Can't find the scanner thread.

soupdragon

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Tony
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Question.
Can anyone tell me how far above the scanner glass is the film when using the Epson V850 pro 4X5 film holders?

The reason I ask this is, that the Epson 8X10 film guide requires the negative/transparency to be in contact with the scanner glass. This must surely be lower than the optimal plane of focus for the scanner lens.

I'm confused.
 
OK, answering my own question.
The nominal height for all Epson film holders is 3mm.

So, the next question is, can 3mm optically clear glass be purchased easily?
 
Or polycarbonate.
 
Question.
Can anyone tell me how far above the scanner glass is the film when using the Epson V850 pro 4X5 film holders?

The reason I ask this is, that the Epson 8X10 film guide requires the negative/transparency to be in contact with the scanner glass. This must surely be lower than the optimal plane of focus for the scanner lens.

I'm confused.

Doesn't the Epson 4 x 5 film holder 'hold' the film at the correct height?
 
Yes it does but. I omitted to say I'm trying to scan 8X10".
My Bad.
OK Tony, the Epson 850 adjusts its focus when scanning 10 x 8 film to be on the glass patten to prevent 'sag' in the negative; hence why Epson only provide te guide.
Place emulsion side up to help prevent Newton rings.

HTH

***edited to say emulsion side up***
 
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OK Tony, the Epson 850 adjusts its focus when scanning 10 x 8 film to be on the glass patten to prevent 'sag' in the negative; hence why Epson only provide te guide.
Place emulsion side down to help prevent Newton rings.

HTH
That I did not know.
I thought the V850 was fixed focus but swapped lenses depending on resolution.

Where are you getting this info from? I'd really like to read the full data sheet.
 
That I did not know.
I thought the V850 was fixed focus but swapped lenses depending on resolution.

Where are you getting this info from? I'd really like to read the full data sheet.
When using the 8 x 10 guide the scanner 'recognizes' the guide being used and switches lens to the lower resolution but on an 8 x 10 negative that is still a huuuuge file!
 
From the t'internet:

The 8x10 guide for the 850 doesn’t look like the negative holders. It’s a plastic stick, like a slender capital I, that you place along the hinge end of the glass bed. Its main function is to provide black and white level calibration for the scan. The space between the “serifs” is about 8 inches. I can send you pictures. Note that in 8x10 film mode the 850 focuses on the plane of the glass, not a few mm above it (where the other film holders focus)


I used to use the 850 for my scanning requirements; some time ago so memory is fading :oops: :$
 
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Page 30:

chrome-extension://efaidnbmnnnibpcajpcglclefindmkaj/https://files.support.epson.com/docid/cpd4/cpd41530.pdf

Page 90 for specs showing the lower resolution camera is used for 10 x 8 which focuses on the patten as if copying documents or film prints.
 
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This is not my work.
A chap over on the large format forums called Ian produced this.

1750940713182.png
 
This is not my work.
A chap over on the large format forums called Ian produced this.

View attachment 456510
This will give you the Correct answers:


N.B. It DOES NOT use the high resolution lens for 8x10 scanning!

Summary Table​

Scan ModePlacementFace OrientationLens UsedFocus PointOptical Resolution
ReflectiveOn platen glassFace downLower-res lens (fixed focus)Glass surface~2400 dpi
Transparency (holders)In film holder above glass (~2.5 mm height)Emulsion downHigh-res lens (adjustable)~2.5 mm above glass~4800 dpi
Transparency 8×10Directly on platen glassEmulsion downLower-res lens (fixed focus)Glass surface~2400 dpi
 
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This will give you the Correct answers:


N.B. It DOES NOT use the high resolution lens for 8x10 scanning!

Summary Table​

Scan ModePlacementFace OrientationLens UsedFocus PointOptical Resolution
ReflectiveOn platen glassFace downLower-res lens (fixed focus)Glass surface~2400 dpi
Transparency (holders)In film holder above glass (~2.5 mm height)Emulsion downHigh-res lens (adjustable)~2.5 mm above glass~4800 dpi
Transparency 8×10Directly on platen glassEmulsion downLower-res lens (fixed focus)Glass surface~2400 dpi
Do both Silverfast 9 and Epson Scan operate in the same manner?
My personal preference is for Silverfast,
 
Do both Silverfast 9 and Epson Scan operate in the same manner?
My personal preference is for Silverfast,
I don't get the issue TBH Tony? Have a read through the post I made, why would you want to scan a 10 x 8 transparency at higher resolution than 2400 which will give a huge file anyway (approx 480 magapixels!!!)?

In Silverfast set the resolution to 1200; the true optical limit for the Epson is circa 2400 anyway.
 
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