I just completed a shoot for a client and discovered the center of the image is sharp but it's soft and basically out of focus everywhere else. Anyone got any ideas?

Just bought the camera from LensRentals and it only had 310 hours on it.

https://f.io/St9zRFEv

I went from 2.8 to 8 and it made no difference. It is more noticeable on the right side of the frame but it's definitely noticeable on the left as well. Center is the only place that is sharp.

Any advice would be appreciated.

Thanks,

David

David, I can tell from the clip's metadata that you have the Macro switch turned on. Try another test with it turned off. I'm not sure if it will make a difference or not but you need try that before sending it in for repair or for a refund.

Doug - thanks,

That didn't do the trick. I can tell you there is a humming/buzzing coming from the lens area that almost sounds like a short circuit. If I move the ring back to the manual focus position the noise stops. This is when the camera is fixed in place and focused on a fixed object so it's not as if it is tracking and moving around.

I'll be calling lensrentals Monday and seeing what they have to say. They sold me this as an excellent condition camera.

Thanks again,

David

Also, make sure you are not shooting much past F/5.6 to avoid diffraction which becomes more apparent as you resolve further from the center of the lens. The Z280 seems to prefer F/4.0 or wider to get the best out of its lens. I think Doug with his experience with the Z280 may attest to this as well.

The Z280 1/2" sensor is 6.4mm x 4.8mm. This means a diameter of = 8mm. On that basis, you have a 4096-pixel width sensor with photosites (pixels) of 1.56µm width.

As you can see from the accompanying images a sensor with the above specs or close to them will start to exhibit diffraction at F/5.6 and beyond. For a 4K 2/3" sensor you start to run into diffraction at around at just under F/8.0. For sports OB shoots 1st-grade stadiums have specifically mandated very even lighting requirements for TV coverage, The minimum lighting for those stadiums is set at a level where modern 2/3" cameras can shoot at F/8.0. Setting F/8.0 avoids diffraction and helps the close-up cameras work with as much DOF as possible for the fast-moving action. The CCU operator will set the cameras at F/8.0 and no more adjustments are made to the apertures unless a director calls a camera off the pitch lighting into a crowd shot or similar where the lighting is of a lower level.

I find with the 1/2" cams, especially the 4K ones if you can stay at F/5.6 or wider then generally you will get the best results. The Z280 if stopped down below F/8.0 can go quite soft. Especially in 4K at the longer end of the lens. But then this type of diffraction performance applies to any 1/2" chip camera. Like Sony's earlier version EX and PMW series 1/2" cameras.

Sensor calculations based on sensor dimensions in millimetres

https://www.vision-doctor.com/en/camera-calculations/sensor-diagonal-sensor-ratio.html


Diffraction limits

https://www.cambridgeincolour.com/tutorials/diffraction-photography.htm

Chris Young

Thanks for the info. Per Dougs advice my main shoot was at 2.8. The video link above was between 1.9 and 8 just to see if there was any difference (there was none).

There is something definitely wrong with the camera/lens. It should not be soft at all on the outside ends of the frame with people on the same plane.

https://f.io/AD-UVksJ

If you look in that photo the person sitting to the right is completely out of focus and even the person in the center is sharp in only parts of the shot. I couldn't get a 2 up shot of people because of this.

I'm hoping Lensrentals will do the right thing and take care of this. I bought this less than 30 days ago and have only used it on 2 shoots. The other shoot was of a single person and there was enough distance between them and the background that I didn't really pay attention to the outer sides of the frame figuring it was DOF causing the background to look OOF.

https://f.io/N2lmLodJ - You can see I purchased the one with "exceptional glass".

Thanks!

David


Also, make sure you are not shooting much past F/5.6 to avoid diffraction which becomes more apparent as you resolve further from the center of the lens. The Z280 seems to prefer F/4.0 or wider to get the best out of its lens. I think Doug with his experience with the Z280 may attest to this as well.

The Z280 1/2" sensor is 6.4mm x 4.8mm. This means a diameter of = 8mm. On that basis, you have a 4096-pixel width sensor with photosites (pixels) of 1.56µm width.

As you can see from the accompanying images a sensor with the above specs or close to them will start to exhibit diffraction at F/5.6 and beyond. For a 4K 2/3" sensor you start to run into diffraction at around at just under F/8.0. For sports OB shoots 1st-grade stadiums have specifically mandated very even lighting requirements for TV coverage, The minimum lighting for those stadiums is set at a level where modern 2/3" cameras can shoot at F/8.0. Setting F/8.0 avoids diffraction and helps the close-up cameras work with as much DOF as possible for the fast-moving action. The CCU operator will set the cameras at F/8.0 and no more adjustments are made to the apertures unless a director calls a camera off the pitch lighting into a crowd shot or similar where the lighting is of a lower level.

I find with the 1/2" cams, especially the 4K ones if you can stay at F/5.6 or wider then generally you will get the best results. The Z280 if stopped down below F/8.0 can go quite soft. Especially in 4K at the longer end of the lens. But then this type of diffraction performance applies to any 1/2" chip camera. Like Sony's earlier version EX and PMW series 1/2" cameras.

Sensor calculations based on sensor dimensions in millimetres

https://www.vision-doctor.com/en/camera-calculations/sensor-diagonal-sensor-ratio.html


Diffraction limits

https://www.cambridgeincolour.com/tutorials/diffraction-photography.htm

Chris Young

Just to add - here is an audio file of me with the camera on and moving between manual and auto focus and I'm not changing the zoom at all and it's a fixed subject. The focus is not moving but you can clearly hear some type of motor humming/buzzing sound.

https://f.io/tntobq0A

Thanks again!

David

Doug - thanks, That didn't do the trick. I

Yeah, I didn't think it would fix the problem, but worth checking nonetheless. Hopefully LenRentals will stand behind it. I do know that LenRentals and Sony have some kind of official relationship because every time I get demo gear from Sony it come via LensRentals.

Also, make sure you are not shooting much past F/5.6 to avoid diffraction which becomes more apparent as you resolve further from the center of the lens. The Z280 seems to prefer F/4.0 or wider to get the best out of its lens. I think Doug with his experience with the Z280 may attest to this as well.

Yes, that is all true. I shoot 99% of everything with my Z280 at f/2.8, which is really easy to do thanks to the variable ND filter. About the only time I'll go smaller than that is in really strong brightlight and I've maxed out the internal ND and I don't have a ND filter handy to put on the lens.

I wish it was possible to map the iris ring on the lens to change the ND filter instead of the apergure. That way I could lock the lens at f/2.8 but still make my on-the-fly exposure changes with the iris ring. That would be a damn cool feature to put on a camera.

Here's a video I produced a few years ago to address diffraction and back-focus on the Z280.
https://youtu.be/U_JSeBvpkKo

If you look in that photo the person sitting to the right is completely out of focus and even the person in the center is sharp in only parts of the shot. I couldn't get a 2 up shot of people because of this.

Yes, this is beginning to sound more like a centring/tilt issue with one or more of the lens elements. Time for it to be replaced. With camcorders, it's best to replace the whole lens assembly as a single unit not 'fix it'. I know a really good Sony factory-trained tech who says ever since the advent of the EX1 camcorders this is the only real way to fix lens-related issues with the one-piece camcorders. Good luck with Lensrentals. Roger Cicala has a good reputation so I think you should be fine.

Chris Young

Good to hear from you and Doug that Lensrentals is a stand up company. I'm hoping that will prove true tomorrow when I call them. I'm newer to the higher end of the videography market but have been in photography for 30 years. I've done all sorts of lens tests over the years and I understand what should and shouldn't look right.

I don't think I'm making a huge issue of something small, it's a huge issue and needs to be rectified. I can't deliver footage like that to my clients.

Thanks for all the input and encouragement.

Best,

David

Yes, this is beginning to sound more like a centring/tilt issue with one or more of the lens elements. Time for it to be replaced. With camcorders, it's best to replace the whole lens assembly as a single unit not 'fix it'. I know a really good Sony factory-trained tech who says ever since the advent of the EX1 camcorders this is the only real way to fix lens-related issues with the one-piece camcorders. Good luck with Lensrentals. Roger Cicala has a good reputation so I think you should be fine.

Chris Young

Well this is the best proof I have. About 30' from the subject - just a sign. It's obvious the picture is not sharp around the edges and I'm even beginning to question the center sharpness (It's not as tack sharp as I'd expect).

This was shot wide open.

https://f.io/EaoLlMu9

Wish me luck on my call with Lensrentals tomorrow!

David

Yes, not good at all. That is really beginning to look like out of focus on the near side on one edge and out of focus on the far side on the other edge. A sign that one or more elements are not sitting parallel to the film/sensor plane. Trust you get it sorted out soon.

Chris Young

Submitted videos and photos to Lensrentals yesterday. They had to escalate it to upper management since I'm outside the 14 day window. The camera shows zero signs of ever being dropped or any physical damage so I'm curious as to how that happened.

I treat it with kid gloves and it's either on a tripod or in a pelican. I'll update as I find out more.

David

In a span of few years I had two camcorders with lens/focus issues. Both I believe were open box specials with low or no hours. They don't need to be dropped to have an issue the manufacture had to replaced the lens. I'd imagine the manufacture would need to examine it and do the same.

I’m curious how LensRental described the Z280’s condition when they offered it for sale? Do they test the cameras/lenses prior to putting them up for sale?

https://f.io/N2lmLodJ

That's how they described the camera.

Thanks!

I’m curious how LensRental described the Z280’s condition when they offered it for sale? Do they test the cameras/lenses prior to putting them up for sale?

Thanks for the info. Followup post is below.

Best,

David

In a span of few years I had two camcorders with lens/focus issues. Both I believe were open box specials with low or no hours. They don't need to be dropped to have an issue the manufacture had to replaced the lens. I'd imagine the manufacture would need to examine it and do the same.

Update:

Camera has been returned to Lensrentals. They told me it comes with a 90 day warranty and when speaking with their techs (they can repair onsite) they said they will take care of me either by fixing, refunding or replacing the camera.

They should get it Thursday June 16 and I hope to have an update by Friday.

So far, they seem to be understanding and cooperative. I hope that holds true. I've dealt with them in the past (only for rentals) and they have been great!

Best,

David

Update:

Camera has been returned to Lensrentals. They told me it comes with a 90 day warranty and when speaking with their techs (they can repair onsite) they said they will take care of me either by fixing, refunding or replacing the camera.

They should get it Thursday June 16 and I hope to have an update by Friday.

So far, they seem to be understanding and cooperative. I hope that holds true. I've dealt with them in the past (only for rentals) and they have been great!

Best,

David
Buying used, you save money and it often works out, but sometimes it doesn't that's part of the trade off. It's good that you caught it before the 90 days.

I'd never buy used gear from a rental house because you don't know how badly customers have beaten it. Much better to buy gently used gear from an experienced owner/operator who takes care of his/her stuff.

Good point. I've never bought from a rental house. Even on ebay it's best to buy from the original owner when possible because any reseller doesn't know the history or how it was treated. But I've had to return even from individuals who were trying to unload gear that has issues without disclosing it.

Well if you have a line on any Z280's as you describe please let me know! Right now they are hard to come by. Lensrentals told me they will fix it and make it right or refund me. Fingers crossed.

Best,

David



I'd never buy used gear from a rental house because you don't know how badly customers have beaten it. Much better to buy gently used gear from an experienced owner/operator who takes care of his/her stuff.

From LensRentals:

Hi David,

I wanted to let you know that our tech has inspected the camera and has found that the optics are misaligned. He is sending it to our in-house repair department for further testing and inspection. I will reach out with an update once that is complete. Please let me know if you need anything in the meantime.

Thank you and have a wonderful weekend!

Kim
Lensrentals.com

Update:

Camera was shipped back to Sony and the lens was replaced. It is perfect!

Major props to Lensrentals for backing up their gear and they also provided me a loaner while mine was gone.

David

Happy outcome. That's really good to hear.

Chris Young

It seems like my EX1 is similarly fated. Wide-open it goes soft on the left side of the image. Looking back through some older footage, it seems that it has been happening for a while in low light situations but I did not spot it.

@Doug Jensen,

Can you tell me what utility you use to view metadata? Anyone else?

Thanks!

David

David, I can tell from the clip's metadata that you have the Macro switch turned on. Try another test with it turned off. I'm not sure if it will make a difference or not but you need try that before sending it in for repair or for a refund.

Sure, I use Sony's Catalyst Browse software. Not only is it free, none of the other camera manufacturers having anything like it.

Thanks @Doug Jensen! The software is amazing! I just purchased a 2nd Z280 and now I'm in the market for a PTZ camera for my production company. Looking at the Sony BRC-X1000 but also looking at the Panasonic UE150 as well. I'll see if anything new pops up at NAB.

Thanks!

David

Sure, I use Sony's Catalyst Browse software. Not only is it free, none of the other camera manufacturers having anything like it.