FS5: Anyone having parfocal issues with the Sony 18-110?

This begs the question. Did you get the slip of paper with the owners manual that stated "turn of correction."

Not everyone who bought this lens got that slip of paper in the box when they bought the lens. I didn't get one with the lens I got but I have seen this extra slip of paper in a freshly opened box at one of our Sony dealers stating turn the correction off. From what I have been able to deduce from talking to the supposedly knowledgeable people at Sony is that this "correction" in the FS7 at least and now it looks like the FS5 should be off. I know if you run the 18-110 on an a6500 with the camera lens correction menu off the optical distortion is horrific.

Fascinated now? It's night time here but I have just done a quick 4K indoor 'door frame' test wide through to full zoom with the lens 'correction' function both on AUTO and OFF and I cannot see any difference in distortion. If I get the chance tomorrow I'll try a chart and a brick wall to see if there is any difference with the correction menu on auto or off. I know with the 28-135 it had to be on and the downside of that was you could not shoot LOG without burning your VF 3D LUT into the internal record file. If we can run 4K LOG with the correction function off on the 18-110 as it seems we can then we can avoid the burnt in LUT issue. Worth investigating for sure.

Chris Young
 
Wow. This is like a whole new chapter in this saga haha. My lens absolutely did not have this paper. I’m going to run some tests now with correction off and see if it makes any difference with the focus slipping.
 
There's some confusion here between the 18-105 which is the lens that pincushions and needs correction from the camera, and the 18-110 which is a far better lens and does not need correction. It probably does take some power from the camera to stay par focal though I don't have any idea how that works.

Mine is par focal in UHD and HD - exactly the same . Hard to tell frankly at 18mm but it seems to stay oK down to 25. I'm sure my correction is always off.
 
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LennyLevy said:
Mine is par focal in UHD and HD - exactly the same . Hard to tell frankly at 18mm but it seems to stay oK down to 25. I'm sure my correction is always off.
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The plot thickens! Yes I know with the 18-105 if you run with correction off you have pin cushion distortion at one end and barrel distortion at the other. Your comment about correction off is telling me I have to get my finger out and do the tests... today!

Chris Young
 
I ran some unscientific tests today with correction off. Just getting focus on my son’s lashes and zooming out to different distances. Seems like it may be my lens or camera. Now on day 2 of waiting for a call back from Sony. I hate their support making you get a call back for these issues.
 
Ooh! Doesn't sound so good Newsguy. In the meantime any chance of trying the lens on another camera body, FS7 or 5?

Completed my tests with and without lens correction on in Cine EI 4k and with my naked eye I cannot see any difference. The 18-110 does suffer a bit of barrel distortion at the wide end regardless of whether the compensation function is on or off. Other than that nothing else observable. Being able to shoot with a monitor LUT of choice and record clean S-LOG internally is a definite plus for those shoots that require native S-LOG origination. As of late I've been shooting more S-LOG3 and burning in a LUT as I go now that I have a couple of my own LUTs that clients like.

Would still like to get any other users feedback on this correction AUTO/OFF question though... anyone?

EDIT: Just found a link to the insert slip for the 18-110 where it says: "To use this lens, select [Off] for [Distortion Comp.] on your camera."

https://docs.sony.com/release//Flyer_4695209011.pdf

Found here:

https://usermanual.wiki/Sony/SELP18110G.3329088142/html

Chris Young
 
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Well i'm going to throw a monkey wrench into this conversation . Although I've testified that I do believe my lens is parfocal, one thing about my tests has bothered me. That is when I focus at 110mm and then zoom out to wide the most IN focus Spot even on a 4x3 chart is hard to pinpoint as there is now more Depth of Field and thus what is IN Focus is now a range off distances not just a specific point is now a range . The wider the lens the wider the IN Focus area. Thus if at 110mm the sharpest focus point is at 10', at say 25mm I now see the sharpest focus to be aprox within the 10' to 25' range ( I'm not checking the exact distances on a lens at the moment) . So it seems par focal because at 10' its still as sharp as it , but the old rule of thumb is that DOF should fall roughly 1/3 in front of the point of best focus and 2/3 beyond it. ( aprox 7'-15'?) However that's not what I'm seeing on my lens.

That's a little unnerving to me. Nothing I can monitor shows any increase in sharpness past that 10' but maybe that's a limitation of the resolving power of my monitoring tools and actually;y it isn't par focal. . Because this Sony lens is achieving focus in an entirely new way I don't know if this is normal or not. A 4K monitor would help, or i guess I could try shooting a test and blowing it up in post.

A question for those you
 
Well i'm going to throw a monkey wrench into this conversation . Although I've testified that I do believe my lens is parfocal, one thing about my tests has bothered me. That is when I focus at 110mm and then zoom out to wide the most IN focus Spot even on a 4x3 chart is hard to pinpoint as there is now more Depth of Field and thus what is IN Focus is now a range off distances not just a specific point is now a range . The wider the lens the wider the IN Focus area. Thus if at 110mm the sharpest focus point is at 10', at say 25mm I now see the sharpest focus to be aprox within the 10' to 25' range ( I'm not checking the exact distances on a lens at the moment) . So it seems par focal because at 10' its still as sharp as it , but the old rule of thumb is that DOF should fall roughly 1/3 in front of the point of best focus and 2/3 beyond it. ( aprox 7'-15'?) However that's not what I'm seeing on my lens.

That's a little unnerving to me. Nothing I can monitor shows any increase in sharpness past that 10' but maybe that's a limitation of the resolving power of my monitoring tools and actually;y it isn't par focal. . Because this Sony lens is achieving focus in an entirely new way I don't know if this is normal or not. A 4K monitor would help, or i guess I could try shooting a test and blowing it up in post.

Newsguy ( or anyone else with par focal issue)s: Do you find the same pattern as i do : That as you go wider, the range of focus seems to move toward the infinity direction more than you would expect?

I am particularly interested in this question because a friend who rented my camera said he thought it was not parfocal, so I'm trying to test carefully as I can.
 
My specific issue is what you’re describing. From 10’ away I will zoom to 110, focus on eyelashes and zoom out. By the time I’m on a medium shot (waste up) of the subject, my focus has moved to their ears. From there, if I re focus, I can see that the lashes come back into focus, but when I zoom in, the lashes are no longer in focus.
 
Newsguy: Couple of questions:
1- What are you seeing this discrepancy on - VF? with peaking? VF with 4 or 8 times? Monitor ? what kind?

2 - Where is your focus at say 50mm 35 or 25? As you get wider does the focus get progressively even further off?

I will continue to check mine and will shoot a test that I can blow up in post to check focus more precisely since I don't see it get soft on the monitor , but I haven't checked eyelashes yet. There are 2 more around me that i can check also. Could be camera flange distance as well. I really doubt those tolerances are perfect. The F3 , and the I believe the F5/F55 all have adjustable back focus. But i have no idea how this weirdo lens works.
 
I have no way to check the different distances at this moment. I’m actually out of town on a shoot until March 6th, but i will be using the 18-110 for some stuff so I will let you know what I see when viewing in post. As for how I’m seeing the discrepancy, I’ve done it a few ways. The first is with a smallhd 501 with peaking set low (2 I believe). This way I get to the medium shot, focus magnify 2x on the 501 and I can see the softness on the lashes. I also record as I’m doing this, and then check in post. Also, I’ll take the raw video right from the camera and watch it on my 65” screen at home. This way it’s most obvious, as I can see when I zoom out the focus shift towards the ear. When I re focus from that distance I see the eyes sharpen again, and then when I zoom back in the original focus point is gone.

So because I am using this lens for handheld work on this job, I’ll treat it more like a photo lens and check my focus once I’ve zoomed out. This isn’t so bad, but in my particular case, I may have 2 shot interviews where I need to zoom in and out during the interview, and the beauty of a parfocal lens is that I am not shifting focus every time I zoom in our out. Sony never called me back either. What a pain.
 
now you made me feel very insecure and uncomfortable with this thread :D
On Friday I recorded a 1,5 hr stage discussion with the 18mm full stage view and 110mm medium CU. Focus was perfect in all angles. Whew.

oh, and by the way, XAVC-L did a pretty good job in 4K. I managed the presentation with a 128GB and a 64GB card and 4K allowed me to zoom from medium CU to sholder CU of the speaker.
 
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I have not had issues with my lens (knocks wood)... but reading thru this thread got me thinking of the first time I rented this lens to try it out & did see a few slight oddities when doing a "live zoom" from 110 to 18. Not sure it's exactly what Newguy describes... but it did make me hesitate before buying this "electronically parfocal" zoom (or however it actually works).

One other quick thought - Newsguy - how are you supporting the lens on your camera? Rail support? The rental I tried didn't have this - but the one I purchased came with this support attachment on the bottom of lens barrel - which helps make sure the notoriously flexible mount on my FS7 doesn't flex. Might that possible contribute to any issue?
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I support mine on with a rail support. I have the fs5 so I need it even more cause the lens is bigger than the camera lol.
 
I did a careful test with mine again today and it seemed spot on.
It is a little weird to me though because sometimes I've looked at it and it seems off though always in the opposite direction from Newsguy. But then when I test it carefully it passes. Beats the heck out of me but I got to go with the careful test. This time I recorded it in UHD and blew up the results in Catalyst Browse. Looked right on the money thank god. That was all at about 12'
 
Did any of you who had parfocal issues with your 18-110 send it off to get it fixed? I've noticed that mine is definitely not parfocal and want to see what to do from here to get that resolved.
 
To follow up with my last comment, I just got off the phone with Sony Pro Support who sent me a shipping label. I've worked with them before as a pro user and they are typically pretty good to work with. The guy I spoke with claimed that the 18-110's parfocal issue is not uncommon and that the engineers claim that all of the 18-110's should be parfocal electronically, so if you have one that's not you should definitely send it in so that they can make the necessary adjustments. They said they should have my lens fixed and cleaned and sent back to me in under a week. I am pretty excited about that.

If any of you are having issues with your 18-110 not being parfocal still, you should definitely send it off so that Sony can get that working for you. And if you're not a Pro member yet, I HIGHLY recommend it. They've been awesome about repairing things for me and getting my gear back to me almost immediately.
 
Joshua Milligan said:
To follow up with my last comment, I just got off the phone with Sony Pro Support who sent me a shipping label. I've worked with them before as a pro user and they are typically pretty good to work with. The guy I spoke with claimed that the 18-110's parfocal issue is not uncommon and that the engineers claim that all of the 18-110's should be parfocal electronically, so if you have one that's not you should definitely send it in so that they can make the necessary adjustments. They said they should have my lens fixed and cleaned and sent back to me in under a week. I am pretty excited about that.

If any of you are having issues with your 18-110 not being parfocal still, you should definitely send it off so that Sony can get that working for you. And if you're not a Pro member yet, I HIGHLY recommend it. They've been awesome about repairing things for me and getting my gear back to me almost immediately.
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I'm thankfully not having any issues with my 18-110... but am curious about Pro support.... do you sign up annually? And what is the cost / features? And if you don't mind answering - how much do they charge to fix the lens back to it's original working condition? Thanks.
 
As I pointed out in the third post in this thread it may well be the back focus needs adjusting on the camera mount. I've been told this by a very highly respected Sony Japan trained tech here in Sydney. Also due to the not very solid mount on the cameras when mounting on rails it is imperative to make sure there is absolutely NO upward, downward or sideways tension applied to the lens when the rail mount is tightened as this can cause the lens to range in and out of focus when zoomed. Up down out of alignment can evidence itself by the image being slightly softer on the top or bottom of the image and likewise left to right tension bias can be seen with left or right sides of the image being softer. On the Mk I FS7 the weight of the unsupported 18-100 can itself put a downward flex on the that original little still camera E-Mount. All very touchy.

Touch wood so far no parfocal issues with my now aging 18-110 which is standing up pretty well after a fair bit of long term use.

Chris Young
 
cyvideo said:
As I pointed out in the third post in this thread it may well be the back focus needs adjusting on the camera mount. I've been told this by a very highly respected Sony Japan trained tech here in Sydney. Also due to the not very solid mount on the cameras when mounting on rails it is imperative to make sure there is absolutely NO upward, downward or sideways tension applied to the lens when the rail mount is tightened as this can cause the lens to range in and out of focus when zoomed. Up down out of alignment can evidence itself by the image being slightly softer on the top or bottom of the image and likewise left to right tension bias can be seen with left or right sides of the image being softer. On the Mk I FS7 the weight of the unsupported 18-100 can itself put a downward flex on the that original little still camera E-Mount. All very touchy.
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Yeah the flex is no doubt a problem. When I had a FS7 MK I, the flex was so bad with the 18-110 that it wouldn't power zoom unless you lifted the lens slightly. Not good. I had to use rails and support it. With my FS7II I no longer have that problem. The mount is extremely solid, so to me it's no doubt a lens issue. Sony seemed to believe that as well.
 
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