Epson V750 custom holder for 13x18 negatives: scan remains black

[iconoclastica]

Just for a test (once it works, precision manufacturing will follow) I hacked a custom film holder for 13x18 B&W negatives. It is made of matte board and all it does is lifting the negative a few mm from the glass.
Only I can not find any scan setting that scans the image on the negative. All I get is an entirely black scan, only the propietary program "Epson scan" also notifies me after several minutes trying to make a prescan that no image could be found. I have tried VueScan, Silverfast en the Epson utility. When I try the same with the MF holder and the 13x18 draped over it (don't mind a few scratches here), I can clearly discern the image on the negative.

Therefore it seems to be the actual holder that cannot so easily be copied by a simple placeholder. I can see some braille-like code pinholes in the various film holders that I assume pass information to the scanner about which fim holder is being used. But I had the impression that some of you have been succesful with scanning up to 5x7, isnt that so? What settings do you use?

[Randy]

When I scan 5X7 negs I lay the 8X10 scanning mask (for 8X10 negs) down with the 5X7 neg placed inside. Do you have it set scanning with film holder or film area guide. I believe you need to set it at film area guide, though I am not sure how much difference that makes. Does your custom film holder cover the entire glass scanning area? If so, that could be the problem as there is a notched out area on all the holders and area guides that runs the length across the top. If that area is covered it could fool the scanner.

[djdister]

I use a custom 5x7 neg holder made out of mat board on my v750. I place it inside the Film Area Guide and tell Epson Scan that I'm using the film area guide and not the film holder. The 5x7 scans work just fine this way.

[Jeff Dexheimer]

There has to be about an inch gap between the starting edge of the glass and the holder. On an epson or aftermarket neg carrier this is solved with a u shaped spacer. The outer edges of the u tell the scanner the width of the scan. If you dint have the gap, the scanner will make everything black.

[iconoclastica]

Thanks, Jeff, that is what causes the issue. When I leave an inch or so at the top of the bed, the scan comes out as expected. I suppose that is what Ernst Dinkla calls the "calibration window", a term that I never quite understood before.

BTW, I am not using the 8x10 guide for my (second hand) scanner didn't include it, but also because I understand that using the film holders makes the scanner switch to a longer focus lens with a better resolution potential.

There has to be about an inch gap between the starting edge of the glass and the holder. On an epson or aftermarket neg carrier this is solved with a u shaped spacer. The outer edges of the u tell the scanner the width of the scan. If you dint have the gap, the scanner will make everything black.

[kleinbatavia]

Well, I've tried hacking pieces of board and scanning in the 8x10 guide and a bunch of other things. Some work, others do not. I had hoped to get a better scanning holder, but as they will not even reply to repeated requests for information, I've decided they can get lost. Instead, I now have a new plan B. I've ordered a spare 4x5 film holder. Once it gets here, I will get my dremel fired up and hack the middle section out of the holder. This means cutting the bottom support as well as the to clamps. I'm sure that this will reduce rigidity by a bit and it will possibly also cause the negative to be slightly less flat. However, it will still be held on 3 sides and if needed, I cal always glue the cut bit at the bottom to support the 4 sides. This way, I can scan with the high-res lens and by setting the "crop area" to manual, I should be able to just scan a single 5x7 at high res. Anyway, if anyone is interested, I'll post an update once it's done. Might be a while though, the holder is coming to the EU from the US and will get stuck in customs because it exceeds the maximum VAT free amount by $3,95.

[asf]

Any results?

[kleinbatavia]

Ah yes, my response was long overdue. I never did hack the second 4x5 holder I got... However, I have another solution. It's using magnetic sheets to achieve the right thickness (distance from the glass) and cutting the calibration window and desired frame size out. Work very well for 5x7 and 4x10 so far...