FS700 With Macro Lens Issue
 

Hey guys

First time poster here and hope you can help.

I recently upgraded from a Panasonic AC-160 to a Sony FS700 with a couple of Canon lenses and so far everything has been fantastic. Obviously with such a change in camera my footage looks leaps and bounds forward on what I was providing in the past.

Although last week I hit my first problem..... I film a lot of mobile phones for one particular client and when I was using my new Macro lens I was getting a strange line across the screen.

Now I have been filming phones for a few years now and obviously have had to change my shutter speed to adapt to the the refresh rate and stop strobing but no matter what I do this problem doesnt seem to go away.

I am shooting with a FS700, EF-E Mount Speedbooster with a Canon EF 100mm f2.8L Macro lens.

Whenever I get below a focus of 2 feet the line appears: imgur: the simple image sharer

I have tried lots of different settings and as I said above 2 feet its fine and with my other lens (24-70mm) I dont see the line. Am I being really stupid and it is a refresh issue or is there something that can be done?

Any help/suggestions appreciated

Cheers

Re: FS700 With Macro Lens Issue
 

Hmm... looks like a refresh issue to my uneducated eye. How much trouble would it be to shoot beyond two feet and crop in post? Welcome to DVi by the way.

Re: FS700 With Macro Lens Issue
 

Sorry I thought I should add what the exact settings where

1080P, 25 FPS, 1/60th shutter speed.

These are the same settings I used on the Panasonic and obviously I know its a completely different camera/lens I had no issues like this so there must be something I am not understanding here.

Yeah, I could do that Chris as it certainly is an option but I bought the macro to give me the ability to get incredibly close to the phone to really show off the detail. Seems I was wrong, oops!

Re: FS700 With Macro Lens Issue
 

Do the lines move or are they stationary?

Can you post a short video clip in addition to the still image?

Re: FS700 With Macro Lens Issue
 

Yep, give me a n hour or so and I'll upload a short video

Cheers guys

Re: FS700 With Macro Lens Issue
 

Link attached. Any other info, questions, suggestions please go ahead :)

Re: FS700 With Macro Lens Issue
 

Try it out in sun with something that isn't electronic. You need to start eliminating things. It could be something weird with the LCD display on the phone at that magnification.

Re: FS700 With Macro Lens Issue
 

It doesn't look like a screen refresh issue to me, it looks more like a polarisation thing - it may be related to the OLFP in the camera, I dunno. You could try shooting through a polariser, see if that makes a difference.

Re: FS700 With Macro Lens Issue
 

That is coming from the polarizing screen on the LCD.

Re: FS700 With Macro Lens Issue
 

Hey guys

Thats a good shout. I never thought of that.

Are there any particular things I should look at for a polariser or should I just buy a multi pack of different strengths and see which one works best?

Re: FS700 With Macro Lens Issue
 

Polarisers don't really come in different strengths (well, they do, but it generally reflects brand quality more than anything) but if you have a pair of polarising sunglasses you could try shooting through them. But, if I'm honest, I suspect it will make it worse rather than help.

Just out if interest - that's not some sort of glasses free 3D screen on that phone is it? I'm just wondering why it might do that. I shot a macro shot of a mobile (iPhone) for a viral end of last year and had no problems with the screen.

Also, have you tied varying the angle you shoot it at? Eg straight down, more acute etc

Re: FS700 With Macro Lens Issue
 

Nope just a regular Sony Xperia Z2.

I'll do some more tests on this weekend and get back to you. In the process of picking up a polariser to see what effect it has

Re: FS700 With Macro Lens Issue
 

Anything to report? It's be interesting to know if you found a solution in case I encounter it myself at some point.

Re: FS700 With Macro Lens Issue
 

Looks like aliasing and moiré to me. As you get closer to the screen the camera is able to resolve the individual pixels and this can lead to aliasing and moiré. The phones in the images are not perfectly parallel with the camera so the actual point of sharp focus will be a narrow band across the phone's display. If you fractionally de-focus the picture does it go away or move forwards/backwards along with the focus point? A touch of diffusion with a soft focus filter would fix it. I guess you previous camera wasn't sharp enough to show this effect up ;-)

Re: FS700 With Macro Lens Issue
 

good call Alister! Looking at it again, I think you're right.

Re: FS700 With Macro Lens Issue
 

Hey

My polarising filter arrived yesterday so I will do some test shots today and get them up later to see what difference that makes.

Thanks for replying Alister. You are right regarding the parallel point, I was going to experiment with angles last today as well and yes you are correct as I change focus the line moves backwards and forwards.

Sorry to seem stupid again but do you recommend a certain soft focus filter or are they pretty universal?

Thanks guys!

Re: FS700 With Macro Lens Issue
 

Alister's beaten us all to it - yes, it's Moire: you're going into Macro mode, the screen is very high resolution, but at some point the two resolutions are going to interfere.

It's an awful fact of life, but in these situations (filming LCD screens in general) it's going to bite you, and blurring in post isn't going to help. Blurring in production - just by a teeny weeny bit - will save bacon. Take solace in the fact that your lens and sensor are 'too good' LOL.

I have to film a lot of screens - if I need clean results, then a screen capture app running on the platform (or on a desktop emulator) is the way to go, even if it means a bit of 'faking it' in post. FWIW, I get a lot of trouble with Samsung screens, for which you really need ECS (Electronically Controlled Shutter, or your brand's equivalent thereof) to fine tune your shutter speed to get rid of travelling bands on the screen. This moire problem is about shunting the focus off by just enough to lose the pattern, but this can limit the angles at which you can shoot.

Just a £0.02p thought...

Re: FS700 With Macro Lens Issue
 

I only got totally confused and ordered the wrong size polarising filter. Damn late nights!

Made sure I ordered the right size soft focus filter so I'm looking forward to this arriving tomrrow. I was doing some other test shots and I'm even getting the line across the back of the phones..... This is very bad news haha.

I'm going to film some tests after I post this so I should have something to share later on.

Cheers

Re: FS700 With Macro Lens Issue
 

Having just used the macro lens to look at a particularly patterned cushion I am getting the same line going across as I pull focus so I guess we can confirm this is a moire issue.

I'll upload all of this stuff later today