Slide film thickness (after exposure) and Scanning

[erotavlas]

Hi I was wondering if there are differences in the thickness of the slide films out there today. I tried a roll of Fuji Velvia 100 recently and then scanned it with Epson Photo scanner and I had terrible results (the light just couldn't penetrate well through darker areas)

But I remember using a roll of Kodak Ektachrome 200 many years back and it scanned so much better than the Velvia

So I was wondering if there is in fact a difference in the thickness of slide films that would affect the outcome of a scan or is it only dependant on the exposure.

If there is a difference can anyone recommend a slide film that exists today that would be best. (strictly considering the ability of the scanner light to penetrate the film)

Thanks for any advice

 

[joealcantar]

I would just let the lab that processed the film do the scanning that way you know if it is the film or the scanner you are using.
-
Shoot well, Joe

 

[erotavlas]

I would just let the lab that processed the film do the scanning that way you know if it is the film or the scanner you are using.
-
Shoot well, Joe

Even if I did that and I got a better result for a particular film it would only tell me that the scanner I used wasn't good enough to scan through the film I already know that my scanner has limits and I think it has reached it with the Fuji Velvia film I was using.

What I really want to know is if there is a particular film out there that scans better than others when using comsumer level scanners .(not a drum scanner)

 

[Pgeobc]

Well, E-6 processing is well standardized, so the chances that the lab goofed are less than if you have a problem.

If the slides are too dense, then they may be underexposed. You have to correct that with exposure changes.

If there is a problem with the scanner, try changing the settings on the scanner. Mine has that option.

The film base is not at fault, as slide film bases are nearly clear and are black where not exposed.

 

[erotavlas]

Well, E-6 processing is well standardized, so the chances that the lab goofed are less than if you have a problem.

If the slides are too dense, then they may be underexposed. You have to correct that with exposure changes.

If there is a problem with the scanner, try changing the settings on the scanner. Mine has that option.

The film base is not at fault, as slide film bases are nearly clear and are black where not exposed.

good advice, thanks. I guess since my scanner seems to work fine (negatives scan well) I will try to slightly over expose the film instead. Probably my metering was off when I shot the Velvia and I underexposed the film which is why they appear dark to begin with.

 

[compur]

Slide film is the most difficult to shoot correctly. It has very little exposure latitude and
the slower slide films, like Velvia 50, often have high contrast which makes achieving
shadow detail more difficult -- which then makes scanning more problematic. It can be done
and beautiful results can be achieved with it but it takes precise exposure and appropriate
lighting techniques.

Most any color print film is usually easier to deal with as print films normally have a much
wider exposure latitude and lower contrast, making them more forgiving of exposure errors
and less-than-perfect lighting.

 

[Helen B]

The technical name of the property you are asking about is DMax - maximum optical density. It varies from film to film, as you say. Velvia 100 has a relatively high DMax compared to other films. Even 'properly' exposed slides can have areas of the image at the film's maximum density - it's not necessarily a sign of underexposure, especially if you want to use the full density range of the film (DRange).

The actual DMax the film achieves depends on the processing. This is getting more and more inconsistent because many labs seem to be struggling to keep their E-6 lines up to standard. Lab problems are most likely to result in low density rather than high density, however. (We still shoot quite a lot of large format reversal film for publication and we are seeing more processing problems than ever.)

Most reversal film has an ideal DMax when processed properly of between 3.0 and around 3.7 (it's a logarithmic scale) depending on which of the RGB channels you measure and how you measure them. Velvia 100 has a DMax of 3.8 (green). Ektachrome E200 has a DMax slightly lower - around 3.7 (blue). Ektachrome E100G is somewhere between those two (blue).

These densities are near the practical limit for consumer scanners, so it is most important that you are setting up the black point correctly - I assume that you are doing that manually. The histogram will tell you if you have a big problem with DMax.

If you overexpose you are reducing the film's DRange. Instead of doing that, if you have a problem getting what you want with slide film, switch to neg film as others have suggested.

Best,
Helen