[PALADIN85020]

I've been looking for a single "walk around" lens for my K-5 that will enable me to travel light, such as while on vacation, where I can't carry around my full kit of lenses and accessories. After some deliberation, I settled on the Pentax 18-135mm WR zoom. I figure it would cover me from moderate wide angle to moderate telephoto (27 - 207mm equivalent in 35 mm terms) without having to change lenses. I liked the weather resistant claim, as I anticipate I'll sometimes be shooting in rainy weather. Although it's not a particularly fast lens, if it's coupled with the K-5's awesome ISO capability, it should be quite versatile. I've seen most of the reviews on this lens, and some knock it for distortion and/or CA, but I figure that again, the K-5's compensation settings could address these issues. I was favorably impressed by reports of the autofocus being fast, accurate and silent. So I took the leap and ordered one from B&H, and it arrived yesterday.

This morning I decided to try the lens under the worst possible lighting conditions - ambient light in my house (which is fairly dim even in the daylight hours), no artificial light or flash. This would be a chance for the K-5 to show its stuff and for the lens to show its versatility. These are random shots of objects in the house just to see how they would turn out.

This first pic is of some artificial flowers in our living room.
K-5 ver. 1.03, f/f.6, 1/30 sec., 115mm, ISO 3200:



Here is a picture of the "family clock" - it has been more or less continuously running since my uncle gave it to my mother and father as a wedding present in 1936. The date function has worn out, but it still keeps perfect time. I guess they don't make them like they used to!
K-5, ver. 1.03, 1/40 sec, f/5.6, ISO 3200, 88mm:



And finally, this is a pic of a bust for which my late father-in-law modeled, it's called "The Judge," crafted by artist James Muir, a member of our extended family.
K-5, ver. 1.03, 1/13 sec., f/5.6, ISO 3200, 88mm:



All shots were hand held. I think the combination of the K-5's great ISO capability, its shake compensation feature, and this lens with its fast, accurate and silent autofocusing worked out great. The colors seem true and the images sharp. Other than downsizing, no post-processing was employed on these photos.

I show these as test shots under the worst possible lighting conditions. I have no doubt that the lens will perform admirably in daylight in an all-purpose role for light travel.

What do you think?

John

[NewportPreacher]

Well, at that size, they look great, even w/out considering the high ISO you had to use. You make me discontent with my K20D! Now I want a K-5! :-)

[PALADIN85020]

Next, I went outside, seeing if claims of CA and distortion proved true. Not if this shot (cropped to show relevant portions) is any indication. This was taken from my back porch; K-5, ver. 1.03, 1/320, F/20, 48mm, ISO 320. In my opinion, CA disappears when you stop way down, and any distortion is taken care of by the camera. This was shot in TAv mode.



I love the K-5, and I think the 18-135 WR is a perfect match for an almost do-all lens. I would not hesitate to take it as my only lens on hikes/vacations where minimal gear is a requirement.

John

[Ash]

Good account on this good lens - one that was needed for some time, with or without the DC motor.
The WR component of it makes it a versatile all-rounder contending with rival brands.

[stevelink]

Awesome shots, John!
Well, my big question is how to set my K-5 for maximum sharpness with a given lens??
I am a “sharpness nut”, which is why I got the K-5 over the Nikon D7000. However, I am having some issues with sharpness “out of the box” with certain lenses, like the DA 15mm Limited, and possibly the DA 16-45mm. I shot a “test shot” handheld with my Pentax K-5 and DA 16-45mm, with Custom AF Adjustment at +8, as well as USM. This was a trial and error setting, but I think this is sharp, but still not sure if I’m getting ALL the resolution and sharpness I can. I'm wondering if you know of a "best practice" for calibrating DA lenses on a K-5. Thank you!

[Dr_who]

Awesome shots, John!
Well, my big question is how to set my K-5 for maximum sharpness with a given lens??
I am a “sharpness nut”, which is why I got the K-5 over the Nikon D7000. However, I am having some issues with sharpness “out of the box” with certain lenses, like the DA 15mm Limited, and possibly the DA 16-45mm. I shot a “test shot” handheld with my Pentax K-5 and DA 16-45mm, with Custom AF Adjustment at +8, as well as USM. This was a trial and error setting, but I think this is sharp, but still not sure if I’m getting ALL the resolution and sharpness I can. I'm wondering if you know of a "best practice" for calibrating DA lenses on a K-5. Thank you!

Part of it may be the obvious front focus or back focus issues. But if you look up the lens your using often a particular lens has a sweet range of apertures that is its sharpest. Just cause the 50mm 1.4 can open to 1.4, doesn't mean its not a good idea to stop down to 1.8 or 2 just to get that sharpness in. Also for landscapes if you focus on the farthest thing, I find its not as good as focusing on the hyper focal point. Just my 2 cents anyways

[PALADIN85020]

Awesome shots, John!
Well, my big question is how to set my K-5 for maximum sharpness with a given lens??
I am a “sharpness nut”, which is why I got the K-5 over the Nikon D7000. However, I am having some issues with sharpness “out of the box” with certain lenses, like the DA 15mm Limited, and possibly the DA 16-45mm. I shot a “test shot” handheld with my Pentax K-5 and DA 16-45mm, with Custom AF Adjustment at +8, as well as USM. This was a trial and error setting, but I think this is sharp, but still not sure if I’m getting ALL the resolution and sharpness I can. I'm wondering if you know of a "best practice" for calibrating DA lenses on a K-5. Thank you!

Most lenses do have a "sweet spot" for sharpness. My rule of thumb is to move up a stop or a two from wide open. If a lens has a max aperture of say, f/5.6, move it up to f/8. It's maybe counterintuitive, but stopping way down to like f/16 or f/22, for example, may not give you maximum sharpness. It simply increases your depth of field, and may help to prevent chromatic aberration.

If you really want max sharp from your camera and lens, then use a tripod and go full manual to control both aperture and exposure. When doing this, use the 2-second delay to let the mirror slap vibrations subside, or use the mirror-up setting. Also dispense with any filters and use a lens shade. Then you will have as good as it gets.

Most zooms will also have a sweet spot for minimum distortion. On this 18-135mm, I've found that the least distortion, either barrel or pincushion, is found in the range of 24-30mm. To me, that's important only when doing architectural shots where I want to be sure that I have straight lines rather than curved. At other settings and other subjects, distortion is minimal and can be corrected within the camera with compensatory settings.

If I'm going to print or publish an image, I almost always will apply some sharpening in post-processing. I use Photoshop Elements 7, and it does a good job. I think most of the commercial shots you see published are also post-processed for sharpening; you cannot expect razor sharpness direct from most cameras.

I photograph firearms as part of my job - here's an example using all of the above techniques. It was shot with the Pentax 18-55mm kit lens - nothing special.

Hope this helps.

John

[Skog]

This was my first snapshot with the k-5 and da 18-135. It's shot wide open at 135mm, and I put exactly 0 effort into taking it. Seems sharp to me, and looks promising when I learn to use it.

[PALADIN85020]

Skog, sure looks sharp to me! Although not a macro lens, the 18-135 can get in pretty close, and with the large 16.2 mp photos the K-5 generates, cropping can bring up pretty small details. Nice shot.

John

[LaurenOE]

Nice Skog!

[Gimbal]

And finally, this is a pic of a bust for which my late father-in-law modeled, it's called "The Judge," crafted by artist James Muir, a member of our extended family.
K-5, ver. 1.03, 1/13 sec., f/5.6, ISO 3200, 88mm:

I held my hand in exactly the same position when I scrolled down and this picture came up. Kind of freaky.

[Skog]

Skog, sure looks sharp to me! Although not a macro lens, the 18-135 can get in pretty close, and with the large 16.2 mp photos the K-5 generates, cropping can bring up pretty small details. Nice shot.

John

Thanks. This is a full frame shot by the way, no cropping involved. I'm not sure how far away from the minimum distance though. Not as close as possible I think. Cropping would be easy yes, it's sharp at pixel peep level. Not like my da 35 limited, but impressive for a zoom lens! A super zoom at the extreme focal length shot wide open, is hardly what you would consider to be optimal hehe, but it delivers.

[asdf]

If a lens has a max aperture of say, f/5.6, move it up to f/8.

A quality f/4 lens and a quality f/1.4 lens intended for a 135 or APS-C camera will both be sharpest at around f/5.6 in the center. Regardless of the max aperture, the image will be evenly sharp at around f/8. The max aperture does not necessarily affect the aperture at which sharpness peaks.