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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 :)

Chromatic aberration

S

Steen Linde

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Hi Red-guys

Do you have any experiences with chromatic aberration using the camera with the available lenses.
I shoot a lot in HD, and here you see it all the time.


Steen Linde
__________

Picturewise Film
Denmark
 
Steen Linde said:
Hi Red-guys

Do you have any experiences with chromatic aberration using the camera with the available lenses.
I shoot a lot in HD, and here you see it all the time.


Steen Linde
__________

Picturewise Film
Denmark
Click to expand...

chromatic aberration is a problem of 3 CCD cameras - not a problem of single chip systems...
 
It can absolutely be caused by a lens. It also can also occur with an inadequate low pass filter.
 
Although we don't have prism issues, the sensor is capable of showing what's going on in the lens, so you will be able to see some aberations, as lenses are not perfect. But you don't get prism artifacts.

Graeme
 
Cromatic aberration 2

Cromatic aberration 2

It is often a lens problem. Take a look at the foto Mr. Jannard took a while ago. This kind of CA I often see when I shoot in HD or with a DSLR, with different lenses,espesially wideangels.
If I use Digiprimes from Zeiss you don`t see this very often. I know there is a big difference in price ,but I'm curious to know how the CA is with the Red camera.

:)

Steen Linde
__________

Picturewise Film
Denmark
 
Hello Steen,

I am not certain that I agree that your indicated points are CA ones and not a result of conversion to .jpg, I would want to see a .tif before making this leap.
 
Steen Linde said:
It is often a lens problem. Take a look at the foto Mr. Jannard took a while ago. This kind of CA I often see when I shoot in HD or with a DSLR, with different lenses,espesially wideangels.
If I use Digiprimes from Zeiss you don`t see this very often. I know there is a big difference in price ,but I'm curious to know how the CA is with the Red camera.

:)

Steen Linde
__________

Picturewise Film
Denmark
Click to expand...

hmm... that doesn't look like any CA I'm used to seeing.
 
Cromatic aberration

Cromatic aberration

wshultz said:
hmm... that doesn't look like any CA I'm used to seeing.
Click to expand...

What would you define these lines of different color as... ?

Best regards

Steen Linde
__________

Picturewise Film
Denmark
 
It's CA, but it's not left-right CA, but circular. You get it on most lenses (well, all I've used, but I'm not a lens guru) when it's wide open. It's the light focusing at different depths for different colours.

Graeme
 
In the soon to be released film ”The Assassination of Jesse James by the Coward Robert Ford” the DP Roger Deakins used some antique lenses that had extreme chromatic aberration - it looks beautiful.

I can't find a still showing the effect of it, but the film is worth seeing on the big screen.

I'm not arguing that modern lenses should have any CA if it can be helped...

Matt Uhry
www.mattuhry.com
 
Hi Matt

I did a few camera day calls on that film. It was done a long time ago and I heard it was so screwed up by the director that they had to do a ton of work on it with re-shoots and post so thats why it took so long to release.
 
From what I heard, the Jesse James movie was not so much "screwed up by the director" as the studio expected a highbrow action pic and the director delivered a slow, meditative drama that had a runtime of 3 hours. Probably a better film in the end, but much less commercial then hoped for.

Come to think of it, I suppose that depending on the point of view, that could constitute "screwing up." I've heard, though, that the final cut is pretty close to the director's original cut, and it sounds pretty good. I'll be seeing it for sure when it comes out in a few weeks.
 
Re the RED lens 15-50mm - we professionally tested this lens independently for our up coming fxphd course and (which involves mounting it on a projector etc) I was looking for exactly this as it effects effects keying so much, and we found none.


Mike
 
JasonMurphy said:
From what I heard, the Jesse James movie was not so much "screwed up by the director" as the studio expected a highbrow action pic and the director delivered a slow, meditative drama that had a runtime of 3 hours. Probably a better film in the end, but much less commercial then hoped for.

Come to think of it, I suppose that depending on the point of view, that could constitute "screwing up." I've heard, though, that the final cut is pretty close to the director's original cut, and it sounds pretty good. I'll be seeing it for sure when it comes out in a few weeks.
Click to expand...



Well what I can tell you for sure is when I read the script it was pretty acurate to jessie james life from the white pages of shooting and not fast paced. If the studio or producer could read it and not see that the movie would be slow they would have to be total itiots so I doubt anyone from the studio that was remotely attached to the project would have thought it was going to be a young guns flick. I suspect someone lead you wrong with that information Jason.

Also reports I heard is in post the director drove the studio crazy and they were unhappy with their choice in him because he was so difficult. This would not suprise me as I know many of the actors were totally frustrated with the director. I saw on 2 seperate ocassions both Brad Pitt and Casey Affleck very upset with him. On both occasions the director had pushed the take count over the 30's "Casey was finally yelling tell me what you want for a performance and I will give it to you"and when it happened to Pitt "he started saying look I can give you what ever you want you just have to make up your mind" until finally Bad told the director "This next take is what I feel it should be so you get this last one and I am done" Brad then proceeded to give the performance gave his own cut and walked straight off set. These are just a few things I saw and I was just called in for extra camera day shoots. Now I know one of the directors tools is multiple takes to get an emotional performance but from what I saw and the rest of the crew thought it was simply a new director over his head that really did not know what he wanted.

I hope the film is good too Jason but if it is good from what I heard and saw it will not be due to the director.
 
It's really slow and meditative, more like a Tarkovsky film than anything else. The performances were great, Brad Pitt won best actor for it in Venice, so I guess it's working out for him. I loved it at times and other times was kind of wondering when the story would get on... The directors last film "Chopper" is well regarded. I guess I should watch it and get some context.

Lots of Oscar heat on the pic.

Matt Uhry
www.mattuhry.com
 
Can anyone tell me if this is CA that Im looking at around the blown out window edges??
This is an Leica Summilux 80mm @1.4 maybe 6 to 10 feet from subject.
And is this normal or acceptable for the conditions. This lens just got back from being Cinevised so that is why I was running the test.

I know its in to a totally blown window but this was a test to see what is going on and how the lens would handle these conditions.
and yes the lens doesnt seem to do the edging or CA problem when not shooting directly in to a over exposed window but just wanted a few folks to let me know their thoughts.


Green edges.0002272.jpgBlue edges background in focus.0000357.jpg
 
That's CA. Situations like that where you have bright light against hard edges are usually where it's easiest to see. Nearly all lenses will have at least some noticeable CA when wide open, but it should disappear when you stop down.
 
Thanks Alan, I was kind of freaking out a bit as I just got the lens back and though that this amount of CA was kind of a lot for what kind of glass it is. But I guess this test is at the extreme of the lens capabilities. Started to think about HDRX when I shot it.
Any other comments would be welcome.
What do you think... stoping down to say 2, 3.5 would start to minimize it?? I know it wont go away in these conditions but at least keep it under control.
 
It varies from lens to lens, so the only way to know for sure is to do your own tests at different stops. Yours really didn't look all that bad for a f/1.4 exposure - the Zeiss 85/2.1 looks worse that that wide open, and some of my old Nikkors have some noticeable red/green shift at f/5.6. If you look at the SALT III test (stickied at the top of this forum), you'll see that all but the most expensive cine primes will get some colored fringes around shiny objects.
 
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