Question for full frame shooters

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Archive 2009 · Question for full frame shooters

huguito
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p.1 #1 · Question for full frame shooters

I am considering going from a 20D to a bigger frame option, full or the 1.3. maybe a used 5D or a 1D.

Besides the obvious gain on better image quality, will I see a great deal of improvement on the quality of bokeh in out of focus area shooting wide open?

Anybody has samples of the same lens, wide open, or close to wide open, shooting with a 1,6 sensor like a 20D, 30D or 40D, against full or 1,3frame?

Thanks for the help

Hugo

Jul 09, 2009 at 05:16 PM

nathanlake
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p.1 #2 · Question for full frame shooters

This is going to start a huge discussion, so I will step in first.

The sensor itself does not impact the bokeh EXCEPT by dictating how far away you are from the subject to get the framing that you want.

BOKEH is primarily a function of the lens.

Jul 09, 2009 at 05:24 PM

huguito
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p.1 #3 · Question for full frame shooters

HI Nathan
So you say that if I fill the frame the same way. With my 20D and with a regular 5D.
Using the same 24-70.
Lets say a face touching the edges up and down, shooting open to 2.8, the out of focus background will look the same ?
That was my question

Hugo

Jul 09, 2009 at 05:29 PM

Lovesong
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p.1 #4 · Question for full frame shooters

You are inherently going to be closer to your subject with the FF in that scenario, so your DOF will be shallower.

Jul 09, 2009 at 05:31 PM

Zara
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p.1 #5 · Question for full frame shooters

There was a recent discussion which had some good comparisons posted. I'm pretty sure it will provide you with most of your answers: http://www.fredmiranda.com/forum/topic/781852/

Jul 09, 2009 at 05:32 PM

Ian.Dobinson
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p.1 #6 · Question for full frame shooters

OK the 3 paramaters that control DOF and also the resultant bokeh.
Distance to subject and or backround
Focal length of the lense
Apature of the lens

Now to fill the frame equally between FF and crop you have to change 1 of the first 2 so you will change the resultant image.
You will either have to move closer to the subject or use a longer focal length.
As you do either of these the effective appature (as far as DOF is concerened will be the amount of crop (1.6 or 1.3) stops better/wider

Edited on Jul 09, 2009 at 05:36 PM · View previous versions

Jul 09, 2009 at 05:34 PM

nathanlake
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p.1 #7 · Question for full frame shooters

huguito wrote:
HI Nathan
So you say that if I fill the frame the same way. With my 20D and with a regular 5D.
Using the same 24-70.
Lets say a face touching the edges up and down, shooting open to 2.8, the out of focus background will look the same ?
That was my question

Hugo

No...if you fill the frame the same way, you will be closer with the 5D than you would be with the 20D. That difference in distance will impact the DOF.

Jul 09, 2009 at 05:35 PM

omarlyn
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p.1 #8 · Question for full frame shooters

huguito wrote:
HI Nathan
So you say that if I fill the frame the same way. With my 20D and with a regular 5D.
Using the same 24-70.
Lets say a face touching the edges up and down, shooting open to 2.8, the out of focus background will look the same ?
That was my question

Hugo

If you fill the frame the same way, your subject distance will be different and as a result of the different subject distance ratio, this will effect the appearance of the bokah. Nathan is right...this will instigate alot of argueing back & forth.

HTH,

Omar

Jul 09, 2009 at 05:36 PM

thedigitalbean
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p.1 #9 · Question for full frame shooters

I'm going to chime in on the usage of the term 'bokeh'. Bokeh refers ONLY to the aesthetic QUALITY of out of focus light sources. I.e. its a term to describe the quality and NOT the amount of background blur. Hence its a property only of the lens.

Jul 09, 2009 at 05:38 PM

Zara
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p.1 #10 · Question for full frame shooters

As Nathan said, the quality of the background blur (bokeh) is a feature of the lens design and will not change with the sensor size. But as others are pointing out (and as was discussed and demonstrated at length in the thread I referenced) in many shooting situations you can and do achieve a larger quantity of background blur (often mistakenly referred to as bokeh) with a larger sensor.

Edit: I see thedigitalbean has beat me to it

Jul 09, 2009 at 05:40 PM

nathanlake
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p.1 #11 · Question for full frame shooters

If we discuss the quality of the bokeh, you also need to look at the number of aperture blades. Most photogs seems to prefer that OOF lights have a round appearance. The more blades you have, the closer you get to round.

Jul 09, 2009 at 05:43 PM

huguito
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p.1 #12 · Question for full frame shooters

Thanks everyone. I was not very clear in my question.
i was not asking about quantity of bokeh, I understand the relation between distance from subject and out of focus plane.
O was more interested in the very hard to define "Quality or Creaminess" of the out of focus area using the same level of glass.
Hugo

Jul 09, 2009 at 05:44 PM

Zara
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p.1 #13 · Question for full frame shooters

huguito wrote:
Thanks everyone. I was not very clear in my question.
i was not asking about quantity of bokeh, I understand the relation between distance from subject and out of focus plane.
O was more interested in the very hard to define "Quality or Creaminess" of the out of focus area using the same level of glass.
Hugo

Of course the "creaminess" increases with the amount of blur that you have - which is potentially higher with a larger sensor.

But the overall quality of this blur is not changed by the sensor. If a lens provides you with nisen type bokeh on an APS-C sensor, then it will still do the same on a FF sensor.

Jul 09, 2009 at 05:53 PM

Ian.Dobinson
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p.1 #14 · Question for full frame shooters

well the quality could increase as if your closer to the subject or use a longer focal length you will diffuse the background more (as long as the distance between subject and background is the same). But the character of the lens will remain the same

Jul 09, 2009 at 05:54 PM


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