Does Silverfast control the lamp brightness ?

[norris_watkins]

I thought the Epson software that came with the scanner is capable of controlling the brightness of the lamp ( they call it 'Exposure' )
Does Silverfast 8.0 also do the same ?
1. What happesn when I move the Shadow and Highlight sliders under Histogram in Silverfast ? ( It is processed by the software. Or does it result in hardware lamp brightness ? )

2. Silverfast has to be controlling the lamp brightness during Multiple Exposure right ?

[LSI_Morales]

Hi there

I thought the Epson software that came with the scanner is capable of controlling the brightness of the lamp ( they call it 'Exposure' )
Does Silverfast 8.0 also do the same ?

I do not know how the Epson software internally works, but I do not believe the feature mentioned controls the lamp brightness. Perhaps it controls the exposure time (longer exposures = more light, shorter exposures = less light).

SilverFast has the Multi-Exposure feature which also controls the exposure time combining two different scans (with different exposures) to obtain the entire range of the scanner.

1. What happesn when I move the Shadow and Highlight sliders under Histogram in Silverfast ? ( It is processed by the software. Or does it result in hardware lamp brightness ? )

It is a software process based on the raw information from the scanner

2. Silverfast has to be controlling the lamp brightness during Multiple Exposure right ?

Wrong, SilverFast does not control the lamp brightness, it controls the exposure speed.

Kind regards

[norris_watkins]

Thanks a lot for clarifying it.
( I didnt think of time being a possible player in controlling exposure )

[LSI_Morales]

Hi Norris

( I didnt think of time being a possible player in controlling exposure )

Just like the shutter speed in your camera!

Cheers

[norris_watkins]

Sorry I came back to visit your answer in more details.

So The way I understand it, during Multi Exposure, silverfast makes two passes.
A slow pass ( high exposure ) to capture the shadows
And a fast pass ( low exposure ) to capture the highlights

Then it combines the shadow areas from the high exposure pass with the highlights areas from teh low exposure pass, and generates an image that will have details on both shadows and highlights ?
Is that correct ?
If true, this will be somewhat akin to HDR in digital photography ( I know Silverfast uses teh term 'HDR' to really mean 'RAW' )

By the way, why does not silverfast allow you to do ME on Reflective photos ? ( Maybe because prints have low dynamic ranges ? )

[LSI_Morales]

Hi Norris

So The way I understand it, during Multi Exposure, silverfast makes two passes.
A slow pass ( high exposure ) to capture the shadows
And a fast pass ( low exposure ) to capture the highlights
Then it combines the shadow areas from the high exposure pass with the highlights areas from teh low exposure pass, and generates an image that will have details on both shadows and highlights ?
Is that correct ?

This is partially correct.
Multi-Exposure makes two scans, one at a normal speed scanning the image as is from a normal scan and a second pass at a slower speed, overexposing the entire image.
These two resulting images are combined, a special algorithm takes care of leaving the highlights intact and revealing details and more information included in the dark areas of the picture, not visible with a normal scan.

By the way, why does not silverfast allow you to do ME on Reflective photos ? ( Maybe because prints have low dynamic ranges ? )

Kind regards
Multi-Exposure is a hardware dependent feature, reflective more does not offer control over scan speed.