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Feb 14, 2015 20:11:29   #
CharleneT Loc: South Carolina
 
I have a Nikon d70 and an 18-55mm lens. I have set my camera on macro. The first picture is with auto focus. I tried manual focus on the second picture, but still have some blurriness. Is there something else I can do? Thank you.
Picture 1 auto focus
Picture 1 auto focus...
(Download)
Picture 2 manual focus
Picture 2 manual focus...
(Download)

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Feb 14, 2015 20:20:26   #
TucsonCoyote Loc: Tucson AZ
 
Your problem is not a lack of focus, it's a DOF condition .....from what I can see!
I've seen some very good results in macro from stacking .....just wait for the experts to file in and in the meantime do a search and a lot of reading ! :)

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Feb 14, 2015 20:27:37   #
Nikonian72 Loc: Chico CA
 
TucsonCoyote wrote:
Your problem is not a lack of focus, it's a DOF condition.
Absolutely correct. The shorter the Working Distance (lens front element to subject), the more narrow the Depth of Field, especially at medium (f/7.1) to large apertures.
Exif info:
Camera Model: NIKON D70
Image Date: 2015-02-14
Focal Length: 40mm
Aperture: ƒ/7.1
Exposure Time: 0.0080 s (1/125)
Exposure Bias: none
Metering Mode: Matrix
White Balance: Auto
Flash Fired: Yes

To increase your DoF, reduce your aperture to f/16 (but no smaller), and increase your speedlight output to compensate exposure.

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Feb 14, 2015 20:30:51   #
Nikonian72 Loc: Chico CA
 
This YouTube video mostly discusses diffraction, but also touches on DoF and focus. Worth a look:
http://www.youtube.com/watch?v=N0FXoWdHXTk&feature=em-subs_digest

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Feb 14, 2015 22:04:53   #
Apaflo Loc: Anchorage, Alaska
 
TucsonCoyote wrote:
Your problem is not a lack of focus, it's a DOF condition .

There is only a minor problem with DOF in the second image. The single object extending outwards down in the lower center is closer to the camera than DOF. It can be sharpened to help a little.

But the edges on the left side at the corners in particular though also along the top and the bottom, are blurred. The right side doesn't show that, primarily because this is a 5:4 crop from the original and almost certainly it was space on the right side that was trimmed. In the original that area would probably show, assuming there is something there to be compared with, the same blur.

That seems to be a lens with a sharp center and perhaps not exactly great sharpness at the edges. I'm not familiar with the "AF-S DX Zoom-Nikkor 18-55mm f/3.5-5.6G ED II" and can't speak to the general quality it may or may not have. It is obviously a consumer grade lens and perhaps a kits lens too? At 40mm stopping down to f/7.1 probably isn't quite enough to get the sharpest results, nor does it provide enough DOF to overcome field of focus curvature at the edges.

For many newly minted flower photographers those imperfections might not be noticed. But if the OP is critical enough to question why, maybe the real answer is "buy a better lens!"

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Feb 14, 2015 22:29:42   #
CharleneT Loc: South Carolina
 
I appreciate your helpful insights. If I was to get a better lens, any suggestions? I' don't have a lot of extra cash so expensive lenses are out of the question.

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Feb 14, 2015 23:45:22   #
Apaflo Loc: Anchorage, Alaska
 
CharleneT wrote:
I appreciate your helpful insights. If I was to get a better lens, any suggestions? I' don't have a lot of extra cash so expensive lenses are out of the question.

We'd have to know a lot more detail about what direction you want your photography to go! Are flower pictures similar to these the primary target, and are there other secondary targets? Do you like bugs, or coins, etc etc. Also do you have prints made, or just view the images on the computer?

That 18-55mm lens costs all of $120 brand new, so it's hard to find an economically competitive replacement! If you need or specifically want Auto Focus the price probably starts at something called "expensive" regardless of the quality. If you can work with a manual focus lens it is possible to pick up a used lens that is as good as it gets for under $400 (and with patience for even half that).

Any 105mm f/2.8 macro lens made by Kino Precision Optical will, in good shape, be great. They come branded with several different names. Kino sold them as Kiron in the US, Panagor in Europe. Lester A Dine, Soligor and Avenon are other brands. One common version is the Vivitar Series 1 set of 100mm and 105mm macro lenses. They are sometimes labeled f/2.5 and sometimes f/2.8. The significant point is that the serial number for the Kino made Vivitar lenses will start with "22".

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Feb 15, 2015 17:40:33   #
SonyA580 Loc: FL in the winter & MN in the summer
 
CharleneT wrote:
I appreciate your helpful insights. If I was to get a better lens, any suggestions? I' don't have a lot of extra cash so expensive lenses are out of the question.


The flower petals are sharp enough - I doubt another lens could improve the clarity or color that much. Looks to me like you focused on the petals at a relatively large aperture leaving the objects in the center out of focus. If you are concerned about not being able to get all of the flower in focus, you could change to a higher f/stop so, as mentioned above, you would get more depth of field. If in fact you are focusing on the center stamens, you have a back focusing problem with either the lens or the camera body.

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Feb 15, 2015 18:04:51   #
TucsonCoyote Loc: Tucson AZ
 
Apaflo wrote:
There is only a minor problem with DOF in the second image.The single object extending outwards down in the lower center is closer to the camera than DOF.
.....

Allrighy then.....what the hell does that mean??? :roll:

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Feb 15, 2015 18:11:14   #
Apaflo Loc: Anchorage, Alaska
 
TucsonCoyote wrote:
Allrighy then.....what the hell does that mean??? :roll:

There is only one object in the photograph that extends outside the
DOF.

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Feb 15, 2015 18:12:35   #
CharleneT Loc: South Carolina
 
So if I increase the DOF, the whole flower should be more focused? Would it also help if I focus on the part closer to me? I would think a longer DOF would bring the rest into sharper focus. I'll try it and see what happens.

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Feb 15, 2015 18:17:12   #
Nikonian72 Loc: Chico CA
 
CharleneT wrote:
So if I increase the DOF, the whole flower should be more focused? Would it also help if I focus on the part closer to me? I would think a longer DOF would bring the rest into sharper focus. I'll try it and see what happens.
As i posted above: "To increase your DoF, reduce your aperture to f/16 (but no smaller), and increase your speedlight output to compensate exposure."

Also, focus about 1/3 into your subject, as DoF is NOT 50/50 from narrow point of focus, but weighted more behind actual focus point (really an arc, not a point).

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Feb 15, 2015 18:24:05   #
TucsonCoyote Loc: Tucson AZ
 
CharleneT wrote:
So if I increase the DOF, the whole flower should be more focused? Would it also help if I focus on the part closer to me? I would think a longer DOF would bring the rest into sharper focus. I'll try it and see what happens.

Right.....listen to Nikonian72.....he is the master of close-ups/macro......check out his postings and what he says .....welcome to UHH btw.

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Feb 15, 2015 18:38:13   #
Apaflo Loc: Anchorage, Alaska
 
Nikonian72 wrote:
As i posted above: "To increase your DoF, reduce your aperture to f/16 (but no smaller), and increase your speedlight output to compensate exposure."

That will also increase diffraction, and while the edges will be "in focus", the center will no longer be sharp.

We don't know how much more light the flash can provide, but this is a D70 and the ISO is already too high at 400. Plus the added DOF from a smaller aperture is probably not going to help the corners much.

Bracketing both aperture (at f/7, f/8, and f/11) would be interesting. So would using ISO 200. And so would focus bracketing with shots focused a little closer to the camera. Another option would be to move back just slightly and use a longer focal length (50mm and 55mm rather than 40mm). And then back up slightly more and crop it slightly closer in post processing.

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Feb 15, 2015 18:41:54   #
Nikonian72 Loc: Chico CA
 
Charlene, are you using the camera's pop-up flash, or a hotshoe speedlight?

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