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Old May 19, 2008, 3:34 PM   #1
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Just did that Monday May 19. DA*200mm plus Kenko 1.5TC vs A300mmF4. All images were taken with support and 2 s delay to minimise camera shake.
All were set at F4.5. I may be wrong as it seems to favor the DA*200mm as its F4.5 (from wide open at F2.8 ) may have an advantage over the A300mm at F4.5 (almost wide open)
Did I do it wrong by setting both at F4.5 ? I get pretty confused with the setting. The result seems to be so one-sided. May somebody suggest the right aperture for this subjective test?



DA*200mm plus Kenko 1.5 TC




A300mm










DA*200mm plus Kenko 1.5 TC centre





A300mm centre









DA*200mm plus Kenko 1.5 TC side





A300mm side




Daniel, Toronto
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Old May 19, 2008, 6:04 PM   #2
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daniel,
this a heart breaker...... the 200+1.5
clearly is the 200&1,5 is better.. i looked at the first shots before scrolling down and the rest of shots 2nd. you picked out exacting the areas i'd be asking for.. how about adding a 1.4or 2x to this setup?? i'm curious..

roy
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Old May 19, 2008, 6:31 PM   #3
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robar wrote:
Quote:
daniel,
this a heart breaker...... the 200+1.5*
clearly is the 200&1,5 is better.. i looked at the first shots before scrolling down and the rest of shots 2nd. you picked out exacting the areas i'd be asking for..
roy
Roy,

Why heartbreaker?
Did I do it wrong by setting both at F4.5 ? I get pretty confused with the setting. My only issue is that it is so one-sided. I will do another one at F5.6 for both set up and I would expect the sharpness of A300mm should improve a lot from F4.5 to F5.6 or 7.1
Quote:
how about adding a 1.4or 2x to this setup?? i'm curious..
I would not mind if you can loan me a 1.4x TC . Or better still 1.7x. 2x is likely not worth the trouble.

Daniel
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Old May 19, 2008, 9:39 PM   #4
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The 200mm is the better by far.

Would there be a big difference in the 1.5 to a 1.4 or 1.7. ? Seems such a minimal amount to make any difference. I would go to f5.6 or closemore with the 300mm, given the car is on the bright side, holds the light well, closing down should sharpen it up.
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Old May 19, 2008, 10:36 PM   #5
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It's a heartbreaker because I love my A300, had pretty much decided to get my 50-200 fixed rather than investing in a 200mm that's comparitively large and heavy, considering I really don't need 2.8 at that focal length. Then yougo posting pictures like this and get me second-guessing all this. And I really don't have any available extrabucks to spend on anything photographic at the moment.
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Old May 20, 2008, 5:22 AM   #6
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Hi Daniel,

thanks for the comparo, very interesting.

Simon
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Old May 20, 2008, 6:50 PM   #7
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My apology to all forum members re the mix up of aperture that I should be using for the comparison. It has been confirmed that I need to balance the F stop of the two setup.

I should have chosen the DA*200mm at F4 plus the 1.5Kenko TC compared with A*300mm at F6.5. I believe they are on level field now at least in terms of F stop. Here is the close up which is self-explanatory. All were taken with support and 2 s delay shutter to reduce camera shake to the minimum







200mm plus Kenko 1.5x












200mm plus Kenko 1.5x









Accordingly I have erased all the earlier images just in case people have drawn the wrong conclusion therefrom.



Daniel, Toronto
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Old May 20, 2008, 11:40 PM   #8
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Interesting thoughts about the TC and comparing it to a longer lens without a TC. Since adding the TC causes the lens to lose light, which makes the lens "slower" than it would normally be,and it's optical sharpness doesn't change since you haven't stopped the lens down any, just taken away the light. So while you are now comparing apples to apples (f4 200mm+TC to the f6.5 A300), I still think that your original series was very interesting. It might not be apples to apples, but it sure shows how nice the 200 really is. In fact, there isn't all that much difference in the current comparison, either. That's one really nice lens.
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Old May 24, 2008, 6:22 AM   #9
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One issue about the Kenko TC 1.4 & 1.5 and 2x. Because it does not reflect its presence, the SR will only work partially.
It is a AF combo and the SR is auto set to 200mm . But in fact it should have SR catered for 300mm.
Pentax 1.7x does reflect the true FL for the SR to work though.
Roy /Dawg /Scott with their lens chop shop would be able to tape and fool the camera about SR setting. But if you do tape it out, AF will not work.


Daniel

edited in later.
Just did a couple of shots a few hours ago (May 24 Sat) with DA200mm only without the TC






















The DoF at F3.5 was punishingly little



Daniel
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Old May 25, 2008, 12:14 PM   #10
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It sure has lovely color. Very nicely done - I'm going to keep this lens on my wish list.
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