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11-25-2011, 12:19 AM   #1
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DFA100 Macro WR + AFA1.7x Converter usage report

Over at DPR. A poster started a thread a thread asking about using the 100WR with the AFA1.7

I happen to have this combo and didn't thought of using it this way until the suggestion.

I had the chance to do some quick tests the other day and here are my usage experience. Please do bear in mind I don't usually do any sort of lens test at all, I just use them in the field. So my test method or methodology may not be very strict (that's why I named it a usage report rather than testing).

1. The appearance: The AFA1.7 seem to be almost MADE for the FA100WR, or is it the other way round? They have roughly the same barrel diameter, and when fitted together, seem almost designed to be a pair despite the mismatched color. See the myriad of photos I took of the combo, fitted to the K-5, below.






















11-25-2011, 12:22 AM   #2
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2. Handling: When fitted to the K-5 the combo feels well balanced - it becomes a fairly long lens but the extra barrel length is great for grab hold onto using your hand. Although I would probably still use a tripod.

The AFA1.7 was designed for manual lens and adds limited AF capability to them. If you use any AF lens, such as the 100WR with it, you loose majority of the Auto Focus capability. By that it means you have to Manual focus the adapted lens to 'roughly' the correct focus point, then, when hald pressing the shutter or AF button, the AFA1.7 will attempt to 'snap' to the actual AF point for you.

All macro focus lens have a long focus throw, and a probably better operated as manual anyway (I haven't used macro lens from Canon/ Nikon with USM so can't make comment on if they are better @ AF). Using the 100WR with AFA1.7 's AF assist feels quite awkward - you gotta manually throw the lens to roughly the right focus distance anyway. The AFA1.7 has a very limited AF distance window, and more than likely not it has some difficulty to lock on in such close focal distance as the operating range of a Macro.

I would suggest using this pair as a purely manual combo - leave the camera in MF mode and just manual focus using the macro lens. However, this does cause some confusion about the exact zoom ratio you will achieve with the 100WR in the end result.

An alternative is to leave the AF on, using the method described above to achieve rough focus lock, then manually adjust the lens for fine tuning. Almost like a primitive version of "QuickShift"





11-25-2011, 12:24 AM   #3
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3. Reproduction ratio: The final Reproduction ratio of 100WR + AFA1.7 will be native Reproduction ratio of 100WR x 1.7. So let's say if you achieved a 1:1 rep ratio by being very close to your subject. The actual rep ratio is actually 1:1.7, ie, 1.7 times life size.

Another example, if you achieved a rep ratio of 0.4, then the final rep ratio of the combo is 0.68x life size.

I mentioned before there is a certain amount of confusion about the very exact, actual rep ratio of the final result. This is due to the AF mechanism of the AFA 1.7 - the adaptor has a set of short throw AF elements, and there is no focus distance indicator. So users do not the know the exact focus distance as seen by the adaptor. This small amount of difference in theory, affects the final rep ratio but in real life usage it's probably not that significant to be a bother.
11-25-2011, 12:26 AM   #4
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4. Macro image quality: The test subject is a 1 dollar Australian coin, the focus point is the 'D' of 'Dollar. At the point where the vertical '|' meets the ')'. I wish I had a better test subject, such as a paper 10 dollar bill, but being poor (no money after the LBA), the coin will have to do

The set is taken under natural light.

The first set is 1:1 rep ratio on the lens (so, somewhere around 1:1.7 final rep ratio):
1:1 crop from converted RAW, no additional sharpening applied.



















11-25-2011, 12:29 AM   #5
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The second set is 1:0.5 rep ratio (final ratio 1:0.85) 25% crop

















11-25-2011, 12:30 AM   #6
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A few extra photos taken with Flash (WB corrected in RAW conversion)










Bear in mind, none of these are sharpened, I tried sharpening a few in photoshop and result is great.

Also these are not taken under ideal conditions: camera is rested on a table, not a tripod, I have no ring flash etc. Notice that with flash the result seem to be a little shaper, either the light bouncing off the tiny scratches on the metal coin created an illusion of contract, and thus, sharpness, or the natural light pictures are a little affected by the relatively slow shutter speed.

I will not draw conclusions here, everyone is welcome to deduct their own impression from these.

Cheers
11-26-2011, 07:25 PM   #7
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Nice test. I also have that same combo and will have to try it out. Looks like it works well.
11-27-2011, 07:55 PM   #8
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the lens + adapter combo looks boss on the K5 =D

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