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Old Apr 12, 2014, 12:27 PM   #11
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The FZ150 has a small image sensor, so it has a pretty deep DoF anyway, and while stopping down usually will make the DoF deeper, the FZ150 doesn't actually have a diaphragm, so changing the f-stop won't change the DoF.
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Old Apr 12, 2014, 9:25 PM   #12
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But I thought that smaller aperture implies greater DOF???
...... john
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Old Apr 13, 2014, 1:41 AM   #13
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Quote:
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But I thought that smaller aperture implies greater DOF???
...... john
I see a very noticeable increase in depth of field when I stop down the FZ28 from f/2.8 to f/8. Not a huge change from f/5.6 to f/8 that you should be at, but you should be able to see it after a test shot.
 
I'm more concerned if it's the depth of field or the distortion in the lenses that you have that is confusing you. If those lenses have distortion, they'll look like they have no depth of field.
 
If you focus on a flat surface like a box with a label, everything from corner to corner should be sharp, regardless of the aperture. If it's blurry outside the center, that's distortion.
 
Focusing on the text on the computer screen should work for a test.
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Old Apr 13, 2014, 3:15 AM   #14
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The FZ150 has a 1/2.3" size image sensor, which is the smallest size commonly used in P&S cameras, and only larger than the sensors used in smartphones.

DOFMaster.com's on-line DoF calculator for the Panasonic Lumix FZ150 at full telephoto (108mm) wide open (f/5.2) and a subject distance of 12 inches has a total DoF of 0.01 inches. That will be true whether you use a set of cheap close-up lenses or a $75 Raynox DCR-250. The DoF gets much deeper as the focal length gets shorter, but for the same magnification, the subject distance must get a lot shorter. At full wide (4.5mm) wide open (f/2.8) and a subject distance of 1 inch, the total DoF is 0.03 inches.
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Old Apr 13, 2014, 9:46 AM   #15
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Hi BB/TCav,
I tried what you suggested, and I could not see any distortion in the (+3) lens. I also tried changing the aperture, at the shortest focal length, and noticed a significant difference in DoF between 2.8 and 8.0. (My way of measuring the DoF is to sight the camera along a ruler. It's crude, but seems to work.)
Just as an aside ....... I also noticed that there is one spot in the field where f2.8 produces a slightly sharper image than f8.0. This is true both with and without the +diopter.
...... john
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Old Apr 13, 2014, 10:59 AM   #16
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Give it a shot. Buy a Raynox. See how it works for you. There's no reason to believe that the result will be significantly different from what you're getting now.
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Old Apr 13, 2014, 4:28 PM   #17
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G'day John

May I add my 2-bob's worth as well...
I use the Canon 250D on my Panny FZ & G2 dSLR
The 250D has a focus of 250mm from lens to subject [ie: it is a +4 dioptre lens] - it is a 2-element lens and is "reasonably sharp" across the image plane. I say 'reasonably sharp' as we're comparing a $100 lens unit with an $800-1000 macro lens unit for a dSLR... well the expensive one does have a 'slight' advantage For me on a limited budget, I'll accept a 90% sharpness & 100% convenience for 10~20% of the price of the full macro lens for the occasional use during the year

Using the 250D and setting the camera on tripod with 250mm between the front lens & the subject, I can then use the whole zoom to alter the image size ~ ie: a great way to get in close to stuff

The "howevers" are ...
The FZ only stops down to f9 but the small sensor gives the impression of depth of field - so I can get some quite reasonable results. The G2 with its much larger 4/3rds sensor stops down to f22 and thus I get more depth of field this way ~ but exposure times increase and so does subject movement in the breeze etc

Reports I have read re- the Raynox show it to be very similar to the Panny or Canon equivalent lenses - each is 2-elements ... and I would avoid 'cheap & nasty' no-name copies from the internet

Hope this helps a bit
Phil
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Old Jun 4, 2014, 12:06 PM   #18
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Hi all,
Is it right to assume that DOF varies inversely with increasing diopter?
.... john
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Old Jun 4, 2014, 3:06 PM   #19
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Late to the party here...but...
TCav... are you sure the "150" doesn't have a diaphragm...?
See these 2 pics- one at f/3.4, the other at f/8....
Focus area fixed on badge on torch....
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Old Jun 4, 2014, 4:55 PM   #20
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Quote:
Originally Posted by TCav View Post
The FZ150 has a small image sensor, so it has a pretty deep DoF anyway, and while stopping down usually will make the DoF deeper, the FZ150 doesn't actually have a diaphragm, so changing the f-stop won't change the DoF.
Quote:
Originally Posted by SIMON40 View Post
Late to the party here...but...
TCav... are you sure the "150" doesn't have a diaphragm...?
See these 2 pics- one at f/3.4, the other at f/8....
Focus area fixed on badge on torch....
My mistake. Thanks for calling me on this.

While many P&S cameras use a simple neutral density filter to alter the exposure, the FZ150 has an actual diaphragm.
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