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01-10-2014, 05:49 AM   #46
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QuoteOriginally posted by MJSfoto1956 Quote
Here is a photo of the setup:
Holding the flower in a clamp is such a clever idea, I'm ashamed to have never thought about it! What tools are you using exactly?

QuoteOriginally posted by boriscleto Quote
1/40s @ 300mm handheld. (But at 12MP).
12 MP will not show the problems that Nikon shooters seem to deal with.

QuoteOriginally posted by saladin Quote
What's the D7100 like for shutter actuation? Nikonians might be suffering from mechanical issues in combo with the higher res sensor? I don't know if that's the case, Just idle thoughts on my behalf.
That's a pretty good secondary hypothesis. My colleague is supposed to go to a store and test the WR hypothesis, if it's not conclusive then this is a plausible cause.

01-10-2014, 06:26 AM   #47
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It's Gotta Be Rigged!

QuoteOriginally posted by fyby Quote
Thats interesting! Also interesting thing is when you go to dxomark and compare new sigma 35 1.4 sharpness chart for k3 and d7100 . When d7100 user see this, he must think if I have blurred images, k3 has to be total mess.
Wow! I can't believe there's such a variation in the results of the tests for the same lens on 24MP sensors. I'm sure these sites get paid by Nikon, how else can you explain the huge difference in sharpness tests for that lens? Even the CA is completely different.
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Last edited by bossa; 01-10-2014 at 06:39 AM.
01-10-2014, 06:43 AM - 1 Like   #48
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I've never shot *without* a tripod.
It's rare that I hand-hold anything.
(except someone's hand)
01-10-2014, 07:06 AM   #49
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QuoteOriginally posted by bossa Quote
Wow! I can't believe there's such a variation in the results of the tests for the same lens on 24MP sensors. I'm sure these sites get paid by Nikon, how else can you explain the huge difference in sharpness tests for that lens? Even the CA is completely different.
1) How do you get the page to show these charts?

2) They had tested the DA*300 and gave it really low resluts which does not correspont to what I see when shooting with it. Am I missing something?

01-10-2014, 07:37 AM   #50
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QuoteOriginally posted by bossa Quote
Wow! I can't believe there's such a variation in the results of the tests for the same lens on 24MP sensors. I'm sure these sites get paid by Nikon, how else can you explain the huge difference in sharpness tests for that lens? Even the CA is completely different.
Many people make a false assumption: that two sensors both manufactured by Sony and both delivering 24mp therefore *MUST* behave similarly with any given lens. Nothing could be further from the truth. There are many ways a sensor can be "tuned" to a manufacturer's lenses and vice versa: there are many ways a lens can be "tuned" to make the most of a given sensor. This is one of the disadvantages of a 3rd party manufacturer -- they must choose which sensors to "aim" for and which to not worry about. In this case, a better assumption would be that Sigma engineers likely exploited the characteristics of the popular Nikon sensor and didn't take into account the particular behaviors/engineering of the Pentax sensor. One will notice that in the same DxO test the Pentax version quickly "catches up" to the Nikon version as you stop down suggesting that the behavior of the outer sensor's "photon well" are different between the two.

J Michael
01-10-2014, 08:27 AM   #51
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QuoteOriginally posted by LaurenOE Quote
I've never shot *without* a tripod.
It's rare that I hand-hold anything.
(except someone's hand)
Fair enough, but for most people using a tripod is the exception, not the rule.
01-10-2014, 08:34 AM   #52
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QuoteOriginally posted by bdery Quote
Fair enough, but for most people using a tripod is the exception, not the rule.
I've never understood that.
With a tripod *you* are in creative control.
Shooting hand-held you are often at the whim of available parameters to get the shot.

Granted, *every* photograph is a compromise, but with a tripod you get to redo your shot and try different combinations.

Now what is *on* that tripod also makes a difference, and I put gimbals, ball heads, video heads, sliders, Jibs..etc.etc.etc.

Very few times I am just *holding* my camera.

01-10-2014, 08:46 AM   #53
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QuoteOriginally posted by LaurenOE Quote
I've never understood that.
With a tripod *you* are in creative control.
Shooting hand-held you are often at the whim of available parameters to get the shot.

Granted, *every* photograph is a compromise, but with a tripod you get to redo your shot and try different combinations.

Now what is *on* that tripod also makes a difference, and I put gimbals, ball heads, video heads, sliders, Jibs..etc.etc.etc.

Very few times I am just *holding* my camera.

Then you shoot different things. Granted, when I do interiors, I'll absolutely use a tripod. There's no way I could do panoramas with exposure rows and sensor shifting without a tripod. But say I'm walking around, taking photos of things and people, trying to capture interesting moments, there's no way I could use a tripod. Landscape would be like interiors, but I'm not sure I'm willing to carry my tripod if I'm not paid for it.

I did get quite a shock when I looked closely at my photos from the K-5... with my *istDS I had no problems shooting handheld, sometimes from the hip. And that was without the SR. But with the K-5... and the K-3 is even more extreme.

01-10-2014, 08:57 AM   #54
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QuoteOriginally posted by bdery Quote
Fair enough, but for most people using a tripod is the exception, not the rule.
I would have to say I use a tripod 65% of the time. Yes I shoot landscapes mainly, but I've also been known to lug my tripod around and use it as a pseudo-mono pod when taking images of birds and wildlife. Depends on the terrain and my energy level. If I'm just going out for an hour and a "see what there is to see critter wise" quickie, I'll leave the tripod at home. If it's a planned day trip, or I'm going after unique animals on a photo adventure, I'll take my tripod because that extra amount of stability can make a great deal of difference in capturing a sharp image.
01-10-2014, 10:20 AM   #55
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QuoteOriginally posted by kadajawi Quote
Then you shoot different things. Granted, when I do interiors, I'll absolutely use a tripod. There's no way I could do panoramas with exposure rows and sensor shifting without a tripod. But say I'm walking around, taking photos of things and people, trying to capture interesting moments, there's no way I could use a tripod. Landscape would be like interiors, but I'm not sure I'm willing to carry my tripod if I'm not paid for it.

I did get quite a shock when I looked closely at my photos from the K-5... with my *istDS I had no problems shooting handheld, sometimes from the hip. And that was without the SR. But with the K-5... and the K-3 is even more extreme.
True. When I can't take a tripod, then I take one of my monopods. When I can't take a monopod, I take a Gorilla pod. When I can't take a Gorilla pod, I take a clamp of sorts. When I can't take a clamp or some kind of stabilization, then I make sure I am using one of my sub f/2.0 lenses. When I can't do any of the above - then I'm probably not taking pictures or pictures are not appropriate.

QuoteOriginally posted by nomadkng Quote
I would have to say I use a tripod 65% of the time. Yes I shoot landscapes mainly, but I've also been known to lug my tripod around and use it as a pseudo-mono pod when taking images of birds and wildlife. Depends on the terrain and my energy level. If I'm just going out for an hour and a "see what there is to see critter wise" quickie, I'll leave the tripod at home. If it's a planned day trip, or I'm going after unique animals on a photo adventure, I'll take my tripod because that extra amount of stability can make a great deal of difference in capturing a sharp image.
Yep.
01-10-2014, 11:27 AM   #56
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QuoteOriginally posted by LaurenOE Quote
When I can't do any of the above - then ...probably (my) pictures are not appropriate.
another definition of wildlife photography?
01-10-2014, 02:18 PM   #57
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QuoteOriginally posted by Tjompen1968 Quote
1) How do you get the page to show these charts?

2) They had tested the DA*300 and gave it really low resluts which does not correspont to what I see when shooting with it. Am I missing something?
Sigma 35mm F1.4 DG HSM A Pentax on Pentax K-3 versus Sigma 35mm F1.4 DG HSM A Nikon on Nikon D7100 - Side by side lens comparison - DxOMark
01-10-2014, 02:26 PM   #58
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QuoteOriginally posted by MJSfoto1956 Quote
Many people make a false assumption: that two sensors both manufactured by Sony and both delivering 24mp therefore *MUST* behave similarly with any given lens. Nothing could be further from the truth. There are many ways a sensor can be "tuned" to a manufacturer's lenses and vice versa: there are many ways a lens can be "tuned" to make the most of a given sensor. This is one of the disadvantages of a 3rd party manufacturer -- they must choose which sensors to "aim" for and which to not worry about. In this case, a better assumption would be that Sigma engineers likely exploited the characteristics of the popular Nikon sensor and didn't take into account the particular behaviors/engineering of the Pentax sensor. One will notice that in the same DxO test the Pentax version quickly "catches up" to the Nikon version as you stop down suggesting that the behavior of the outer sensor's "photon well" are different between the two.

J Michael
Really? How different sensor can change plane of sharpness of lense? Easiest explanation is that there was need to microadjust af in case of K3.
01-10-2014, 02:52 PM   #59
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actually, it is rather well documented that sensors don't behave at all like film. The design of the sensor's "photon well" determines the ability of each individual sensor to capture photons at specific ANGLES. If the lens presents the photons at the wrong angle as expected by the sensor engineers it will not perform. The best example of this was poor old Leica -- its old classic film lenses were quite close to the film and as a result all of their wide angle lenses performed poorly on standard sensors. This is why their initial sensors were crop sensors -- they couldn't get it right until after many years work came up with a Leica-designed FX sensor (manufactured by one of the big sensor companies) that had the outer sensors essentially at a slight angle instead of looking straight-ahead.

Again, it is a fairly common mistake to assume that sensors behave like film and even that same sized sensors behave similarly. Nothing could be further from the truth. Near as I can tell DxO has a robust methodology when testing lenses -- after all, they sell their data back to the camera manufacturers for use as embedded systems. They can't afford to publish crap.

Michael

Last edited by MJSfoto1956; 01-10-2014 at 03:15 PM.
01-10-2014, 02:58 PM   #60
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Is the difference due to the sensor or due to difference in the both lenses on tolerance from the manufactoror?
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