and image sharpness right away. So of course to check when reviewing the image on the back LCD screen I use the zoom feature on the focus point.

What Im wondering here is what zoom level do you EM-5 folks (or any M43 shooters really) usually use to determine wether the image is likely sharp and critical focus has been achieved: 2x, 3x, 5x, 7x, 10x, 14x?

I know this might sound like bit of a silly question really, but different zoom levels on the back of your screen show you different things. At some zoom levels is looks unacceptable and some its looks acceptable. Question is what zoom level check equates to a sharp/critical focus on your computer screen or print later on.

 

[Yohan Pamudji]

5x works for me. 7x and it starts looking like more than 100% zoom, but 5x - 7x is probably about right. 10x and it really starts looking wrong. Note that this is with an E-M5 shooting RAW. Maybe if shooting JPG or RAW+JPG it would use the full size JPG when reviewing images and you could zoom in more, but shooting just RAW means it uses the embedded JPG which isn't full size so you can't zoom in as much. That's the theory anyway--I'm a RAW-only guy.

 

[dhazeghi]

5x works for me. 7x and it starts looking like more than 100% zoom, but 5x - 7x is probably about right. 10x and it really starts looking wrong. Note that this is with an E-M5 shooting RAW. Maybe if shooting JPG or RAW+JPG it would use the full size JPG when reviewing images and you could zoom in more, but shooting just RAW means it uses the embedded JPG which isn't full size so you can't zoom in as much. That's the theory anyway--I'm a RAW-only guy.

Yes, if you want the best quality preview, you have to shoot LF JPEGs. Either in JPEG only mode, or in RAW+JPEG mode. That said, even with LF JPEGs, nothing looks good at 10x or higher. I suspect a better sharpening algorithm in the JPEG engine could make 10x useful, but that's something which is hard to upgrade.

 

[Jay86]

5x works for me. 7x and it starts looking like more than 100% zoom, but 5x - 7x is probably about right. 10x and it really starts looking wrong. Note that this is with an E-M5 shooting RAW. Maybe if shooting JPG or RAW+JPG it would use the full size JPG when reviewing images and you could zoom in more, but shooting just RAW means it uses the embedded JPG which isn't full size so you can't zoom in as much. That's the theory anyway--I'm a RAW-only guy.

Yes, if you want the best quality preview, you have to shoot LF JPEGs. Either in JPEG only mode, or in RAW+JPEG mode. That said, even with LF JPEGs, nothing looks good at 10x or higher. I suspect a better sharpening algorithm in the JPEG engine could make 10x useful, but that's something which is hard to upgrade.

^^^ Yah thats about where Im zooming into as well... 5-7x area on RAW. I guess I was in the ballpark then. Because 10x-14x looks bad on lcd screen.

 

[Zee]

I pray.

Z...

 

[laser8]

I pray.

Z...

Me too. I have been deceived so many times that until I see it on a proper screen, it's all wishes.

 

[Zee]

Yup, same. I've seen shots on the back LCD that look soft, and was shocked (in a good way) to see them tac sharp in Lightroom. And then, there is the more common reverse issue...

Looks great on the LCD, but then...

Z...

 

[drd1135]

I pray.

Z...

My very thought.

 

[christofp]

I have disabled instant review because the 1 second blackout/review would disturb me.

But I review quite often in the field when action is over. 5x or 7x magnification is roughly 100% or 1:1 pixel view.

You will not gain anything (unless you have bad eyes) if you go to 10x or 14x magnification.

 

[gr8Shot]

I don't - and sometimes I regret it.

The problem is: the LCD - magnified or not - does not help me enough to be sure. When I accidentally engage the @#$%^&* manual focusing clutch on my 12-40 lens, I am usually disappointed when I get home.

 

[Fmrvette]

How do you check critical focus and image sharpness "in the field"?

Like Gr8Shot, I don't.

I couldn't in the olden days of film and have never started the practice in the new age of digital.

Regards,

Jim

 

[jnewell]

The hardware and software issues don't give me any confidence that this is possible...so I don't try to check critical focus until I get back to a computer.

 

[Luckypenguin]

My Canon 50D and 500D both had high-res LCDs that allowed you to zoom in close to an image to check sharpness. I was somewhat disappointed with my first Micro 4/3 cameras (E-P1, GH1, E-PL1) that would allow you to zoom in up to a point but after that would just interpolate the image at the higher magnifications and not show any more detail. At least now my E-M5 and E-P5 let me zoom further in and still show detail. They're both sufficient to check an image in the field for sharpness, motion blur, and the point of focus. I've always shot full-res jpegs alongside raw files since they have a few practical advantages like this.

 

[DigitalD]

I'm on the fence. Some days I check some days not. Definitely more when shooting MF but I try to just check a few times at the beginning just so I can see that I'm capturing what focus I think I'm getting. A sort of self calibration and then I try to stop. 100% crop is my recko. Especially on the large EM5 and EM1 display. I also love the touchscreen for panning around to check oof areas as well

 

[dav1dz]

I wish that LCD was better, but they aren't. Zooming in and check faces really quickly usually does the trick but it's a pain in the ass. So I just hope the camera focused properly. Deep depth of field when in doubt! LOL

 

[Itchybiscuit]

I find it to be a balance - some shots look great but I've picked the wrong point of focus in shallow DoF, or sometimes I get a 2-fer when a framing reference appears to be on the same plane as the primary focus - I just didn't catch it initially at the point of capture.

This one illustrates my point with the blades of leaf helping things along:

Subscribe to see EXIF info for this image (if available)

 

[Bif]

I mostly do it as I shoot (time permitting). I have the button next to the PLAY button (AEL/AFL) set for autofocus and have the shutter autofocus set to OFF. I also set autofocus for SAF + MF ASSIST. So one button press does a quick autofocus and focus lock, turning the manual focus ring causes the magnified assist to "kick in" (usually set to 5 or 7) and I can quickly check focus or refine it and "nail" it. Touching the shutter button puts me back to normal view and I can take the picture.

I use the EVF for this, it has better resolution than the LCD.

My primary cameras are Panasonic (GH3 and GX7). The focus "lock" (allowing a return to manual focus) remains until the AEL/AFL button is pressed again. On the E-M5 I believe focus "lock" is released on taking the picture although the AEL/AFL button can be pressed at any time to refocus with AFS.

It took some practice to get it down and the extremely small button on the E-M5 didn't help but I keep it that way because it allows me the use of both autofocus and manual focus at will without having to change focus modes in a menu.

 

[Mike Wingate]

I use the Image app on my phone, pair with my camera, and check everything I can. If on a tripod, I control and take the shot using the phone.

 

[Mack]

In the field I use a large ultra-bright HDMI monitor. It has its own sharpening outlines separate from the camera, and being larger than the camera's small LCD also helps.

Aside, I was never a fan of the BBF method, but since I started using it my better focus hit rate gas gone up Maybe it's because the AF is then locked and using the shutter button AF causes it to go on a walk about and maybe not what I wanted it to lock on to begin with. AF seems to drift a bit so sometimes a second or third shot helps too.

 

[PakkyT]

What Im wondering here is what zoom level do you EM-5 folks (or any M43 shooters really) usually use to determine wether the image is likely sharp and critical focus has been achieved: 2x, 3x, 5x, 7x, 10x, 14x?

Like others here mentioned, I find the higher magnifications a bit unhelpful because when you zoom in a lot even sharp photos start to look soft. So I prefer lower magnifications like 5x-7x. But I also find, like @Bif mentioned, reviewing magnified images on the EVF much better than the back LCD especially outside on bright days.

However most of the time I don't bother. Instead I take advantage of it being digital and I can take all the photos I want for free. So assuming my subject is not something that is fleeting and I have the time, I will take 2 or 3 shots if I am doing something where I think nailing the focus may not be as simple as pressing the shutter button halfway and have DoF to get what I want in focus.

I also have an old habit from my dSLR days of "feathering" the shutter button several times when lining up my shot to make sure the AF is where it should be. Back in the phase detection days sometimes the focus could be a tiny bit off, especially if the focus had to move a long way to get to the spot and that second AF activation would be the one that would fine tune the final focus. Not really needed as much now with contrast AF but still a habit I stick with. Even with CAF I find the AF can be a bit fooled with certain subjects like flat signs or largely featureless things and you may not initially notice your AF spot in not right on a feature.