De-centered element? Nope - but what should I expect from the DFA 150-450

**simple1** · 01-12-2020, 07:06 PM

Originally posted by rogerstg

Based on all you've done, I tend to agree. Hope you can exchange it.

Thanks Roger. RMA is approved and it’s boxed to ship back.

robiles · 01-13-2020, 05:05 AM

Originally posted by simple1

bracketing on KP only does full stops as far as I can tell)!

Have you tried rotating the back wheel? On my KP the back wheel you set the ev value (1/3 stops - might have to be set up in the custom menu, but i am not sure), and front wheel the nr of bracketed shots (posibility: 2, 3 and 5 shots)

**simple1** · 01-13-2020, 05:10 AM

Originally posted by robiles

Have you tried rotating the back wheel? On my KP the back wheel you set the ev value (1/3 stops - might have to be set up in the custom menu, but i am not sure), and front wheel the nr of bracketed shots (posibility: 2, 3 and 5 shots)

In the custom menu I set to - 0 1
From the info menu I could set the values with the back dial (+/- 1,2,3...). I’ll play around a bit more as no doubt I overlooked something.

Thanks

robiles · 01-13-2020, 05:43 AM

Originally posted by simple1

In the custom menu I set to - 0 1
From the info menu I could set the values with the back dial (+/- 1,2,3...). I’ll play around a bit more as no doubt I overlooked something.

Thanks

You set the ev bracket values while you are selecting the shooting mode. After pushing the right arrow and selecting auto bracketing, you rotate the two wheels to set the desired values, and only then the ok button. Hope this works.

**simple1** · 01-13-2020, 05:51 AM

Originally posted by robiles

You set the ev bracket values while you are selecting the shooting mode. After pushing the right arrow and selecting auto bracketing, you rotate the two wheels to set the desired values, and only then the ok button. Hope this works.

Interesting - on the 150-450 it would only do full stops. On the 55-300 it does 1/3 stops.

**Serkevan** · 01-13-2020, 07:00 AM

Originally posted by simple1

These are also 200% crop. First image is f5.6, second is f7.1. f5.6 is noticeably softer. Shutter speed for both is 1/800s. Not that I'd crop at 200%, it just better highlights the difference in IQ.

The top one has a lot of noticeable motion blur; either the bird was moving very quickly or (more likely) there was a small vibration in the camera? Maybe wind or so.

**simple1** · 01-13-2020, 02:08 PM

Originally posted by Serkevan

The top one has a lot of noticeable motion blur; either the bird was moving very quickly or (more likely) there was a small vibration in the camera? Maybe wind or so.

I'll admit I wouldn't know motion blur if it slapped me in the face

Before I decided to RMA the lens I did some various test shots on stationary objects with a tripod.

Here is a sample

f/5.6

f/8.0

f5.6-7.1 just don't resolve the detail, 8-9 are good, and starts dropping off again at f10.
I get that the difference is small, but it is noticeable at normal viewing resolution. It's the difference between great detail on an owl's eye or just kind of muddy looking. And yes I could stop down but for a lens that cost as much as this I don't think I should need to, that's a full stop I'm effectively losing.
Just my perspective and I get that some would disagree.

Appreciate the input!

**Serkevan** · 01-13-2020, 02:49 PM

Okay, now it looks more like either front focusing or just too much cropping. Can you show the full image?

**simple1** · 01-13-2020, 04:54 PM

Originally posted by Serkevan

Okay, now it looks more like either front focusing or just too much cropping. Can you show the full image?

Oh...it's definitely too much crop, that's a 200% crop. Point was to emphasize the difference between f5.6 and f8.

**rogerstg** · 01-13-2020, 06:26 PM

Originally posted by simple1

Oh...it's definitely too much crop, that's a 200% crop. Point was to emphasize the difference between f5.6 and f8.

If those pics of the post and wire are 200%, IMO the ƒ5.6 is not bad, and much, much better than the ƒ5.6 bird photo.

**simple1** · 01-14-2020, 06:38 AM

Originally posted by rogerstg

If those pics of the post and wire are 200%, IMO the ƒ5.6 is not bad, and much, much better than the ƒ5.6 bird photo.

Got it.
Reckon my expectations were a bit off.

Thanks again.

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01-12-2020, 07:06 PM	#16
simple1 Loyal Site Supporter Join Date: Dec 2009 Location: In the Florida swamps Posts: 761 Original Poster	Originally posted by rogerstg Based on all you've done, I tend to agree. Hope you can exchange it. Thanks Roger. RMA is approved and it’s boxed to ship back.

01-13-2020, 05:05 AM	#17
robiles Veteran Member Join Date: Jan 2014 Location: Deva Posts: 311	Originally posted by simple1 bracketing on KP only does full stops as far as I can tell)! Have you tried rotating the back wheel? On my KP the back wheel you set the ev value (1/3 stops - might have to be set up in the custom menu, but i am not sure), and front wheel the nr of bracketed shots (posibility: 2, 3 and 5 shots)

01-13-2020, 05:10 AM	#18
simple1 Loyal Site Supporter Join Date: Dec 2009 Location: In the Florida swamps Posts: 761 Original Poster	Originally posted by robiles Have you tried rotating the back wheel? On my KP the back wheel you set the ev value (1/3 stops - might have to be set up in the custom menu, but i am not sure), and front wheel the nr of bracketed shots (posibility: 2, 3 and 5 shots) In the custom menu I set to - 0 1 From the info menu I could set the values with the back dial (+/- 1,2,3...). I’ll play around a bit more as no doubt I overlooked something. Thanks

01-13-2020, 05:43 AM	#19
robiles Veteran Member Join Date: Jan 2014 Location: Deva Posts: 311	Originally posted by simple1 In the custom menu I set to - 0 1 From the info menu I could set the values with the back dial (+/- 1,2,3...). I’ll play around a bit more as no doubt I overlooked something. Thanks You set the ev bracket values while you are selecting the shooting mode. After pushing the right arrow and selecting auto bracketing, you rotate the two wheels to set the desired values, and only then the ok button. Hope this works.

01-13-2020, 05:51 AM	#20
simple1 Loyal Site Supporter Join Date: Dec 2009 Location: In the Florida swamps Posts: 761 Original Poster	Originally posted by robiles You set the ev bracket values while you are selecting the shooting mode. After pushing the right arrow and selecting auto bracketing, you rotate the two wheels to set the desired values, and only then the ok button. Hope this works. Interesting - on the 150-450 it would only do full stops. On the 55-300 it does 1/3 stops.

01-13-2020, 07:00 AM	#21
Serkevan Site Supporter Join Date: May 2019 Photos: Albums Posts: 5,976	Originally posted by simple1 These are also 200% crop. First image is f5.6, second is f7.1. f5.6 is noticeably softer. Shutter speed for both is 1/800s. Not that I'd crop at 200%, it just better highlights the difference in IQ. The top one has a lot of noticeable motion blur; either the bird was moving very quickly or (more likely) there was a small vibration in the camera? Maybe wind or so.

01-13-2020, 02:08 PM	#22
simple1 Loyal Site Supporter Join Date: Dec 2009 Location: In the Florida swamps Posts: 761 Original Poster	Originally posted by Serkevan The top one has a lot of noticeable motion blur; either the bird was moving very quickly or (more likely) there was a small vibration in the camera? Maybe wind or so. I'll admit I wouldn't know motion blur if it slapped me in the face Before I decided to RMA the lens I did some various test shots on stationary objects with a tripod. Here is a sample f/5.6 f/8.0 f5.6-7.1 just don't resolve the detail, 8-9 are good, and starts dropping off again at f10. I get that the difference is small, but it is noticeable at normal viewing resolution. It's the difference between great detail on an owl's eye or just kind of muddy looking. And yes I could stop down but for a lens that cost as much as this I don't think I should need to, that's a full stop I'm effectively losing. Just my perspective and I get that some would disagree. Appreciate the input!

01-13-2020, 02:49 PM	#23
Serkevan Site Supporter Join Date: May 2019 Photos: Albums Posts: 5,976	Okay, now it looks more like either front focusing or just too much cropping. Can you show the full image?

01-13-2020, 04:54 PM	#24
simple1 Loyal Site Supporter Join Date: Dec 2009 Location: In the Florida swamps Posts: 761 Original Poster	Originally posted by Serkevan Okay, now it looks more like either front focusing or just too much cropping. Can you show the full image? Oh...it's definitely too much crop, that's a 200% crop. Point was to emphasize the difference between f5.6 and f8.

01-13-2020, 06:26 PM	#25
rogerstg Loyal Site Supporter Join Date: Oct 2007 Location: Rhode Island Photos: Albums Posts: 1,168	Originally posted by simple1 Oh...it's definitely too much crop, that's a 200% crop. Point was to emphasize the difference between f5.6 and f8. If those pics of the post and wire are 200%, IMO the ƒ5.6 is not bad, and much, much better than the ƒ5.6 bird photo.

01-14-2020, 06:38 AM	#26
simple1 Loyal Site Supporter Join Date: Dec 2009 Location: In the Florida swamps Posts: 761 Original Poster	Originally posted by rogerstg If those pics of the post and wire are 200%, IMO the ƒ5.6 is not bad, and much, much better than the ƒ5.6 bird photo. Got it. Reckon my expectations were a bit off. Thanks again.