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DannyTreacy
18-Oct-2017, 08:32
Hi all,

I've been looking into alternatives for wet scanning using when Dura-Lar/Mylar to sandwich the negative, really to see if I can find a cheaper item that does the same thing as Mylar or Dura-Lar.

I'm aware that Mylar is just a product name invented by DuPont who produce it so if anyone knows what Mylar basically is that would be great.

I'm based in the Uk and I contacted a company who supply different plastic sheets for many trades, they suggested a product called Melinex (also made by DuPont), I got a sample sheet and I wondered if anyone else had experience of scanning with Melinex?

The sample I got is 75 microns thick, as oppose to 125 Mylar which i have previously used, I guess scanning is the only way to tell if it's a suitable alternative. be good to know if anyone has tried it though.

Thanks.

Doug Fisher
18-Oct-2017, 09:02
One thing I would do first is to do a test with the material and your mounting fluid to make sure it doesn't melt the material. Then I would test with an old negative to make sure it doesn't stick too much.

Doug

sanking
18-Oct-2017, 09:39
First, Mylar is a trade name for clear, uncoated, polyester film. Dura-Lar is similar, clear polyester, and is available in a wide range of thickness and sizes. It works fine for fluid mount scanning and I can not imagine you could save much with another product.

Mellinex is also polyster but most types have some type of coating for accepting inks. I actually use Mellinex 339 as a support for single transfer carbon but the material I use is quite expensive compared to clear polyester.

If you are unable to buy Dura-lar in the UK, just do a search for clear, uncoated polyester. 3 mil thickenss is about perfect for fluid mount scanning.


Sandy

DannyTreacy
18-Oct-2017, 10:44
One thing I would do first is to do a test with the material and your mounting fluid to make sure it doesn't melt the material. Then I would test with an old negative to make sure it doesn't stick too much.

Doug

thanks Doug I'll try that.

DannyTreacy
18-Oct-2017, 10:46
First, Mylar is a trade name for clear, uncoated, polyester film. Dura-Lar is similar, clear polyester, and is available in a wide range of thickness and sizes. It works fine for fluid mount scanning and I can not imagine you could save much with another product.

Mellinex is also polyster but most types have some type of coating for accepting inks. I actually use Mellinex 339 as a support for single transfer carbon but the material I use is quite expensive compared to clear polyester.

Thanks Sandy, the Melinex I have is # 516 and is 75microns thick. Any ideas if that's suitable? It appears to be clear.



If you are unable to buy Dura-lar in the UK, just do a search for clear, uncoated polyester. 3 mil thickenss is about perfect for fluid mount scanning.


Sandy

DannyTreacy
18-Oct-2017, 11:11
Thanks Sandy, the Melinex I have is # 516 and is 75microns thick. Any ideas if that's suitable? It appears to be clear.

sanking
18-Oct-2017, 12:17
Thanks Sandy, the Melinex I have is # 516 and is 75microns thick. Any ideas if that's suitable? It appears to be clear.


Mellinex 516 appear to be a clear polyester treated on both slides to prevent slip.
http://www.marianinc.com/wp-content/uploads/2013/10/pdf-data-sheet-MELINEX®-516.pdf

It should work, but before risking negatives pour some of your fluid mount solution on the surface and leave it for a few minutes before wiping it off. Also, you might heat it a bit as some scanning produces heat.

Since you have a sample try it, but there is no reason to believe it would work better than plain polyester with no coating.

Sandy

Pere Casals
19-Oct-2017, 07:44
First, Mylar is a trade name for clear, uncoated, polyester film. Dura-Lar is similar, clear polyester...
Sandy


Hello Sandy,

Just an addition, polyester is a family of polymers, Mylar is a member of this family: polyethylene terephthalate (PET), with an special mechanical extrusion treatment.

Mylar, Melinex, and Hostaphan are different brands for the same polymer of Biaxially-oriented polyethylene terephthalate , called BoPET .

PET is Biaxially-oriented to be BoPET by mechanical a extrusion process from the raw PET material.

https://en.wikipedia.org/wiki/BoPET

Plastic botles for soft drinks are also commonly made of PET.



PET repels water, for wettability characteristics (like Grafix ) of PET a surface treatment may be applied, like plasma or UV excimer light: http://www.nature.com/pj/journal/v43/n6/full/pj201120a.html

PET wettability is also critical for emulsion coating, for DIY film, Denise explains it in TLF, were I learned that.

I guess that for scanning wettable PET is undesired, as mounting fluid is (non polar) oil.

Regards

DannyTreacy
19-Oct-2017, 12:19
Hello Sandy,

Just an addition, polyester is a family of polymers, Mylar is a member of this family: polyethylene terephthalate (PET), with an special mechanical extrusion treatment.

Mylar, Melinex, and Hostaphan are different brands for the same polymer of Biaxially-oriented polyethylene terephthalate , called BoPET .

PET is Biaxially-oriented to be BoPET by mechanical a extrusion process from the raw PET material.

https://en.wikipedia.org/wiki/BoPET

Plastic botles for soft drinks are also commonly made of PET.



PET repels water, for wettability characteristics (like Grafix ) of PET a surface treatment may be applied, like plasma or UV excimer light: http://www.nature.com/pj/journal/v43/n6/full/pj201120a.html

PET wettability is also critical for emulsion coating, for DIY film, Denise explains it in TLF, were I learned that.

I guess that for scanning wettable PET is undesired, as mounting fluid is (non polar) oil.

Regards

Er, so it's ok to scan with Melinex??!

Pere Casals
19-Oct-2017, 13:17
Er, so it's ok to scan with Melinex??!


Hello Danny,

Sure that the right type of Melinex should be ok. But you have to take (IMHO) the good type.

I found this here: http://www.katco.eu/uk/site__1347/

Melinex® 401 - optically clear film
Melinex® 505 - optically clear, printable film


IMHO some types of Melinex can be better or worse for you.


You sure know that a substance can be lipophilic or hydrophilic. Raw Melinex is lipophilic so it is good for your mounting fluid.

Some Melinex types are treated in the factory to be hydrophilic (wettable) instead, in this way those sheets can be printed with water based inks, IMHO this kind of Melinex are bad for scanning, as its surface repels oil.


So IMHO the 401 type should work better than the 505, because the 505 repels oil (I guess) and this should make harder to evacuate air bubbles.

IMHO when a Melinex type is said "printable" it may be hydrophile, so the wrong kind for you.

Here there is all types... https://www.tekra.com/products/films/polyester-films/polyester-pet?page=1

For the 516 type that Sandy is pointing it says:

Good handling properties
High clarity
Brilliance

It says nothing about printing, so it should be of the good type for you.



In my case, I coat my DIY film with my DIY emulsion (still testing), so instead I need sheets of the the other type than you, because photographic emulsion contains water and no oil, so the type that is good for you it would bring problems to me as it would not help to spread water emulsion, and forming separate drops on it.


Regards

DannyTreacy
21-Oct-2017, 01:09
Thanks for the info Pere!

The Melinex is £30 for 200 A4 sheets, whereas the Dura-Lar is £96 for the same amount, so it's less than a third of the cost.

Pere Casals
21-Oct-2017, 04:51
Thanks for the info Pere!

The Melinex is £30 for 200 A4 sheets, whereas the Dura-Lar is £96 for the same amount, so it's less than a third of the cost.

Not at all, it was also great for me discovering Melinex, I was not aware it was the same (BoPET) than Dura-Lar. Still I'm messing with glass for dry plates, but I'll also try Melinex with side by side with Dura-Lar when I engage DIY film making.

Regards

Rich14
21-Oct-2017, 15:15
Hi all,

I've been looking into alternatives for wet scanning using when Dura-Lar/Mylar to sandwich the negative, really to see if I can find a cheaper item that does the same thing as Mylar or Dura-Lar.

I'm aware that Mylar is just a product name invented by DuPont who produce it so if anyone knows what Mylar basically is that would be great.

I'm based in the Uk and I contacted a company who supply different plastic sheets for many trades, they suggested a product called Melinex (also made by DuPont), I got a sample sheet and I wondered if anyone else had experience of scanning with Melinex?

The sample I got is 75 microns thick, as oppose to 125 Mylar which i have previously used, I guess scanning is the only way to tell if it's a suitable alternative. be good to know if anyone has tried it though.

Thanks.

Danny,

What size film are you scanning? What kind of scanner (drum or flat bed?)

We never used mylar film for drum or flatbed scanning. We scanned 35mm up through 8x10 using only the film itself and Scotch "Magic" tape. We used nothing but pharmaceutical-grade mineral oil as the scanning fluid. The "mounting station" for scanner drums need be nothing but a plastic cradle to hold the drum on a light table.

I'd be glad to describe the technique if you're interested.

Rich

DannyTreacy
22-Oct-2017, 01:17
Danny,

What size film are you scanning? What kind of scanner (drum or flat bed?)

We never used mylar film for drum or flatbed scanning. We scanned 35mm up through 8x10 using only the film itself and Scotch "Magic" tape. We used nothing but pharmaceutical-grade mineral oil as the scanning fluid. The "mounting station" for scanner drums need be nothing but a plastic cradle to hold the drum on a light table.

I'd be glad to describe the technique if you're interested.

Rich

Hi Rich,

I'm scanning 5x4 and 10x8 using an Epson 850 (flatbed).

Be good to hear about your technique.

Thanks.

Adam Long
22-Oct-2017, 13:17
Danny, have you found a supplier in the UK then?

I've tried both with and without overlay. Without is quicker (for a single sheet), simpler and very slightly sharper in my experience. However if you're doing batches the overlay is quicker, and has the benefit of keeping all the taping outside the scanning area on the drum. I you tape within the scanning area - as with single sheets and no overlay - it's very easy to scratch the drum when removing the film.

DannyTreacy
27-Oct-2017, 08:29
Danny, have you found a supplier in the UK then?

I've tried both with and without overlay. Without is quicker (for a single sheet), simpler and very slightly sharper in my experience. However if you're doing batches the overlay is quicker, and has the benefit of keeping all the taping outside the scanning area on the drum. I you tape within the scanning area - as with single sheets and no overlay - it's very easy to scratch the drum when removing the film.

Hi, I'm not drum scanning, I'm flat bed scanning. Thanks