Focus issue.

roglowe

roglowe

Suspended / Banned
Messages
27
Name
Roger Lowe
Edit My Images
No
Whenever I take movement images in my studio, such as a child jumping, I can't seem to get a sharp focus!

Shooting at 1/160 shutter, Between f8 and f9. Nikon D80, Lencarta 300's.

I am shooting without tripod and without lens stabaliser.

If I increase the shutter to 1/200 i can see the shutter in the image, so I guess I can't shoot higher than 1/160.

Can anyone help with advice please how I can get sharper focus on movement under studio lights.

Thanks
 
Sounds like shutter speed is too low.

Are you using flash? with wireless triggers?
 
I am using lencarta elite 300 lights with wireless trigger.
when I up the SS to 1/200 you can see the shutter in the image.
 
The flash duration of the Lencarta ElitePro 300 is pretty short - but it may not be short enough for a jumping child, not many studio lights are.

The problem is not in fact the speed of movement as such, it's the direction of travel and the magnification - a F1 car travelling at 200 mph travelling towards the camera a long way away will create much less blur than a closeup of a jumping child, especially when the hands, hair etc are moving even more quickly than the body.

Another possible (likely) factor is the ambient light. If you have high levels of light in the room, for example daylight coming through the window, then there may be enough light to cause blur even if the flash itself is freezing the movement. The answer is to darken the room.

Nearly all radio triggers have a slight delay in firing, limiting the maximum shutter speed that can be used to less than that stated by the camera manufacturer, so direct connection by cable may allow you to use a slightly faster shutter speed - but this is unlikely to make a lot of difference.
 
To much ambient light?

The Lencarta 300's have a reasonably short flash duration that should be able to freeze motion well enough I would have thought. Set the 'film' speed lower so you can up the flash power, which in turn usually reduces the flash duration and will also reduce the effect of any ambient light present.

Also try a direct cable connection

Paul
 
I'm going to stop posting on these threads soon - I'm still being a Garry echo :lol: I guess I just type too slow...

Paul
 
paul williams said:
I'm going to stop posting on these threads soon - I'm still being a Garry echo :lol: I guess I just type too slow...

Paul
Click to expand...

:lol: They say that great minds think alike
 
Hi Paul,

what a fantastic video of dancers. She is so expressive and artistic and some wonderful shots by Alexander Heinrichs. I noticed that he was using the strip softboxes with diffusers! Just the same as we used in a group Lencarta Studio Lighting course on Sunday........ the're just great.

I would love to take such dramatic shots and it's made me think about dancers for a shoot soon.
 
Last edited:
alexam said:
Hi Paul,

what a fantastic video of dancers. She is so expressive and artistic and some wonderful shots by Alexander Heinrichs. Cris, did you notice that he was using the strip softboxes with diffusers! Just the same as us in the Lencarta Studio on Sunday........ the're just great. I would love to take such dramatic shots and it's made me think about dancers for a shoot soon.
Click to expand...

Alexander Heinrichs is one of my favourite photographers, he does wonderful studio work - unfortunately the only thing we share in common is the use of Multiblitz lighting. There are some great video's on his site unfortunately I don't speak German - checkout In bed with Franzy and enjoy the result with a pair of 200ws heads, which again features some stop motion.

Paul
 
Last edited:
As said, many studio lights have a duration that makes this tricky. I use Bowens 500R lights and I too have this problem for hands/fingers when kids jump as they tend to swing their arms up and to the sides (at 90deg to the direction of the lens which is obviously the worst scenario) like I say, it is normally just the extremities as the are moving the quickest, and if anything it helps the image with a sense of movement. My best advice is timing, if you can time your shutter release with the crest of the jump, their head is as still as it is going to be, so is sharp. Also experiment with your flash settings, some lights have a shorter duration at high power, others the opposite so iso and aperture can be combined to hit the optimum
 
There is one thing you can do - sounds tricky but it's actually very easy...
Use your studio lighting as you do now but add a hotshoe flash at something like 1/4 or less power. Turning down the power on a hotshoe flash will produce a brief flash duration that will probably give you an underlying sharp image.

Of course, the low power of the hotshoe flash will mean that you need to turn down the power of your studio flashes for the hotshoe flash to make a worthwhile contribution, this will INCREASE the flash duration, which is the opposite of what you need to do if relying on the studio flashes alone.

So, you'll get more blur but with an underlying sharp image - worth trying!
 
Thanks for that Paul, another great video with some wonderful shots of Franzy.
I particularly liked the one throwing the pillow. Top rate glamour without the 'smut'! seen elsewhere....................... a goal to achieve.
 
Everything Garry and Paul said about the flash duration is correct. But OP said he can't get sharp "focus", and didn't mention motion blur. In my experience, just to capture basic child jump type shot, flash duration won't cause a drunken blurry shots. Hands or bit of hair might have motion blur, but face/most of body is pretty fixed, although I sync at 250th rather than 160th.

I wonder if it's the focusing technique that's the issue here. For action shots, i would pre-focus and shoot. Could be a simple camera setting.

Assign focus to AF-L button only.
Shutter release button to simply take the shots.
AF-C
Get the subject to stay still for a second while you pre focus using AF-L button.

Then, ACTION.

Maybe?
 
hairboy said:
Everything Garry and Paul said about the flash duration is correct. But OP said he can't get sharp "focus", and didn't mention motion blur. In my experience, just to capture basic child jump type shot, flash duration won't cause a drunken blurry shots. Hands or bit of hair might have motion blur, but face/most of body is pretty fixed, although I sync at 250th rather than 160th.

I wonder if it's the focusing technique that's the issue here. For action shots, i would pre-focus and shoot. Could be a simple camera setting.

Assign focus to AF-L button only.
Shutter release button to simply take the shots.
AF-C
Get the subject to stay still for a second while you pre focus using AF-L button.

Then, ACTION.

Maybe?
Click to expand...
Good point, that could be the cause of the problem
 
I think it might be a focus issue too. Post a picture for a conclusive answer.

Depth of field is often less than you think, and kids especially move around after you've focused. Flash durations can be a problem with studio heads, but they're usually fast enough. As mentioned above, hands and feet bluring is usually okay, it's faces that must be sharp.

Suggest powering up the flash a bit, shooting at f/11, and keeping a careful eye on focusing.
 
Thanks for the replies.

Here is an example. The model had flicked her head toward the camera so as to make her hair flow. Her hair seems Out of focus... I can't seem to get the whole shot in focus with the motion blur.

http://www.flickr.com/photos/44948624@N06/5613550902/

Nikon D80 - 1/160s / F9 / 50mm lens.
 
Last edited:
roglowe said:
Thanks for the replies.

Here is an example. The model had flicked her head toward the camera so as to make her hair flow. Her hair seems Out of focus... I can't seem to get the whole shot in focus with the motion blur.

http://www.flickr.com/photos/44948624@N06/5613550902/

Nikon D80 - 1/160s / F9 / 50mm lens.
Click to expand...

That's just a bit a motion blur on the tips of the hair. You'll struggle to do much about it.

Garry's idea might reduce the appearance a bit by overlaying a sharp image over the blurred element, but it would be a bit of a palava to get that right, without the hot-shoe gun casting its own light on to the subject.

Personally, I don't have a problem with it. Nice shot :)

If you do a lot of work like that, and it's important, you need to get studio heads with significantly shorter flash duration. They're around, designed mainly for that kind of application. Be aware that quoted flash durations (ie t0.5 etc, and there's not much info published about this kind of thing) do not always translate into action-stopping potential, and in my (limited) experiece testing these things, a quoted duration of say 1/1000sec does not give anything like the stopping power of 1/1000sec shutter speed or what you would get from a hot-shoe gun at that quoted flash duration. The nature of the actual flash pulse is different.

Just thinking about it, if you could work a hot-shoe gun into it as the main light, replacing the studio head completely, and shoot at half power or less, that would stop everything dead. That would be around a 'real' 1/2000sec. Quarter power 1/4000sec and so on. Might be the easiest way for occasions when you need it.
 
Last edited:
Richard is right. This is a movement blur 'problem' that in my view doesn't really exist, it isn't any kind of focusing issue.
A nice shot apart from the lighting IMO... A single light would have produced modelling on the face, but of course that's your choice.

BTW, the method I suggested of using a hotshoe flash in conjunction with studio flash (when I assumed that the blur was serious) is something that's used a lot in fashion photography and well worth trying out. It's normally done by using studio flash heads that have fairly long flash durations (by turning the power down) to deliberately produce some subject blur, and using a hotshoe flash to get that sharp underlying image I mentioned - very effective when there's a lot of subject movement that needs to be shown.
 
Garry Edwards said:
Richard is right. This is a movement blur 'problem' that in my view doesn't really exist, it isn't any kind of focusing issue.
A nice shot apart from the lighting IMO... A single light would have produced modelling on the face, but of course that's your choice.

BTW, the method I suggested of using a hotshoe flash in conjunction with studio flash (when I assumed that the blur was serious) is something that's used a lot in fashion photography and well worth trying out. It's normally done by using studio flash heads that have fairly long flash durations (by turning the power down) to deliberately produce some subject blur, and using a hotshoe flash to get that sharp underlying image I mentioned - very effective when there's a lot of subject movement that needs to be shown.
Click to expand...



Just had a look at that pic, looks like you nailed the focus to me. The ends of the models hair will be moving pretty fast, without that bit of motion blur it wouldn't look natural IMO. Nice shot.
 
Just took a look at the pic. Looks fine to me. Focusing isn't the issue. It was motion blur. I prefer the shot with a little movement. Bring a shot alive. I wouldn't call it a problem. But if you want to really freeze every strand of hair, you need the likes of Bowen Quad X for the fast flash duration. But you are looking at £3k plus, and for portraiture, it really ain't worth it, IMO. If you were shooting, say, dance or sports photography, things would be different.

If you use speedlights, you can get the flash duration, but you'd need to have the flash very close to the subject, and must set the power at 1/2 or lower for the fast duration.

So it's always a trade off between the speed, power and costs. Personally, I'd live with the blurry hair - call it creative. That's what I do :-)
 
Thanks for the help guys.
 
paul williams said:
To much ambient light?

The Lencarta 300's have a reasonably short flash duration that should be able to freeze motion well enough I would have thought. Set the 'film' speed lower so you can up the flash power, which in turn usually reduces the flash duration and will also reduce the effect of any ambient light present.

Also try a direct cable connection

Paul
Click to expand...

I have a Canon 7D now and it has a sync lead socket. I connected the sync lead and got perfect focus. After all this I did not realise the remote trigger has a battery in it. I checked the battery on a tester and it is basically dead!! So I think I need a brand new battery in the remote trigger.... :bang:
At least there is nothing wrong with my manual setting choice or wobble arms...
 
You must log in or register to reply here.
Back
Top