European glass not available in the US

[Katastrofo]

Glass is termed "European glass" and is thinner than our single strength
window glass and more importantly, is ground on one side. How expensive
is this glass in GB and Europe? I was looking for 2 pieces 8.5"x 11.5".

Bill

[Attila]

http://www.dokasphotos.com/techniques/ground_glass/

this one ?

[Katastrofo]

Yep, that is where I found info on how to grind down our own glass, but
was wondering how expensive is the real thing. The procedure set forth
in the link could have high FOF (Failed Operation Factor).

[Attila]

I try to understand and ask my local dealer

[Katastrofo]

Thanks, Attila!

[peterqd]

Bill, I've never heard of "European glass" over here. All normal window glass here these days has to be at least 4mm thick for safety, but I think it might still be possible to buy 3mm "agricultural glass", used in greenhouses. The only glass 2mm thick I know about is "picture" glass, maybe you could get a couple of cheap photo or picture frames?

[Katastrofo]

Peter, that sounds like a good idea! I wonder if some picture glass is
ground on one side for antiglare... I'm using these for negative/positive holders for scanning. I'm going to call around to different glass places,
and if they don't have any glass ground on one side, will try grinding my own from single strength window glass.

[peterqd]

[Katastrofo]

Thanks, Peter, some ideas to consider!

[Richard_D]

You can also buy frosting spray - don't know how well it works...

It might be worth trying your local picture framers to see what they've got.

[Katastrofo]

Found a picture frame company that stocks non-glare glass and can cut
it any dimension from the 11x14" blank. Will see what shakes.

[Attila]

Great!

[Katastrofo]

[Katastrofo]

Here's a quick and dirty scan to see if it works. For masking I used heavy
construction paper, flat black, comes 50 sheets to a pack for $1.99 at
Staples, 9x12":



Some dust, didn't clean up all of it, and probably from using a strip of
emory cloth to dull the glass edges. Pic is a little over-exposed, will try
some others. How is sharpness in this?

Bill

[maddog10]

Looks good on my monitor, but I am getting older (and not wearing my glasses)

Are you just laying the strips on the scanner, without a holder, and using the glass to flatten them?

[Katastrofo]

No, the negs are taped to the cut glass and it has thin black cardboard
squares in each corner. The film is taped to the glass shiny side of neg touching glass, then I horizontal flip in PS. Needs tweaking, but am
somewhat encouraged.

[Katastrofo]

After doing some comparisons with the stock filmholders, it's back to the
drawing board. Betterscanning beckons...

Here's a comparison of stock filmholder and using the frame glass:

filmholder


frame glass


Both scans, same settings, just resized and some sharpening is all.

The frame glass must have a coating, not ground like I hoped. Gives a very aberrant histogram with a quarter inch gap! Trying to cure it's hazy glare and lack of contrast was a waste of time. Oh well. I think any coating, or using magic tape, would yield the same crappy or crappier
results. Just an FYI.

[maddog10]

Was the glass thickness correct? The holders are designed to hold the negative a certain distance from the scanner lens. Very noticeable difference between the samples.

[peterqd]

I don't think I really understand what you're attempting here Bill. Why do you need to have a coated or ground glass between the scanner lens and the film? If you need to use glass for mounting, wouldn't it be best to use plain clear glass with the film below it? (i.e. with the film sandwiched between the platen and your glass). That way the glass wouldn't affect the scanner definition. All you'd need to do is make sure the film is spaced away from the glass to avoid Newtons rings and to get proper focus.

[A G Photography]

You need this:

http://www.betterscanning.com/scanning/insert.html

[Katastrofo]

Alessandro, I mentioned Betterscanning in my above post and am familiar
with Doug's offerings.

Mike, thickness of glass is not that important, distance from scanning bed
is, and determined by the cardboard pads in each corner of the cut glass.
I'm using this much like the ANR glass where you have the curved side of
the negative facing the cut glass where it is taped flat to it and facing
towards the scanning bed. Something is giving me killer glare, either from
the coating on the cut glass which I'd hoped was ground but isn't or the
masking I'm using (construction paper). The construction paper I positioned
on other side of cut glass and it wasn't taped down, just resting on the cut
glass. I'll try a few more things, but I think the culprit is in the coating on
the glass.

Peter, in my above setup, am I doing something drastically wrong?

Bill

[maddog10]

Is light leaking in from the sides? The holders somewhat keep this from happening. Did you try it with the white background, instead of the black?

[Katastrofo]

The one thing or actually two things I'll try is no masking whatsoever, or
tape the masking down on the same side as the negative. Here's a scan
where the negative is resting right on the scanner bed held down by coins,
nothing else:



This is using the the Epson 2450. If it was 1mm above the scanning bed,
sharpness would've been improved. But there are no glare or contrast
problems.

Bil

[Xpres]

Bill - You mention ANR glass. Couldn't you use that? I use a 5x4 piece in the neg carrier of my enlarger - it came with it, but surely can't be that hard to get hold of. ebay maybe?

[Katastrofo]

Xpres, I can get ANR glass from Betterscanning, but they are cut for
specific filmholders, nothing larger.