[plugin] Film Simulator "Nostalgia" (nee Andrea) Released

[n00b]

Yes, please share your Nostalgia!

Got it (free), like it, must buy... thanks.
http://www.flickr.com/photos/janus_sand ... /lightbox/

[n00b]

I know its kind of bad taste, but sunset at Zanzibar never looked that..colourful..
Having fun, learning at my playground http://www.flickr.com/photos/janus_sand ... 823510041/


Lightbox: http://www.flickr.com/photos/janus_sand ... /lightbox/

[seanmpuckett]

Just a note about a maintenance release of Nostalgia version 1.0.6. The only change is an upgrade to the registration code to handle unicode directory names, brought to my attention by a user in Russia. If you haven't had a problem registering Nostalgia, you don't need this update; nothing else has changed.

[Zarastro]

Hi Sean,

I was getting strange color casts in the UI when using Nostalgia to convert to B&W in ASPro. After studying the image, I've finally found that when converting to B&W using Nostalgia it takes the color channels of the picture into account after converting the image to black and white. Thus, if you have changed the color balance of the picture through the histogram tool, this change in color balance is being propagated to Nostalgia after the gray scale conversion, and thus images acquire a color cast.

See this example (click on the image for big version):



If you look the histogram of the picture, you'll see that it's not a histogram for a B&W picture - there are vestiges of blue and magenta which are responsible for the visible violet color cast in the picture. I've then reset the curves and the picture looks "real" B&W again, with the corresponding correct histogram:



That is, when you deactivate "colour" option on Nostalgia, it continues to operate with the image in a RGB color space instead of converting the image to gray scale. Bug or feature?

[afx]

That is, when you deactivate "colour" option on Nostalgia, it continues to operate with the image in a RGB color space instead of converting the image to gray scale. Bug or feature?

Feature.

AS operates always in RGB, so the result of Nostalgia is always RGB.

Nostalgia sits before curves in the pipeline, so all curve adjustments happen after Nostalgia worked on the image.
Check the AfterShotPro.log file for the exact position in the pipeline.

cheers
afx

[ferdinand-paris]

I haven't tried it, but I think you'll find this behaviour with every B&W converter for ASP, with one exception. They all (bar one) execute before curves, and as B&W is achieved by setting R=G=B (or L=0 in the brief LAB stage before converting back to RGB), then changing one colour channel more than another after conversion will give you a colour cast.

The one exception is Silicon Bonk. As I understand it, SB was intentionally placed after curves by its author spoilerhead precisely to do what you want to do. However it comes with a catch. The histogram is calculated at the curves stage, so you can't see the impact of SB on the histogram. Use SB and you will see the image change but not the histogram. Which is why most other converters and indeed most other plugins run before curves.

Plugins are a strength of B5 & ASP, but they have at least one Achilles' heel. Which is that sometimes you need to change the order of some plugins, but you can't. Some authors provide options for varying where in the image processing pipe you place them, but this practice isn't common. I wish it was more common, but it does entail some work.

F_P

[seanmpuckett]

Zarastro: I'm not sure you got the answer you're looking for, though since I can't see the settings you chose for Nostalgia I can't confirm what is happening for you.

However, If you're using a B&W negative film in B&W mode but you are printing on colour paper, you'll get a colour cast -- yes, even if you've selected B&W processing. That's because the colour papers in Nostalgia all have a colour cast.

The B&W condensing happens before the virtual camera in the simulator, according to the settings of the filter sliders and in combination with the spectral sensitivity of the chosen film. It only happens once, so any colour casts that creep in along the simulation chain stay there.

There's one exception: when shooting on colour negative film with a tinted base AND printing the result, I automatically add the appropriate filter pack in the enlarger to counter the tinted base. Fun effect: If you shoot on colour negative film but turn off printing, you can see the tinted base in the displayed negative image.

Hope this clears things up.

[ferdinand-paris]

He did say:

... Thus, if you have changed the color balance of the picture through the histogram tool, this change in color balance is being propagated to Nostalgia after the gray scale conversion, and thus images acquire a color cast.

I assume he means the curves tool, and on my system Nostalgia loads before curves. I take this to mean that he's trying to use the curves tool to vary the RGB mix before conversion, but of course all he's doing is giving it a post-conversion colour cast.

F_P

[seanmpuckett]

F_P: ahh, that makes sense. So, my explanation didn't address his issue directly. Thanks!

[andrewh]

Sorry for asking this question here but did 1.0.1 ever appear and if not is Nostalgia fine without it? When I check for updates I get told that my 1.0.0.39 is the latest version and I cannot find any patch or update on the Corel site.

Thanks
Andrew from Addis

[claudermilk]

ASP 1.0.0.39 is the latest; any mention of other versions is probably closed betas. While I haven't used it heavily (yet), I have had no issues with Nostalgia.

[Zarastro]

Feature.

AS operates always in RGB, so the result of Nostalgia is always RGB.

Nostalgia sits before curves in the pipeline, so all curve adjustments happen after Nostalgia worked on the image.

Thanks. Followed the instructions and it worked as a charm. However, this is different from B5, right? I've converted an image using Andrea and tried to change the color balance in the Color Tab and the image remained B/W - no color casts were visible. It's just like applying different color filters to achieve different levels of B&W.

@Sean, thanks for Nostalgia. It's really great, furthermore with all of those films and papers in the registered version!

[afx]

However, this is different from B5, right?

No idea I must admit.
If you compare the logfiles of both, you can see the pipeline...

cheers
afx

[seanmpuckett]

Zarastro, if you'd like to apply filters to Nostalgia images, it's best to use the filter sliders in the Nostalgia plug-in when possible as they're at the correct place in the simulation for the behaviour of "real" filters. They permit control over +/- 8 stops of variation without the risk of signal-to-noise or clipping losses of filtering in ordinary 16 bit linear space.

You can use Nuance, which runs before Nostalgia, to adjust filtration also.

[ferdinand-paris]

However, this is different from B5, right? I've converted an image using Andrea and tried to change the color balance in the Color Tab and the image remained B/W - no color casts were visible.

In your previous post you mentioned the histogram, which I took to be curves. Curves is after Andrea in B5 and so can't preserve B&W. Colour balance is before and so B&W is preserved. As AFX said, the log will tell you the plugin order and so what is before Andrea/Nostalgia and what is after and so what you can use to manipulate the B&W mix and what you can't.

F_P