Depth of Field Question - Newbie

[BeerBelly]

Hi, only just starting to understand all the components that make up an exposure.

Real quick DOF question.

Trying to be clever and shot a matchbox car close to make it as big as a real car in the background. Obviously I can focus on background or foreground - is there a way I can trick the focus to a happy medium so the toy car looks the same size as the real car and make them both a similar focus? Do I have to focus in on something that is in between the toy car and real car to achieve this - haven;t got a clue!

Its for a fun work contest and apart from cropping no editing is allowed. Using a Canon 450D and pretty much shooting in auto mode until I've read some more books and experimented (only had a few weeks). Any help or tips would be appreciated! Can upload some efforts if you need to see what I mean?

[beejaybee]

Trying to be clever and shot a matchbox car close to make it as big as a real car in the background. Obviously I can focus on background or foreground - is there a way I can trick the focus to a happy medium so the toy car looks the same size as the real car and make them both a similar focus? Do I have to focus in on something that is in between the toy car and real car to achieve this

I think you'll struggle with anything other than a phone cam, unless you use a pinhole "lens" (which doesn't need focusing at all).

Focus on something twice as far away as the closest point you want in focus in order to get the optimum DoF.

[LargeFormat]

That's one of the reasons people use large frame cameras with tilt lens and back. You can achieve focus at different distances across the picture so, say, the bottom of the frame can be in focus on something close and the top on infinity. If large format is going a bit too far Canon and Nikon make tilt/shift lenses for their cameras and Hartblie (using Carl Zeiss optics) make them for a number of mounts.

[alanS]

How about as wide a lens as possible with a small aperture, hyperfocal style. The DOF should be quite deep.

[Per]

Or borrow a TSE 24 lens and use shift to swing the focal plane into a focal wedge (and stop down to f/22), a bit like the aforementioned large format camera.

Actually, I have one of these lenses so I'll try it out - sounds fun!

[El_Sid]

If you have a Cokin filter mount you could try one of the Cokin Split Close-Up filters (Ref Nos. 111-113, scroll down page)...

[AlexMonro]

Or borrow a TSE 24 lens and use shift to swing the focal plane into a focal wedge (and stop down to f/22), a bit like the aforementioned large format camera.

Actually, I have one of these lenses so I'll try it out - sounds fun!

I think that's tilt you use to swing the focal plane - it's still a plane, but no longer parrallel to the film / sensor plane, though I guess it makes the DoF "sharp" zone into a wedge.

Something I'd like to play with sometime - when I can afford a TSE or a large format camera with movements - or maybe a Hartblei?

Can I say "Shiempflug Rule"? And more to the point, can I spell it?

[LargeFormat]

If you have a Cokin filter mount you could try one of the Cokin Split Close-Up filters (Ref Nos. 111-113, scroll down page)...

Good idea, I'd forgotten about them. You can also get circular screw in versions bit like polarising filters.

[Garry McNamara]

You could try taking several pictures at different focus settings and combining them in a program like Helicon Focus which combines the sharpest element from several pictures - the more the merrier.

[Zou]

You could try taking several pictures at different focus settings and combining them in a program like Helicon Focus which combines the sharpest element from several pictures - the more the merrier.

Am I the only person who sees that and thinks - why bother? 1st shot is at f8 - hardly pushing the boat out - and the second shot isn't exactly a resounding victory - still got bits out of focus.

A really low-tech alternative would be to shoot from a greater distance with a smaller aperture (making sure the whole scene is sharp) and crop to the scene intended...

[Garry McNamara]

Your right, it is a subtle difference and personally I don't like the look of the sharp areas. Of course since the requirements of the brief say no editing it couldn't be used anyway. There are times when it can be used effectively but they are few and far between - at extreme close up it turns your camera into a kind of scanning microscope.

[daft_biker]

You could try taking several pictures at different focus settings and combining them in a program like Helicon Focus which combines the sharpest element from several pictures - the more the merrier.

Thanks Garry, haven't tried that program. Will give it a go and see if it's any better than CombineZM (since I'm too lazy to do stacking properly in photoshop....but then that would be editing ).

[Baz94]

Personally, I would se the camera in place and have the focus on the small car and then CLICK, then without moving a fraction, focus on the 2nd car and then click then use elements 4 (Thats what I have) to merge them together or whatever pragram has a cloning tool :-)

[Monobod]

Try this website:

HERE

[starside]

If you have a Cokin filter mount you could try one of the Cokin Split Close-Up filters (Ref Nos. 111-113, scroll down page)...

using a split field focus filter is the only way of doing it.

see here fo use of this filter: http://www.shutterbug.com/features/0...lit/index.html