Sony has confirmed that the backfocus problem with ND filters engaged is real and supposedly they have a fix. My camera just went in so I have my fingers crossed.

Recent cameras should already be fixed. software v1.05 is supposedly the fix. Sony repair in San Jose by the way has been very nice about dealing with this.

here is how to check it:

How to check Back Focus ( check this on a large monitor):

1. To allow for distant infinity focus, it is best to setup the camera outdoors ( this is not neccessary for a video camera but is for film or still lenses)

2. With ND filters off, zoom in ALL the way and focus on a distant object over 25 feet away (if you are indoors try it at closer distances at least 10').
KEEP YOUR APERTURE WIDE OPEN @ f1.9 THIS IS CRITICAL.
Depending on the available light, you may need to increase your shutter speed to not over expose, or perhaps even engage extra Gain as you change filter wheels.

3. Once you've focused on your distant object, zoom out full wide.
The wideangle is what we are most concerned about. That's where it will go off and you won't see it while shooting.
The wide image should still remain in focus.

4. Repeat this test with each ND setting. The camera should remain in focus regardless of the ND setting.

5. At both telephoto and full wide while keeping the aperture @ f1.9, flip through no filter then with ND filters.
The camera should remain in focus regardless of the ND setting.

Hope I explained this right its late.

Lenny Levy

How can you tell if it is in focus when you zoom out because the image is so small???

I must have this problem as a whole four days shooting is down the drain - everything out of focus!!!!

This year's must have accessory for EX1 owners - starburst wallpaper :-)

You heard it here first!

Cheers, Nick

Are there any more guys out there having success with this setting? I've tried it for 5 times yesterday but no such luck.

It is a 1.03 version and one of the very earliest cameras. I've scanned a Siemens star and printed it out on an A3 paper. I've printed 30 of such prints to produce a very large area! However I still could not go more than 2.5 mtrs (8 feet) away without getting something else in the screen.

And the problem in my case is also present without the ND filter. Once I'm zoomed in the picture is nice and focused - once I zoom out the picture can be seen getting soft.

I'm really eager to know whether others are having success with this recipe - as the photos attached by Gerald are really amazing and impressive.

Brian,
I´m very disappointed to hear that it did not work for you!
Maybe you can retry from a little further away? The testcharts did not cover the entire frame at full wide during my tests as well - that should not be the problem.
Maybe I really was just lucky - others even had success with only one test chart, which did not work for me.
Its weird...
I will retest the loaner camera with FW1.03 once again and more closely today, before it will be picked up tomorrow by UPS.
All this talk about working with only one ND-filter made me a little insecure and so I want to do some more tests. Time to open the box once again!
I will report back soon.

Gerald, I was actually very surprised when I read your successful method because as far as I know, a back focus setting involves a mechanical change. Thus in my opinion, when one does a BF setting on ND2 I believe that one looses the BF setting of the ND off (although I might be wrong as I'm no optic technician). In fact after I've done all the steps that you had performed and seeing that it did not work for me after a number of times, I decided to do the BF setting only on the ND off setting (that is without perfoming a BF adjustment on ND1 and ND2 so as not to alter anything just in case my reasoning is correct). However on examining the footage I still saw the horrible softening of the image on going to the wide setting.

Having said this, it might be that I'm doing something wrong and I'm not suggesting that Gerald's method is wrong. It simply did not work for me.

I'm tempted to go to a professional printer to have a big blow up of a Siemens chart printed on a poster so as to have the whole frame covered from a distance of about 4 meters - I know this sounds a bit crazy - but this camera is getting me crazy in the first place. And I have a feeling that if I manage to sort out this BF issue, the issue of seeing the picture go soft when downconverting from HD to SD will be resolved - just my hunch!

I've scanned a Siemens star and printed it out on an A3 paper. I've printed 30 of such prints to produce a very large area! However I still could not go more than 2.5 mtrs (8 feet) away without getting something else in the screen.


I guess that it is not too important that the charts cover the field of view. What is important is that there is nothing within the field of view at a different distance that will be used by the camera to get its wide angle focus. I am assuming that there is no need for proper backfocus charts - the procedure might well work if you show the camera a big expanse of brick wall or other surface sufficiently textured for it to get a focus.

Nick

Gerald, I was actually very surprised when I read your successful method because as far as I know, a back focus setting involves a mechanical change. Thus in my opinion, when one does a BF setting on ND2 I believe that one looses the BF setting of the ND off (although I might be wrong as I'm no optic technician).

There is no mechanical adjustment. The EX1 lens is a servo controlled varifocal, which uses look-up tables to hold the focus as the lens is (mechanically) zoomed. This is cheaper than a lens optically designed to hold backfocus, and is the reason (along with electronic CAC) why the EX1 delivers the results it does at a price for the whole camera less than a 1/2 inch broadcast lens. The Auto FB process recalibrates the lookup table, which is why it is essential that the camera gets a focus at the same range at tele and wide. It seems that separate look up tables are used for each ND setting, which is why the calibration needs to be done for each ND setting.

Cheers, Nick

Just returned from the garden - loaded the testclips from the loaner camera (FW1.03) into Final Cut Pro and watched the clips in full resolution.
I did test shots switching between ND - filter positions multiple times.
The camera has FW 1.03 and I did the FB calibration with multiple charts on friday.
After very close inspection I can definitely say that it is perfectly fixed. The camera is tack sharp and spot on at all ND positions. Also objects really far away are sharp. (of course there are limits due to the lens glass...)
I can post another split screen image of todays testclips if you want.
Maybe you really need at least FW 1.03 to do the adjustment for all ND settings??? Does anybody know what Adam Wilt´s camera has?
So far all negative reports I read are coming from cameras with FW 1.02...

I will now put the loaner camera back into the box...

regards,
Gerald

Thank you Gerald - I followed your instructions using a display of 12 A4 Starburst charts )my local wallpaper shop had never heard of the wallpaper) - I placed this on a piece of large plywood about 4 foot by 6 foot and placed this against a wall.

I set the camera up about 10 foot from the charts.

The wide angle shot extended onto the ground and wider than the wall - the wall was about 18 feet wide. So the wide angle view extended well outside the wall.

The result was that the softness I have previously experienced has gone.

So thanks again - it worked for me.

Hi again,
after my dissapointing tests with the 12 focuscharts on my firmware version 1.02, I tried again.
This time I just took a huge house over the street which completly blocks the frame (about 10 metres away, relatively flat fassade) and ran fb auto with no focus charts at all.
This worked much better. But I´m very shure now that the camera remembers only the last auto allign run, at least in version 1.02.

So I took ND1 as a Medium setting and did the line up on this setting. That worked near to perfect for all settings , may be its perfect but I seem to be oversensibilized by now.

After very close inspection I can definitely say that it is perfectly fixed. The camera is tack sharp and spot on at all ND positions. Also objects really far away are sharp. (of course there are limits due to the lens glass...)
I can post another split screen image of todays testclips if you want.

Great to hear, Gerald! Makes me much more confident in buying.
Yes, please post split screen image.

Nick thanks for your interesting explanation. Following these recent posts I checked again my camera and realised that I had mistakenly thought to be a FW 1.03. In fact it is a FW 1.02 and it has never been sent back to Sony. It seems that Holger has almost solved his problem even though it is a 1.02 by going further away to do the test. I have yet to find such a scenario where I can do the test from about 10 meters away. Are there any more 1.02's who managed to solve the BF issue or do we need an upgrade to at least 1.03?

And more interestingly, are there any cameras which are being bought now that do not need any BF adjustments? If so, do they have the FW 1.05 or better?

Nick thanks for your interesting explanation. Following these recent posts I checked again my camera and realised that I had mistakenly thought to be a FW 1.03. In fact it is a FW 1.02 and it has never been sent back to Sony. It seems that Holger has almost solved his problem even though it is a 1.02 by going further away to do the test. I have yet to find such a scenario where I can do the test from about 10 meters away. Are there any more 1.02's who managed to solve the BF issue or do we need an upgrade to at least 1.03?

And more interestingly, are there any cameras which are being bought now that do not need any BF adjustments? If so, do they have the FW 1.05 or better?

Given recent posts on this subject, I need to choose my words carefully, but it seems that firmware version is not the problem. Folk's experience with the Auto FB procedure and the routine which we have developed between us, suggests that any firmware version will give an accurate backfocus if the procedure is done properly. The inescapable conclusion is that, for early cameras, Sony was not doing it properly. There seem to be two possible reasons:

1. The Auto FB procedure should have been run at the factory as part of the manufacturing process, but was forgotten, or

2. A standard set of focus look-up tables, which it was assumed would work for all lenses, was part of the firmware. The Auto FB procedure was only intended to be used at repair shops for cameras with backfocus problems.

I would assume the latter. It seems from the vignetting issue that Sony mistakenly thought that lenses could just be taken out of the Fujinon box, be fixed onto the camera and would work. Thinking that a default backfocus table would also work for all cameras is part of the same thought process.

Nick

What is "A standard set of focus look-up tables"?

It seems to me that the verdict is still not in on the backfocus issue but I am definitely not certain that my original post was correct that you need the 1.05 firmware. That's what Sony told me and I repeated it. I am inclined to expect that it should make some difference in how the camera back-focuses, but who knows at this point.

Pretty weird really.

I have heard some rumors from a Sony source that a new FW is in the works which should fix all problems.
I do not know how trustworthy this is - so please take it with a grain of salt.

It's possible that the camera's firmware was updated at the last minute which and for some reason, over wrote the BF lookup table. This could of happened when the cameras may have left the factory with version 1.01, but then was upgraded to a later version...

Of course, this is just a WILD guess.

Well, it appears at least versions 1.03 and up, if the procedure is done correctly, whatever that may be, it should work. Or, maybe Sony has a new firmware version to relieve this misery.

It's possible you want the target/s to fill a certain amount of field of view when wide, but not to much. All cameras, especially at full wide, have a slight difference in center to edge focus, curvature, or TFD (total focus deviation).

During the setup, when zoomed in, you filled the field of view with the target. (Wow, that was a tongue twister.. LOL).
You manually adjust focus on the siemens star.

At full wide, because the field of view is different for the target, the camera may find focus a bit different then where it would of if you were able to manually override the calibration when it went wide.
Hmm... That may be a great user option to have in a firmware upgrade and offer it in a regular menu location.

I have a feeling it's just dang senitive to the setup.

Adam Wilt just reported he was able to get his EX1 camera BF decent by using a large target and setting all three ND settings.
Great news!

We will eventually figure this out.
We are almost there, if not there already. What we really need is Sony to drop in and set us straight about this issue and what the firmware versions entail.
Maybe a new version???

What is "A standard set of focus look-up tables"?



Hi Leonard

I'm guessing that to control costs, Sony want cameras which are put together on an assembly line and come off the end (a) identical and (b) ready for end users without the need for any calibration. This is how Handycams (up to and including the Z1) are built, and it seems to work. All of the variables in the software control, such as exposure, translating zoom and focus inputs to the movement of glass, are the same from one camera to the next, partly because their Zeiss lenses (which are designed with help from but not built by Zeiss) have build consistency absolutely nailed.

It seems with the EX1 that they wanted to do the same. Unfortunately, a combination of very fine tolerances and some variation between Fujinon lenses (after all, their other products all get individually calibrated) meant that this approach did not work. My guess is that they built prototypes and calibrated them, then lifted all the calibration data including the lens control tables into the production firmware. As we are seeing, with a significant number of cameras this approach results in less than perfect operation.

Nick

I have heard some rumors from a Sony source that a new FW is in the works which should fix all problems.
I do not know how trustworthy this is - so please take it with a grain of salt.


Do you guys really think that a firmware update is going to fix the backfocus issue automatically without any adjustment?

Do you guys really think that a firmware update is going to fix the backfocus issue automatically without any adjustment?

No,
we can ONLY hope they PLEASE offer the upgrade via download and a USB flash at our own risk. I'm praying this is the case.

It's going to be way to much burden to have them deal with this issue. The vignetting is large enough.

Again, I'm hoping they offer us the procedure and USB software and add the disclaimer to try this at your own risk.

Do you guys really think that a firmware update is going to fix the backfocus issue automatically without any adjustment?

NO - I´m sure adjustment will be necessary.
From what this source said - there even might be a recall for some cameras (he is not sure about this) - even for the new FW it will be necessary to send the camera in to Sony.
I do not know how trustworthy this source is - he says he worked for Sony and still has some good contacts there. Its only speculation...

Again, I'm hoping they offer us the procedure and USB software and add the disclaimer to try this at your own risk.

Why should there be any risk? If it messes up the camera it should be Sonys problem since it's their firmware.

There is a risk, because it's possible to brick a camera during a firmware upgrade if the procedure isn't done properly. A botched upgrade procedure performed by the manufacturer's service center is their fault -- but if you do it yourself and botch it, then it's your fault. Thus the disclaimer as Steven Thomas rightfully suggests (and it's a standard warning from any manufacturer).

I

Adam Wilt just reported he was able to get his EX1 camera BF decent by using a large target and setting all three ND settings.
Great news!

Thats indeed great news!!!
Looks like my method really works! A large enough target and doing the calibration for each ND setting seems to be the way to fix it.
Adams technique to use a huge monitor displaying a Siemens star is an excellent idea!

Can someone please point me towards Adam's report. AS I posted elsewere Gerald's suggestion solved my backfocus problem.

End of page:
http://provideocoalition.com/index.php/awilt/story/ex1_misfocusing_explained/P1/

I have had no luck getting my backfocus fixed through the maintenance menu. It is certainly infuriating.

Do others who have BF problems notice that (at least with the ND on) the only way to get far away things in focus is to turn the focus to the minimum distance? I can zoom into some far away trees and get focus and pull out but have to go to the opposite end of infinity to get infinity focus. Aargh!

Benjamin

Benjamin,
I´m sorry to read that it did not work for you.
I had exactly the same situation with 2 cameras before I could fix it.
Did you try the adjustment as described in this thread?
Most of the users who tried it so far had some success.

I have tried it with one chart, six charts and just tried with a siemens chart displayed through a 50" plasma (although that got really weird looking and probably was not as good an idea).
I called the highly reputable dealer in Boston that I bought it from and spoke to their head engineer and was surprised that to his knowledge nobody else has mentioned the backfocus problem. They have sold a lot of EX-1s and rent them as well. It had me thinking I was just being crazy and seeing a problem that was not real but I have confirmed that it is a problem. The dealer will certainly support in getting it to Sony, but I am just scared from people saying Sony did nothing to fix it.

Benjamin what is your camera's firmware version? I too have not been successful after more than 10 attempts and making sure I'm following Gerald's procedure to the letter. My FW is 1.02

Gerald, could you post another split screen image of your actual testclips?
Would be very much appreciated. Thanks in advance.

Benjamin what is your camera's firmware version? I too have not been successful after more than 10 attempts and making sure I'm following Gerald's procedure to the letter. My FW is 1.02

FW 1.03. Gonna try again today.

Gerald, could you post another split screen image of your actual testclips?

These are my before/after tests - roll mouse over image to switch:

http://www.mdma.tv/ex1/fb.html

Full story here:

http://www.dvinfo.net/conf/showthread.php?t=108433&page=47

Perhaps this thread is a more logical place to continue.

Much appreciated, Matt, thanks.

Gerald, could you post another split screen image of your actual testclips?
Would be very much appreciated. Thanks in advance.

Michael,
unfortunately I already formated the SxS card with the test clips of the loaner camera, as it was picked up today - they looked exactly like the ones I already posted on this forum from my camera - no difference at all. (looked exactly like this: http://www.dvinfo.net/conf/showpost.php?p=850529&postcount=3 )
Sorry,
Gerald

These are my before/after tests - roll mouse over image to switch:

http://www.mdma.tv/ex1/fb.html

Full story here:

http://www.dvinfo.net/conf/showthread.php?t=108433&page=47

Perhaps this thread is a more logical place to continue.

Has Sony (or the service manual) said the FB adjustment needs be done once for each ND setting or is this a sumize?

I talked with Sony today on the BF problem and was told NO you do not need to do it with ND on that is only remembers the last adjustment. Also I was told that it is better to have a black background and only the Focus Chart/black background in the frame at full wide. But it seem that Gerald has proven that this is not needed.

Then I said that will not be easy for me at full wide and 3 meters how about a brick building. He said that was fine but make sure it is well lit and be wide open iris.

I talked with Sony today on the BF problem and was told NO you do not need to do it with ND on that is only remembers the last adjustment. Also I was told that it is better to have a black background and only the Focus Chart/black background in the frame at full wide. But it seem that Gerald has proven that this is not needed.

Then I said that will not be easy for me at full wide and 3 meters how about a brick building. He said that was fine but make sure it is well lit and be wide open iris.

The fact that many NEED to find that setup to properly tune our BF is ridiculous. I tried again today (6 charts on white wall) with fellow DVinfo user Bill Parker (who also had bad BF problems). I got it all fixed (so I thought). Every setting looked sharp. We went to lunch and I was all happy. We came back and lo and behold my backfocus was off again.

It is right on with the ND OFF, but with ND I need to go to min focus to get infinity focused. Really stupid. I am giving up for now, as I have to travel with the camera this week but it is going to the dealer next week.

Aargh.

Benjamin that does not sound good.

Every setting looked sharp. We went to lunch and I was all happy. We came back and lo and behold my backfocus was off again.



Hmm...
Why is this?
It was good, then bad. Strange.

After you ran the calibration and determined that it was good, did you power cycle the camera, or did you keep using it for a while?

It sounds like there may be step needed to have it remember the settings.

I did the BF adjustment and then powered down and went to lunch. Yeah, is there a "Save" thing? I doubt it. This is troubling. Between this and my faulty zoom lever (doesn't do a slow zoom) hopefully Sony will deal with it.

Boo :-(

Well did Gerald's routine and back focus is still wrong. Actually after the two EX1s came back from service (first time) the zoom out (wide angle) setting didn't look as bad as it was before service.
Now for the bad news: Whole image be it zoomed in all the way or at widest focal length looks soft. i can't even have a pinch sharp image at telephoto. Another thing is that I can see cyan and red coloration at the edge of some of my subjects. Is that color aberration?
Got a call from SONY and they asked me to send both cameras back for the second time.
Generally it seems that backfocus is not the major issue but achieving a sharp focus in general.

Im am going to buy an EX1 during a vacation in the US and will not have access to an external monitor, hence my question:
Is it possible to judge proper or incorrect backfocus merely on the EX1' LCD, when magnification is switched to 1:1? I will carry a focus chart with me. Thanks in advance.

Michael,
you can see the backfocus problem on the LCD if you use the expanded focus.
Make sure to turn the focus to the 0,8m stop once you zoomed out, to make sure if there is any difference. Try it with objects that are far away.

regards,
Gerald

So far, I've not witnessed the typical backfocus problem symptomps with my EX1 - i.e. regardless of the ND filter settings, when I zoom in - focussed - zoomed out to reframe, the focus still held OK.

However, sometimes I'm in doubt when after engaging ND filter with auto iris on, I'm loosing focus. I thought (and would like to still think) this is due to the change in iris opening, which changed my DOF (and with 1/2" sensors it can be more noticeable than with my previous cameras like the V1 which only has 1/4" imagers).

To make absolutely sure, please tell me again what probably has been said many times already: when testing for backfocus problem, do I zoom in and focus for infinity before zooming out? Or does the fact that I'm loosing focus when engaging/disengaging ND with auto iris on also suggest my backfocus needs adjustment? Thanks!

Piotr,
It´s pretty easy to check.
Make sure that iris is set to manual and that ƒ1,9 is set. Adjust the brightness of the picture with the shutter speed.
Zoom in to an object thats very far away. Focus. Zoom out and see if your pictures is still sharp.
After you have zoomed out also turn the focus to the 0.8m stop and watch if the image gets sharper. If it does - your backfocus is off. If it gets blurry when turning the focus - its probably o.k.

When you checked your backfocus before - did you have the aperture wide open? Did it open further when you engaged auto iris?

When you checked your backfocus before - did you have the aperture wide open? Did it open further when you engaged auto iris?

Yep - that's the point. I never noticed striking softness when reframing, therefore I assumed my backfocus is OK. Only now, after I invested in a 50" HDTV as a preview device and watching some of my recordings again, do I notice that sometimes when engaging ND, my focus gets soft untill I compensated - but still, I think the autoiris was on and it simply opened up, thus decreasing DOF.

Nevertheless, I'm going to perform the proper checking procedure as you described, Gerald. Thanks!

I think hopefully a qualified camera tech will chime in here and maybe make some helpful comments.

It is possible with a PD150 to blow the image all out soft and furry if an overbright image is laid on the CCD and controlled only with shutter speed.

Unless the experiment is carefully controlled, it may be possible for a self-fulfilling "false" backfocus defect to be generated in the EX1 in the search for one, genuine backfocus faults in some cameras notwithstanding.

Gerald, can the LCD's expanded focus moved to the corners of the frame to control focus there as well?

Michael,
unfortunately this is not possible - its only a center zoom.

I think hopefully a qualified camera tech will chime in here and maybe make some helpful comments.

It is possible with a PD150 to blow the image all out soft and furry if an overbright image is laid on the CCD and controlled only with shutter speed.

Unless the experiment is carefully controlled, it may be possible for a self-fulfilling "false" backfocus defect to be generated in the EX1 in the search for one, genuine backfocus faults in some cameras notwithstanding.

Thats not the case here... It could be done, but then it would also be blurry if fully zoomed in. With ND2 on, the image itself is rarely too bright as well. I think what you mean is that one can also create a blurry image if the aperture is almost closed at ƒ16, as the EX1´s lens sweet spot actually is below ƒ8. If you close it further, the image starts getting blurry again and is completely fuzzy short before its closed completely. (but thats perfectly normal and differs from lens to lens)
I studied camera and work as a professional cameraman for 15 years now - so believe me, I know how to check backfocus ;-)