Movement & Motion Blur

[Tai]

Ok so I know by using a neutral density filter you can lower you shutter speed as low as you like while keeping your aperture at a resonable level of around f/22.

I know that this will achieve motion blur and I know it works great when photographing water.

But I'm not sure if it will work in the situation I want to use it for. I will be using a 20mm wide angle lens to photograph a model in a busy city and I want a lot of movement and some motion blur in the background but I want the model to stay relatively sharp as the shoot is more about what she is wearing more than anything else.

If I use this technique of lowering the shutter speed and adding the ND filter will it work? Can someone just tell me if it will work or if I am completely wrong and should keep thinking. THANKS!

[livio]

Hmm it will depend on how much light there is if it is in the middle of the day you can do this with an ND filter and f/22 to get a slower shutter speed
you can also do this via setting a lower ISO. If it is going to be a little darker you can use an offset flash for the model and leave the shutter open a little more for the movement in the surrounding area. Just ned to make sure you are on a good tripod in fact the flash could be fired manually if the model does not stay still though you may still see some motion blur.

[William]

First ,f22 IMO is extreme, You can get motion blur behind the model , Just get her to stand still and not move for at least 1/6th or 1/8th of a sec

[ricktas]

You could also try using second sync flash.

Getting the model to stand perfectly still during a longer exposure is going to be your hardest aspect of this shoot.

[ameerat42]

Also, f/22 on such a wide lens is almost pinhole. Your depth-of-field will extend from sub-atomic particle to the edge of the universe (as we know it). A flash fired in such circumstances would effectively freeze everything within its effective illumination range. I'm thinking that after you fired any flash to light the model - at a wider f-stop - a few seconds more of stillness should suffice.
Am.

[jjphoto]

You will be surprised how hard it is for a person to stay very still for an extended period, eg 5-30 sec. Not saying it can't be done but I am saying it can't be done with the subject still enough for a really sharp image of them (which might not matter to you anyway).

Don't shoot at F22 if you can avoid it. Your images will be soft compared to approx F5-6-11. Dust will also be far more obvious. Use whatever ND filter you need to get the shutter speed you want but try to resist stopping down too much. Image quality will suffer.

JJ

[dieselpower]

Sounds like you're doing a Photography Institute course. I had the exact same question.

You're on the right track - to create movement you need to slow the shutter speed. If you're in broad daylight in middle of the day then f/22, ISO 100 should do it without an ND filter however as suggested, everything will be in focus at f/22 on a wide angle lens and most likely it will be very soft. I'd suggest perhaps f/8 or f/11 would be more appropriate. You'll still need to slow the shutter down then without stopping the lens down any further. This is where ISO and ND filters will come in handy.

[Brian500au]

Ok do you want motion blur or depth of field? Motion blur is relative to how fast the subject is moving. If the back ground is a moving car then you can stop the model with a strobe and 1/30 second shutter speed but anything moving in the back ground will have some motion blur. If you want the model to stand out and blur the back ground then you want to concentrate on brokeh. It all depends on what you want to achieve.

You can also do a composite image.

[William W]

Ok so I know by using a neutral density filter you can lower you shutter speed as low as you like while keeping your aperture at a resonable level of around f/22.

I know that this will achieve motion blur and I know it works great when photographing water.

But I'm not sure if it will work in the situation I want to use it for. I will be using a 20mm wide angle lens to photograph a model in a busy city and I want a lot of movement and some motion blur in the background but I want the model to stay relatively sharp as the shoot is more about what she is wearing more than anything else.

If I use this technique of lowering the shutter speed and adding the ND filter will it work? Can someone just tell me if it will work or if I am completely wrong and should keep thinking. THANKS!

If you can choose the time and the place in the city, you probably do not need a ND filter.
If you are allowed to use Flash then it is easy.
If both the above are possible - this exercise / exam question can be approached as a Flash Fill question – and you should be thinking along those lines to get the best results.

If it is not an exam question and you want the precise answer then ask – if it is an exam question or course work, then go and work it out from those hints.

WW

[Mark L]

And post some images from your first attempt.
I'll bet the feedback you get from them will help make your second attempt about what you want.

[ricktas]

The OP has not been back since one minute after posting his question. Hopefully he will come back and at least thank everyone, and let us know how he went, or how he has decided to proceed with the shoot.

[jjphoto]

... Hopefully he will come back and at least thank everyone, ....

Oh. I'm sure he'll be back to think people. It would be rude not to, don't you think?

JJ

[Allan Ryan]

its probably cheating But
how about 2 shots on a tripod

1 for model to get the detail
1 for background
and open them in PS as layers
then bend as required.