Ursa Mini 4.6K dynamic range (Cinema 5D)

[AlexTrinder96]

https://***URL not allowed***/blackmagic-raw-dynamic-range-on-the-ursa-mini-pro-4-6-tested/

 

Compared against Pocket 4k, FS7 and XT3! 

[thebrothersthre3]

Yeah, as I suspected. Their numbers are lower then most companies claim. So 11.2 stops seems really low on the XT3 but when they are rating the FS7 and Ursa Mini at under 13 stops, that changes it. 

[AlexTrinder96]

Just now, thebrothersthre3 said:

Yeah, as I suspected. Their numbers are lower then most companies claim. So 11.2 stops seems really low on the XT3 but when they are rating the FS7 and Ursa Mini at under 13 stops, that changes it. 

And that's why I doubt Z cams claimed 15 stops; usable stops is what matters!

[thebrothersthre3]

Just now, AlexTrinder96 said:

And that's why I doubt Z cams claimed 15 stops; usable stops is what matters!

Yeah I don't think they are using Cinema 5d science to measure it. If it has similar or slightly higher DR then the Ursa 4.6k I'd be happy though. 

I want to see Cinema 5d's DR number for the Alexa. 

[AlexTrinder96]

I would be surprised if the Alexa wasn't at least 14 tbh! I've used the Alexa mini, alongside the Ursa 4.6k and it definitely has better highlight rolloff and less shadow noise! 

[KnightsFan]

11 minutes ago, thebrothersthre3 said:

Yeah I don't think they are using Cinema 5d science to measure it. If it has similar or slightly higher DR then the Ursa 4.6k I'd be happy though. 

I want to see Cinema 5d's DR number for the Alexa. 

C5d puts the alexa at 14 using their SNR = 2 measurement.

16 minutes ago, AlexTrinder96 said:

And that's why I doubt Z cams claimed 15 stops; usable stops is what matters!

I agree. But you cant blame z cam when everyone from sony to blackmagic exaggerate their dr. Only arri has the godlike status that allows them to be honest and still sell products.

[IronFilm]

That guy Clayton Burkhart is arguing hard in the comments to make a case for the Sony F3's dynamic range. 

 

https://www.abelcine.com/articles/blog-and-knowledge/tutorials-and-guides/s-log-and-the-sony-f3---part-1-on-the-charts

[AlexTrinder96]

Also noticed they didn't do a black shade...It defo makes a difference!

[IronFilm]

1 minute ago, AlexTrinder96 said:

Also noticed they didn't do a black shade...It defo makes a difference!

C5D has to keep up their past strong track record when it comes to unreliable/conflicting/confusing dynamic range test reports! ?
It just wouldn't be normal them if they didn't have something like that.....

[sanveer]

38 minutes ago, IronFilm said:

C5D has to keep up their past strong track record when it comes to unreliable/conflicting/confusing dynamic range test reports! ?
It just wouldn't be normal them if they didn't have something like that.....

I think they do it as a private joke for themselves or they are genuinely never reliable. I actually suspect that they would have tested the Alexa at UNDER 14 stops, but are too afraid to publish it. The Alexa standard being indisputable, they would probably invite a plethora of brickbats. Almost as ludicrous as that 14.6/ 14.7 stops of Dynamic range on the Panasonic GH5s done by that freak which was published by NewsShooter.com. Cinema5d measured the same camera's dynamic range at 10.7 stops, 4 WHOLE STOPS less. If their measurements differed by 4 stops on the Alexa, one of those sites would have shut down. 

It is indeed an amusing world.

[deezid]

2 hours ago, sanveer said:

I think they do it as a private joke for themselves or they are genuinely never reliable. I actually suspect that they would have tested the Alexa at UNDER 14 stops, but are too afraid to publish it. The Alexa standard being indisputable, they would probably invite a plethora of brickbats. Almost as ludicrous as that 14.6/ 14.7 stops of Dynamic range on the Panasonic GH5s done by that freak which was published by NewsShooter.com. Cinema5d measured the same camera's dynamic range at 10.7 stops, 4 WHOLE STOPS less. If their measurements differed by 4 stops on the Alexa, one of those sites would have shut down. 

It is indeed an amusing world.

That messed up test was done by the EBU.
Almost nothing they did over there made any sense.

[thebrothersthre3]

To be fair I believe Cinema 5d used Vlog to test the GH5. People have said HLG results in higher dynamic range. 

[KnightsFan]

So those of you who think C5D's results are inaccurate, what do you think is causing that? Are they intentionally lying? Is the imatest software glitching out? They publish their methodology, and the images they use with imatest. Are the images fake?

They've even gone out of their way to explain different ways of testing dynamic range (https://***URL not allowed***/canon-measured-15-stops-dynamic-range-c300-mark-ii/) and now they often publish at least two values, for SNR = 2 and SNR = 1. These are not subjective tests. You can very easily copy them--they explain the setup, the lens used, the exact ffmpeg command to extract i frames, and how to setup the software. If you cannot reproduce their results with the same setup, then publish your results and let us know. But until then you really have no authority to call BS.

Do you really think they would go through the trouble to be the only site that conducts extensive, objective DR tests, and then make up their results? If so, it should be very easy to prove, instead of bashing them on internet forums.

[sanveer]

23 minutes ago, KnightsFan said:

So those of you who think C5D's results are inaccurate, what do you think is causing that? Are they intentionally lying? Is the imatest software glitching out? They publish their methodology, and the images they use with imatest. Are the images fake?

They've even gone out of their way to explain different ways of testing dynamic range (https://***URL not allowed***/canon-measured-15-stops-dynamic-range-c300-mark-ii/) and now they often publish at least two values, for SNR = 2 and SNR = 1. These are not subjective tests. You can very easily copy them--they explain the setup, the lens used, the exact ffmpeg command to extract i frames, and how to setup the software. If you cannot reproduce their results with the same setup, then publish your results and let us know. But until then you really have no authority to call BS.

Do you really think they would go through the trouble to be the only site that conducts extensive, objective DR tests, and then make up their results? If so, it should be very easy to prove, instead of bashing them on internet forums.

I could help you understand it, but I am guessing it would be better if you simply did a Google search of atleast 10+ random test results of Cinema5d doing dynamic range tests. It could include any and every camera you can think of. Check the history of the results over a few years and all your doubts will be answered.

Your defence of them is either ernest and genuine ignorance or something much worse. Either ways, only you can answer your own doubts. Anything else would be an exercise in futility. 

[KnightsFan]

@sanveer Last time we talked about this, I actually did that. I looked up every single C5D article that mentioned a dynamic range and compiled them into a spreadsheet. Turns out the only discrepancy was with the A7s2. I contacted C5D about that, and was told which articles had used a 4k to 2k downscale. The 4k downscale increases DR on the A7s2 from about 10.6 to 12 stops. After that was cleared up, I couldn't find any other significant problems.

Now, it appears that they always list the resolution and whether any downscaling was done.

[sanveer]

1 minute ago, KnightsFan said:

@sanveer Last time we talked about this, I actually did that. I looked up every single C5D article that mentioned a dynamic range and compiled them into a spreadsheet. Turns out the only discrepancy was with the A7s2.

You obviously didn't search properly or even sufficiently. Unfortunately. 

[KnightsFan]

C5D DR Tests.xlsx

Feel free to check. I haven't added the 4.6k article from this topic yet.

[KnightsFan]

Though, discussing C5D's past accuracy is slightly off topic. The real question is, if this test is bogus, what is the actual dynamic range of the Ursa 4.6k?

[webrunner5]

Well to their credit they have changed the equipment they use to test with, and as we see it all seems a lot lower for every camera they have tested, or re tested. Now is it completely true DR I don't know. But at least it is a consistent test, much like DXO is. Like it or not I think it is more realistic than the manufacturers state, and a lot of silly stuff on YouTube from some Vlogger.

[sanveer]

1 hour ago, KnightsFan said:

C5D DR Tests.xlsx

Feel free to check. I haven't added the 4.6k article from this topic yet.

Whoa. That was a long and wide compilation. Maybe I'll check it tomorrow sometime. Maybe if you added the date to the tests it would help one understand whether they were conducted around the same time, under different profiles, or over different periods of time when their methodologies and co cousins varied. 

1 hour ago, KnightsFan said:

@sanveer Last time we talked about this, I actually did that. I looked up every single C5D article that mentioned a dynamic range and compiled them into a spreadsheet. Turns out the only discrepancy was with the A7s2. I contacted C5D about that, and was told which articles had used a 4k to 2k downscale. The 4k downscale increases DR on the A7s2 from about 10.6 to 12 stops. After that was cleared up, I couldn't find any other significant problems.

Now, it appears that they always list the resolution and whether any downscaling was done.

I read one of the tests which showed the A7s or A7s as having 14 stops. That couldn't possibly have been the improvement from downressing it from 4k to 1080p.