Will wet mounting fluid damage glass?

[Deliberate1]

Friends, I have an Eversmart Pro II. I have been told that Kami fluid applied directly to the glass can damage the coating. If so, are there alternatives to the Koday mounting station, which might not work with the Pro II, and would cost too much, anyway.
Thanks, David

[Peter De Smidt]

I have a Cezanne. I don't know if the following will be applicable, but it might help. My scanner came with a thick acrylic scanning bed with a very fine anti newton texture. It was marked up quite a bit, though. Since the bed was removable, I made an insert that goes where the bed goes out of MDF, and in the center of that sheet I machined out an opening for a piece of optical glass. I sealed the mdf with spray shellac and then multiple coats of krylon ultra flat black, and I made sure that the height of the glass was the appropriate height. I scan by fluid mounting the film on top of the optical glass, using Prazio mounting oil and mylar. It works well, and since the glass isn't coated, there's been no problems in that regard. Perhaps you could do something similar.

[Deliberate1]

Peter thanks for your reply. Since the glass on the Eversmart is removable as well, your solution would be a good one. Where did you get the glass for the insert? And I assume that your insert and the glass are at the exact level or height of the original glass so as to insure the proper focus? Thanks for the suggestion.

[Peter De Smidt]

Hi,

I used the optical glass tray from a Agfa T2500 scanner. There are lot's of other options, though. If you're scaning bw, a clean piece of regular float glass should be ok. With color, the green tinge might be a problem. You used to be able to get optical glass from Focal Point Industries in Florida, but I've heard that there've been some issues getting stuff from them recently. I'd recommend calling them and not ordering from their website if you go that route. Another option would be to use low-e (i.e. white as opposed to green) picture framing glass. Any frame shop or glass store should be able to cut this to size for a reasonable amount. Make sure to talk to them about what you're doing and request a defect free sheet. If it's cut, have them sand down the edges so they aren't sharp. Edmund scientific might be a source, as would optical surplus places.

As long as your glass is the same thickness as the old glass, then the focus plane should be the same, although I expect your scanner has auto focus, and so a slight difference shouldn't be a problem. The scanning bed on my cezanne was 6mm thick, and so I made and adjustment. A good way to check is to make a scan with your current system at max optical resolution. It doesn't have to be of the whole negative. And then compare that to a scan with your custom scanning bed.

Make sure that whatever you build won't cause an obstruction in the scanner, and do put in little details that allow you to easily take it in and out of the scanner, as well as taking the glass in an out of the frame. I made sure to machine recesses that my fingers could fit in, which makes putting thinks in and out easy. Also, there is probably a calibration area of the bed that can't be obstructed. Check the OEM bed to find this area, usually way at the left side of the bed when you're facing your scanner. Make sure to machine out that area with your holder.

One more thing to be careful about, make sure that the MDF is totally sealed with shellac and paint, and allow this to cure for a good week before using it. You don't want any MDF dust getting in the scanner, and you don't want any out-gassing from the finishes clouding the optics of the scanner. (If you're worried about this, you could always build the bed out of black ABS sheet, but this will be much more expensive.)

Don't let these issues put you off. They are easily solved with some thought and a little patience. If you don't have experience using a router, you might want to enlist the aide of a local handy person.

[Deliberate1]

Peter, thanks for the detailed reply. I just took a close look at the scanner glass. Since I am not so handy as you, it seems to me that getting a replacement piece of glass the exact size of the OEM would be the easiest solution. I did not see any calibration slide on the glass bed, perhaps becasue the rig has a separate calibration slide that is employed during the installation process. I will also try to figure some sort of gasket to prevent seepage in to the machine. Did you do something like that? David

[Peter De Smidt]

Hi,

By calibration slot I meant a clear area on the edge of the bed that the scanner uses every time it's powered on. It's an area that you never want to block. Every flatbed scanner I've used has had one of these. This is different from a calibration slide. In any case, you're right that getting a big piece of glass might be easier. Make sure it's not too thin, as you don't want it to flex or break.

[Deliberate1]

Peter, thanks again. David