Recent content by heron_AI

I ordered it online because it's a long trip (it includes 5-6hrs on a ferry one way), so the only sensible thing to do is to send it via mail. It's so much cheaper than at the local stores. They actually had a discount on selected ART lenses during June so they were a lot cheaper than what can...

I can't make up my mind about this particular lens, should I send it back or not? I've seen people complaining about AF unreliability on the web, I'm afraid I will have to wait just to get another lens with similar issue. Here are two pictures, one sample image and one showing the settings I...

Yes, we have the same laws here.

From a local store in Finland. They don't seem to have customer service open at Saturdays.

Hmm.. well I might just do that. I don't trust the AF and it's more critical with such shallow DOF. I'm gonna talk to the seller on Monday.

Like dedicated contrast detect sites? On Nikon? I thought the camera evaluates the sensor data to determine which focus produces the image with the highest contrast. Anyway, I don't get the point of your post.

I asked him if he thought the lens was flawed, and he asked me if it focus correctly with live view - which it does - then the lens is ok. I have gone through a couple of iterations setting the tuning parameters and now I'm satisfied. At the longer focal distances the values are in the range of...

You're right. Just got off the phone with a service technician and I could send it in but then I would have to send the camera as well (for lens calibration). He did not think the lens is flawed, if it focus correctly with live view then the lens is ok. So I'm gonna get the af as good as...

I have done some more testing/calibrating of the four focal lengths in Sigma Optimization software (18, 24, 28 and 35) at ~2 meters. Noticed I couldn't get the parameters right and did some investigation. Turns out that the focus is different for ex. 24mm depending on whether I've been shooting...

Thank you. I have now e-mailed the seller and Sigma Finland for technical advice. Will update you on what the say.

If the problem was in the camera, then my other lenses would need calibration as well. I have a Sigma 150-600 C and I have scrutinized the AF with that lens thoroughly and it's absolutely dead on from factory. At one point I was considering an earlier version of Sigmas normal/wide zooms, but I...

Ok, thank you.

Got my new Sigma 18-35/F1.8 DC today and it didn't take long to notice that the AF was off. Luckily I have the Sigma USB Dock and I have started calibrating it (which is quite tedious), I have a few focal lengths at infinty left to do but the day light is fading. Anyway, AF is atleast, or near...

Indeed :)

Yes, as several of you have pointed out, it was heat haze that caused the blur. Took tack sharp pictures today. As wezza13 said, it's a bigger problem than I realized and it explains blurry pictures in the past (where I dismissed it as camera shake/out of focus). The blurring from heat/vapor...