Jump to content
Phil Thompson

Issues with a a Spirit 2K scan

Recommended Posts

Hi all,

 

I have a question. I've had a couple of scans done by a company that has a Spirit 2K scanner. The DPX files when viewed in Nuke (or any other viewer) displays these faint lines in the background. (see attached). When the footage is moving it's not *so* visible but I assume this isn't normal as footage from a different post house never displayed this effect.

 

Can ANYONE shed any light on to this?

 

https://images.creativecow.net/221967/test3.jpg

https://images.creativecow.net/221967/test2.jpg

 

Yours sincerely

 

Phil

Share this post


Link to post
Share on other sites

Yes sorry, to Clarify I'm not talking about the scratch. I'm talking about the horizontal striping. Any idea of the cause of this? I'm pretty sure it can't be the neg as this has happened to two batches now.

Share this post


Link to post
Share on other sites

Hm. I see what you mean. It's subtle but it's there. Fixed pattern noise, more than anything else.

 

I hesitate to offer any sort of of opinion based on no information, but it really does shriek scanner fault. Does it change in parts of the scan that show (for instance) near-black or near-white stuff, stop flashes and roll ends etc?

 

P

Share this post


Link to post
Share on other sites

yes it looks like Fixed pattern noise. What would you do in my situation? I've emailed back the Scanning company with Stills.

Where do you reckon I Stand? I think they have a North light scanner too. I guess I could ask them to try on that. (though they say it will cost a lot more). This is so annoying. Do you know anywhere with a 2K Spirit that don't charge 50p a frame. These guys were doing 1500ft for 200 quid which seemed 'ok'..

Share this post


Link to post
Share on other sites

It's not really your problem to figure out why. First ask (nicely and calmly) about the problem.

 

What I'd do is scan just a few frames of the material on another scanner, which would isolate the problem to the scanner, as opposed to it being some obscure camera or processing issue. Many digital imaging devices have the facility (not to say requirement) to do calibration on the sensor, but I suspect that's not what's going on here. If this is 16mm, and if (say) the per-pixel black level calibration was off on a any line-array telecine, you'd expect to see vertical streaks, not horizontal.

 

I can't claim to be an expert on the low-level workings of the Spirit, however, and there are many associated issues that might arise. The thought occurs that any form of vibration or chatter in the transport could create this sort of mess, by affecting the speed of the film as it passed over the sensor. I'm speculating, of course.

 

I notice that if these are 1:1 pixel representations of the scan, the noise pattern seems to have a period of about 16 pixels, but really that's just idle speculation. Call the people who did it and (nicely) ask.

 

P

Share this post


Link to post
Share on other sites

The FPN function will filter out the lamp and lens shading not horizontal noise. If the noise pattern is horizontal, check if it is within one color only (RGB). If so there might be a problem with the sensor since that is a line-array; If it is on all three color channels, it might be power supply or something common to the three channels.

A rescan is definitely required.

Share this post


Link to post
Share on other sites

I see this when a telecine light is pushed too far from dark material. I'm seeing it more and more though. I'm wondering if it's a sign of aging telecines.

Share this post


Link to post
Share on other sites

Sometimes when line scan telecine or scanners get dirt or dead pixels on the line (because it's a line this becomes a streak through the picture) you get this it is something that probably requires a professional cleaning of the optical block.

Share this post


Link to post
Share on other sites

I have seen this problem with a customer's 16mm film that Cinelab developed that was 2K scanned on a Golden-Eye scanner, it is a problem that can occur in ANY Line scan machine.

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.



  • Wooden Camera



    Visual Products



    Ritter Battery



    New Pro Video - New and Used Equipment



    Glidecam



    Gamma Ray Digital Inc



    Tai Audio



    Serious Gear



    Media Blackout - Custom Cables and AKS



    Metropolis Post



    Rig Wheels Passport



    Paralinx LLC



    CineLab



    Abel Cine



    Broadcast Solutions Inc


×
×
  • Create New...