Please let us turn off Negafix!

[Russell]

Hello; I have been giving Silverfast a serious try and have concluded that I have more control over the tonal range and values of the image using Epson Scan. This is unfortunate as Silverfast has many other desirable features, not the least of which being a nice big accurate histogram. To me, Negafix is no more than a barrier to correcting the image. It often clips the upper end of the histogram, and distorts the tonal curves by its very presence; the latter cannot really be corrected with the tools available. I have been doing a lot of experimenting with scanning negatives as positives then converting them in Photoshop; I get better results this way, I think largely because it bypasses Negafix, and I can also apply the scanner profile I made with Monaco EZ Color which is an improvement over the canned Epson and Silverfast profiles.

Please add the option to turn off Negafix and simply use the raw histogram clear across the scanner's range, the same way that positives are scanned. It would make Silverfast a much more versatile tool.

Thank you very much,

--Russell

[LSI_Noack]

Dear Russell

thank you for your interest in LaserSoft Imaging's software products.

In the eye of many SilverFast users, especially Negafix is one of the strengths of SilverFast, so perhaps what you observed had been a bug, not a regular behaviour. In order of to have us that case examined closely, you might want to <a href="https://www.silverfast.com/problemreport/en.html?topic=Usage">open a support request</a>.

The feature you want is already implemented in SilverFast:
In a demo version of the Ai Studio, you'd want to disable to "Auto" orange mask removal: Expand the Negafix dialogue by clicking on the "Expert mode" icon, the de-check the box before the "Auto" button.
In a demo of a SilverFast SE Plus version, you would have this option available directly on the Negafix main dialogue window, et voila.

Best regards
Sonny Noack
- Manager Technical Support, LaserSoft Imaging AG -

[Russell]

Hello, and thank you for your reply. I should mention that I have already spoken to customer support and received helpful advice on understanding the capabilities of the expert dialog. And I still want to disable Negafix. This seems like a simple request to me, and it has been asked before in the forums. The "many" who want to go on using it are welcome to do so.

Disabling "auto" color cast removal is only part of the problem; the other is doing away with the Negafix film-specific color correction profiles, which is currently impossible while scanning as a negative.

I should also mention that I am using the full version of Silverfast Ai, an Epson 4870 scanner, and Windows XP.

--Russell

[LSI_Noack]

Dear Russell

to deactivate "auto" in the Negafix tool is not deactivating colour cast removal. This would be done as usually in the histogramme tool, and still can be done additionally to the "auto" feature in the Negafix.

What you want (to deactivate Negafix profile, but still convert) can be done by choosing to not set the "auto" option in that window and use the "Other"-"Other"-"Standard" Negafix profile.

Kind regards
Sonny Noack

[Russell]

Hello, and thank you again for the reply.

I have tried to illustrate what I am talking about here.

--Russell

[mathsartist]

is the conclusion here that unless you use a film that perfectly fits one of the predifined prf profiles, your pictures are not going to accurately depict the colours that exposed the film?

my scans are way off... I think this is a Negaproblem not a negafix.... considering selling my scanner as a solution.

[LSI_Morales]

Dear Rusell
Dear Mathsartist
Dear SilverFast users

NegaFix is a tool created with the goal of offering users "more control over the tonal range and values of the image" when scannig negatives.
Every single profile included there was created using a special targets used to calibrate printers in professional labs, those targets and calculation tables contain a very precise measurement of the density for every film type.

I have taken a look at Rusell description of the "problem", and found that there are many points where Rusell is not using the NegaFix features appropriately.

In the first place, he is using the Image automatic included in both, NegaFix dialog and the main setting window in SilverFast. He argued that he activated and then deactivated the "Auto" feature for limiting the expansion of the Histogram in every channel, then he claim to have moved the limits to the right. He also shows us the histogram he used when scanning the film with the possitive.

However, Rusell did not move the limits to the left side of the expansion of the histogram included in the NegaFix dialog, as a consequence, he left the gray point in a darker place within the histogram. Hence the high contrast in the image.

Its important to know that the histogram in the NegaFix window is inverted as the one present in the main window (because it is a positivation of the original scan which is negative).

In such cases, you can actually reset the auto tolerance by presing the "reset" button next to it, you can then place the limits of the histogram as desired as you would in the main settings window.

Another important thing to acknowledge, is to deactivate the color cast removal, within the options dialog, under the "Auto" tab. Another tool that should be deactivated is the "Image-Automatic" so the contrast limits and gray point will not be set by the program.

We have a very complete document about NegaFix, and the possibilities to use its extended features (which are only available in SilverFast Ai), please check the following document:

http://www.silverfast.com/download/docs ... Fix-en.pdf

You can also find some isntructive videos at:

http://www.silverfast.com/download/movi ... -08-09.mov
http://www.silverfast.com/download/movi ... -05-13.mov
http://www.silverfast.com/download/movi ... -08-12.mov
http://www.silverfast.com/download/movi ... -11-28.mov

Least but not last, if you want to use the maximum dynamic range of your film negatives, you should make sure to scan your film in 48 bits color and not 24 bits (as Rusell did) which will again limit the quality of your image.

If you definietely do not want to use NegaFix but still want to make the most of your negative film, you still can scan in 48 bits HDR and save as a TIFF file, your negatives will be scanned to the most of your scanner capabilities and the resulting files will be untouched, no effects or corrections will be applied to them. Those files can then later be edited in your favorite suite.

As a conclussion we could not only say that NegaFix can be manipulated as desired by users (of course it requires users to instruct about its capabilities and experiment with its posilities), but essentially it can be completely turned off (as desired by some users and as the main topic for this forum thread!).

Greetings

[Russell]

Hello, and thank you for the reply. But I can still find no way to move either side of the histogram limits in NegaFix to show all the available detail in the extremes, especially the highlights, of the image. And you should know that processing the HDR file in an application such as Photoshop will produce mediocre results at best; ordinary editing tools are simply not designed to handle information conveyed in the form of high-bit images.

However, I have found another solution to the problem which gives even more control over the results, and have published it in the place of the original illustration at http://www.russellcottrell.com/photo/SilverFast/.

Thank you again,

--Russell

[LSI_Morales]

Dear Russel,

Thanks for your contribution, I have checked your explanation, it seems to me as though you are mixing up NegaFix with what you actually want to obtain (which is pretty valid), however you can not expect NegaFix to automatically make the compression you want to make.
The option you offered is pretty valid, you could also make an HDR scan in SilverFast (which gives you an unmodified TIFF RAW file) and open it in SilverFast HDR to export the three pictures you will use later in photoshop.
When scanning in 48 bits HDR you will obtain the complete latitude of your negative as you describe in your site, then in HDR you can create as many pictures as you want out of this RAW file, the advantage here is that you will only need to make one scan instead of three of them saving you a lot of time.

Cheers

[Jack Montgomery]

I am having the opposite problem. I am running SilverFast AI studio with an epson v750. I am using the Negafix option but when the Tiff is created it is still the negative image. I can invert in photoshop but I suspect the result would be better if that was happening in the SilverFast environment. I am scanning TMAX 400 BW film at 16 bit hdr grayscale.

Any suggestions?

Thank you.

Jack Montgomery

[LSI_Morales]

Dear Jack,

The thing is that you are creating unmodified raw files, so inversion is not taking place. This is normal when you are using any HDR scanning mode.

Remember that your computer monitor is only an 8 bit device whereas your resulting HDR files are 16 bits. It means they contain much more information than your monitor is capable of showing. You can use that extra information to correct the resulting file.

Cheers