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  • Hey all, just changed over the backend after 15 years I figured time to give it a bit of an update, its probably gonna be a bit weird for most of you and i am sure there is a few bugs to work out but it should kinda work the same as before... hopefully :)

When can I order an Ursa Mini 4.6K??

The magenta issue, I wonder if it is from a reddish (may not be meant to be so much red) filter coating on the glass in front of the sensor.
 
Hey Jake . . . come back to my thread . . . missing your sunshine over there ;-)
 
Wayne Morellini said:
The magenta issue, I wonder if it is from a reddish (may not be meant to be so much red) filter coating on the glass in front of the sensor.
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May just be. Not sure, but BMD said publicly that they're hoping to fix this issue without physical modification. We should all find out in the next couple of months. Here is exactly what they said:
https://forum.blackmagicdesign.com/viewtopic.php?f=2&t=47333&start=1650#p283893

I actually found it surprisingly honest...
 
Fahnon Bennett said:
May just be. Not sure, but BMD said publicly that they're hoping to fix this issue without physical modification. We should all find out in the next couple of months. Here is exactly what they said:
https://forum.blackmagicdesign.com/viewtopic.php?f=2&t=47333&start=1650#p283893

I actually found it surprisingly honest...
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It's also shockingly vague.

Look at the difference btw RED and Raven. Some local users here noticed that the RAVEN had a small "black hole sun" issue.

RED fixed it within three weeks in their next firmware release.

Boom.

Done.

This magenta issue on the Ursa Mini? It's been going on for MONTHS....and looks to remain that way for rest of 2016.

Not not good....at ALL.
 
The black hole issue is likely easy to fix compared to the corner issue.
 
Sensor calibration technique to resolve the magenta issue.

Sensor calibration technique to resolve the magenta issue.

Even despite the potential for performance issues in the compensated areas, the other issue they might be struggling with is if it varies across sensor and from camera to camera, and on the light/image condition (as well as lens).

To do so, might require different colored cards (or caps) at different luminance to get the base mapping data before modeling is applied through a update.

Firstly you calibrate the static problem by sampling on a range of consistent sources to determine the problem, then using modeling from internal testing to see how you should adjust pixels based on the colour and brightness of light, and the lens configuration, you apply adjustments per pixel live. You should be able to obtain an suitable intermediate fix within a day or a week, even if it is not perfect.

This situation may extend until the next batch of sensors/treatnent batch.
 
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Fabio Lanzone said:
Easy to fix? My bmcc has 3 years and the black sun is still there. Raven? 2 weeks and fixed. I love RED
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It has a lot to do with how the sensor is over pushed in areas of extreme exposure, so is more predictable (and frankly adjust upper end sensor performance range might get rid of it). Been a bif problem with Micron sensors in the past on the Ephel cameras, they literally looked like they were under giant black holes. At similar time cameras erred having problems with column like noise patterns because they pushed the sensitivities too far I think. I thought they firmware patched that. Is yours still got snnissue?

The magenta problem is another potential unweildly problem.

But as you indicate, Red and likely their sensor partner, are much more ontop of these things (though I believe the Red One sensor performance was not as expected when compared to previous pre camera samples posted they were aiming at. But was probably meant to be closer to the mx. So, things take time to get as good and quick at as Red is.
 
I must say though, BM has had an unusuual string of sensor issues. The black hole and column like noise (understood for years) the glass, maybe a coating here, or not. All these things should have been avoidable, testable before final production, at the suppliers side before BM for the cameras, at the start and regular intervals of the production of components, so (except in manufacturing the sensor itself) production could be halted and corrected, some of the bad parts disposed of.
 
The reason why BMD can make cameras as cheaply as they do is probably because they do minimal QC. That's why they now have such a bad history. You're right; these problems have all been pretty avoidable, but not if you're charging low-thousands for cameras like theirs. Some people are happy to take the risk because it means they have access to a cinema-caliber image for such a low premium. But there is real risk involved, and eventually you'll get burned.
 
Blind am I:

https://www.blackmagicdesign.com/au/support/readme/c48cf4ff56a5495990822e854f50ecc7

Can even see it in their webpage photo. Was about the only one to talk about Red skin handling issues back in the mx days here.

Now, we ate talking, if they can make it comparable to Raven in picture rendering it will be great (except for the price over here).

The BM keeps going up in price here, and craft is just bit good enough. A Red camera phone might be nearly as good rendering at half the price to setup the camera with new lens.

Can anybody please offer a shooting workflow handeling comparison between the Mini 4.6k and the Raven? Thanks. At the price they want it is time to wait for the dollar to spike and buy a Raven. The craft will probably win for value against the 4k.
 
Kenneth C Merrill said:
The reason why BMD can make cameras as cheaply as they do is probably because they do minimal QC. That's why they now have such a bad history. You're right; these problems have all been pretty avoidable, but not if you're charging low-thousands for cameras like theirs. Some people are happy to take the risk because it means they have access to a cinema-caliber image for such a low premium. But there is real risk involved, and eventually you'll get burned.
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It's worse than that, you can get very cheap pocket cameras without these issues. But this is something that could happen, if you hunt around for the cheap suppliers unfamiliar with what you are doing, you are likely to find issues.
 
Nick Morrison said:
It's also shockingly vague.

Look at the difference btw RED and Raven. Some local users here noticed that the RAVEN had a small "black hole sun" issue.

RED fixed it within three weeks in their next firmware release.

Boom.

Done.

This magenta issue on the Ursa Mini? It's been going on for MONTHS....and looks to remain that way for rest of 2016.

Not not good....at ALL.
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In all fairness, I'm not sure that's an apples to apples comparison. For instance BMD had the black hole sun issue with the pocket camera and fixed that fairly quickly with a firmware update as well and have not had it on any camera since. The magenta issue looks like a much larger problem; one that they only recently have figured out a plan to fix.

And apparently Red has not figured out this pattern of orbs that happens in flares when shooting at smaller apertures that folks reported in at least 2013.
http://www.reduser.net/forum/showth...erator-issue&p=1638221&viewfull=1#post1638221

The part about it looking like the URSA magenta corners problem remaining that way for the rest of 2016 is just speculation. You could be right, or it could be fixed later today for all you and I know. I'd bet reality will land somewhere in the middle.
 
Fabio Lanzone said:
Easy to fix? My bmcc has 3 years and the black sun is still there. Raven? 2 weeks and fixed. I love RED
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They've gone on record as saying the BMCC was maxed out as far as processing power goes, and they were not sure if it could be fixed without negatively impacting the image in some other way. They never fixed the BMCC, but they did fix the pocket and haven't had the issue on any camera since.
 
Wayne Morellini said:
I must say though, BM has had an unusuual string of sensor issues. The black hole and column like noise (understood for years) the glass, maybe a coating here, or not. All these things should have been avoidable, testable before final production, at the suppliers side before BM for the cameras, at the start and regular intervals of the production of components, so (except in manufacturing the sensor itself) production could be halted and corrected, some of the bad parts disposed of.
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Totally agree. I'm sure their hand built prototype cameras sent to beta testers were largely free of these issues and the problems started when they went to manufacturing.
 
Fahnon Bennett said:
Totally agree. I'm sure their hand built prototype cameras sent to beta testers were largely free of these issues and the problems started when they went to manufacturing.
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Benton Colins was pointing out magenta splotches/shading in beta footage back in November. The beta cameras were not free of these issues.
 
Kenneth C Merrill said:
Benton Colins was pointing out magenta splotches/shading in beta footage back in November. The beta cameras were not free of these issues.
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John Brawley said the cameras were still being tweaked at the time Benton pointed it out. I was assuming the prototypes were free of the issues when they were mass produced, not all the time during development.

Benton, who's since become a friend of mine, took a real beating for pointing that out. Not sure what happened on BMD's end here tbh. BMD said that they did tweak it but only for f/5.6 and wider. Still a huge fuck up, but that's their explanation. Personally, I comfortably go to f/11 pretty often for daytime exteriors where I don't want a shallow dof.

One thing I'd bet on: BMD thought this issue was fixed before shipping. This is the biggest embarrassment for them and this camera, if it had launched with no issues, would have been the one that got the higher end pros to take notice and start using it as at least a b-cam. Even here, some folks were excited to get their hands on the camera. No way they'd mess with that on purpose, unless they're actually insane...
 
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Have you tried a ND and different lenses for your f11 shots to see if the issue is reduced Fahnon?
 
Wayne Morellini said:
Have you tried a ND and different lenses for your f11 shots to see if the issue is reduced Fahnon?
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Yup. My testing tells me that with the current fw, ND and wider apertures are the way to go for now. Shooting @ 28mm, f/5.6 clean on Contax Zeiss, a Sigma 18-35 and a Samyang.
 
Fahnon Bennett said:
John Brawley said the cameras were still being tweaked at the time Benton pointed it out. I was assuming the prototypes were free of the issues when they were mass produced, not all the time during development.
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There's a few overlapping issues here.

There's sensor shading and then there's what was originally a magenta bias (white point) plus a few users are reporting what BM call asymmetric magenta, usually a magenta tinge on the right hand side of the frame. These three separate issues get all thrown together into a "magenta" issue, but they are all discrete problems that present similar magenta symptoms.

The first two issues are what the recent firmware update attempts to improve on and for some it does seem to have done that. I personally have three cameras, one a hand made prototype which shot the first publicly downloadable footage. No one seems to have found any magenta issues with that footage. I also have two factory made PL mount cameras that were sourced from the local distributor for the show I'm currently shooting on right now. They also seem to be fine and we're using them every day. I haven't even updated to the more magenta free version because I'd have to re-do a whole bunch of LUT's mid-shoot for the show I'm doing and it's not been a problem for me.

I do think that there's an unfortunate issue with some sensors having the so called asymmetric magenta and that shouldn't be happening. As far as I've seen, anyone with a genuine issue gets dealt with fairly by BM. BM have been here before too. Beta cameras and proto cameras performing great and then once they go into production there's hiccups. There was the white orbs with the pocket for example. But they also seemed to turn that around very quickly (it was a couple of months from memory) but at the time everyone started seeing white orbs in all their footage even months after it was addressed. Once there's an idea of a problem users go looking for it, and that's fair enough. And in most real world situations, even pre-firmware update, many users didn't find that there was a magenta problem. On the FB page a while ago, where the magenta issue is discussed a lot, there was a poll and something like 40 users said they had no problem and 2 said they did.

Also it's incredibly naive to say that the original BMCC should have been able to do higher frame rates because the sensor could do it and that BM somehow held that camera back from doing it as a choice. The backend infrastructure to support RAW at higher frames and high bit depth made it impossible with the form factor, cooling and power requirements that it would have taken to do so. Feel free to have a go at BM all you like but at least keep it in the real world. At the time they launched that camera, no other camera at ANY price could do what they did in their very first camera. They designed it very specifically to have a max frame rate of 30fps and a data pipe internally that would support that. Any higher frame rates would have meant an entirely different camera.

jb
 
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