Photoshop curves for film ? at DVinfo.net

Gints Klimanis · January 27th, 2004, 06:53 PM

Hi,

I'm trying to process some video frame grabs with Photoshop.
I'd like to apply the film s-curves by selecting from a number of
Presets. The .MAP files on this site look right, but with X and Y axes swapped.

Check the film correction curves here :

http://www.aim-dtp.net/aim/techniques/photograph/

Does anyone know how to swap the axes or have any other curves or maps files? If not, I'll just tweak the dozen or so files
and make them available.

Thanks !

Frank Ladner · January 27th, 2004, 09:35 PM

Gints: I'm not sure if this is it, but here goes...

Looking at the Curves dialog box in Photoshop, you should have the two greyscale bars - a vertical one, located to the left, and a horizontal one, at the bottom of the curve lines.

On the horizontal one, there should be a little white button looking thing in the middle, with two arrows pointing left and right. You should be able to click the two arrows to swap the axes.

Hope that helps!

,Frank

Rob Lohman · January 28th, 2004, 03:55 AM

A lot of tweaking like that can be done in an NLE which has
good curve tools (like Vegas and Avid). I'm not sure what (good)
tools Premiere has.

Gints Klimanis · January 28th, 2004, 02:45 PM

Frank,

Thank you for the suggestion. I tried the little arrows, but they also include an inversion. So, the "little arrow" process seems to mirror (swap -N with + N) both x and y around an origin in the middle of the grid, which isn't quite the same as swapping X and Y with the origin at the lower left of the grid.

Thanks. I just used the polynomial mode to approximate a couple of curves, but I was hoping to tweak the real data.

Jami Jokinen · January 29th, 2004, 12:44 AM

<<<-- Originally posted by Rob Lohman : I'm not sure what (good)
tools Premiere has. -->>>

Almost nothing by itself, but combined with a Canopus card it has beautifully working YUV-curves along with other great tools.

January 27th, 2004, 06:53 PM	#1
Gints Klimanis Inner Circle Join Date: Jun 2003 Location: San Jose, CA Posts: 2,222	Photoshop curves for film ? Hi, I'm trying to process some video frame grabs with Photoshop. I'd like to apply the film s-curves by selecting from a number of Presets. The .MAP files on this site look right, but with X and Y axes swapped. Check the film correction curves here : http://www.aim-dtp.net/aim/techniques/photograph/ Does anyone know how to swap the axes or have any other curves or maps files? If not, I'll just tweak the dozen or so files and make them available. Thanks !

January 28th, 2004, 03:55 AM	#3
Rob Lohman RED Code Chef Join Date: Oct 2001 Location: Holland Posts: 12,514	A lot of tweaking like that can be done in an NLE which has good curve tools (like Vegas and Avid). I'm not sure what (good) tools Premiere has. __________________ Rob Lohman, visuar@iname.com DV Info Wrangler & RED Code Chef Join the DV Challenge \| Lady X Search DVinfo.net for quick answers \| Buy from the best: DVinfo.net sponsors

January 27th, 2004, 09:35 PM	#2
Frank Ladner Major Player Join Date: Aug 2003 Location: Poplarville, MS Posts: 453	Gints: I'm not sure if this is it, but here goes... Looking at the Curves dialog box in Photoshop, you should have the two greyscale bars - a vertical one, located to the left, and a horizontal one, at the bottom of the curve lines. On the horizontal one, there should be a little white button looking thing in the middle, with two arrows pointing left and right. You should be able to click the two arrows to swap the axes. Hope that helps! ,Frank

January 28th, 2004, 02:45 PM	#4
Gints Klimanis Inner Circle Join Date: Jun 2003 Location: San Jose, CA Posts: 2,222	Frank, Thank you for the suggestion. I tried the little arrows, but they also include an inversion. So, the "little arrow" process seems to mirror (swap -N with + N) both x and y around an origin in the middle of the grid, which isn't quite the same as swapping X and Y with the origin at the lower left of the grid. Thanks. I just used the polynomial mode to approximate a couple of curves, but I was hoping to tweak the real data.

January 29th, 2004, 12:44 AM	#5
Jami Jokinen Regular Crew Join Date: May 2002 Location: Finland Posts: 103	<<<-- Originally posted by Rob Lohman : I'm not sure what (good) tools Premiere has. -->>> Almost nothing by itself, but combined with a Canopus card it has beautifully working YUV-curves along with other great tools.