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monkeymon
12-Sep-2014, 08:56
Is it normal, that on top of the lens inside Flextight there is this blue plastic gel filter? It's under the IR filter.

I find this odd, why does it need a blue filter as the light is daylight anyhow. And why is there a cheap looking gel filter (in my case a bit wrinkled even).. why did they not incorporate the blue color in the IR filter? Or at least use multicoated glass filter. Doesn't it affect the contrast?

Kirk Gittings
12-Sep-2014, 09:12
There is probably some forum somewhere dedicated to Imacon scanners where you might get a real authoritative answer to this. But why not just do a comparison scan with and without? Having said that personally I wouldn't try it. They get dusty and out of adjustment pretty easy and IME really need to be cleaned and adjusted at the factory but since it sounds like you have already been inside of it.

Richard Wasserman
12-Sep-2014, 09:21
There is an Imacon Users Group on Yahoo which you could join and get a definitive answer.

IMACONUSERS@yahoogroups.com

monkeymon
12-Sep-2014, 09:24
I know, but can't join yahoo groups. Tried it. Many many many times.

Actually the flextight is really simple machine. They do not get easily out of adjustment, and you can always run the focus calibration.

It's as simple as removing a lens from your enlarger. Paying for it, would be madness. Well, unless you actually bend the metal plate holding the lens. But that would require some force.

The way these things get messed up, is when the wheel inside get's somehow distorted. And the film is not always in the exact same focus spot.

The thing i like about flextights, is that they are simple machines & well thought. Like the use of magnets on the side panels... like it!

Kirk Gittings
12-Sep-2014, 10:01
Man I have seen a couple of friends and colleagues total screw one up just trying to clean the dust off the sensor and get them so out of focus that running the calibration can't get them back. I can't answer for their knowledge or dexterity though generally speaking they seemed pretty handy.

monkeymon
12-Sep-2014, 10:07
Man I have seen a couple of friends and colleagues total screw one up just trying to clean the dust off the sensor and get them so out of focus that running the calibration can't get them back.

Well, i have opened it several times. Cleaned the lens & have absolutely no problems. It solid, simple & well built system.

But i'm accustomed to doing all my repair work myself.

But there is no one here that has opened one up and noted the blue gel filter?

Richard Wasserman
12-Sep-2014, 10:34
I use an Imacon Precision III scanner, but I have never opened it up to look for filters. I don't know the purpose of the blue filter, but seem to remember that it has to do with scanning color negative film with the orange mask. It is a Kodak Wratten 80B, and yes it is for some mysterious reason gelatin. I agree it's weird using gelatin filters in the optical path.

monkeymon
13-Sep-2014, 02:11
I use an Imacon Precision III scanner, but I have never opened it up to look for filters. I don't know the purpose of the blue filter, but seem to remember that it has to do with scanning color negative film with the orange mask. It is a Kodak Wratten 80B, and yes it is for some mysterious reason gelatin. I agree it's weird using gelatin filters in the optical path.

Yes, it does look like a 80b filter. Well, if it supposed to be there.. maybe i'll spend a few dollars just to test relapsing it whit a multicoated glass filter.

Thanks for the confirmation!

Richard Wasserman
13-Sep-2014, 06:05
Please let us (me) know how it goes.


Yes, it does look like a 80b filter. Well, if it supposed to be there.. maybe i'll spend a few dollars just to test relapsing it whit a multicoated glass filter.

Thanks for the confirmation!

onnect17
15-Sep-2014, 18:18
I use an Imacon Precision III scanner, but I have never opened it up to look for filters. I don't know the purpose of the blue filter, but seem to remember that it has to do with scanning color negative film with the orange mask. It is a Kodak Wratten 80B, and yes it is for some mysterious reason gelatin. I agree it's weird using gelatin filters in the optical path.

Improving the response towards the blue channel to compensate for the orange mask makes sense. The lens (most likely a Rodenstock Magnagon 75mm f/5.6- fixed aperture) has a external thread with a cap to hold a circular filter of any thickness up to around 2mm, I guess originally designed for industrial equipment. Perhaps it was too expensive to insert OEM filters in the design. The 343 already comes with a glass filter.

monkeymon
21-Oct-2014, 18:34
Please let us (me) know how it goes.

The filter ended up being a 80A, but the multicoated glass filter does make a noticeable difference. Sharper & better contrast. Iäm running it now with the 80B i got... but i need more blue filtration. Actually i'm thinking about also adding a green filter. So it would compensate for colornegatives. The 80A filter is there just to balance out the CCD sensor, seems that the blue is not as sensitive as R & G.

Compensating for the orange mask would need a lot more filtration, more blue & a green filter. But anyhow, it's worth the effort to switch to an quality MC glass filter. Though you need to custom make an adapter for it from step up ring.

Richard Wasserman
22-Oct-2014, 09:02
Can you elaborate a bit please on what's involved in changing the filter? I've not looked inside and would appreciate some further information. Sounds worth doing—thanks!



The filter ended up being a 80A, but the multicoated glass filter does make a noticeable difference. Sharper & better contrast. Iäm running it now with the 80B i got... but i need more blue filtration. Actually i'm thinking about also adding a green filter. So it would compensate for colornegatives. The 80A filter is there just to balance out the CCD sensor, seems that the blue is not as sensitive as R & G.

Compensating for the orange mask would need a lot more filtration, more blue & a green filter. But anyhow, it's worth the effort to switch to an quality MC glass filter. Though you need to custom make an adapter for it from step up ring.

monkeymon
23-Oct-2014, 10:41
It's pretty simple job. Just open the thing up, it's 2 screws in the back. After that there is metal plate held in place with two springs. Then just remove the lens, it's held in place via threaded cap that is also a filter holder. Inside it, is the original blue filter and an a glass UV/IR or just an UV filter.

In the front of the lens, there is this rim you can unscrew. You needs to get a suitable sized step up ring (cant remember what size i used, something to 55mm), and remove the male threads from it. So that you just have an step up ring with a hole in it. Then you can place that in front of the lens & screw the rim in to hold it in place. Then you need a step down ring to get some height to it (so it clears the locking ring/rim. i used a 55-49mm), so you can put a filter on it. I did it so that it takes 49mm filters, as it's a size commonly available.

Richard Wasserman
23-Oct-2014, 10:51
Thanks for the explanation—I'll take a look inside mine as soon as I have a chance.



It's pretty simple job. Just open the thing up, it's 2 screws in the back. After that there is metal plate held in place with two springs. Then just remove the lens, it's held in place via threaded cap that is also a filter holder. Inside it, is the original blue filter and an a glass UV/IR or just an UV filter.

In the front of the lens, there is this rim you can unscrew. You needs to get a suitable sized step up ring, and remove the male threads from it. So that you just have an step up ring with a hole in it. Then you can place that in front of the lens & screw the rim in to hold it in place. Then you need a step down ring to get some height to it (so it clears the locking ring/rim. i used a 55-49mm), so you can put a filter on it. I did it so that it takes 49mm filters, as it's a size commonly available.

towolf
23-Oct-2014, 15:34
Would love to see how this scanner looks on the inside.

monkeymon
24-Oct-2014, 15:56
There is also one nice option i found out in the Flexcolor software, in the setup partition. Called "descreen", it's there to unfocus the lens. But it is an excellent tool for nailing the focus! The automatic focus calibration is not 100% accurate. At least on my machine, and with the descreen option, i can nail the focus 100% accurately. It seems the automatic focus calibration is usually off by 1-2 steps. So if you do a descreen scans from -3 to +3 you will see when it's in exact focus. Then just make custom setup files for different film sizes. As you need different descreen focus calibrations for 35, medium & 4x5" film sizes. It's really worth the trouble.

The MC glass filter & optimizing the focus with descreen is really was worth it. Now i get pin sharp grain, like i used to get on my schools X1.