Best way to calibrate 2 DVX's at DVinfo.net

Peter Jefferson · August 14th, 2005, 12:52 AM

Now ive got two of these units, ones the Original release, the other being the 100a.. now if i had both units being the same model, this issue woudlnt arise, however it has.. so heres the big Q...

Now the 100a has different scene file settings to the Original, with afew extra cinegamma settings, as well as detail coring option...
one thing i notice, is that despite my efforts (ive been with these cams for almost 3yrs now) i still cant get an accurate match in cam.. i still have to slightly tweak one of them in post so i can match the cameras...

I dont want to do this as its a waste of time, and to most poeple, the differences arent noticable, but to me differences are enough to give me a headache in post

anyways, one thing ive noticed between the 2, is that the 100a has...
-Slightly more noise that the 100 when gain is at 12db
- Slightly less sensitivity (maybe half a stop depending on the situation)
-Slightly sharper image (I dunno if this is the detail coring, however i set my coring on the A to +4) the rest of the detail settings are are -1 to stop the infamous blue bleeding (in Pal its not as bad as NTSC)
-White balance is slightly greener on the A, but its also a lil cooler depending on the precise lighting situation. Normally i notice it is slightly cooler above anything else.. the green is not a problem, i can get rid of that by readjsuting.
-Gamma set to CineV is richer in contrast, and smoother on blowouts... pity the 100 doesnt have this..
-even with colour phasing set to -4, purples and orange colours still come out with a predominately blue or red tint on the 100a, whereas the 100 doesnt have this.. is far more accurate

so now my predicament is to have a setting which allows me to have the 2 cameras virtually identical, but for the life of me, i cant get it happening right.. now ive shot at least 25jobs with this issue, and white balancing manually is alwyas slightly off.. ive had to literally put it in auto mode and have both cams pointing to the same object.. once theyre look ok, i then lock the WB by assigning the WB lock to a user button.

So does anyone know of a good way to get a good match??
This jsut doesnt work if i have 2 cams in 2 different areas and we have to fly with the situation.. auto just cant keep up and i dont like the idea of automatic WB phasing
I dont really want to dumb down the 100a either...

any assistance appreciated

Stephanie Wilson · August 24th, 2005, 12:05 AM

Peter,

You may have to dumb down the 100A to match the 100.

Set the 100A gain at 9db instead of 12db

Your coring setting at +4 should indeed decrease video noise

Re the 100A manual: Cine-LikeV, this uses the gamma curve for finishing the images into movie-like images where priority is given to contrast. In addition:In order to make full use of the CINE-LIKE gamma characteristics, it is recommended THAT THE LENS IRIS BE SET LOWER (BY APPROX. 1/2) THAN THE REGULAR VIDEO LEVEL.

Also check whether you have the black level setup level of the 100A at 7.5% !!!

Lastly, and at the very least, set up both cameras using correct color bars.

I'm sure you will receive many more educated answers via this forum very soon.

Steph

Peter Jefferson · August 26th, 2005, 08:17 AM

i thought as much..

ive used these cameras since theyve been out and for the life of me i still cant find fault with them but this had me so agro i was losing the plot.

with regard to gain, sometimes i have no choise but to use 12db.. i try not to.. but 12db on the original is clean , owever on the 100a, it is VERY noisy.. scary infact

hmm.. just recalling your quote re the manual.. it seems they want a slightly underexposed shot..
I did this naturaly as it DID in fact look the part (as with DoF which IMO is as important to generate that film look)
This is ideal for most situations with constant light, however in a nightclub, theatre or dance party (or wedding for that matter) ive needed to switch the Gamma to Normal or High to bring out that exposure.
When both cams share the same gamma curve, i dont have an issue apart from colour balancing manualy and noise in the shot.. but i guess when ur working with 2 different cameras, it wont ever be perfect...

oh well.. more work in post for me then..

August 14th, 2005, 12:52 AM	#1
Peter Jefferson Inner Circle Join Date: Apr 2003 Location: Aus Posts: 3,884	Best way to calibrate 2 DVX's Now ive got two of these units, ones the Original release, the other being the 100a.. now if i had both units being the same model, this issue woudlnt arise, however it has.. so heres the big Q... Now the 100a has different scene file settings to the Original, with afew extra cinegamma settings, as well as detail coring option... one thing i notice, is that despite my efforts (ive been with these cams for almost 3yrs now) i still cant get an accurate match in cam.. i still have to slightly tweak one of them in post so i can match the cameras... I dont want to do this as its a waste of time, and to most poeple, the differences arent noticable, but to me differences are enough to give me a headache in post anyways, one thing ive noticed between the 2, is that the 100a has... -Slightly more noise that the 100 when gain is at 12db - Slightly less sensitivity (maybe half a stop depending on the situation) -Slightly sharper image (I dunno if this is the detail coring, however i set my coring on the A to +4) the rest of the detail settings are are -1 to stop the infamous blue bleeding (in Pal its not as bad as NTSC) -White balance is slightly greener on the A, but its also a lil cooler depending on the precise lighting situation. Normally i notice it is slightly cooler above anything else.. the green is not a problem, i can get rid of that by readjsuting. -Gamma set to CineV is richer in contrast, and smoother on blowouts... pity the 100 doesnt have this.. -even with colour phasing set to -4, purples and orange colours still come out with a predominately blue or red tint on the 100a, whereas the 100 doesnt have this.. is far more accurate so now my predicament is to have a setting which allows me to have the 2 cameras virtually identical, but for the life of me, i cant get it happening right.. now ive shot at least 25jobs with this issue, and white balancing manually is alwyas slightly off.. ive had to literally put it in auto mode and have both cams pointing to the same object.. once theyre look ok, i then lock the WB by assigning the WB lock to a user button. So does anyone know of a good way to get a good match?? This jsut doesnt work if i have 2 cams in 2 different areas and we have to fly with the situation.. auto just cant keep up and i dont like the idea of automatic WB phasing I dont really want to dumb down the 100a either... any assistance appreciated

August 24th, 2005, 12:05 AM	#2
Stephanie Wilson Major Player Join Date: May 2005 Location: Sherman Oaks CA Posts: 255	Peter, You may have to dumb down the 100A to match the 100. Set the 100A gain at 9db instead of 12db Your coring setting at +4 should indeed decrease video noise Re the 100A manual: Cine-LikeV, this uses the gamma curve for finishing the images into movie-like images where priority is given to contrast. In addition:In order to make full use of the CINE-LIKE gamma characteristics, it is recommended THAT THE LENS IRIS BE SET LOWER (BY APPROX. 1/2) THAN THE REGULAR VIDEO LEVEL. Also check whether you have the black level setup level of the 100A at 7.5% !!! Lastly, and at the very least, set up both cameras using correct color bars. I'm sure you will receive many more educated answers via this forum very soon. Steph

August 26th, 2005, 08:17 AM	#3
Peter Jefferson Inner Circle Join Date: Apr 2003 Location: Aus Posts: 3,884	i thought as much.. ive used these cameras since theyve been out and for the life of me i still cant find fault with them but this had me so agro i was losing the plot. with regard to gain, sometimes i have no choise but to use 12db.. i try not to.. but 12db on the original is clean , owever on the 100a, it is VERY noisy.. scary infact hmm.. just recalling your quote re the manual.. it seems they want a slightly underexposed shot.. I did this naturaly as it DID in fact look the part (as with DoF which IMO is as important to generate that film look) This is ideal for most situations with constant light, however in a nightclub, theatre or dance party (or wedding for that matter) ive needed to switch the Gamma to Normal or High to bring out that exposure. When both cams share the same gamma curve, i dont have an issue apart from colour balancing manualy and noise in the shot.. but i guess when ur working with 2 different cameras, it wont ever be perfect... oh well.. more work in post for me then..