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Old 01-19-2017   #41
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Hmm... Looks pretty bad. So, the first scan is at low resolution and the one with the lines is at higher resolution?

Sorry, I don't have any ideas. The pattern looks to regular to be attributed to the dirty calibration area of the drum. I would suggest cleaning the contacts on the lamp sockets but I'm sure there would be streaking also in the low res scans if that was the culprit.
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Old 01-19-2017   #42
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Yes, first scan is at 1K DPI where there is no hint of the lines, second with the lines is at 2K DPI. Similar structure of lines at 4K and 8K. If the calibration strip or area were damaged which it does not seem to my amateur eye to be, wouldn't the lines appear in every scan?

I will try mounting some film on the other, cleaner drum that has original pads on it today to see if that improves the situation but as lubricating the lead screw did reduce the severity or depth of the lines, I'm thinking the fault is in the lead screw motor area.
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Old 02-06-2017   #43
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Made a bit more progress since last posting.

-Cleaned and cleaned again the pulleys for the drive belt.
-Cleaned and lubed the lead screw again.
-Cleaned and lubed the tailstock bearing.
-Cleaned the same drum I had been using.
-Re-did the DIY pads I had been using, slightly thinner so they were all within the small recess as the factory pads are. Before, some were slightly too wide which led to the drum not centering correctly on the tailstock.
-Cleaned the dust out from behind the FOPI, on that lens.
-Cleaned the lens on the other side of the FOPI, illuminator lens?

Now does 2K dpi scans with no hint of lines so that's a big relief.

Next thing to suss out is now when I set 4K DPI in Silverfast, it always returns an F702 error when checking lumens. At 1K, 2K there is never a problem but at 4K each and every time it pulls the error code.

Sample shot attached:

Wartime black paint Anniversary Speed Graphic
Black paint Kodak Ektar 127/4.7
HP5 in HC110 1:100 semi-stand
Blue painter's tape, dry mounted
Scanned at 2K DPI


Howtek D4000 Drum Scanner Lives Again by Anthony Gross, on Flickr
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Old 02-07-2017   #44
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The error indicates that there could be a problem with slow drum rotation speeds. Higher resolutions mean slower drum speeds. If you can hook it up to a PC you can run a test program to confirm.

Change the belt and see if that helps.
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Old 02-08-2017   #45
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Quote:
Originally Posted by Fixcinater View Post
Made a bit more progress since last posting.

-Cleaned and cleaned again the pulleys for the drive belt.
-Cleaned and lubed the lead screw again.
-Cleaned and lubed the tailstock bearing.
-Cleaned the same drum I had been using.
-Re-did the DIY pads I had been using, slightly thinner so they were all within the small recess as the factory pads are. Before, some were slightly too wide which led to the drum not centering correctly on the tailstock.
-Cleaned the dust out from behind the FOPI, on that lens.
-Cleaned the lens on the other side of the FOPI, illuminator lens?

Now does 2K dpi scans with no hint of lines so that's a big relief.

Next thing to suss out is now when I set 4K DPI in Silverfast, it always returns an F702 error when checking lumens. At 1K, 2K there is never a problem but at 4K each and every time it pulls the error code.

Sample shot attached:

Wartime black paint Anniversary Speed Graphic
Black paint Kodak Ektar 127/4.7
HP5 in HC110 1:100 semi-stand
Blue painter's tape, dry mounted
Scanned at 2K DPI


Howtek D4000 Drum Scanner Lives Again by Anthony Gross, on Flickr

I would take a look at the SCSI hardware and settings. Also the belt tension. Take a picture (or video) of the belt at work. Perhaps there's something to see.
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Old 02-09-2017   #46
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Belt tension was correct, too loose. I had thought it was a bit loose when first was inspecting the scanner before I started trying to use it. I adjusted it up a bit (not too tight as I'm well aware of adding bearing wear via excessive tension on drive belts/chains in other applications) and it's now scanning 4K seemingly happily.

I guess it's time to pay for Silverfast and actually start using the thing!

Thank you again for your help, onnect17 and brbo. I quite literally could not have done this without you!
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Old 02-09-2017   #47
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Quote:
Originally Posted by Fixcinater View Post
Belt tension was correct, too loose. I had thought it was a bit loose when first was inspecting the scanner before I started trying to use it. I adjusted it up a bit (not too tight as I'm well aware of adding bearing wear via excessive tension on drive belts/chains in other applications) and it's now scanning 4K seemingly happily.

I guess it's time to pay for Silverfast and actually start using the thing!

Thank you again for your help, onnect17 and brbo. I quite literally could not have done this without you!
Glad to hear you're now able to use the 4K and also being careful not to pass too much stress to the bearing in the motor.

I'm not a fan of the neoprene belts. Not enough elasticity. I prefer the ones made of silicone, but not too soft. I'm away from home right now but l will post the info later. You should give it a try.
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Old 02-12-2017   #48
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Originally Posted by onnect17 View Post
Glad to hear you're now able to use the 4K and also being careful not to pass too much stress to the bearing in the motor.

I'm not a fan of the neoprene belts. Not enough elasticity. I prefer the ones made of silicone, but not too soft. I'm away from home right now but l will post the info later. You should give it a try.
Mac Master part number 9396K304. I use it for the small Howtek scanners, i.e. 4000, 4500, 8000, etc. For the 6500/7500 the part numbers is 9396K324.

Happy scanning!
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Old 02-14-2017   #49
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Got a USAF 1951 target to test what resolution I'm getting from my H4500:



Resolution is not bad (if my math is good, I'm getting full 4000dpi). I guess I do have a problem with color channel alignment, though. Not using the dead center of the lens and therefore getting color aberrations?
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Old 02-15-2017   #50
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Got a USAF 1951 target to test what resolution I'm getting from my H4500:



Resolution is not bad (if my math is good, I'm getting full 4000dpi). I guess I do have a problem with color channel alignment, though. Not using the dead center of the lens and therefore getting color aberrations?
It looks more like the optical path is too wide (as it comes from the manufacturer) and some lateral scattered rays (produced by the grain in the emulsion) managed to get in. A very similar pattern is seen when using RGB leds as the light source without a diffuser.

Also the emulsion itself may be in not the best condition. Did you wetmount it? Is the scanned target a positive or a negative inverted?

Also, I noticed some compression in the image posted but not sure of the source. Jpeg?

Still, the image looks nice and sharp to me.
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Old 02-19-2017   #51
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Yes, it's jpeg and the target is dry mounted. I will repeat with my good drum (this one has slight crazing) and wet mounted. Also noticed this is a sample that I scanned in Silverfast at 8000dpi (I get a tiny bit better resolution that way?!). I might try making my light path narover if even the good drum produces this effect. What do you use for a light diffuser? Do you only use it for LED light source? Btw, do you have any side-by-side comparison between halogen and LED light source?

I've now bought DPL (it still hurt$$$). I'm pretty happy with scanning negative film at 4000dpi and 13microns. If I prescan as Wide Gamut Negative and then create custom profile (the Histogram's Auto Adjust tool picks up the end points nicely) all 12bits are then spent on real data in the negative. I almost have a finished picture straight out of scanner. No messing with ColorPerfect or Silverfast's NegaFix and I've found that I'm less prone to go down a "wrong" path when scanning/post processing negative film.

For example, I was reasonably happy with a scan from some time ago on my Minolta 5400 (scan as positive and ColorPerfect inversion):



I've rescanned the negative yesterday in DPL and arrived at this:



Higher contrast, cooler, grain is more visible, but I like it quite a bit better.
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Old 02-20-2017   #52
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A couple of scans of IT8:
https://1drv.ms/f/s!AugK5NQO79gPgyE2_05t_2c5nEWQ

Yes, I am using leds (XML-Color). I was never able to get a noise free scan at 6 microns with a regular lamp. To diffuse the light I use sand paper with a 400 grit or thinner directly on the surface of the led.

Remember to use the log mode with negatives. That's the only advantage of DPL. It used to be $400 and now it sells for $600. Still SF does a better job focusing.
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Old 02-20-2017   #53
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Thanks!

Do you use external power supply for LEDs?

Yes, SF enables you to pick the area which you want to use for focusing. I've found out that both DPL and SF missed focus a bit with my resolution target (DPL picked 146, my eyes (manually through viewport) suggested 143 (although everything from 143 to 146 looked the same to me) and the sharpest scan was actually achieved at 145). Evan from Aztek thought that unreliable autofocus could indicate hardware issue, weak lamp or user tampering with focused illuminator - that would probably be me trying to get more centered light beam on aperture wheel?!

In real world I don't think I would notice this, but it was evident with resolution target.
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Old 02-20-2017   #54
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Quote:
Originally Posted by brbo View Post
Thanks!

Do you use external power supply for LEDs?

Yes, SF enables you to pick the area which you want to use for focusing. I've found out that both DPL and SF missed focus a bit with my resolution target (DPL picked 146, my eyes (manually through viewport) suggested 143 (although everything from 143 to 146 looked the same to me) and the sharpest scan was actually achieved at 145). Evan from Aztek thought that unreliable autofocus could indicate hardware issue, weak lamp or user tampering with focused illuminator - that would probably be me trying to get more centered light beam on aperture wheel?!

In real world I don't think I would notice this, but it was evident with resolution target.
With the current design version I don't need an external power supply because the Howtek lamp driver brings 11v (not 8v as the specs show) so I connect the red, green and blue dies in series with a 2 ohm resistor. I do not use the white die. A small fan keep the temperature under control to avoid any color drift.

SF pick the focus in middle of the image, or you can select it manually. That's useful because you can pick a high contrast areas to focus. Besides, if your scanning area covers 8" of the drum, the focus at each end is different due to mechanical imperfections.

With DPL I do the same but manually. I scan first a small area and use the same focus value, entered manually with the intended larger scanning area.

I don't remember seeing any hardware problems with the focusing mechanism in the 4000 and 5000 dpi howtek scanners. I can't say the same of the 8000 dpi models. I would assume the difference is more related to the position of the surface of the drum at different rotation speeds. Also, a more centered beam only helps.
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Old 03-05-2017   #55
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So, classic case of one step forward, two steps back over this past weekend.

Finally took some time to RTFM and discovered how to get into FST on the MacUtil. I had used MacUtil after finding it in the files section of the Yahoo group to update firmware and that worked just fine. I ran the full set of tests in FST and passed all of them, much to my surprise. I made that last post and the day after, it started throwing a 702 error consistently and never worked on 4K again, hence my research and looking at FST.

Now, this is my most recent Prescan in SF, a shot of it while it is in pre-scan. Absolute gibberish. It does seem to produce the same gibberish each time I try it.

Any actual scans that I do are almost entirely black.

I took the top plate off of the encoder, thinking I might be able to get in there and clean as has been mentioned elsewhere. I removed the 4x Philips head screws where the encoder wire goes into the enclosure and once I saw it's not readily accessible, I replaced the cover, but did not adjust or touch anything else.

Any ideas on what I did?
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Old 03-05-2017   #56
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So you can pass all the FST tests and then do a prescan and get this in Silverfast?

Have you tried running Trident trial just to see if you get the same there?
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Old 03-06-2017   #57
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Yes, it passed the FST, ran it through the cycle a couple of times. Then the program itself hung up and I had to shut down the comp/scanner. That happened a few times. Trident/Aurora show the same sort of whatever that is but a different pattern in the scan itself.

Last night, I tried one last time and it showed mostly the same gibberish over the pre-scan area but it did show a few strips of the film/tape mounted to the drum.
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Old 03-06-2017   #58
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Quote:
Originally Posted by Fixcinater View Post
So, classic case of one step forward, two steps back over this past weekend.

Finally took some time to RTFM and discovered how to get into FST on the MacUtil. I had used MacUtil after finding it in the files section of the Yahoo group to update firmware and that worked just fine. I ran the full set of tests in FST and passed all of them, much to my surprise. I made that last post and the day after, it started throwing a 702 error consistently and never worked on 4K again, hence my research and looking at FST.

Now, this is my most recent Prescan in SF, a shot of it while it is in pre-scan. Absolute gibberish. It does seem to produce the same gibberish each time I try it.

Any actual scans that I do are almost entirely black.


I took the top plate off of the encoder, thinking I might be able to get in there and clean as has been mentioned elsewhere. I removed the 4x Philips head screws where the encoder wire goes into the enclosure and once I saw it's not readily accessible, I replaced the cover, but did not adjust or touch anything else.

Any ideas on what I did?

You have other problem. Double check everything you did, (cables you touched, etc.) I never managed to the get the Mac FST working. If you touched the firmware then make sure you used the right version (not the same file between Mac and PC)

Good luck!
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Old 03-06-2017   #59
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It isn't likely that I screwed up the encoder just by taking off the top plate where the cable runs in, right?

I guess that's my big worry right now. I'll go through and trouble shoot but would relax a bit if I knew it wasn't likely to have killed the $1500 encoder.
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Old 03-06-2017   #60
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It isn't likely that I screwed up the encoder just by taking off the top plate where the cable runs in, right?

I guess that's my big worry right now. I'll go through and trouble shoot but would relax a bit if I knew it wasn't likely to have killed the $1500 encoder.
Removing the cover does not break the encoder. Test it with the FST.
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Old 03-27-2017   #61
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2 week update, since last post I have repeatedly tried the MacUtil FST and could not replicate the single time it ran through all of the tests. It would always lock on test 5 or 6, and just sit there.

So, I've found a local Windows XP box and am setting that up now to run the scanner and will update again once I can run the full Windows FST and see what it says.

I really would prefer to run with a Mac box and maybe I will run Silverfast on it if I can get the scanner running smoothly with the PC to test.
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Old 03-28-2017   #62
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What are tests 5 and 6 called?

(sorry, I'm running my scanner with a headless winxp machine and if I want to run FST I need to attach monitor/keyboard)

Are you running FST from OSX? I never managed to do that...
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Old 03-28-2017   #63
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Sorry, I should have been more specific, it would fail on pretty much anything I started except for the first few tests. If I manually selected #17 (whatever that one is), for example, it would also fail but wouldn't get there if I selected all to run in a cycle.

I used it on OS 9, it would not run in OSX via Classic.
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Old 03-28-2017   #64
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Small update, plugged in the 2906 Adaptec PCI:SCSI card I had been using with the Mac and got it to actually scan something in Silverfast demo mode on the Windows machine. Still had some patchy random jitter in the pre-scan and scanned result but it's at least talking and forming some sort of image compared to the total mess it was when I put up the screen shot before.

Odd thing, it shows up in Silverfast demo mode and scans; in Trident demo mode it shows up and I was able to change to the PC-specific R535 firmware as it had the Mac file loaded; it doesn't show up at all in the FST. Will dig a little deeper again tomorrow.

Also, just wanted to say thank you again to everybody here, especially BRBO and onnect17. I'm super grateful for the time you've spent. Hopefully I can get this thing fully sorted and pass the knowledge forward to keep these things running.
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Old 03-28-2017   #65
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Hmm... I never thought it needed a PC-specific firmware. Is there a source of this information? I was running the same firmware on Mac and now on the PC (R813 I think).

I'd try a different SCSI card and cable. I'm sure onnect17 will have a better guess at what else could be your problem...
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Old 03-29-2017   #66
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The Howtek file page on Aztek's site shows a Mac file and a PC file for every scanner, and onnect17 warned about the same. I don't know any more than that.

I have seen that the Adaptec 2906 card (which I have) has a rather poor reputation so changing it may indeed bring some results.
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Old 03-29-2017   #67
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Talking about the firmware for the scanner. I have no doubt the resulting binary code in the flash memory in the scanner is the same, via PC or via Mac. However, the internal. format of the source files with the hex code used by the FSTs could be different.

Keep in mind also the scsi cards BIOS could be different. Yes, many have a version for PC y otra for Mac.

The jitter is most likely mechanical.
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Old 04-05-2017   #68
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Quote:
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Yes, I am using leds (XML-Color). I was never able to get a noise free scan at 6 microns with a regular lamp. To diffuse the light I use sand paper with a 400 grit or thinner directly on the surface of the led.
Hi!

May I ask what is the reasoning behind going with a RGB led instead of single white? I'll go ahead and try to build a led light source and would just like to understand what I am doing. Why, for example, this wouldn't work:

http://www.cree.com/led-components/p...cxa1304-8def74

Thanks!
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Old 04-06-2017   #69
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Hi!

May I ask what is the reasoning behind going with a RGB led instead of single white? I'll go ahead and try to build a led light source and would just like to understand what I am doing. Why, for example, this wouldn't work:

http://www.cree.com/led-components/p...cxa1304-8def74

Thanks!
Sure. The layers in the color film are "tuned" to be the most sensitive to Red, Green and Blue, so the ideal light source to "read" the info would be a pure RGB, in order to minimize the crossover and get the highest color purity. The white leds actually are blue leds with a phosphorus coating to radiate in the green-to-red area of the spectrum, carrying the unwanted yellow-orange portion.
Once you get the XML-Color based light source working then scan an IT8 target and look at the RGB numbers (using PS or similar), particularly at the pure read, green and blue patches. Then compare it to a any other light source scan of the same target.
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Old 04-06-2017   #70
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Thanks! Obviously, I don't know what range of wavelengths the RGB parts in the LED cover. Hopefully they cover all the ranges of the dyes that are used in various films.

Deltas after making a profile from IT8 target with halogen and then LED source might tell us something about that, but some other real world scans of films might still be somewhat "off" when scanned with less than full spectrum, no?

One more thing, do PMTs need to be cleaned (the surface) from time to time?
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Old 04-06-2017   #71
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Thanks! Obviously, I don't know what range of wavelengths the RGB parts in the LED cover. Hopefully they cover all the ranges of the dyes that are used in various films.

Deltas after making a profile from IT8 target with halogen and then LED source might tell us something about that, but some other real world scans of films might still be somewhat "off" when scanned with less than full spectrum, no?

One more thing, do PMTs need to be cleaned (the surface) from time to time?
It does not have to cover the full red, green or blue. Actually, a fully monochromatic RGB light source built with laser would perform even better but some issues related to coherence could be introduced.

If I understand it correctly you do not need a yellow light source to get the yellow out of a flower in the color film. The emulsion recorded it as a combination in the red and green sensitive layers.

The surface of the PMTs should be fine, unless the scanner is being used in a really dusty environment. Humidity, salinity, etc. could be a bigger issue. I remember seeing an aperture wheel with some corrosion in the 30 microns hole, blocking half of the light.
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Old 04-07-2017   #72
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If I understand it correctly you do not need a yellow light source to get the yellow out of a flower in the color film. The emulsion recorded it as a combination in the red and green sensitive layers.
Sure, there are blue, green and red sensitive layers in the color slide and negative films, but I've only heard about yellow, magenta and cyan layers present after developing the film. As far as I understand it, the CMY dyes then act like filters. When shining the light through the film magenta dyes block the green spectrum, yellow dyes the blue... and so the original scene is reproduced. Now, in the perfect world containing RGB spectrum (of the original scene) respectively in their designated RGB layers of the film would be 100% perfect. The dyes after developing would be perfect filters (100% blocking of one and 100% transmission of the rest of the spectrum). In this case I can see how a RGB light (with narrow peaks) would be able to recreate the original scene.

In reality, though, I think there is far more "leakage" at original recording of the scene in their respective RGB layers in film, dyes are far from being able to perfectly "cut" the spectrum to desired range of wavelengths. But that's ok. Film manufacturers have developed many different methods to solve those issues and, probably most important for our case, live with them. They actually rely on all those issues or even introduce them so they can create various "characters" in films. For example, they might observe that the blue layer is underrepresented in the exposed film, so they would just use dyes that would block less of that spectrum, but they don't want to totally cancel out the original problem etc...

Now, in those cases a broad visible spectrum is actually needed/prefered to "inspect" the film, because the film was designed (I know, another assumption) to be observed under that kind of light.

(I'm perfectly aware that this all might be total bul****, I'm no expert, just using _my_ common sense.)

edit: Interesting link on this subject...

Quote:
Originally Posted by onnect17 View Post
The surface of the PMTs should be fine, unless the scanner is being used in a really dusty environment. Humidity, salinity, etc. could be a bigger issue. I remember seeing an aperture wheel with some corrosion in the 30 microns hole, blocking half of the light.
Ok, I won't bother with getting to the PMTs for the time being.

The aperture was actually my next question. How to be sure that my 60mic aperture actually is 60mic and not narrower. And what to do about it if that is the case...
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Old 04-07-2017   #73
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Sure, there are blue, green and red sensitive layers in the color slide and negative films, but I've only heard about yellow, magenta and cyan layers present after developing the film. As far as I understand it, the CMY dyes then act like filters. When shining the light through the film magenta dyes block the green spectrum, yellow dyes the blue... and so the original scene is reproduced. Now, in the perfect world containing RGB spectrum (of the original scene) respectively in their designated RGB layers of the film would be 100% perfect. The dyes after developing would be perfect filters (100% blocking of one and 100% transmission of the rest of the spectrum). In this case I can see how a RGB light (with narrow peaks) would be able to recreate the original scene.

In reality, though, I think there is far more "leakage" at original recording of the scene in their respective RGB layers in film, dyes are far from being able to perfectly "cut" the spectrum to desired range of wavelengths. But that's ok. Film manufacturers have developed many different methods to solve those issues and, probably most important for our case, live with them. They actually rely on all those issues or even introduce them so they can create various "characters" in films. For example, they might observe that the blue layer is underrepresented in the exposed film, so they would just use dyes that would block less of that spectrum, but they don't want to totally cancel out the original problem etc...

Now, in those cases a broad visible spectrum is actually needed/prefered to "inspect" the film, because the film was designed (I know, another assumption) to be observed under that kind of light.

(I'm perfectly aware that this all might be total bul****, I'm no expert, just using _my_ common sense.)

edit: Interesting link on this subject...



Ok, I won't bother with getting to the PMTs for the time being.

The aperture was actually my next question. How to be sure that my 60mic aperture actually is 60mic and not narrower. And what to do about it if that is the case...
Based on my short experience and IMHO the biggest sources of color error is not related to different manufacturers. It has to do more with:
- Emulsion condition, i.e. proper storage.
- Light temperature control during shooting.
- Film development quality.

Once I got control of it you could hardly see the difference between E100G and 100F.

Regarding the 60 microns aperture wheel, the automatic gain adjustment in the amps makes it hard to compare it the other apertures. The only way I know is a physical inspection under the microscope. In practical terms, I would no bother with it. The optical box in the 4000/4500 is a lot better built than the one in the 8000 (with the 30 microns aperture).

Now, remember the PMTs pretty much convert photons energy in a current-then-voltage value. Well, because the color bandwidth of each channel is narrower with an RGB light source, the amps operate with a better SNR. I must say I was quite impressed with the image coming out the scanner the first time I used the RGB led. Previously, using the standard lamp the level of noise with the 60 microns aperture was quite high, to the point that I used the 130 microns most of the time.
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Old 04-12-2017   #74
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I've ordered "white" and RGB leds. It will take a while to get them. I will then compare and see what works best...

How's it possible that flickering is not a problem with LEDs if you are using the existing power supply for halogen bulbs?

Thanks!
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Old 04-12-2017   #75
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I've ordered "white" and RGB leds. It will take a while to get them. I will then compare and see what works best...

How's it possible that flickering is not a problem with LEDs if you are using the existing power supply for halogen bulbs?

Thanks!
I am using the same 11v DC feeding the halogen lamp. The xml-color has 4 dies r,g,b and white. I don't use the white.

I am sure you can handle basic electronics. Here's the list of components I am using in this design. I am sure other members can come up with a better approach.

- Heat sink + fan. The Howteks are able to compensate for small changes in the light source but it's better to keep a lower and stable temperature. It's also used as a base.

- Arctic Silver™ Thermal Adhesive. To attach the led and the resitors to the main sink.

- Capacitor. 0.1uF is fine. Just to be safe with any noise introduced by the fan.

- 2 x 1 ohm metallic resistor. That will allow around 900 mA into the leds.

- Fiber optic coupler. I make these ones in a minilathe using teflon and then cover with hi-temp metallic paint.

- Molding silicone. To cover the "whole-thing"

Perhaps a picture of a few lamps in the middle of being built ... ;-)

https://1drv.ms/i/s!AugK5NQO79gPgyyqi7XoH464u6Nl
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Old 04-19-2017   #76
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So the white led (still waiting for the rgb led) doesn't work any better than the stock halogen bulb. It's true that I don't have a good way to get all the light to the optic fibre, I just place the led close to the optic fibre (the reflector I got for the led doesn't really focus the light to a small enough spot like the original lamp).

I asked about this before... Would you be willing to sell one or two of your rigs?
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Old 04-20-2017   #77
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So the white led (still waiting for the rgb led) doesn't work any better than the stock halogen bulb. It's true that I don't have a good way to get all the light to the optic fibre, I just place the led close to the optic fibre (the reflector I got for the led doesn't really focus the light to a small enough spot like the original lamp).

I asked about this before... Would you be willing to sell one or two of your rigs?
Where are you located?
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Old 04-20-2017   #78
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Where are you located?
Slovenia (EU).
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Old 04-21-2017   #79
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Slovenia (EU).
Send me your name and postal address to *******************
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Old 05-28-2017   #80
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Hmm... Started getting vertical banding (only in red channel). Swapped lamps, made sure calibration area is clean.

Any ideas?
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