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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 :)

Camera testing and comparisons

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I would take it back a few posts and concur that all frames should have been posted for a comparison.

I understand that not posting frames may have been easier, and that nobody is paying Geoff, but it makes it impossible for the audience to arrive to their own conclusions. Self evident stuff really.

The impact is aggravated since this comparison was specifically designed to include people that don't know how to color correct, etc... to include people that aren't technically savvy.

Many of these folks already jumped to the conclusion that Red is useless beyond what we see here.

I hope that is the case Geoff, otherwise a portion of the multitude that was overwhelming the server has already been misled.
 
Roberto Lequeux said:
I would take it back a few posts and concur that all frames should be posted for a comparison.

I understand that not posting frames may be easier, but it also makes it impossible to arrive to your own conclusions. Self evident really.
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Robert agree!!!

And because R3D is just a metadata it's possible to get image in a very usable, successful and workable

condition even if what-you-see-is-what-you-get on set monitor observing is not satisfy you immediately.

Advantage RED1 MX because of R3D RAW sort of push or pull wide variant option...

Also with my HDRy ("Ypsilon") approach (that was not beloved here by some of the moderators) you get even more out of RED1 MX footage deeper in shadows and highlights...

I can really guarantee that and just waiting for CML R3D files but still can't download any...???!!!
 
For starters... looks like DRX is off. I can't download the R3Ds to see what's going on here. Unfortunately... people make judgments on these presentations.

Jim
 
Roberto Lequeux said:
Just to clarify, Martin is likely referring to an other post which was deleted at the same time.
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Yup. It was my post. I was merely stating that Geoff's test does not qualify for comparison when he is clearly not rating the camera as suggested by RED even though that is stated on his website.
 
R3Ds still seem unavailable, although they are listed.

Now that I fully understand Geoff's reasoning for not including the top and bottom RED frames, I think it is better to have them there then to not have them there. Otherwise, it looks like RED just falls off the map, i.e. goes straight to complete whiteout or goes full black across the whole image. And based on the steps, we know that can't be the case.

I believe Geoff's intent is good. It's a lot of work. There are a lot of variables. This is one man's test (an excellent DP). In my humble opinion, the tests that are most effective are actually the ones that focus on one camera at a time. They are exhausting for sure, but you throw a lot of scenarios at the camera and you find out where it excels and where it falls apart. And then you profile everything in between. And of course, with these types of cameras that are malleable in post, you must test that side of things to understand the full capabilities.

When I referenced that ISO isn't everything earlier, what I was getting at is if you lock yourself into thinking that one ISO is the end all be all, you will limit the capabilities of the camera, rather than judging based on the needs of the scene. So without saying whether Geoff was right or wrong setting the camera at 400, I do feel comfortable saying that 800 is not the right answer all of the time.

I look forward to checking out the R3Ds.
 
Whatever I set the camera at has F'all effect on the RAW image, it's just altering the metadata.

All that effectively happens is that the "normal" exposure moves up or down the comparison point.

I was using the 400 setting because I was testing a range of cameras that have effective internbal ratings of 200 to 800, by using the midpoint I would be able to see up and down, it doesn't make any difference to the image I shoot.

I can re-render all the RED material with RED CineX rated at 800 and the overall exposure range shouldn't change.

Oh and Sanjin, you got me! I really went out of my way to screw up the RED results, as everyone knows I have a vested interest in...err...oh yes, making pictures and I don't give a flying fart what camera I use. As for criticising focus on a colour and latitude test, grow up!

I knew I shouldn't publish these, or at least not share them here.

I checked how I should output them with both Jim and Arri, I did what they asked.
 
Jannard said:
For starters... looks like DRX is off. I can't download the R3Ds to see what's going on here. Unfortunately... people make judgments on these presentations.

Jim
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Jim, tell me what you want me to set RedCine-X at and I'll redo it all.

I've just checked downloads and I can download the R3D files here.

In Windows right click on the links and save as...

I'd have loved to have included an Epic but that wasn't possible...

Neither was ARRI RAW possible.
 
Geoff - I don't have a problem with the fact that the Alexa has more dynamic range than the RED MX; all tests I've seen proves that point. Also - I appreciate the fact that you make pictures and have nothing vested in either Arri or RED. What I'm getting at is that there's a difference in rating a camera at either 400 or 800 asa and throwing a given amount of light against it based upon that (and I mean 'rate' as in measured light by a light-meter - not the actual setting in-camera... I know what RAW is about). Rating the camera at 400 means you are favoring the lower end and not protecting the highlights.

I'm sure you have Jim's phone number so please give him a call and make sure settings are correct. There's definitely something weird going on with the files. All I'm asking for is that you're fair if you're comparing. I hope the die-hard Arri fans are watching too so the Alexa can shine as much as possible too.

I also can't download the R3Ds here. Might be a server mime-type issue?
 
Tony,

If this were one composition, then I'd agree with you. But that's not the case.

In half stop increments, Geoff:

1) Composed for 400 at f22 and opened the iris to 2.0, causing the image to blowout.

2) Composed for 400 at f2.0 and stopped down the iris to 22, causing the image to fall into black.

3) He concatenated these two sets of images to create a range of exposures.

If I've understood Geoff's methodology correctly, that range of pictures accurately captures 14 stops dynamic range of the sensor.

So it does not matter what rating you give the camera b/c you're killing the image on both directions and counting how many half stops it took to do that. All rating the camera at 800 would have done is add a stop to the top and remove a stop from the bottom. But the total number of stops would have stayed the same, AFAICT.
 
With this particular test it does not matter what the camera is rated at because you are exposing all possible exposures and see what it looks like. If you were to correct all the over/under exposures back to normal in CC, setting the 18% gray chip to 50 IRE, you can determine what you think the best ISO for the camera is.

I think the main reason Geoff doesn't correct the images back to normal in any of his posted camera tests is because that allows you to take that test footage and put it through your own CC process to determine what you think is the optimal ISO is. Every project is has a different look so this would help you learn what ISO produces what look.

Granted, you would want to use the R3D files to do that. But posting DPX versions of them allows us to get an idea of how much flexibility the footage from each camera has, in comparison to eachother.

Jim I was under the impression that DRX only helps DR minimally, noticeably but still not that much. With Geoff's methodology of not posting the images that were too dark or too bright to be worth while to post, there's 4 stops of exposures missing... I didn't think DRX was magical enough to extend DR 3-4 stops combined over/under... I thought it would only extend maybe 1 stop on the top end, in certain channels?
 
geoffboyle said:
Jim, tell me what you want me to set RedCine-X at and I'll redo it all.

I've just checked downloads and I can download the R3D files here.

In Windows right click on the links and save as...

I'd have loved to have included an Epic but that wasn't possible...

Neither was ARRI RAW possible.
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Geoff,

The links to the source files still don't work. They would be helpful to have, if for no other reason, then to give you file and timecode settings to fill in the rest of the chart for the Red and Alex (709) images at the extremes.

The problem with leaving the chart as it is is that you are not showing the darkest (less obvious) and lightest (very obvious) images for the Red, but you are for the Alexa Log footage. The Alexa 709 footage also does not go plus and minus seven stops but still shows more extremes than the Red 709 footage does. So as presented right now, the chart is quite simply misleading.

I realize you stopped when you could no longer make out the exposure info on the bottom. But it's much easier to make out the exposure indicator on the last extreme Red images than it is on the last extreme Alexa images. (I've attached examples.)

I have to think it's possible to add additonal images for the Red (and the Alexa 709). If you can't identify them, perhaps we could assist by giving you the filename and timecode? Which is one reason why the .R3D's would be helfpul

Also, I don't believe there was any kind of bias in the test at all. In fact, if you went through 4:2:2, that actually hurts the Alexa footage. I think these things are just very difficult to do. So thank you very much for the effort.
 

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geoffboyle said:
Oh and Sanjin, you got me! I really went out of my way to screw up the RED results, as everyone knows I have a vested interest in...err...oh yes, making pictures and I don't give a flying fart what camera I use. As for criticising focus on a colour and latitude test, grow up!

I knew I shouldn't publish these, or at least not share them here.
Click to expand...

Geoff, from what I understand it is a fair test, personally I can't see anything wrong with it.

People here might be disappointed that the Red One MX doesn't fare better against the Alexa. I was under the impression that the latitude difference would be 1/2 to 1 stop but this shows an entire different picture. So don't take it personally if people are not happy with the test, it's not about you.

And don't take Sanjin serious.

I still hope there is some information in the R3D files that we are missing but downloading the R3D's seriously doesn't work. Any way you can fix that?
 
I wonder if artists back in ye olden days argued over whose pencils and oils were best?

:wink:
 
Geoff,

Geoff,

You're doing a good job, and trying as hard as you can to make everyone happy. This is RED's house so of course poeple here will have a singlar focus. Do you best and then forget about it.

Jay
 
sander kamp said:
Geoff, from what I understand it is a fair test, personally I can't see anything wrong with it.

People here might be disappointed that the Red One MX doesn't fare better against the Alexa. I was under the impression that the latitude difference would be 1/2 to 1 stop but this shows an entire different picture. So don't take it personally if people are not happy with the test, it's not about you.

...
Click to expand...

Sander,

The test is perfectly fair, FWICT. But your impression illustrates why it's current presentation is probably not.

You are seeing a huge difference in terms of DR between the two cameras. Probably FOUR stops, b/c the the Alexa Log has eight more half-stop images than the Red MX Log has.

Well I don't believe Geoff is claiming anything near a four stop difference. He simply didn't post the extreme images for the Red (or the Alexa Rec 709) b/c it was too difficult to make out the exposure information at the bottom of the images.

That does not mean that an extreme Red image is equally blown out or black as an extreme Alexa image is. And I'm sure Geoff would agree with this statement (I don't mean to put words in his mouth).

Look at the examples of the highlight extremes for the Red and Alexa 709 images that I attached in post #74. Tell me with a straight face that they are equally blown out; that you see no difference between them. You cannot.

CLEARLY, the Red image has more detail and color. This is simply not up for debate. It's a fact.

So when you look at the chart and think that the Red Log footage is blowing out at plus four stops while Alexa Log is blowing out at plus seven stops, that's simply not the case. What is the case is that Geoff, b/c of the difficulty of making out the EI indicator at the bottom and having lots of more work to do on top of all the work that he's already done, did not include the extreme Red (or Alexa 709) values.

I highly doubt he intended anyone to think that the lightest Red image is analogous to the lightest Alexa image, when our eyes show that is clearly not the case. And I don't think he intended people to look at this comparison and say "WOW, ALL those other tests showing maybe a stop difference were horribly WRONG! The difference is actually FOUR STOPS!" That is nonsensical, and the images don't show that*. That said, adding more extreme Red and Alexa 709 images would make it much more difficult for someone to jump to conclusions based upon how many squares they can count.


P.S. I hope I haven't put too many words in Geoff's mouth, LOL! And thanks again Geoff.

* I want to add that one could say that the test shows perhaps a 2.5 stop difference in the Log workflow footage.
 
Sanjin Jukic said:
In that case Alexa probably was more accurate focused at the lens, could be a sort of test trick in favor to Alexa just because RED has always razor sharp image.
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Sanjin,

Really?

Why do you have to suggest a conspiracy against RED?
Why would these working pros defocus the lens?

There is no credence to these kinds of "in the air" accusations and they create a air of mistrust with no foundation.

David
 
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