AC160 Possible focus fault, soft picture.

B

Bo Sundvall

Active member
Hi
I think I have a problem.
About two weeks ago I bought a used AG-AC160AEJ, used only 23 hours. I have used camcorders for about 15 years filming
family, nature and also some payed gigs. I consider myself a serious hobbyist. I own a Canon HV20, a Canon XH-A1, a
Panasonic TM900 and now a AC160.

The AC160 is really a great camcorder. Fantastic in low light compared to my other cameras, great lattitude, good lens
with enough wide and tele, all controls where one could expect them to be. For the most parts I'm very pleased with it.

But, there are two problems.

The picture is not sharp and it's noisy. I've tried all kinds of configurations but I can't get a really sharp picture
from it. I've tried to shoot clips with all kinds of settings, with aperture between full open to about F4.0, I've tried
to focus on distant and close objects, I've tried different values for Detail and V Detail, different Coring, different
Gamma settings, changed Matrix but the picture won't get really sharp. During test I don't use gain, and ND filters is
used to keep the aperture at F1,6-F4.0. Adding more detail in the setup gives a sharper picture but also adds more noise.

It's hard to describe the picture, but it's like diffraction, it softens the picture. It's subtle and hard to see on a 42"
HD TV, but on my computer monitor I can clearly see the difference between my TM900 and the AC160. The picture from the
TM900 is rasor sharp and more or less free from noise compared to the AC160. Compared to my XH-A1 the picture is sharper
and less noisy though.

I attach a picture, the AC160 to the left, the TM900 to the right. Focus is on the flowers on the table.
For the AC160 all settings are default Scene File 0, (that is 0 for all parameters), F1.7, ND 1/16, 1/60s.
I can see that compression during transfer isn't good for the quality, but I think the difference is visible.

I don't think that the person who sold the camcorder to me knew that there is a possible fault on the camera. As I wrote
earlier, the difference is subtle and must be checked on a computer monitor, on a TV it's very hard to tell the
difference, and absolutely impossible to see if there isn't anything to compare with.

The firmware version is 2.05, the latest downloadable from Panasonic is 3.05, don't know if an upgrade is a solution to the problem.

Do I have too high expectations about the picture quality of the AC160 or is there something wrong with it? Perhaps some
kind of adjustment has to be done to the focus/lens system? I find it strange that the TM900 gives a much sharper picture
than a 5x more expensive camera. Reading reviews on the web indicates that it can produce really good quality, full HD,
low noise picture, so I find my experience of the picture quality very strange.

I don't think that the soft picture is a user error as I'm aware of how wrong settings can give bad results. I've also tried so
many settings but never got a picture that is as good or better than the TM900.

The camcorder is under the three year warranty program so I think there will be no problem to get a check of it, but I
think someone here on this forum can give me some input first. I'm here very often to get info and also give info
sometimes so I know there is a lot of knowledge here.

Regards,
/Bo
 

Attachments

  • AC160_TM900.jpg
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To my eye, the 160 is out of focus. I assume you have the focus detail lines engaged? Keep in mind the 130 and 160 cameras have auto focus issues with contrast. Use manual focus as much as possible. Also, scene 1 is a default. Try scene 3.

Lastly, you may have a defective camera that is not registered properly relating to lens to target area.

My camera is sharp as nails.
 
I set focus manually on the flowers on the table. Hardly ever use autofocus. I have also tried different scene files but with no success. I will contacat Panasonic and claim a warranty check/repair.

/Bo
 
Bo Sundvall said:
I set focus manually on the flowers on the table. Hardly ever use autofocus. I have also tried different scene files but with no success. I will contacat Panasonic and claim a warranty check/repair.

/Bo
Click to expand...
Bo, expanding these shots greatly I see that these shots cannot really be compared as they are quite dissimilar. There is a huge amount of edge accutance on the right hand picture. This electronic sharpening will give the appearance of a sharper shot but when enlarged is quite ugly. Also the contrast range appears compressed on the right hand shot. This would also give the appearance of extra sharpness. I would repeat the exercise with better synchronised exposures and do a bit of pixel peeping on a large monitor to check objective sharpness. The 160 is capable of very subtle and extended gradation. Worth another look anyway before scooting it back.

PS: I looked at these at 500% magnification and it is clear that the right hand shot is under exposed compared to the 160 and seemingly much lower resolution. Look at the jaggies down the rear chair back when compared to the 160..
Cheers!
Rod
 
Last edited:
Hi Rod
Thanks for the answer.
I also have suspected some kind of electronic sharpening on the TM900. After all it's a consumer camcorder.
But I don't think that's the problem here.

The example I attached is perhaps not the best. I've done other tests and the TM900 have more details in the picture at full wide, compared to the AC160.
I have the experience that details can't be added with electronic sharpening, just edge enhancement.

I've done some tests outside filming flowers. If I zoom in fully on objects, the camcoder is razor sharp. Compairing fully in zoomed pictures from the both cams,
the AC160 is better than the TM900. Sharper, more details, more natural colours and better lattitude.

Another strange thing is that if I zoom in full on an object and adjust focus and then zoom out to full wide, the picture goes out of focus.
I allways keep the aperture between f1.6 and f4.0. The phenomenon can best be described as diffraction, as the picture seems blurry and out of focus,
but as I keep the apertures at those values, the diffraction should not be visible.
I've had diffraction in the past on other cams so I know what it looks like, and also how to avoid it.

I've already called Panasonic service and they will pick up the camcorder tomorrow. It will be interresting to see hat they find.

Regards,
/Bo
 
kwkeirstead said:
Hi Rod.. Excellent detective work.

I can see I will shortly have to break down and order the 7in Marshall monitor that you ordered.

I had the misfortune to see a post by HDWarrior on quadcopters - the only way I have been able to sleep at night is by reading my blog posts.

http://www.hdwarrior.co.uk/2014/04/23/the-best-piece-of-drone-video-i-have-seen-in-a-long-time/
Click to expand...
Ha! yes me too I'm afraid. I am desperately trying to create a market that would morally justify me investing in such equipment. Especially with a gymbal fitted. ( stedicam pilot user- must have stability!!)
Cheers!
Rod
 
Bo,
"if I zoom in full on an object and adjust focus and then zoom out to full wide, the picture goes out of focus."

This is indicative of a back focus problem. The service center will likely perform a "software alignment" that will (hopefully) fix the issue and bring the camera up to spec. Unless there is a physical fault with lens elements or tracking mechanics (ie: a bad lens assembly). Fortunately, you're still under warranty.
Ken
 
I have also thought of that, there might be a back focus problem.

Just remebered another strange thing. If I zoom in on an object a LONG way from me, say 300-400 meters, and adjusts focus using fucus assist in red, the indicatotor says 28 meters. Going up to the infinity marker directly gives a picture out of focus. Even to get objects kilometers away in focus, I can't go up to infinity marker, 28-30 meters is max, over that, picture goes out of focus.


Regards,

/Bo
 
I've noticed a similar problem with my camera and need to send it in. I zoom in all the way to focus and then pullback. On the last 10% of the lens range, I can see the focus noticeably shift.
 
Hi

Exactly the same behavior as mine. Somwhere beteende full tele and full wide the picture gets out of focus. Probably around the same zoom value as your camcorder. I can't test it as it's sent to service now.


/Regards,

/Bo
 
Hi

The camcorder is back from service.

First of all I must say I'm very impressed with Panasonics warranty service. I made a service request on the 29:th of April.
Because of holliday here in sweden the camcorder wasn't picked up until 2:nd of May. Panasonic also delivered a padded
box to send the camcorder in, as I didn't have a box myself. The box should have been delivered the day before the pickup
of the camcorder, but because of the holliday it was delivered at the same time as the pickup. No problem to do a fast packing of
the camcorder, put the adress note on and the camcorder went away. 14,5 hours later, the camcorder was in Bristol,
about 2500km from my home. Because of a holliday in England the 5:th of May, the camcorder arrived to the service center
the 6:th, got service and was sent back to me the 7:th, and arrived to me the 8:th at about 2p.m.
From pickup to delivery, 6 days (142 hours), including two days of weekend and one day of holliday.
Extremly impressive and 100% professional service.

About the camcorder. There was probably some kind of focus error on it. The protocol says that they have done
a back focus adjustment. I tested the camcorder yesterday and it's now much better. I also have a feeling that
the picture noise is less after the service, perhaps an effect of better focus. Yesterday when I tested it outside
there were clods and gray sky, so there was very bad contrasts for filming. It will be very interresting to see how
it will work when the weather gets better. I'll also going to try different settings to get the best picture out of it.
I still have a feeling that my TM900 is sharper, but that might depend on some electronc sharpening in the camcorder.
It's only visible on a computer monitor, not on a TV. The AC160 has a much sharper picture than my Canon XH-A1,
and that is visible on the TV, so all in all I'm very pleased with the AC160.

Sharpness isn't all, the AC160 is a much better camcorder, better lens, better latitude, much better in low light,
less picture noise, SD-cards, over/undercrank, better LCD etc. The list can be longer but these are the most positive
changes over the Canon XH-A1.

Regards,

/Bo
 
Hi

I've tested the camcorder a little more after it arrived back from service.
I'm still not 100% pleased with the sharpness at full wide.

Yesterday I filmed the moon. While adjusting the focus, the focus meter went over from meters to the infinity symbol,
and the moon was in focus.
The strange thing was that I could continue to turn the ring and the moon got out of focus.
It seems as when the focus reaches the infinity mark, the lens system can continue to move and get to 'over' infinity.

From my point of view, the moon is probably the most distance object we on this planet can focus on.
The camcorders focus should not be able to focus further away, but it seems as this is what happends with my camcorder.

Can anyone confirm that, with their camcorder, when the focus reaches the infinity mark,
that there is nothing as 'further away than infinity'. Or is my camcorder still in need for adjustments and
the above explanation of the behavior gives a wide picture out of focus?

Regards,

/Bo
 
I think every stills lens I've ever had has allowed focusing "past infinity". And the entire Panasonic lineup starting with at least the DVX100 has had the ability to focus "past infinity". On the DVX, infinity focus was achieved at MF95, but the lens could go to MF99. I imagine the extra range was there to compensate for excess heat or cold or such, which might cause the body of the camera to grow or shrink slightly, thus necessitating an ability to compensate.

Turn off the feet/meters readout and switch over to the numbers, and see if the moon's in focus at MF95. If it is, then your camera is acting exactly like every other Panasonic handheld for the last 11 years...
 
Hi

Barry, correct as always!

Infinity focus at MF95, the lens goes to MF99, just as you said.

Thanks for the fast answer!


Regards,

/Bo
 
I have the exact same issues with AC-160.....
Never experienced it before with the Sony lineup, so if has taken me a bit to get used to thats for sure.
All that aside I find it a far better cam than the similar offerings from the other manufactures.
On the odd occasion I throw it into auto focus it has demonstrated the "beyond infinity" bug as well.
The other far more annoying bug is the awful side shift in the picture the "OIS" can often produce :(
When using handheld tracking a subject & then bring the camera to a fairly steady position you can get a fast shift to the left or right as the OIS brings it all back to center.
Often this can render the shot useless as it looks like someone has bumped into you :(
I wish Panasonic would address this with a firmware update as they have done with similar problems for Lumix lenses...
I am sure a firmware update is all that it would take...I would be over the moon if they would.
Sick of editing otherwise great shots to remove the pesty problem.
I even spoke to a Panasonic tech & he was very aware of the problem....but could offer nothing to fix it :(
 
Yes I think that is an issue with OIS systems. After all the camera is assessing camera movement and making an adjustment based on the previous image position- it is actually a best guess in reality and it has no way of knowing that the stop was not intentional and so blends that last movement to where it assessed it was going.. technically probably an inaccurate summary, but that is the outcome anyway!

I do not use OIS at all as I am always tripod or slider mounted, but if you create a slow to stop pan, is the problem still there?
 
It is actually hard to anticipate the problem...it will just pick a time to do it...usually the worst time of course :(
For certain products I have always shot with this hand held style.
Both my HVX-202 & AC-160 exhibit the exact same issue with OIS on...
I have shot for years with similar Sony camera's using their "steadyshot" and never once saw the quick shift sideways thing.
I am guessing that it makes it way back to center much slower & is therefore virtually unnoticeable.
I am however not trying to bag out the Panasonic cams....as I love & use them pretty much exclusively now, and have done for about 5-6years. Right from GH3's up to HPX-502's.
I just really wish they could write up new firmware to stop it...I would be in bliss then...lol
Its really ugly when it happens & looks like someone had bumped the camera in a big way...especially if there is a bit of zoom at the time...
 
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