Knee DR and yellow blotches..

I tried to test roll off today here we see super knee (105%) vs 80% knee, certainly "SN" loses a stop or two DR (the images are not the same exposure level) but I think the highs do roll off a little better

First out of the camera and then with the blacks crushed in PS levels

What we really see both images basically drop off a cliff

I do however think my therory that flat profiles have a cost in the 8bit space is correct however

SN
SNGrey.jpg
80
80Grey.jpg
crushed SN
SNGreyCrush.jpg
chushed 80
80GreyCrush.jpg
 
Last edited:
Now that´s scary.

Just came back to my computer after shooting a paper roll with different knee settings including your super knee - and than I saw your post Morgan.
Had the same results.

I starting to sort my PPs with different knee settings now.

Frank
 
Looks like the hard vertex in the gamma response at the knee point is pretty visible in both of those settings, all contrast and detail above the knee point looks pretty screwed up and unnatural. You might want to try some new settings... I played around with this for a while on my FS100 and am pretty sure the knee settings I settled upon and posted in another thread perform better.
 
morgan_moore said:
Postmaster : interesting

nyvz - Ill hunt

- you realise this is serious overexposure on purpose ?

S
Click to expand...

I'm not sure what the part you addressed to me means, but as to overexposure clearly this simple test is used to show how the knee performs and is not representative of a real world scene, but the highlight gamma it exposes is clearly indicative of how one might expect natural highlights to perform in a real scene with any kind of significant contrast. Also, sometimes we overexpose scenes for a particular look or effect, so a test of highlight gamma performance is hardly irrelevant in understanding what to expect from a particular camera or knee setting.

I did a similar test live with a black and white ramp chart and my tvlogic monitor zoomed into 80% near the area of clipping with wfm on to really understand how various knee/gamma settings perform in varying situations. What it really pointed out to me was that there were really only two knee settings for cinematone 1 that I felt were optimal and still neither were perfect and cinematone2 matrix is necessary for maintaining detail and avoiding oversaturation of colors in highlight areas.
 
Last edited:
Indeed im looking at getting the best performance as the camera rolls to blown overexposed white

I place a lot of white in my scenes (see the feet above)

I see the ability to have blown windows and the like as a big part of my low profile filming style

I have seen lots of dodgy highlights in other users films and wonder if they have been cranking the other way in search of wide DR (a reasonable thing to do)

I dont really want wide DR at the cost of tonal artifacting

This is CineTone 2 BTW

Ill seek out your settings unless you fancy posting them again

S
 
I appreciate your posts morgan. Let me ask, with your Super Knee, have you modified the range (Low, Middle, High) or the slope? If so, what variations, if any, are you seeing? If you haven't, what effect do you think it might have?
 
105 + 5 slope blows the highlights quicker than 105-5, (and would have a steeper curve and less artifacts in my theory)

Franky Im a little lost now beyond being convinced that the 85 area knees PP are creating plastic

NYVS post in the other thread is worth a read, he is a t 105/0 I think

But he has dialled up the color, while I have dialled all colours down to -3

im not sure I know what low/med/high you are refering too

I dont really have the toolset to do close analysis (or time)

S
 
I think its about trying to tune the setting to the native of the chip (105-0?)

Its obvious that the camera comes with setting that are non native being tuned towards DR by default (and creating artifcats)

BTW - I think the camera is a real step up from my 7 or EX1 - just trying to get the best

S
 
morgan_moore said:
105 + 5 slope blows the highlights quicker than 105-5, (and would have a steeper curve and less artifacts in my theory)

Franky Im a little lost now beyond being convinced that the 85 area knees PP are creating plastic

NYVS post in the other thread is worth a read, he is a t 105/0 I think

But he has dialled up the color, while I have dialled all colours down to -3

im not sure I know what low/med/high you are refering too

I dont really have the toolset to do close analysis (or time)

S
Click to expand...

Sorry, I got confused. The High, Medium and Low settings are for the black gamma settings. The auto knee setting has a sensitivity switch that is only High or Low. The auto knee also sets the slope automatically, which I am going to avoid.
 
Cintetone 2, Knee 105/0 colours -3

Did my first interview today.. pleased

(£49 nikon series e 35 f2.5 at 4)

Recompression by DVXuser seems to ad a little color moire that is not in the original -forehead)

interview.jpg

S
 
Last edited:
morgan_moore said:
Cintetone 2, Knee 105/0 colours -3

Did my first interview today.. pleased

(£49 nikon series e 35 f2.5 at 4)

Recompression by DVXuser seems to ad a little color moire that is not in the original -forehead)

View attachment 36374

S
Click to expand...

Looks good. What are you doing with your black levels? I love the Nikon primes BTW, I have a set including an E series 100mm F2.8. I think the E series lenses are highly underrated.
 
You must log in or register to reply here.
Back
Top