How do I make a propeller look like it's spinning?

Hi all

I have a real problem with this and seem to be banging my head against a brick wall.

Generally, I can get a little movement in the props of flying aircraft, but I have one shot in particular of a Spitfire 'gatekeeper' that is in a static display. I've highly edited the shot to remove buildings, cables and a support pole to make the aircraft look as though it is in flight, but the prop is static and I cant find how to add a little radial blur to the visible parts of the prop.

I do have GIMP, but can't work out how to use the radial tool to good effect. Is anyone able to help with an 'idiots guide'?

Many thanks
Mike

The answer to your thread title question is, "It depends." Lets do the math...

You're ahead by realizing that the more esthetically pleasing photos of propeller-driven airplanes show the prop as a complete disk. At a typical cruise speed, the prop is turning at about 2,400 RPM. (It might be higher or lower, but 2,400 makes the math easy.) 2,400 revolutions per minute is 40 revolutions per second. So, to get the shot with the complete prop disk - i.e., each blade making one revolution during the shutter exposure - you'd need to have the shutter set for less than or equal to 1/40 second.

Can you see why the pros shooting air-to-air use the expensive stabilization gyro attachments?

However, you can get a shot that's almost as good if the prop blades together make up one full rotation while the shutter is open. A two-bladed prop will cover the full disk of motion in half the time it takes each blade to make a full revolution. Now, we're up to 1/80 second. A three-bladed prop = 1/120 second.

Finally, if the airplane is landing, the prop may only be turning 1,200 RPM. A full disk for each blade = 1/20 second; 2-blade = 1/40 and 3-blade = 1/60.

The bottom line is set shutter-priority and you may have to use an ND filter on a bright, sunny day.

Good luck and stay out of the prop arc - it's a killer.

I read this as you want to photoshop propeller movement...If this is the case could you post the shot and I'll have a go..

pedroj said:

I read this as you want to photoshop propeller movement...If this is the case could you post the shot and I'll have a go..

Click to expand...

Thanks for the reply PhotoAV8R, but pedroj is correct, it's the photoshop I need to know how to do (the information you posted is still useful though!)

Here's the pic in question


All I want to do is get some movement in the prop
Many thanks
Mike

I found this: Photoshop Radial Blur filter

Not sure it will help since your picture is from behind. I am thinking you need to take a head on shot. But i know nout about Photoshop.

This a quick go at it...I selected the elliptical marque tool tool then formed a circle, then selected radial blur strength 11
then placed a copy of the original over top then rubbed out the bits to form the blur... Not the best but with a bit of care and patience you could get it pretty good..Here's the result..

AC016 said:

I found this: Photoshop Radial Blur filter

Not sure it will help since your picture is from behind. I am thinking you need to take a head on shot. But i know nout about Photoshop.

Click to expand...

I see what you mean about 'head on'. I don't think that would work on the shot, unless there was a way to isolate or erase certain areas. I don't have Photoshop, although I'd probably get it if it did what I wanted! (I do have GIMP and believe it may do what I want, but haven't got a clue how to do it!)

pedroj said:

This a quick go at it...I selected the elliptical marque tool tool then formed a circle, then selected radial blur strength 11
then placed a copy of the original over top then rubbed out the bits to form the blur... Not the best but with a bit of care and patience you could get it pretty good..Here's the result..

Click to expand...

I like the idea. What programme is it in?
I'm still hoping someone can find a way of doing it in GIMP as I do have that.

Someone did this for me:


It was through a photo section of an MG Car forum. I understand it was done with GIMP. The problem is, it was done by a 'friend of a friend' and I can't make contact with the person who organised it, so I could find out how it was done. It's clearly a partial radial blur with erasing facility.

All I want is to find out how it's done!

Mine was done in Photoshop CS5

I spent a bit more time on it this time...