Film-Tech Forum ARCHIVE: Scanning film is out of focus.

This is topic Scanning film is out of focus. in forum Film-Yak at Film-Tech Forum ARCHIVE.

To visit this topic, use this URL:
https://ft-forum.com/ft/cgi-bin/ubb/ultimatebb.cgi?ubb=get_topic;f=8;t=006374

Posted by Randy Stankey (Member # 64) on 02-18-2011, 01:26 AM:

I'm trying to scan a whole bunch of old 35mm slides onto the computer. There are 150 of them. Kodachrome & Ektacrhome in pasteboard mounts.

Two days ago I scanned the first batch of 25 without problem. Got the capturing done in about an hour. Got decent results.

Today, I tried to scan another batch and almost all of the images are out of focus. Tried several things with negative results:

*Cleaned the scanner glass.
*Cleaned the film holder.
*Defaulted the software settings.
*Upgraded the scanning software to the latest version.
*Reinstalled the scanner driver.
*Tinkered with settings.

Some pictures come out okay. Some are blurry and out of focus.
Tried rearranging slides on the platen. Tried some other things.

It boils down to one of two things, I think:

1) The scanner is beat.
2) The film is cupped too much.

Using Canoscan 8800F flatbed scanner.
I know this is not an ideal scanner for film, by any means, but I have always been able to produce good scans with it before. 1,200 dpi to produce a 1,500 x 1,000 pixel image from a 35mm slide should be well within its capability.

I'm scanning slides originally taken in 1974. A mix of Kodachrome and Ektacrhome.

I can scan a page of a magazine and resolve down to the rosettes that make up the image.

I can scan a frame of B/W 35mm negative and resolve down to the dust specs on the film. I doubt this scanner will resolve film grain even if I turned it up to 9,600 dpi.

If I can do these things, the scanner MUST be working all right. I suppose the only thing left is the film.

Right now, the outdoor temperature is 45-50ºF and 35% humidity.
I can see some cupping in the film. Indoor temperature is about 65ºF.

Yesterday, it was colder. I don't know what the humidity was but it was probably a bit higher.

It seems weird because the pictures scanned well yesterday but, today, they come out crap.

I put the film away for the day. I wrapped it up inside a plastic bag with a damp piece of paper towel inside. I put it on the shelf in a closet. I'm hoping a day of acclimating will improve results.

I don't know what else to do. This is supposed to be a paid job.

Anybody have ideas?

Posted by Bobby Henderson (Member # 840) on 02-18-2011, 10:46 AM:

Unfortunately this problem is pretty common. The primary issue is the film itself curling just a little. It does that in film holders for flatbed scanners as well as holders for individual slides. That throws off the scanner's ability to focus properly. The problem can happen in flatbed scanners and dedicated slide scanners.

Wet mounting film strips in a drum scanner will provide the best results. It's not a good solution for casual scanning, but it's great for professional needs (maximum detail, dynamic range, no Newton Rings in the scan, etc.).

Posted by Randy Stankey (Member # 64) on 02-18-2011, 11:41 AM:

If I had a drum scanner or if anybody within an hour's drive from here had one that they'd rent time on I'd be all over it like the stink on a skunk! [Wink]

Unfortunately I can not unmount these slides. They were taken in 1974 in Africa during the Eritrean Civil War. One of a kind. Somewhat historically significant.

Once scanned, the slides will be stored safely and only taken out when needed. The scans are so that the images can be used without risking damage to the originals. They don't need to be super-duper high rez.

The goal is to get the images scanned and digitally remove the dust so that they can be used in multimedia presentations and things like that. 1,500 px. wide images should be sufficient for that purpose. A 1,200 dpi scan should be more than enough to produce a good image.

This should be well within the capability of a good flatbed scanner.

I've been scanning 35mm slides, 35mm negatives, 120 negatives and even the occasional 4x5 negatives for two years without a problem. It caught me off guard when this happened but these are old Kodachrome slides. I'm guessing they are more prone to cupping than more modern film. Do you think?

Strangely, I've scanned Kodachrome from the 1950s without incident. It must be the weather.

I guess it's time to build a humidity chamber. Eh?

Posted by Ron Funderburg (Member # 4561) on 02-18-2011, 12:32 PM:

Just a consideration and probable expensive but have you thought of having new prints made and do the scans from the prints. Of course, you have to find a photo shop that actually does prints and not just a computer scan and printer print!

Posted by Bobby Henderson (Member # 840) on 02-18-2011, 01:02 PM:

It's surprising what temperature and relative humidity can do to screw up a graphics project. It can affect all sorts of materials, such as the ink in a large format printer. If we're printing graphics for a vehicle wrap we try to get everything done at once during the same day. If the print job is spread out over numerous days the differences in weather can create differences in output and make seams in the finished wrap painfully obvious. Climate control is important but there's only so much you can do.

quote: Ron Funderburg
Just a consideration and probable expensive but have you thought of having new prints made and do the scans from the prints.

The downside of this approach is "reflective art" like photo prints, paper, etc. have at best only half the dynamic range of transparent film negatives, slides, chromes, etc. You'll get richer color and superior contrast by scanning transparencies.

Posted by Ron Funderburg (Member # 4561) on 02-18-2011, 01:06 PM:

For sure it isn't like the days of Norman Rockwell when he would cover a mistake with masking tape and paint over it. Progress!

Of course the slide is preferable but if he can't get it and wants them preserved that might be a solution. Just put it there for consideration!

Posted by Randy Stankey (Member # 64) on 02-18-2011, 01:54 PM:

The humidity chamber is working. I put the whole lot of slides inside a large, plastic Tupperware container along with a damp sponge then put it in a warm place.

Rearranging the slides on the platen helps. Either arrange them at different spots in the scanning rack or rotate them landscape or portrait for best image.

Another little trick is that I took a piece of thin matte board and cut a hole in it with a craft knife that's just a bit bigger than the opening of the slide. If I get a slide that doesn't want to scan, I place the matte board under the slide and raise the film up a few millimeters. That seems to help getting most of the film back into the zone of focus.

I got the first 50 slides scanned this morning. Now I have to crop and touch up the dust spots. (No, infrared cleaning doesn't work all the time. You still need to do occasional touch-ups.) By the time I finish this batch the rest of the slides will probably be humidified enough that I will be able to scan them.

Hopefully, I'll be able to go back to batch scanning again.

Posted by Ron Funderburg (Member # 4561) on 02-18-2011, 02:05 PM:

Randy I wish you luck! [Smile]

I wish I had all my old slides and negatives. I have some old family photo's (I mean pre-me old) that I need to scan as well.

Posted by Steve Guttag (Member # 268) on 02-18-2011, 05:39 PM:

<---has been known to print from slides though it has been a while.

Posted by Randy Stankey (Member # 64) on 02-19-2011, 08:13 PM:

Something's wrong... [Frown]

I scanned a bunch of slides yesterday and they all came out right. Then, today, I go to scan some more and they are all screwed up again.

I don't think humidity is the culprit. The slides have all been in a humidity chamber since the day before yesterday. (No, they aren't buckled the other way from too much humidity.)

Just out of frustration, I unhooked the scanner and flipped it upside down to look at the bottom. I put it back down and scanned a slide. It was good. I scanned the same slide a second time and it was bad.

So, I flipped the scanner over and tried again. Good.

If I pick the scanner up, flip it over and set it down again, I'll get one good scan out of it. If I want to do more, I have to flip it over each time.

The scanner is beat, I guess... Dammitt!

Posted by Louis Bornwasser (Member # 3063) on 02-20-2011, 10:00 AM:

Maybe glass mounts can help??? Louis

Posted by Kenneth Wuepper (Member # 1174) on 02-20-2011, 11:28 AM:

Randy,

Perhaps there is wear or grit on the scanner rails and that makes the imaging device move differently each time.

Since you have inverted the scanner and it works until the mechanism settles back on the rails, can you try to operate it in the inverted position?

KEN

Posted by Randy Stankey (Member # 64) on 02-20-2011, 04:35 PM:

If these weren't one of a kind slides I'd be more willing to experiment.

I'm not even touching the film with a cleaning brush. Only canned air. The idea was to use infrared cleaning to remove the dust that isn't removed by the air jet. It's been working well until the damned scanner crapped out on me.

I have borrowed another scanner but it's the next model older than the one I own. It has a cold cathode lamp instead of LED. I don't have a color target to profile the scanner with either. I borrowed a color target to profile my scanner with and, because it's got an LED light source, it stays pretty stable. I gave the color target back when I was satisfied that I had a decent color profile that worked the way I wanted it to work. (I'm not doing super critical work that requires me to profile the scanner on each job. A couple times a year is more than enough.)

Right now, I need to get these slides scanned because I promised to return the originals by Monday. (Tomorrow.) Once I have the slides digitized and stored on computer I can crop and retouch, etc. at my leisure.

So I'll get the slides scanned in and I'll just spend a bit more time adjusting the color by hand with Photoshop. So far, the automatic color balance controls of Photoshop have been doing an acceptable job of producing a color balance that looks good to the eye, considering that they are 35 year old film images.

Once I get this job done I'll see if I can tinker with my scanner and get it working again.

Cross my fingers... Maybe there's a screw that I can adjust or a bushing that I can replace which will fix it up long enough for me to buy a proper film scanner.

Posted by Steve Guttag (Member # 268) on 02-20-2011, 09:52 PM:

Though a long way around the mountain...why not project them using a slide projector and then take a digital picture of them. By blowing the slide up in this manner, you are likely to get a higher resolution version anyway.

It isn't going to be perfect and you will have the color of slide projector light to deal with but that is likely correctable (take a white reference picture too (no slide...just the white light of the projector).

-Steve

Posted by Randy Stankey (Member # 64) on 02-20-2011, 11:31 PM:

I own more than 80 cameras.

One of them is digital.

It is a 2.1 megapixel Canon Digital Elph, pocket size camera.

I also own 5 or 6 slide projectors, too.

On the bright side, I just finished scanning the last slide and I have 100 out of 150 edited to JPEG. I use a standalone scanning program and I can Photoshop the pictures while the scanner runs in the background.

At least I can return the slides to the owner tomorrow but, if I hustle, I might even be able to deliver the finished product too! That would be cool!

Posted by Steve Guttag (Member # 268) on 02-20-2011, 11:49 PM:

Now I'm a film-guy too. However, in addition to my film based cameras (Nikon and Canon), I now also have a Nikon digital. I shoot with both film and digital. There are times where digital has its advantages, the same with film. And with what you were doing, having a decent digital camera would be a good investment. Of course, my slide-projector to film camera technique would have worked too...the problem being, you would have had to wait for processing to see if you really got the picture...with digital, the answer would have been instant. Also, once you got your technique down (color correction and other filtering)...you could then repeat that on all of the rest of the slides.

In fact, one of things I'm considering doing for "scanning" of large paper (bigger than legal) is to just shoot a picture of it and then convert that to a suitable (paper) sized version rather than shell out for a large-format scanner (it is amazing how expensive even going to 11x17 flat-beds cost, and sometimes it is "D" or "E" sized paper I want turned into electronic form.

-Steve

Posted by Randy Stankey (Member # 64) on 02-21-2011, 12:21 AM:

My scanner (when it works) will scan negatives as wide as 120 but I have been able to scan 4x5 negatives with it.

I scan in two passes, making sure there is at least 1/3 overlap then import to Photoshop via "Photomerge" and treat the two half-images as if they are tiles of a panoramic shot. But for having to make two passes with the scanner, the computer does most of the work.

I like digital cameras too but I have so much film stuff that I just don't have a place for a digital camera, let alone the budget for it.

If I need to, I can take film out of the camera and have it developed and contact printed in a couple of hours. I don't worry about missing the shot. If I really need to get it, I'll bracket and shoot twosies of everything. If it's a one-chance event, the probability that you'll get the shot is the same whether you shoot digital or film, anyway.

Even though I learned on 35mm SLRs with TTL metering, most of the cameras I have don't have internal meters. They are either TLRs (like a Roleiflex) or rangefinders. Even the ones that have meters aren't coupled.

It's really funny how you never think you'll ever learn to take pictures with one of those "old cameras" but, after one or two rolls of film you start to just develop the knack for it. If you can incident light meter the scene you can work up an exposure setting that will work and then interpolate around that area. If you can take spot readings, meter the light and dark areas and use those two extremes as a range to set exposures with. Once you get the hang of it you can just look at a scene and know what exposure to use.

The meter I use most often is a Gossen Luna Pro. I can just take one or two readings of the general scene lighting and once I get into the groove I don't need to take any more readings until I shoot a new scene.

The weird part is that, when you go back to a camera with TTL metering, you start looking at the readings and saying, "Naah!," then putting the camera on fully manual operation.

For copying slides off a screen, I'd take two sets of photos to calibrate whie balance. One pure white against the screen and another with a gray card illuminated by the slide projector light.

No, I don't own a "Whi-Bal" card. [Frown]

Posted by Steve Guttag (Member # 268) on 02-21-2011, 10:39 AM:

As odd as it may sound...I'm pretty sure I do have a grey card specifically for checking white balance. I can't remember when I last used it or even where it is. You are right, of course, one should not only measure the full white but also grey...However, it would probably be best to have the grey be projected (i.e. have a slide of measured gray scale) and check the range.

-Steve

Posted by Randy Stankey (Member # 64) on 02-21-2011, 10:52 AM:

At the photo studio I worked at during the holiday, they would take two photos to balance the cameras each day. One was the white seamless backdrop. The other was a "WhiBal" card. A white, black and neutral gray card all in one. (Supposedly, every WhiBal card is measured with a spectrometer when it leaves the factory.)

I just have a regular, old 18% gray card but, most of the time, I shoot black and white so a critical reference isn't necessary. Just so long as middle gray hits zone V on film.

Posted by Scott Norwood (Member # 30) on 02-22-2011, 08:37 AM:

I am coming in late here, but one option would be a slide duplicator (Bowens Illumitran or Durst Chromapro or similar) with a digital camera. You could rephotograph the slides and probably get similar results to what the scanner would provide at a higher speed. The digital camera could probably be borrowed or rented if you don't have one.

Posted by Bobby Henderson (Member # 840) on 02-22-2011, 09:14 AM:

I use an 18% gray card to set custom white balance with my 5D Mark II. The camera's light meter in the view finder works well enough, but sometimes I'll cheat and use the histogram in live view to dial in the exposure just right.

Auto white balance isn't very good at all with most cameras, especially if you're taking numerous shots that will be used together in the same spread -lots of fun with slight color differences from shot to shot. If you shoot in RAW you can manually change the color temperature to the same setting in all of the shots, but it's easier to just set a custom white balance and be done with it. Custom white balance is a must if you're going to shoot some time lapse stuff for video.

Posted by Randy Stankey (Member # 64) on 02-22-2011, 12:13 PM:

I try to do everything in RAW format.

When I use a digicam, I set it to RAW if it is available. When I scan anything except for documents I intend to convert to PDF, I set my scanning application to store as RAW.

If I can shoot, scan or convert to DNG I will do that if possible. (DNG = "digital negative" which is a subset of the RAW format which is supposed to be more cross-platform compatible for archival use.)

I find that shooting/scanning in RAW allows you to get your color balance, exposure and detail set pretty close to what it needs to be before you even start editing. Once it is loaded into Photoshop, you usually only need a few minor tweaks like shadow/highlight correction and a quick curves adjustment to get it where you want it.

Luckily, I was able to borrow a scanner to finish the project with. I'm done and I just delivered this afternoon. Now, I'm probably going to disassemble my busted scanner and see if I can figure out what's wrong with it. I'm hoping that it's just something that's misaligned which I can just put back and be done.

Otherwise, I'll have to get a new scanner. That will eat up all the money I just made doing this project. [Frown]

A good digicam would be nice to have but the budget won't support that purchase for the foreseeable future. [Frown]

Posted by Mike Blakesley (Member # 26) on 02-22-2011, 01:52 PM:

This thread makes me realize (again) how much I don't know about photography and light. I wonder how much better my "images" would be if I actually knew something!

Posted by Randy Stankey (Member # 64) on 02-22-2011, 02:34 PM:

What's the problem? You, pretty much, take a projector and turn everything around backwards and you have a camera! Projectors and cameras are virtually the inverse of each other.

Think about it for a second. [Wink]

Posted by Steve Guttag (Member # 268) on 02-22-2011, 06:54 PM:

And to an electrician...indistinguishable.

Posted by Randy Stankey (Member # 64) on 02-22-2011, 07:15 PM:

Consider that electricians work with alternating current. And, since, at any instant, alternating current could be flowing in either direction, for all intents and purposes, you could say that it is flowing in both directions, simultaneously. (Think about Shroedinger's Cat.)

Therefore, electricity is flowing both forward and reverse at the same time.

Because electricians think in terms of forward/reverse at all times, they would naturally think that a projector and it's inverse, the camera, exist simultaneously in the same space.

That's why electricians call projectors "cameras."

See? It all makes perfect sense when you think the right way! [Wink]