At full tele and near infinity focus issue..

Steven Thomas · April 8th, 2008, 08:17 PM

Ok,
Here's some images displaying the far focus issue at full tele.

I'd like to thank Maxim from Aerialsfilm for hosting these images.

My wife and step son against a wall ( same focal plane).
f1.9
focus distance 60ft
http://www.aerialsfilm.com/stevet/Im...e_wife_son.jpg

can't remember the exact fstop, but probably between f1.9 - f4.
focus distance ~125ft
http://www.aerialsfilm.com/stevet/Im... full tele.jpg

can't remember the exact fstop, but probably between f1.9 - f4.
focus distance ~100ft
http://www.aerialsfilm.com/stevet/Im...lake_ducks.jpg

f1.9
focus distance 30 ft.
http://www.aerialsfilm.com/stevet/Im...ele_ground.jpg

Eric Pascarelli · April 9th, 2008, 12:09 AM

Steven - I think I'm seeing softening on both sides (I'll check it in Photoshop).

Could you try putting a focus chart on the wall and panning it to either side and the middle of frame? This is a good way to compare sharpness of the different parts of the image.

Piotr Wozniacki · April 9th, 2008, 12:53 AM

Steven, no offence, but to me everything looks a bit soft in these grabs (both sides, and the middle as well). I'm not saying the problem doesn't exists, but to illustrate it a focus chart or something similar would be better, like Eric said.

Steven Thomas · April 9th, 2008, 06:40 AM

No offense taken,but,

You need to pull up:

http://www.aerialsfilm.com/stevet/Im...ull%20tele.jpg

It's a 1920x1080 image, so open the image full frame.
Look at the guy fishing and compare to the guy with the girl on the right.
Look down at the rocks and grass. They are at the same focal plane across the frame.

There's a dramatic difference here and is real obvious on a 24" monitor.
In fact, this is the first shot we looked at after running some RED tests.
We both went... what the heck is that...
If you can not see a difference between the middle of the screen and right side,
maybe there's something wrong with your monitor?

Also, like I've been mentioning in this thread, the problem is when the EX1 is at or near full tele AND focusing on distant objects (over 25 feet).

I plan on setting up a rez test, but I know the issue is shown at far focus.
I may set the chart up at as far a distance as I can and still be able to frame it.

BTW, I do not use detail ON, therefore, the overall shots may appear a bit soft.

I'm not sure the about the turn on point for this issue, but it was not there in previous work.
We do event work and we rely on a lot of tele shots. I've only had this camera since the end of January.

Alexander Kubalsky · April 9th, 2008, 07:08 AM

I couldn't really see anything so I checked it out in photoshop and cropped it, put a line through roughly where it starts to blur.

You mentioned you had different results on different days, could that just be humidity in the air? Smear on the lens? Sorry if that seems naive. Don't know much about lenses.

Bob Grant · April 9th, 2008, 07:48 AM

It doesn't look like an optical problem to my eyes. The guys with the fishing rod's shirt has a lot of red in it too. Could this be a problem with IR contamination, at least in part?

None of the posted images look exactly in focus anywhere in the frame. I know at the long end of the focal range zooms at this price point mightn't be that great but I'd expect better than that. At the same time there's atmospheric effects to consider, the slightest heat shimmer can play havoc with mpeg encoding as well as distort the image.

Just for a test that I'm far from certain what it means I dropped out the red channel in PS and converted to greyscale, seems to look much better. That may backup my IR theory.

Daniel Epstein · April 9th, 2008, 08:08 AM

If you are shooting with wide open Iris at Full Telephoto you are going to see all sorts of focus issues with many lenses. Try doing the same shots with and without the ND at different F Stops and see if the problem is triggered at a particular setting. Many lenses get very soft at the Telephoto end.

Steven Thomas · April 9th, 2008, 08:10 AM

I can't disagree at all regarding IR, but there's a distict difference with focal plane from center to edge. This particular shot was white balance set about 6300. It's was on the warm side. I set it to this setting to match the RED ONE setting.

The RED also has the IR issue, but his same shot is far better for focus deviation across the image. I can find out what he was using for a lens, but it was not anything special.

Regardless, I'm seeing the right side of the image fall off for focus. It's happening in ALL my shot on the tele end focusing at 25 feet or more.

It was not there before, I have 40 foot zoom shots that look great edge to edge taken outside in sunny AZ.

I will be performing rez chart tests at different focal distances. Unfortunately, the EX1 I would be able to compare will be in Portland OR for a month.

Piotr Wozniacki · April 9th, 2008, 08:28 AM

I wonder what kind of new issues are going to appear with us in the Northern hemisphere when the hot summer comes (so far, most of us have been beta-testing the EX1 for Sony Corporation in rather low temperatures).

;)

Steven Thomas · April 9th, 2008, 08:32 AM

I know Dan,
the far bank shot was probably close to f4.

I'll try more tests, but yesterday I saw the same thing at f4 at 30 feet.

Also, when I'm shooting f1.9, full zoom tele and focus at 20 feet or less, it looks great.

Paul Curtis · April 9th, 2008, 09:12 AM

Doesnt the EX have CAC (chromatic aberration correction) built in. Is there a chance that this isn't working in these cases.

I remember ages ago on this forum a test movie that showed that if you're zooming then the CAC doesn't kick in until you stop and you can see a definate sharpening of the image when it does.

So with these tests have you tried slowly zooming then stopping and looking at the zoom portion and the static portion and see if the issues are the same in both. If they are then it could be that somehow the CAC is off.

It does look like both sides are soft but not just that but it looks more like CA than general softness, although that's difficult to judge.

just a thought..
paul

Steven Thomas · April 9th, 2008, 10:40 AM

Paul, that's not a bad idea about checking slow zoom movement compared to the static image.

Having said that, I never really looked at the difference of CA zooming verses not, so I'm not sure if I have a reference to determine if CAC is working or not.

Yes, both sides are soft, but the right side shows more CA and is more out of focus.

After we spotted this issue and compare the RED frame against the EX1, I called up my wife who's not a camera tech.

We asked her what she thought might be wrong with the fishing image. She said the right side looked burry. It's true the left is soft too, but I'm not sure if that may not be normal for that particular zoom shot.

I'll know a lot more when I get a chance to do the rez tests at different distances.

Paul Curtis · April 9th, 2008, 11:13 AM

Im looking through a load of footage now. i have some stuff at full telephoto but probably not at infinity. I don't see *anything* like this on any footage shot over the past 4 weeks (and we have around 3 hours of drama shot all over the place INT and EXT). I will try and wave the camera outside and take a look later or tomorrow.

I've been shooting with no detail and as little enhancing on as possible, whether that makes a difference im not sure.

Have you been doing the back focus adjustment? I wonder if there's a chance that can screw up the CAC. Or whether something is set incorrectly when moving between full MF and Auto. I've definately had a couple of moments where something hasn't engaged quite right.

Have you tried adjusting the images in photoshop - scaling the channels differently to see if that clears up the aberrations? At least it would indicate that it is a lens aberration problem, not focus strictly speaking.

cheers
paul

Steven Thomas · April 9th, 2008, 12:04 PM

I'm going to test more on Friday morning.

All of my tests have confirmed that it's worse than it was two weeks ago, that's for sure.

Sony had me perform a camera reset (for giggles) and test it again.

They want me to send it in. My back focus is a tad softm(not that bad). I have never performed the BF adjustment myself on the EX1. They want to upgrade to software 1.05 and go through all the camera checks.

I plan on shooting rez charts at different distances and apetures and will include these images when I return it.

Keith Moreau · April 9th, 2008, 01:48 PM

I think I'm seeing this on my EX1 as well. I noticed an overall softness with my unit which surprised me, so I proceeded to do the backfocus adjustment, which seems to have improved the overall clarity of my unit. In my tests, however, with the lens completely open, I focused to infinity to about 1/2 mile to a mile away. This was a pretty hot day with visible heat waves coming from the ground. I've attached a frame grab of this.

I was puzzled when the right side of the image appeared more smeared the the left side. I attributed this to CA, but it was more pronounced on the right side than the left, in my opinion.

I also have a Letus Extreme, and the GG image isn't completely centered and Letus said it might be because the sensor isn't exactly centered. I'm wondering if the sensor isn't centered in the middle of the lens how anything can really be uniform with regard to focusing.

However overall I'm still pretty happy with the EX1. If anybody out there thinks I should send the unit in for repair I'd like your opinion.

-Keith

April 9th, 2008, 12:53 AM	#18
Piotr Wozniacki Inner Circle Join Date: Aug 2006 Location: Poland Posts: 4,086	Steven, no offence, but to me everything looks a bit soft in these grabs (both sides, and the middle as well). I'm not saying the problem doesn't exists, but to illustrate it a focus chart or something similar would be better, like Eric said. __________________ Sony PXW-FS7 \| DaVinci Resolve Studio; Magix Vegas Pro; i7-5960X CPU; 64 GB RAM; 2x GTX 1080 8GB GPU; Decklink 4K Extreme 12G; 4x 3TB WD Black in RAID 0; 1TB M.2 NVMe cache drive

April 9th, 2008, 07:08 AM	#20
Alexander Kubalsky Regular Crew Join Date: Jan 2008 Location: Japan Posts: 172	I couldn't really see anything so I checked it out in photoshop and cropped it, put a line through roughly where it starts to blur. You mentioned you had different results on different days, could that just be humidity in the air? Smear on the lens? Sorry if that seems naive. Don't know much about lenses. Attached Thumbnails

April 9th, 2008, 07:48 AM	#21
Bob Grant Trustee Join Date: Nov 2005 Location: Sydney Australia Posts: 1,570	It doesn't look like an optical problem to my eyes. The guys with the fishing rod's shirt has a lot of red in it too. Could this be a problem with IR contamination, at least in part? None of the posted images look exactly in focus anywhere in the frame. I know at the long end of the focal range zooms at this price point mightn't be that great but I'd expect better than that. At the same time there's atmospheric effects to consider, the slightest heat shimmer can play havoc with mpeg encoding as well as distort the image. Just for a test that I'm far from certain what it means I dropped out the red channel in PS and converted to greyscale, seems to look much better. That may backup my IR theory. Attached Thumbnails

April 9th, 2008, 08:28 AM	#24
Piotr Wozniacki Inner Circle Join Date: Aug 2006 Location: Poland Posts: 4,086	I wonder what kind of new issues are going to appear with us in the Northern hemisphere when the hot summer comes (so far, most of us have been beta-testing the EX1 for Sony Corporation in rather low temperatures). ;) __________________ Sony PXW-FS7 \| DaVinci Resolve Studio; Magix Vegas Pro; i7-5960X CPU; 64 GB RAM; 2x GTX 1080 8GB GPU; Decklink 4K Extreme 12G; 4x 3TB WD Black in RAID 0; 1TB M.2 NVMe cache drive

April 9th, 2008, 01:48 PM	#30
Keith Moreau Major Player Join Date: Nov 2006 Location: Brisbane, California Posts: 530	I think I'm seeing this on my EX1 as well. I noticed an overall softness with my unit which surprised me, so I proceeded to do the backfocus adjustment, which seems to have improved the overall clarity of my unit. In my tests, however, with the lens completely open, I focused to infinity to about 1/2 mile to a mile away. This was a pretty hot day with visible heat waves coming from the ground. I've attached a frame grab of this. I was puzzled when the right side of the image appeared more smeared the the left side. I attributed this to CA, but it was more pronounced on the right side than the left, in my opinion. I also have a Letus Extreme, and the GG image isn't completely centered and Letus said it might be because the sensor isn't exactly centered. I'm wondering if the sensor isn't centered in the middle of the lens how anything can really be uniform with regard to focusing. However overall I'm still pretty happy with the EX1. If anybody out there thinks I should send the unit in for repair I'd like your opinion. -Keith Attached Thumbnails

April 8th, 2008, 08:17 PM	#16
Steven Thomas Trustee Join Date: Sep 2005 Location: Gilbert, AZ Posts: 1,896	Ok, Here's some images displaying the far focus issue at full tele. I'd like to thank Maxim from Aerialsfilm for hosting these images. My wife and step son against a wall ( same focal plane). f1.9 focus distance 60ft http://www.aerialsfilm.com/stevet/Im...e_wife_son.jpg can't remember the exact fstop, but probably between f1.9 - f4. focus distance ~125ft http://www.aerialsfilm.com/stevet/Im... full tele.jpg can't remember the exact fstop, but probably between f1.9 - f4. focus distance ~100ft http://www.aerialsfilm.com/stevet/Im...lake_ducks.jpg f1.9 focus distance 30 ft. http://www.aerialsfilm.com/stevet/Im...ele_ground.jpg

April 9th, 2008, 12:09 AM	#17
Eric Pascarelli Major Player Join Date: Nov 2007 Location: Los Angeles, CA Posts: 498	Steven - I think I'm seeing softening on both sides (I'll check it in Photoshop). Could you try putting a focus chart on the wall and panning it to either side and the middle of frame? This is a good way to compare sharpness of the different parts of the image.

April 9th, 2008, 06:40 AM	#19
Steven Thomas Trustee Join Date: Sep 2005 Location: Gilbert, AZ Posts: 1,896	No offense taken,but, You need to pull up: http://www.aerialsfilm.com/stevet/Im...ull%20tele.jpg It's a 1920x1080 image, so open the image full frame. Look at the guy fishing and compare to the guy with the girl on the right. Look down at the rocks and grass. They are at the same focal plane across the frame. There's a dramatic difference here and is real obvious on a 24" monitor. In fact, this is the first shot we looked at after running some RED tests. We both went... what the heck is that... If you can not see a difference between the middle of the screen and right side, maybe there's something wrong with your monitor? Also, like I've been mentioning in this thread, the problem is when the EX1 is at or near full tele AND focusing on distant objects (over 25 feet). I plan on setting up a rez test, but I know the issue is shown at far focus. I may set the chart up at as far a distance as I can and still be able to frame it. BTW, I do not use detail ON, therefore, the overall shots may appear a bit soft. I'm not sure the about the turn on point for this issue, but it was not there in previous work. We do event work and we rely on a lot of tele shots. I've only had this camera since the end of January.

April 9th, 2008, 08:08 AM	#22
Daniel Epstein Trustee Join Date: Jan 2006 Location: New York, NY Posts: 1,267	If you are shooting with wide open Iris at Full Telephoto you are going to see all sorts of focus issues with many lenses. Try doing the same shots with and without the ND at different F Stops and see if the problem is triggered at a particular setting. Many lenses get very soft at the Telephoto end.

April 9th, 2008, 08:10 AM	#23
Steven Thomas Trustee Join Date: Sep 2005 Location: Gilbert, AZ Posts: 1,896	I can't disagree at all regarding IR, but there's a distict difference with focal plane from center to edge. This particular shot was white balance set about 6300. It's was on the warm side. I set it to this setting to match the RED ONE setting. The RED also has the IR issue, but his same shot is far better for focus deviation across the image. I can find out what he was using for a lens, but it was not anything special. Regardless, I'm seeing the right side of the image fall off for focus. It's happening in ALL my shot on the tele end focusing at 25 feet or more. It was not there before, I have 40 foot zoom shots that look great edge to edge taken outside in sunny AZ. I will be performing rez chart tests at different focal distances. Unfortunately, the EX1 I would be able to compare will be in Portland OR for a month.

April 9th, 2008, 08:32 AM	#25
Steven Thomas Trustee Join Date: Sep 2005 Location: Gilbert, AZ Posts: 1,896	I know Dan, the far bank shot was probably close to f4. I'll try more tests, but yesterday I saw the same thing at f4 at 30 feet. Also, when I'm shooting f1.9, full zoom tele and focus at 20 feet or less, it looks great.

April 9th, 2008, 09:12 AM	#26
Paul Curtis Major Player Join Date: Mar 2005 Location: canterbury Posts: 411	Doesnt the EX have CAC (chromatic aberration correction) built in. Is there a chance that this isn't working in these cases. I remember ages ago on this forum a test movie that showed that if you're zooming then the CAC doesn't kick in until you stop and you can see a definate sharpening of the image when it does. So with these tests have you tried slowly zooming then stopping and looking at the zoom portion and the static portion and see if the issues are the same in both. If they are then it could be that somehow the CAC is off. It does look like both sides are soft but not just that but it looks more like CA than general softness, although that's difficult to judge. just a thought.. paul

April 9th, 2008, 10:40 AM	#27
Steven Thomas Trustee Join Date: Sep 2005 Location: Gilbert, AZ Posts: 1,896	Paul, that's not a bad idea about checking slow zoom movement compared to the static image. Having said that, I never really looked at the difference of CA zooming verses not, so I'm not sure if I have a reference to determine if CAC is working or not. Yes, both sides are soft, but the right side shows more CA and is more out of focus. After we spotted this issue and compare the RED frame against the EX1, I called up my wife who's not a camera tech. We asked her what she thought might be wrong with the fishing image. She said the right side looked burry. It's true the left is soft too, but I'm not sure if that may not be normal for that particular zoom shot. I'll know a lot more when I get a chance to do the rez tests at different distances.

April 9th, 2008, 11:13 AM	#28
Paul Curtis Major Player Join Date: Mar 2005 Location: canterbury Posts: 411	Im looking through a load of footage now. i have some stuff at full telephoto but probably not at infinity. I don't see anything like this on any footage shot over the past 4 weeks (and we have around 3 hours of drama shot all over the place INT and EXT). I will try and wave the camera outside and take a look later or tomorrow. I've been shooting with no detail and as little enhancing on as possible, whether that makes a difference im not sure. Have you been doing the back focus adjustment? I wonder if there's a chance that can screw up the CAC. Or whether something is set incorrectly when moving between full MF and Auto. I've definately had a couple of moments where something hasn't engaged quite right. Have you tried adjusting the images in photoshop - scaling the channels differently to see if that clears up the aberrations? At least it would indicate that it is a lens aberration problem, not focus strictly speaking. cheers paul

April 9th, 2008, 12:04 PM	#29
Steven Thomas Trustee Join Date: Sep 2005 Location: Gilbert, AZ Posts: 1,896	I'm going to test more on Friday morning. All of my tests have confirmed that it's worse than it was two weeks ago, that's for sure. Sony had me perform a camera reset (for giggles) and test it again. They want me to send it in. My back focus is a tad softm(not that bad). I have never performed the BF adjustment myself on the EX1. They want to upgrade to software 1.05 and go through all the camera checks. I plan on shooting rez charts at different distances and apetures and will include these images when I return it.