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09-24-2013, 06:41 PM   #1
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Optimal aperture settings for DA*300 with Q7

Through trial and error we had determined that the DA*300 would work best on the Q when set to 5.6 or setting 1 on the K-Q adapter.

This test was done to determine if the Q7 has a different optimal setting for the DA*300.

The test was done at base ISO with the lens focused using a loupe for best accuracy.
The only variables were the change in the aperture setting via the K-Q adapter for each shot and a corresponding change in shutter speed to give correct exposure.

I used the adapter scale to determine the setting, with shots at 0 (open), .5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, 5, 5.5 and 6 on the dial.
The attached scale from the adapter manual determines the aperture.

Some users have indicated the resulting aperture was incorrectly calculated, my only concern was that the optimal setting could be repeated.














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09-25-2013, 01:36 PM   #2

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Hi Larry,

To my eye, it looks like optimal sharpness is still around aperture setting 1 -- maybe up to 1.5 -- or somewhere in between. There definitely seems to be a drop off by 2.

IMO, this is a relatively difficult test subject to judge from. Might I suggest that you try a feather to get consistent ultra fine detail in the subject. I bought a variety of feathers from a craft shop (Frank's, Hobby Lobby, etc) and use them to do tests. I angle the feather so I can pick a particular area to focus on, and I can check the actual DOF at the same time. To get this focus point, I smooth the feather so the barbles lock, then add a break by pulling them apart at one point. I also use the pop up flash to help eliminate any camera shake effect, even though I do the tests from a tripod. I use a reasonably bright artificial light source for focusing, then turn it off and allow the flash to supply the light for the test shots.

IMO, you're supplying some very good information in regards to the Q vs Q7. For my purposes, there doesn't seem to be much of an IQ reason to upgrade, but I am tempted by some of the features -- the ability to choose between the leaf shutter and electronic shutter for slower shutter speeds, the additional functionality of the front dial, AF during video mode are three changes that intrigue me, and the slightly wider perspective with the lower crop factor are all intriguing.


Last edited by snostorm; 09-25-2013 at 06:17 PM.
09-25-2013, 02:22 PM   #3
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Original Poster
Thanks Scott.

I was trying to figure out a better subject than the angel statue from the last and though this panda eye and ridges might work better but I had not thought about a feather.

The flash idea is good one. This is the first time I have really done any serious testing of a camera, up to now I just hoped for the best and would learn the best settings through trial and error.

I'm getting usable data for my purposes and figured I would share, but I also am finding that the IQ improvement is slight.

I'm hoping to be able to get out for some real world testing soon with both native and adapted lenses.
09-25-2013, 02:37 PM   #4

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Very little difference between 1 & 1.5, but 1.5 may be best (or I'm fooled by slightly greater DOF)...

09-26-2013, 05:54 AM   #5
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Thanks Larry you are keeping me on the fence here, I like the crop factor of the original Q for adapted lenses and the 06, but I can see the IQ improvement between my Q's and a 1/1.7 sensor compact I have that makes me want to upgrade. Now I am carrying both a Q with the 06 and the compact with a 24-120mm equiv. zoom. I am thinking if I upgrade I will still carry 2 cameras, Q W/ 06 and Q7 W/ 02 so I am still on hold.


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