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02-08-2018, 12:11 AM   #1
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Need help with 150-450 focusing issue

So I'm trying to figure out what's going on with my 150-450 lens. It's a little over a month old at this point, just for reference.

So I was out at the Falcon Heavy launch the other day. I was 3 miles out from the pad with a clear line of sight. However, no matter what I did, I could not get a good focus on the rocket or the pad. As you can see in my picture, there's a US flag on the rocket, a spacex logo as well as one on the water tower. I tried using autofocus, and no luck. Then I switched to manual focus and simply could not dial it in with the focus ring. I was zoomed in at 450mm, and shooting in crop mode on the k1

Does anyone have any idea what's going on? I can't say I've had any issues with the lens other than this. I've used it with wildlife at 450mm (although not in crop mode) with success. I'm slightly worried that I may have a bad copy of the lens now. Not ruling out operator error here, but I have no idea where to start.

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02-08-2018, 12:24 AM   #2
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Was it hot that day? At the distances you were shooting, if it is a hot day, everything will be distorted.

Were you in a vehicle, air conditioned, hot outside? More distortion.

Were you on a tripod? Try the electronic shutter.

It looks to me like movement blur or heat distortion
02-08-2018, 12:26 AM   #3
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Three miles is a pretty good stretch to be shooting across. My initial thought is humidity and moisture in the air were affecting your ability to achieve tack sharp focus you were looking for.
02-08-2018, 12:28 AM   #4
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Hi Michael, a couple of questions, hand-held or tripod, and do you have the EXIF data so the members can see your settings?


EDIT - And yes, as the others have mentioned, heat haze is a real possibility.


Last edited by Unregistered User 8; 02-08-2018 at 12:39 AM.
02-08-2018, 12:41 AM   #5
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Can we see the settings used please, its a big heavy lens and I'm pretty good at handholding down to really low speeds, but not with this beastie.
02-08-2018, 01:15 AM   #6
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EXIF data attached.

Yes, it was hazy outside, but both my friends with their respective telephotos didn't seem to have the same issue I did, and we were all standing next to each other.

Camera was tripod mounted on the ground, with the tripod attached to the foot on the lens
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02-08-2018, 01:19 AM   #7
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Being that the camera was tripod mounted, was the camera SR turned off Michael?

02-08-2018, 01:49 AM   #8
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QuoteOriginally posted by pjv Quote
Being that the camera was tripod mounted, was the camera SR turned off Michael?
I assume you mean shake reduction by that? (Not familiar with the acronym). If so, then no. I never tend to mess with that even when i tripod mount.
02-08-2018, 01:59 AM   #9
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QuoteOriginally posted by motorhead9999 Quote
I assume you mean shake reduction by that? (Not familiar with the acronym). If so, then no. I never tend to mess with that even when i tripod mount.
It is recommended in the manual(s) to turn off SR ( shake reduction ) when the camera is tripod mounted. There are many threads detailing the " why's " on the forums, but this could be your issue - some will disagree !! Good luck, and I hope you get to the bottom of your problem.
02-08-2018, 02:09 AM   #10
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Hi Michael... Did you have a filter attached to the lens? If so, what type / make / model?
02-08-2018, 02:54 AM   #11
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I have/had this same issue with the K3-II + DA*60-250 and the 1.4TC when focusing near infinity this summer. Tested now again in the winter and everything seemed to be fine. But last summer I noticed I could not for the life of me, get things that are far away to focus properly (airplanes, birds flying high etc). Everything 100ft and in is perfectly in focus. Sadly I can't tell much more about this because I haven't had much chance to use this combo. I just recalled one day that I could not get a rabbit on a clear field to get in focus, and I have never had this issue before.
To this day I do not know what it is and whether I'm just imagining things. Will wait for the weather to get better and do some proper testing again.
02-08-2018, 04:32 AM   #12
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QuoteOriginally posted by BigMackCam Quote
Hi Michael... Did you have a filter attached to the lens? If so, what type / make / model?

Nope. I didn't have a filter on the lens.
02-08-2018, 04:37 AM   #13
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QuoteOriginally posted by motorhead9999 Quote
Nope. I didn't have a filter on the lens.
OK... always worth checking

If you have time, might you be able to provide a 1:1 (i.e. 100%) crop of a small area - perhaps the legs of that tower to the left of the craft?
02-08-2018, 05:20 AM   #14
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my WAG would be motion blur as well as heat distortion

possible shock wave from the actual launch??

no idea how long the shock wave would take to reach your position

how well built is your tripod, you are supporting a lot of weight with the camera and lens

lots of heat being generated at the time of the shutter being triggered

were you using a shuttle delay and/or remote shutter trigger mechanism

problem with most of this possible explanation is that you say others didn't have the problem

Last edited by aslyfox; 02-08-2018 at 12:30 PM.
02-08-2018, 05:29 AM   #15
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I've had very similar distortions shooting across a river I live next to that were atmospheric. You say the others you were shooting with didn't have this issue. Was that based on what you all were seeing that day while shooting or their final pictures too? Also, I think there's a good chance the SR is at play too. A little different scenario, but with that lens on my K3II, shooting the sun through a solar filter with SR on, my K3II started to shake to the point you could feel and hear it. Camera couldn't figure out what it was getting a fix on and went nuts. Turned the SR off, and all good. I'd recommend some more test shots with SR off as a start.
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