[heliphoto]

Just a teaser really... I wrote up a description here, but I started thinkin' it would make a good blog post (well at least a blog post ), so now it is one and this here's a pointer to it.

The teaser pics...





If you missed the link above, the blog post is here...

[roentarre]

Thanks for such a great effort posting this comparison of images according to various apertures. Your writing on the blog is quite fun to read too.

For a lot of testers, it is often a common practice to shoot 10 frames for each aperture setting before going to the next aperture. Less errors.

[heliphoto]

Thanks for such a great effort posting this comparison of images according to various apertures. Your writing on the blog is quite fun to read too.

For a lot of testers, it is often a common practice to shoot 10 frames for each aperture setting before going to the next aperture. Less errors.

Thanks James. Ten frames?, but I don't shoot ten frames of a subject before I move on (ok, I suppose I do sometimes - perhaps I should more often). This was really just a quick an dirty test to satisfy my own curiosity, but I figured I might as well put the results out so others could benefit - it's such a rare lens.

I'm surprised you find my writing fun to read (I would think it's annoying that I use so many parentheses (but I can't seem to avoid 'em)). Maybe it's the challenge.

[Lowell Goudge]

one thing I noticed is that the tap on the wall is not at the center of the frame, where focus sensor would be expected to pick up focus confrimation with an AF sensor.

what did you focus on, and how did you focus because your assessment may be more related to focus error (by the operaotr) than the lens sharpness improving.

I do agree however withthe assessment of CA and this does improve as you stop down.

just as an aside, the K300 F4 has slightly shorter focusing (down to about 11 feet) and 270 degrees of focus collar rotation.

Additionally (just to keep peter Zack and others from pointing this out) You should put the technical aspects of your review in the database

[heliphoto]

one thing I noticed is that the tap on the wall is not at the center of the frame, where focus sensor would be expected to pick up focus confrimation with an AF sensor.

what did you focus on, and how did you focus because your assessment may be more related to focus error (by the operaotr) than the lens sharpness improving.

I do agree however withthe assessment of CA and this does improve as you stop down.

just as an aside, the K300 F4 has slightly shorter focusing (down to about 11 feet) and 270 degrees of focus collar rotation.

Additionally (just to keep peter Zack and others from pointing this out) You should put the technical aspects of your review in the database

Thanks Lowell for the feedback. I believe I focused on the tap, though as you say, If my focus is off a bit, it would show the sharpening from the increased DOF... I tend to just look for sharpest focus in the viewfinder, and not to use the focus confirmation when manually focusing, because I never got good results on my K200D that way, so I got out of the habit (never got into the habit). Now on my K20D, I notice that I get the green hexagon when I think I've nailed the focus, so it does work as confirmation, but I don't think I rely on it yet... If you're interested in pixel-peeping (the ivy shot for instance), the full sized images are available (link is in the blog post). I don't have a Katz-eye or similar split image screen, so it's possible I was a bit off on focus - I dunno. Based on the this DOF calculator, it looks like the DOF with this setup (estimating 30' to the tap) would be ± 6 in. so I was clearly trying to focus on the tap, whether I succeeded or not.

I do intend to put writeups in the database, after I've had these lenses a while longer in order to form opinions on 'em.

[heliphoto]

Well between Lowell's (justified) doubt, and James' admonition that I might think about shooting 10 frames of each subject, and the likelihood that I'm gonna put this lens up on the marketplace tonight, I thought I'd better retest it - so I did.

I still didn't shoot 10 frames of each subject - just one each at f/4, f/5.6, and f/8 but I covered enough different subjects that questions about focus points should be moot now... The results stand though perhaps the lens isn't quiet as soft wide open as I previously thought. I shot 10MP jpegs (mostly) this time which of course change the results, but don't invalidate them - you can still see sharpness increase as the lens is stopped down.

Full size downloads of these shots and many others are available on my site, and I'll be adding a new blog post soon. Some of the shots there are taken using an extension tube to obtain closer focus (focused to approx. 5 ft.), all shots were taken with the lens mounted on a tripod with the two second timer used.

Here's a couple 100% crop samples below the full size f/8 photo...