[Adam]

The last two 100% crops for today. Also attached is a photo of the stop sign itself, about 15 meters away.

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Adam
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[VisualDarkness]

Why is the K-5 one so stripy?

[TenZ.NL]

Couldn`t that be the reflective paint of the sign? The stripes are present in all pictures but are more pronounced in the K5 shots. The K5IIs shot looks a little underexposed too.

I`m not sure but it seems that the focus of the K5 shot is slightly off. This doesn`t look like a good comparison?

[kiwi_jono]

Yeah it appears that the sign does have the stripes - see full image.

If the k-5 shot is in focus (and I imagine Adam has already checked that?) then the IIs is a big improvement in sharpness - just look at the fly.

[snostorm]

Actually, it would probably help if we could see the whole frame shot from each. This way it would be easier to determine where exactly the focus plane intersected the sign since the sign is angled in relation to the sensor plane and there are numerous contrast borders inside the focus sensor area that could have been chosen if AF or focus confirmation was used. If not, it would be helpful if the exact focus point in relation to the sigh was stated.

In the K-5 whole frame shot, for example, it appears that the focus was biased toward the "S" side of the sign which could make a difference in sharpness at the "O".

Comparisons of straight on shots of the sign with carefully micro focus calibrated cameras would possibly be more conclusive.

BTW, I don't doubt that the K-5IIs captures sharper, higher resolution images, I just don't think this demonstration proves anything.

Scott

[skyoftexas]

Notice the sensor stain in the left hand corner of the big photo?

[DeadJohn]

^ One man's sensor stain is another man's trees, birds, and utility poles.

[JinDesu]

^ One man's sensor stain is another man's trees, birds, and utility poles.

Those damn out of focus birds.

[RonHendriks1966]

Well one problem with this striping is that if the angle from the camera to the sign is just a little different then the whole scene does behave different and that could also make the difference.

[JinDesu]

I propose Adam hire me to go over and do it. I'm very good at these sort of things. Very good.

Or just send me the k-5IIs and the k-5~

I assume he did it with manual focus, so we can ignore AF issues.

[Adam]

For some reason, the stripes are much more pronounced in the K-5 shots than the K-5 IIs shots. I took four with each. To make comparisons such as this one valid, you've got to be able to re-create the results

[patrick9]

I am just amazed that Adam got the fly to stay there for 3 hours.
I do like the sharpness and shade of red of the IIs

[Class A]

BTW, I don't doubt that the K-5IIs captures sharper, higher resolution images, I just don't think this demonstration proves anything.

I fully agree.

Open questions:

1. Has the same lens copy been used on both cameras?
2. Why use different exposure times?
3. Why does the focus point seem to be on the "S" rather than on the "O" in the K-5 shot?
4. Has a tripod been used and were both cameras fired the same way (e.g., using a remote and mirror lock-up)?
5. Are you comparing JPG engines or did you convert RAW files with the same converter using the same settings?
6. Has the lens received AF micro-adjustment on both cameras?
7. Under which (identical?) conditions was the micro-adjustment performed?
8. What method was used to ensure that each camera obtained optimal focus?
9. Why do you not apply the necessary capture-sharpening to shots from the K-5? The Bayer AA-filter is designed to create (necessary) blur and this blur must be undone (ideally with deconvolution, but unsharp mask type sharpening is OK).

I'd say test conditions that lead to dramatic differences like shown here, but also to very subtle differences in other situations, aren't entirely reliable (yet).

Adam, could you please make both full images available so that we can compare where the centre of best focus is in both respectively?

[westmill]

You were there in life Adam ! which do you think is the most accurate rendition of how it was in reality. Ive noticed the K5 2s has a rather distinctive line around the 0 while with AA it does not.

[Class A]

Meanwhile, beholder3 has posted a link to another comparison:

Tiny, tiny differences, but they are there.

This (and other comparisons (e.g., this one, which also makes the error of not capture sharpening the K-5 shot) which show differences but nowhere near as dramatic as here) suggests that there might be a focusing issue with the K-5 and/or its lens used in the Pentaxforums comparisons.

Thinking about it, an FA* 85/1.4 at f/5.6 should not be as soft as the K-5 comparison shot seems to suggest it is. Admittedly, I'm not used to K-5 100% shots but it doesn't look right to me.

EDIT: Here's a comparison between K-5, K-5 II, and K-5 IIs. The K-5 shot doesn't look nearly as hopelessly soft as many of the images posted by Adam.