A Photography forum. PhotoBanter.com

If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below.

Go Back   Home » PhotoBanter.com forum » Digital Photography » Digital Photography
Site Map Home Register Authors List Search Today's Posts Mark Forums Read Web Partners

D750 -CRASH- and subsequent testing.



 
 
Thread Tools Display Modes
  #11  
Old August 10th 16, 04:13 AM posted to rec.photo.digital
Eric Stevens
external usenet poster
 
Posts: 13,611
Default D750 -CRASH- and subsequent testing.

On Tue, 9 Aug 2016 16:34:12 -0700 (PDT), RichA
wrote:

On Tuesday, 12 July 2016 23:31:23 UTC-4, Eric Stevens wrote:
A few months ago I had a fall while carrying my camera. I came down
hard but the camera which I was carrying came down even harder on
concrete. It was a hell of an whack. I think the Manfrotto tripod shoe
on the bottom took the bulk of the impact. RichA will no doubt be
disappointed to learn that all those fancy carbon-fibre parts on the
body of the camera remained intact as did the magnesium metal frame.


How hard could the impact have been if the camera sustained no damage, not even a dent or ding? I dropped a specialized tripod the other day onto hardwood. The head of the tripod which was held in-place with 3 small allen-head set-screws rotated slightly to the point where the allen screw channels (in aluminum) were bent sideways, ruining the threading so I have to re-tap the holes and put in slightly larger screws to fix the problem. The tripod weighs about 20lbs.


The camera was in my hand which I shot out to try and break the fall.
I remeber the sensation: the tripod shoe crunching grit as I came
down. As I said, it was a hell of a whack.
--

Regards,

Eric Stevens
  #12  
Old August 10th 16, 04:32 AM posted to rec.photo.digital
Bill W
external usenet poster
 
Posts: 1,692
Default D750 -CRASH- and subsequent testing.

On Wed, 10 Aug 2016 10:06:35 +1200, Eric Stevens
wrote:

On Tue, 12 Jul 2016 21:01:45 -0700, Bill W
wrote:

On Wed, 13 Jul 2016 15:31:25 +1200, Eric Stevens
wrote:

A few months ago I had a fall while carrying my camera. I came down
hard but the camera which I was carrying came down even harder on
concrete. It was a hell of an whack. I think the Manfrotto tripod shoe
on the bottom took the bulk of the impact. RichA will no doubt be
disappointed to learn that all those fancy carbon-fibre parts on the
body of the camera remained intact as did the magnesium metal frame.

All of the body of the camera has continued to function properly since
the fall but I have had doubts about Tamron 24-70 f/2.8 lens with
which it fas fitted at the time. I have had no worries about its
mechanical functioning but I was concerned that the impact may have
displaced or distorted key parts of the lens' internal mechanism.

I have just put the lens through a series of primitive tests to see
how well it is working optically. AF fine tuning (focus calibration)
has ended up at +1 which would be quite acceptable in a new lens, so
no worries there. I was more concerned about sharpness and definition.
I made a panel of a number of fine-detailed objects and made a number
of test shots. A jpg of one of these may be found at
https://dl.dropboxusercontent.com/u/...R--7502179.jpg
This shot and the versions below were all made at 24mm, f/2.8 and a
distance of about 4' (1.2m). Focussing was autofocus.

Not being satisfied with the relatively coarse screen resolution for a
24MP image I also made an image for 100% printing of an A2 sized
image. Those game enough to take on 244MB file can find it at
https://dl.dropboxusercontent.com/u/...R--7502179.tif

These images are straight off the camera via LR and the only
processing is correction of lens distortion. I would be grateful for
any comments on the quality of the image. Is it what one would expect
from that camera and lens combination?

For those interested the original raw file, it may be found at
https://dl.dropboxusercontent.com/u/...3/_7502179.NEF

I must add, I was not responsible for emptying all those bottles.


A friend dropped his FF Nikon, and said it sounded like an eggshell
when it hit the ground. His crack was visible, but you might have one
that's not. He said the IQ was off after that, and I think he gave up
on the camera. Bodies were not available at the time.

I offered him $100. I figure I can fix anything, but he declined.

Anyway, you might want to send/take it in to get checked. We all know
how critical dimensions are in those things.


After reading allresponses I decided to send the lens in for testing.
I have just received an account by email which among other things
says:

"Dismanted lens. Supplied and fitted new front cam barrel and
rollers. These were stretched causing optics to mis-align.
Reassembled, recalibrated lens and checked."

I was right: it wasn't working properly although there was nothing
obvious I could put my finger on. The bottles are still set up in my
room and I will be interested to compare results whan the lens
returns.


I'm surprised you didn't have the camera checked, too. If you still
think there's a problem, there are some critical angles/distances
involved in the PDAF. But I think that if there is a problem with
that, you will have OoF problems across the entire image in every
shot. In fact, if your PDAF shots are as good as your CDAF shots, you
are probably good to go.
  #13  
Old August 10th 16, 10:02 AM posted to rec.photo.digital
Eric Stevens
external usenet poster
 
Posts: 13,611
Default D750 -CRASH- and subsequent testing.

On Tue, 09 Aug 2016 20:32:09 -0700, Bill W
wrote:

On Wed, 10 Aug 2016 10:06:35 +1200, Eric Stevens
wrote:

On Tue, 12 Jul 2016 21:01:45 -0700, Bill W
wrote:

On Wed, 13 Jul 2016 15:31:25 +1200, Eric Stevens
wrote:

A few months ago I had a fall while carrying my camera. I came down
hard but the camera which I was carrying came down even harder on
concrete. It was a hell of an whack. I think the Manfrotto tripod shoe
on the bottom took the bulk of the impact. RichA will no doubt be
disappointed to learn that all those fancy carbon-fibre parts on the
body of the camera remained intact as did the magnesium metal frame.

All of the body of the camera has continued to function properly since
the fall but I have had doubts about Tamron 24-70 f/2.8 lens with
which it fas fitted at the time. I have had no worries about its
mechanical functioning but I was concerned that the impact may have
displaced or distorted key parts of the lens' internal mechanism.

I have just put the lens through a series of primitive tests to see
how well it is working optically. AF fine tuning (focus calibration)
has ended up at +1 which would be quite acceptable in a new lens, so
no worries there. I was more concerned about sharpness and definition.
I made a panel of a number of fine-detailed objects and made a number
of test shots. A jpg of one of these may be found at
https://dl.dropboxusercontent.com/u/...R--7502179.jpg
This shot and the versions below were all made at 24mm, f/2.8 and a
distance of about 4' (1.2m). Focussing was autofocus.

Not being satisfied with the relatively coarse screen resolution for a
24MP image I also made an image for 100% printing of an A2 sized
image. Those game enough to take on 244MB file can find it at
https://dl.dropboxusercontent.com/u/...R--7502179.tif

These images are straight off the camera via LR and the only
processing is correction of lens distortion. I would be grateful for
any comments on the quality of the image. Is it what one would expect
from that camera and lens combination?

For those interested the original raw file, it may be found at
https://dl.dropboxusercontent.com/u/...3/_7502179.NEF

I must add, I was not responsible for emptying all those bottles.

A friend dropped his FF Nikon, and said it sounded like an eggshell
when it hit the ground. His crack was visible, but you might have one
that's not. He said the IQ was off after that, and I think he gave up
on the camera. Bodies were not available at the time.

I offered him $100. I figure I can fix anything, but he declined.

Anyway, you might want to send/take it in to get checked. We all know
how critical dimensions are in those things.


After reading allresponses I decided to send the lens in for testing.
I have just received an account by email which among other things
says:

"Dismanted lens. Supplied and fitted new front cam barrel and
rollers. These were stretched causing optics to mis-align.
Reassembled, recalibrated lens and checked."

I was right: it wasn't working properly although there was nothing
obvious I could put my finger on. The bottles are still set up in my
room and I will be interested to compare results whan the lens
returns.


I'm surprised you didn't have the camera checked, too. If you still
think there's a problem, there are some critical angles/distances
involved in the PDAF. But I think that if there is a problem with
that, you will have OoF problems across the entire image in every
shot. In fact, if your PDAF shots are as good as your CDAF shots, you
are probably good to go.


PDAF? CDAF? What are you talking about?
--

Regards,

Eric Stevens
  #14  
Old August 10th 16, 02:34 PM posted to rec.photo.digital
nospam
external usenet poster
 
Posts: 24,165
Default D750 -CRASH- and subsequent testing.

In article , Eric Stevens
wrote:


I'm surprised you didn't have the camera checked, too. If you still
think there's a problem, there are some critical angles/distances
involved in the PDAF. But I think that if there is a problem with
that, you will have OoF problems across the entire image in every
shot. In fact, if your PDAF shots are as good as your CDAF shots, you
are probably good to go.


PDAF? CDAF? What are you talking about?


phase detect and contrast detect autofocus.
  #15  
Old August 10th 16, 09:44 PM posted to rec.photo.digital
Eric Stevens
external usenet poster
 
Posts: 13,611
Default D750 -CRASH- and subsequent testing.

On Wed, 10 Aug 2016 09:34:23 -0400, nospam
wrote:

In article , Eric Stevens
wrote:


I'm surprised you didn't have the camera checked, too. If you still
think there's a problem, there are some critical angles/distances
involved in the PDAF. But I think that if there is a problem with
that, you will have OoF problems across the entire image in every
shot. In fact, if your PDAF shots are as good as your CDAF shots, you
are probably good to go.


PDAF? CDAF? What are you talking about?


phase detect and contrast detect autofocus.


I checked focus before I sent the lens away. I eventually made an
adjustment of +1. That suggests that everything is in it its correct
place.
--

Regards,

Eric Stevens
  #16  
Old August 11th 16, 01:36 AM posted to rec.photo.digital
Bill W
external usenet poster
 
Posts: 1,692
Default D750 -CRASH- and subsequent testing.

On Thu, 11 Aug 2016 08:44:20 +1200, Eric Stevens
wrote:

On Wed, 10 Aug 2016 09:34:23 -0400, nospam
wrote:

In article , Eric Stevens
wrote:


I'm surprised you didn't have the camera checked, too. If you still
think there's a problem, there are some critical angles/distances
involved in the PDAF. But I think that if there is a problem with
that, you will have OoF problems across the entire image in every
shot. In fact, if your PDAF shots are as good as your CDAF shots, you
are probably good to go.

PDAF? CDAF? What are you talking about?


phase detect and contrast detect autofocus.


I checked focus before I sent the lens away. I eventually made an
adjustment of +1. That suggests that everything is in it its correct
place.


It's likely enough, and you'll be sure after the lens comes back. BTW,
CDAF is what's used in live view.
 




Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is Off
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
crash Savageduck[_3_] Digital Photography 26 July 27th 10 11:55 AM
crash Savageduck[_3_] Digital Photography 0 July 26th 10 08:17 AM
DPP crash with 40D CRWs ? Focus Digital SLR Cameras 8 May 3rd 08 03:54 PM
compact CRASH stevo Digital Photography 9 September 16th 06 03:33 AM
// Cutouts can crash Qimage. REPEATABLE. // RickTrelles Digital Photography 2 June 12th 06 04:36 PM


All times are GMT +1. The time now is 09:25 AM.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 PhotoBanter.com.
The comments are property of their posters.