UKH

I'd appreciate any tips or advice on how to get pin-sharp focusing on fast moving subjects which are either moving parallel to you or are barrelling towards the camera.

Cheers muchly

In reply to The Lemming: what camera?

In reply to The Lemming:

You are using continuous AF for these objects, aren't you ?

In reply to IPPurewater:


I was just looking for tips for stuff too fast for my auto focus to keep up with. Also my Auto Focus is quite complex with lots of ways to focus and I want to simplify the whole process.

Later, this year I'm going to try and photograph my mate on his road bike in various locations, including when he's in a pack. I want him pin-sharp while also conveying motion blur for all the stuff around him.

I'm also after that illusive shot of my small black dog running around like a looney. Still haven't got a pin-sharp image. Either the mid body is in focus or the background is in focus but not the head. I'm guessing that the camera is focusing on the contrast between the bright yellow harness and the black fur, rather than the head. Even with an f8 I can't get a sharp image.

In reply to The Lemming:

OK. Really the only thing I can think of then, is to prefocus on a point that you know your friend will cycle through and hold that focal distance, while panning. My Olly has a focus lock. That is what I use.

In reply to The Lemming:
Don't forget that perceived 'sharpness' is a combination of focus and camera movement. You can reduce the latter considerably by using a tripod. So for your cycling shots set up and preview some test pictures on the tripod ready for the real passing by. BTW I use a system that has vibration reduction which helps in many situations but it is better to use a solid base - tripod - and switch VR off for improved 'sharpness'.

In reply to The Lemming:

Google "setting up GH4 for sports"; click on the Video Tab, listen to some Americans.

In reply to The Lemming:

Perhaps a silly question (from me, not you!), but are you using the pinpoint focus mode?

In reply to ChrisJD:

Their voice gets on my tits.



But I am watching a few of them.

In reply to ChrisJD:


The camera has a couple of gimmicks that I think I will play with tomorrow, one of which is to take a photo and then look at it after its taken and choose where to focus.

Sounds like witchcraft to me.

In reply to The Lemming:



Ahem.

In reply to Fraser:

Yawn

In reply to The Lemming:



I can think of a number of way this could be done - ranging from promising to rubbish:
1. Camera takes a rapid sequence of exposures whiles shifting the focus slightly through the selected focus point. Haven't heard of this being used, but some older cameras used to do something similar to combat shake (pre-stabilisation). Sort of high-speed 'focus stacking'.
2. Software can try an 'guess' what the in-focus image was from the blurred version (aka convolution filters), but this is pretty limited and tends to create artifacts. I've used it to compensate for slight miss-tracking on astrophotos.
3. Software blurs the bits you don't want in focus, which makes the 'in-focus' bit appear sharper. Yuck.

In reply to The Lemming:

Use a smaller aperture?

Or a light field camera? (these truly are witchcraft and I've no idea if they are really what you want).
https://pictures.lytro.com

In reply to The Lemming:
Use multishot mode and fix the focal distance? 2nd curtain flash? It should be relatively easy to get a subject moving across your FoV which isn't moving closer or further away and that's just a case of setting the focal distance and perfecting your panning technique.
For something moving toward you at speed I find multishot with fixed focus the best option as C-AF simply isn't good enough on the E-M5 (and may not be on the GH4 either)

If you have the option of 2nd curtain flash then that should allow you to get trails with a sharp subject- you can use a 'long' shutter to allow trails but the flash will freeze the subject and expose it more at the end of the process.

Caveat - I don't do much of this at all, and am nowhere near mastering flash exposure.

In reply to Marek:



That's exactly what the camera does, and hand held too. You choose the aperture and the subject matter then press the shutter. The camera then individually focuses on each of the 49 focus points and fires off a shot. The witch-craft comes when you review the image on the screen. Press one area and the image focuses on that point. Point onto another part of the screen and the image focuses on that position.

Awsome and works perfectly. The only problem, and its not a problem really, is that the images caprured are JPEGS rather than RAW.

The camera takes 4K stills in a similar way but is more for stuff moving around rather than a still-life shot. You take a 4K movie of what ever is happening in front of you. After that, you review the images and select the one you want. Its an in-camera screen shot of what you have just taken. This gave me mixed results, and to be honest I much prefer the fast burst rate of a shot taken at x-thousandths of a second.

Still got to work out how to focus on a small black dog running as stupid miles per hour.

In reply to MeMeMe:



That's what my camera does. I'm beginning to realise the potential and benefits of a mirror-less camera system now.

In reply to The Lemming:

for fast(er) moving subjects on my mirror-less (a6000) i use a couple of techniques depending on the situation

tracking works reasonable well but my normal method is to set a button for "back button focusing", set the continuous focus drive option, move the flexible focus spot to the general area the part i want the focus on is going to be (face for example)

line the focus square up with the face, press and hold the back focus button to continually focus on that point and then press the shutter button when i want to shoot (with multiple fps if you like) keep panning etc to hold the focus point on the focus target

by separating the focus control from the shutter release it keeps focusing while to take each image.

youtube back button focusing for a general discussion on this and then add you GH4 to the end to see how to set it up on your camera... and practice practice practice

In reply to rallymania:

I've seen a few back button vids over the last few weeks. I'll give it a try today.

Cheers

In reply to The Lemming:

I've been using it a while, it does take practice, stick with it... and you have to instruct people when you hand your camera over to them lol

i think the top end canon / nikon pro DSLR's have an extra button on the back so you don't need to assign a different button. on my sony i use the exposure lock button as it has a ridge round it so you know by feel you are pressing the correct button with your thumb.

In reply to The Lemming:

Pre-focus at required distance then blast the shutter.

In reply to The Lemming:


What you got?

Has it got a Trap Focus option?

In reply to rallymania:





I given the back button technique a go for a couple of outings and I have to say that I am still getting blurry shots. However the percentage of sharp images is improving. And today, with the sunshine and a fast shutter, I got a few good shots of Bailey running around like a Looney.

In reply to The Lemming:

I think I have this focusing and fast moving subjects nailed. Well at least trying to photograph a tiny black dog barrelling towards the camera.

I think my problem was having too wide a focal length for such a wee beastie as my dog to begin with. By the time my tiny dog filled up the frame of my 35mm lens, that's 70mm on a full-frame equivalent, the camera had trouble focusing on him before he'd shot past my camera.

Having a longer zoom range as well as using the back-button focusing has solved that problem. Yes, I get shed loads of out of focus images but when I hit that magical moment, I'm more than happy with the results.

https://www.flickr.com/photos/the1lemming/32705938826/in/dateposted-public/

Cheers all