[DW58]

New lens, DA* 300mm f/4. New camera, K-3. Other lenses AF just fine on the new K-3. With the 300mm on a tripod using 12 delay, spot focus on my license plate about forty feet away. f/4, 1/160, 200 iso plate is sharp. At f/5.6 less sharp. At f/8 still soft. As I stopped down never got better. Only apertures that seem sharp are f/4 and f/4.5.
This is my first lens this long and am wondering if I'm missing something or if it's simply a bad copy. My 30 day return to B & H is running out. Been raining a lot here so have only had it out three times. Any thoughts?

[Adam]

Do you get the same results off tripod or with a higher ISO? I'd crank it up to 3200 just to eliminate the possibility of blur.

If camera shake/mirror slap isn't to blame, then it sounds like the lens may be defective since stopping down should yield a better image. You should also be able to test this in live view with DoF preview activated.

[DW58]

Thanks Adam. First time out in the yard was hand held. Couldn't get a sharp image with iso up to 1600. That's the highest I went. Just thought my hand held technique with a lens this size was not good enough. Next time out tried to shoot lichen on a branch with the tripod. Images were soft. Branch was about a 45 degree angle so opened up to f/4 and fine tuned AF + and - to 5 each way. Original setting was best but did not change aperture at that time. So today I shot the license plate at all apertures and iso from 200-800. Raining again now but when it stops I'll try 3200 and run through the apertures again. I tried live view a couple of times with my K-50 but never had any luck. When I thought the white outline was sharp the camera obviously disagreed and I quickly gave up trying to figure it out but willing to try again.

[Adam]

When I thought the white outline was sharp the camera obviously disagreed and I quickly gave up trying to figure it out but willing to try again.

It's best to magnify (press OK) and then look at the sharpness. I've found it's actually easier to do it without focus peaking.

Adam
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[DW58]

I'm such a newbie. Didn't catch what you were saying the first time I read it through. I read live view and focus peaking just popped into my brain. Thanks for your help.

[Alex645]

Is SR turned off? Although it could be a rare diffraction problem with the lens, it is more likely a blur issue. As you make smaller apertures, youʻre using longer exposure times. SR on a tripod is going to cause sensor blur. If SR is off, we could help to trouble shoot if you could post examples with the EXIF files.

[JohnX]

Use kit on the tripod and operate using 2sec delay, which switches off SR.

Odd though that things are worse at 5.6, etc.

[robthebloke]

1. If you're on tripod, turn off shake reduction.
2. If you're hand holding, turn on shake reduction!
3. The DA* 300 is a lens that demands TAV mode. Set the shutter to be say 1/500 (less if you're brave!), and knock the exposure compensation down a bit (I usually use between -0.7ev, and -2.0ev in extreme cases). The biggest problem is maintaining a high enough shutter speed to get the shot. If it's underexposed (which is very common in the evenings and mornings), then you can usually pull a good looking image out of the shadows in Lightroom.
4. In some cases, spot based AF helps (e.g. Bird in a tree). In others cases you'd be better off using all focus points (e.g. Bird in flight). Set up a couple of user modes on the k-3 so you can quickly toggle between them.
5. Practice with the lens a *lot*. It's not the easiest lens to use on the k-3 (it's actually a lot easier to use on the k-1!). At first your hit rate will be bad (especially on overcast winter days). But it does get much easier on a bright sunny day! (I got mine in the Black Friday sales last year, in November, when it was bloody dark! The results weren't great. it was obviously good wide open, but it takes practice to get good results when stopped down - or bright sunshine!)

Great lens though! I just picked up the 200 to go with it (faster aperture, easier to use, but doesn't quite attain the level of the 300 imho!)

[UserAccessDenied]

1. If you're on tripod, turn off shake reduction.
2. If you're hand holding, turn on shake reduction!
3. The DA* 300 is a lens that demands TAV mode. Set the shutter to be say 1/500 (less if you're brave!), and knock the exposure compensation down a bit (I usually use between -0.7ev, and -2.0ev in extreme cases). The biggest problem is maintaining a high enough shutter speed to get the shot. If it's underexposed (which is very common in the evenings and mornings), then you can usually pull a good looking image out of the shadows in Lightroom.
4. In some cases, spot based AF helps (e.g. Bird in a tree). In others cases you'd be better off using all focus points (e.g. Bird in flight). Set up a couple of user modes on the k-3 so you can quickly toggle between them.
5. Practice with the lens a *lot*. It's not the easiest lens to use on the k-3 (it's actually a lot easier to use on the k-1!). At first your hit rate will be bad (especially on overcast winter days). But it does get much easier on a bright sunny day! (I got mine in the Black Friday sales last year, in November, when it was bloody dark! The results weren't great. it was obviously good wide open, but it takes practice to get good results when stopped down - or bright sunshine!)

Great lens though! I just picked up the 200 to go with it (faster aperture, easier to use, but doesn't quite attain the level of the 300 imho!)

Just to add to this:

I think @robthebloke nailed it...

Turn OFF shake reduction in general > even hand held I've noticed it will introduce motion blur when I use it on my K-3ii. Perhaps I have a very steady hand? idk, but that's just my experience with SR and the DA*300 on a K-3ii

Also I shoot in manual mode, so can't attest to the TAV mode - But I will say any shot under 1/450 is usually a throw away...
I usually say the shutter has to match the 35mm equivalent FL. So 1.5x 300 = 450. That's my starting point.

I also notice my K-3ii tends to overexpose images, so if the image looks dark on the post-shot preview, don't worry too much. I have noticed that most shots that are underexposed I can save in lightroom. Any overexposed shot is generally harder to fix - Again this is just my experience.

Focus and Metering I use single point spot.
Also use rear AF button and turn off half-press shutter focusing... This has helped IMMENSELY when it comes to nailing the focus on small objects in trees and even birds in flight! - Just keep your arms steady and pivot at the hips when tracking a bird in flight. Look at @Heie 's article (Making the Most of Long Exposure Handhelds - Introduction - In-Depth Articles) about keeping steady at low shutter speeds in the field without a tripod/monopod. That's a great article for learning new techniques. I tend to use the "elbows in, almost touching" approach when in low light and need to drop shutter speeds.

The best way to improve a skill is by failing.
Learn from your mistakes and adjust, modify, research.

I would wait for a sunny day and take some shots at ISO100, 1/1600 and F4; F5.6; F8; F11. Shoot from a tripod if you can, or try the elbow lock method in the article I reference above.
Check sharpness - and post photos here!

Cheers!
Logan

[DW58]

Thanks for all your replies. Between rains yesterday afternoon I played with it some more and am fairly certain it's operator error as sharpness was hit and miss throughout aperture range.
robthebloke's post especially helped with my state of mind. Thank you. Supposed to be nasty again today weather wise but will try everyone's suggestions first chance I get.
What a great forum this is.

[UserAccessDenied]

Thanks for all your replies. Between rains yesterday afternoon I played with it some more and am fairly certain it's operator error as sharpness was hit and miss throughout aperture range.
robthebloke's post especially helped with my state of mind. Thank you. Supposed to be nasty again today weather wise but will try everyone's suggestions first chance I get.
What a great forum this is.

It's a great camera and a spectacular lens!
Have fun!

Once you get the settings dialed in you're gonna have a blast with that combo...

It took me a few outings to get it just how I wanted it. Now that lens rarely leaves my K-3ii

[GeneV]

I would echo the suggestion to use TAV mode. I have that mode programmed into the K3 as part of my user setting for the DA*300 +TC. I use f/8 1/400 as my defaults. F/5.6 is actually the sharpest aperture according to tests, but with the Rear converter, that is now F/8. Normally I am hand holding so SR is on.

I also have one K3 dedicated to this lens.

[DW58]

Wow. Suggestions and words of encouragement keep rolling in. Thank you all!

[DW58]

Well I was supposed to be painting the bathroom but the sun came out so outside I went. Switched to TAv, 3 sec remote. Here's a cropped shot at f/6.3, 1/500, ISO 320. Tree about 20 ft away. Focus point on the lichen just to the right of the crotch of the tree. What a difference in the results I had yesterday. Going to check front/back focus but right now I need to start painting or Carol may have a few choice words for me. Thanks again for all your help and feel free to comment about the focus in this image.

[DW58]

This one tweaked a little more.