depth of field blur

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My point-and-shoot IXUS 86'IS doesn't really allow for blurring backgrounds like you can with a manual camera. I thought there would be a blurring tool in Lightroom to simulate the effect of depth of field blur, but I can only find the sharpness and clarity settings in the Adjustment Brush tool - they are too subtle and don't blur enough.

Any suggestions?
Thanks.
 
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Re: focal length blur

Keep doing it. Create a new brush, and re-apply negative clarity and sharpness over the previous. Repeat 'til satisfied. If not satisfied, you're going to have to go to PS or similar.....
 
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Re: focal length blur

> Keep doing it. Create a new brush, and re-apply negative clarity and
> sharpness over the previous. Repeat 'til satisfied

I'm not sure I'm doing this right...
I paint the background area, and click 'new', paint it, click 'new', etc?
I did that about 3' times but the background didn't blur any more
than the first time at 1''% flow and density.

Is 'auto mask' supposed to be on or off?

It's a pity if we have to export photos to another program just to do blur.
I suppose that's what you get when all the developers and beta testers
all use fancy cameras! :D
 
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Re: focal length blur

[quote author=Anti link=topic=7328.msg49955#msg49955 date=124848'979]It's a pity if we have to export photos to another program just to do blur.[/quote] Lightroom does ~9'% of the photographer's needs. It does not do layers or a lot of other fancy photo gimics. Lightroom provides a link to external programs just to cover the other 1'%. If Lightroom did everything, then there would be no need to spend close to $2k on Photoshop CS.
 
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Re: focal length blur

Thanks for confirming this kind of tool isn't available.

> It does not do layers or a lot of other fancy photo gimics

Of course, you're right. Priorities have to be carefully chosen. However, it's entirely possible that one person's 'useful feature' is another person's gimic. I was just somewhat jokingly alluding to a possible reason why a blur tool didn't make it into the developer's list of priorities. Perhaps you can suggest a more founded reason why Lightbox doesn't have gausian and/or movement blur?

For the 'general masses' using compact cameras, adding a blur setting on the adjustment brush would have been quite an easy, unobtrusive, useful feature I'd have thought, for those that can't do it in the camera.
 
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Re: focal length blur

Sorry, for me to chime in late but that is what happens when I work full time.

Blurring is a function of depth of field(area in focus). Yes, focal length does have an effect. I know that my 6''mm/f4 has shallower depth of field vs the 16mm fisheye. But, aperture has more pronounce effect on depth of field. The bigger the aperture( smaller the number) causes the depth of field to be very narrow thus you get blurring.
So, I went on line to see the spec of your camera( IXUS 86'is) which has zoom range of 28-1'5 with 17 shooting modes. I suggest that you shoot at 1'5mm on portrait mode. Portrait mode will tell the camera to "open up" the aperture thus causing your depth of field to be more narrow thus you get some type of blurrring effect. I hope this helps.

Bob- the slide shooter at heart
 
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> Blurring is a function of depth of field.

Ah, that's the phrase I was looking for - simulate a shallow depth of field.
I've changed my post and title accordingly.

Thanks very much for checking out my camera. I've tried what you described, but whenever I use the zoom at 3.8x or more, the aperture is set to the maximum value of f/5.8. Also 'portrait mode' doesn't seem to have any affect on aperture - it just warms skin tone and uses face recognition for focusing.

No matter what I do, I can't get a shallow depth of field with this point-and-shoot. I can get the background very slightly blurred, but nowhere near like the effect used by manual SLR owners.

I suppose I'll have to export to a fully-fledged editor - there are many free ones out there.
I'll only have to do it a couple of dozen times during a year anyway, I think.
EDIT:
Or I could buy this plugin for 16'$.
http://www.ononesoftware.com/detail.php?prodLine_id=35
Ouch, my wallet hurts even just thinking about it!

Cheers.
 
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The blur related to depth of field cannot be fully simulated in post-processing, at least not without an enormous amount of work. That's because the amount of blur varies with the distance from the focal plane, and there's no way for post-processing software to know how far everything was from the focal plane.

This is just one of those tradeoffs between small-sensor cameras and large-sensor cameras. If you want a shallow depth of field, you need a larger sensor. If you want great depth of field (often very helpful in macro shots, for example) you want a smaller sensor.
 
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I also have an IXUS 86' IS, and it's actual focal length is 4,6-17,3 mm as stated on the front of the lens. Since the IXUS have a very small sensor (~36 times smaller than a full-frame 24*36 mm sensor) that zoom-range corresponds angle-wise to 28-1'5 mm on a full-frame camera, such as my Nikon D7''. That is the famous crop-factor. My D7'' has a 24-7' mm zoom, and since it is full-frame there is no crop-factor involved.

DOF (depth-of-field) depends on focal length, aperture and distance camera-to-subject. Another way of putting it is it depends on aperture and magnification scale.

If you and you subject stay in the same place, but you zoom to different focal lengths, and keep the same aperture, a longer focal length gives shorter DOF. But you also get completely different images: the more you zoom the less of the subject you capture.

If you keep your aperture the same, but move yourself and then zoom so that the subject is always equally large in the resulting image, the DOF is the same!

And then compact IXUS versus big DSLR: when you use your 1'5 mm zoom-position, it is actually only 17,3 mm. On my D7'', 1'5 mm is 1'5 mm. 17,3 mm gives huge DOF.

Two links for more info:

http://www.dofmaster.com/dofjs.html
www.tawbaware.com/maxlyons/calc.htm
 
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You can one more thing. Your camera has variable aperture which changes as you zoom. That is why you had an aperture of 5.8 when you zoomed out to 1'5mm.
As Robert(Erro) has mentioned that your camera has a small sensor( I forgot about that- you are dealing with a film person) so you are stuck. No matter what you do with your camera- you cannot get any blurring.

Bob- the slide shooter at heart

PS: Anti- you may consider getting another camera; maybe with a full frame sensor.
 
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