As others mentioned, 0.03 is not small enough for a 100% crop of the 5D2 (which is like looking at a 6 foot wide print up close).
But more importantly, why are you bothering with a tape measure and charts? At their very best they will still be less precise than 10X liveview, and are much slower besides.
Daniel, I'll switch to that for the Mk 2, but I also still have my original 5D and the 40D, so I'd still need a tape measure for those if I'm out in the field.
The experiment was to see how well the HFD thing worked.
Originally Posted by Alan
Of course; that makes perfect sense.
Try manual focusing on the hyperfocal distance using your distance scale. AF doesn't always hit the right spot.
when you are hyperfocal distance focusing you are placing the focal point on a subject matter. What this means is that obviously there is DOF in front and behind your focal plane. However, the calculation alone will not gurantee perfections in the lens opticals and what you are doing is placing too much demand on the lens at that aperture.
I would have used live view if i were you, and then focused on the tree, this would help with focus to begin with.
I woul also stop down the lens to F/8 or F/11.
What you also need to realize is that, at the far ends of the DOF buffer, that resolution is lost you aren't resolving as much. However, when viewing the print "normally" the background trees appear as sharp and within the DOF.
I believe if you stopped down to F/8 or F/11 you would see a noticable increase in the resolved trees.
FOcus on car @ F/2.8
aperture down to 4.0
Aperture to 5.6
Aperture to 8
While my focus did not change at all, I left all of that stationary, I did stop down my apertures and you will see how the items in the rear are better resolved. However, you just can't expect that great of a performance at F/4.
Also the following scenes are with the 17-40 L on an XSi
THe slices are full size and taken from images that look like this:
F/8
F/11
F/16
I believe this shows the other side of the Hyperfocal problem, where you resolve better at F/8 and the narrower you go, the more your image suffers from diffraction at 100% views.
The impression I got from Alan's post was not how to maximize DOF through hyperfocal technique, but rather, how to determine the hyperfocal distance for a given f-number and focal length. Therefore, the calculation demonstrates three principles: first, that the determination of the hyperfocal distance is sensitive to the CoC which in turn is dependent on the viewing conditions of the image; second, that the commonly stated CoC of 0.03mm for 35mm format is not suitable for 100% crop on a 5DmkII, as this corresponds to a particularly high enlargement ratio due to high pixel density; and third, that it is ideal to not have to determine these things empirically at the time of capture, and that simply stopping down is not the relevant approach for understanding this subject.
Thats fine.
If he used a relevant COC such as .019 he would have found:
<span style="word-spacing: 0px; font: 16px 'times new roman'; text-transform: none; color: #000000; text-indent: 0px; white-space: normal; letter-spacing: normal; border-collapse: separate; orphans: 2; widows: 2; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px;" class="Apple-style-span"]<span style="font-size: 11px; font-family: Arial;" class="Apple-style-span"]
<table summary="results of depth of field calculation" width="100%" style="padding: 4px;" class="resultsTable"]
<tbody>
<tr>
<td width="55%" align="left" valign="top" style="font-weight: bold; font-size: 12px; margin: 0px 5px 5px; color: black; font-family: Verdana, Arial, sans-serif; padding: 1px;" class="textClassResults"]Subjectdistance</td>
<td name="resultsDistance" align="left" valign="top" style="font-weight: bold; font-size: 12px; margin: 0px 5px 5px; color: black; font-family: Verdana, Arial, sans-serif; padding: 1px;" id="resultsDistance" class="textClassResults"]16ft</td>
</tr>
<tr>
<td colspan="2" align="top" style="padding: 1px;"]
</td>
</tr>
<tr>
<td colspan="2" align="left" style="font-weight: bold; font-size: 12px; margin: 0px 5px 5px; color: black; font-family: Verdana, Arial, sans-serif; padding: 1px;" class="textClassResults"]Depthoffield</td>
</tr>
<tr>
<td style="font-weight: bold; font-size: 12px; margin: 0px 5px 5px; color: black; text-indent: 20px; font-family: Verdana, Arial, sans-serif; padding: 1px;" class="textClassResults"]Nearlimit</td>
<td name="dofNear" align="left" style="font-weight: bold; font-size: 12px; margin: 0px 5px 5px; color: black; font-family: Verdana, Arial, sans-serif; padding: 1px;" id="dofNear" class="textClassResults"]9.75ft</td>
</tr>
<tr>
<td style="font-weight: bold; font-size: 12px; margin: 0px 5px 5px; color: black; text-indent: 20px; font-family: Verdana, Arial, sans-serif; padding: 1px;" class="textClassResults"]Farlimit</td>
<td name="dofFar" align="left" style="font-weight: bold; font-size: 12px; margin: 0px 5px 5px; color: black; font-family: Verdana, Arial, sans-serif; padding: 1px;" id="dofFar" class="textClassResults"]44.5ft</td>
</tr>
<tr>
<td style="font-weight: bold; font-size: 12px; margin: 0px 5px 5px; color: black; text-indent: 20px; font-family: Verdana, Arial, sans-serif; padding: 1px;" class="textClassResults"]Total</td>
<td name="dofTotal" align="left" style="font-weight: bold; font-size: 12px; margin: 0px 5px 5px; color: black; font-family: Verdana, Arial, sans-serif; padding: 1px;" id="dofTotal" class="textClassResults"]34.7ft</td>
</tr>
<tr>
<td colspan="2" style="padding: 1px;"]</td>
</tr>
<tr>
<td style="font-weight: bold; font-size: 12px; margin: 0px 5px 5px; color: black; text-indent: 20px; font-family: Verdana, Arial, sans-serif; padding: 1px;" class="textClassResults"]Infrontofsubject</td>
<td name="dofFront" align="left" style="font-weight: bold; font-size: 12px; margin: 0px 5px 5px; color: black; font-family: Verdana, Arial, sans-serif; padding: 1px;" id="dofFront" class="textClassResults"]6.2ft (18%)</td>
</tr>
<tr>
<td style="font-weight: bold; font-size: 12px; margin: 0px 5px 5px; color: black; text-indent: 20px; font-family: Verdana, Arial, sans-serif; padding: 1px;" class="textClassResults"]Behindsubject</td>
<td name="dofRear" align="left" style="font-weight: bold; font-size: 12px; margin: 0px 5px 5px; color: black; font-family: Verdana, Arial, sans-serif; padding: 1px;" id="dofRear" class="textClassResults"]28.5ft (82%)</td>
</tr>
<tr>
<td colspan="2" style="padding: 1px;"]</td>
</tr>
<tr>
<td style="font-weight: bold; font-size: 12px; margin: 0px 5px 5px; color: black; font-family: Verdana, Arial, sans-serif; padding: 1px;" class="textClassResults"]Hyperfocaldistance</td>
<td name="hyperFocal" align="left" style="font-weight: bold; font-size: 12px; margin: 0px 5px 5px; color: black; font-family: Verdana, Arial, sans-serif; padding: 1px;" id="hyperFocal" class="textClassResults"]24.9ft</td>
</tr>
<tr>
<td style="font-weight: bold; font-size: 12px; margin: 0px 5px 5px; color: black; font-family: Verdana, Arial, sans-serif; padding: 1px;" class="textClassResults"]Circleofconfusion</td>
<td name="cocused" align="left" style="font-weight: bold; font-size: 12px; margin: 0px 5px 5px; color: black; font-family: Verdana, Arial, sans-serif; padding: 1px;" id="cocused" class="textClassResults"]0.019 mm</td>
</tr>
</tbody>
</table>
Therefore, I advise consider stopping down to be with in the performance specifications he desired for his IQ.
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