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1 hour ago, Bill Kuta said:

But one link was from someone shooting at f4.5 (full-frame) who claims that it makes the dust/scratches very out of focus. I'm skeptical of this. But I'm going to try some test shots with a variety of apertures.

Well, if the scratches and dust are on the base, sure, focussing on the grain may help a bit.

Hang on, what if they're the other side? Doh.

If someone would care to test the DoF theory by scratching some film....... I use an antistatic brush, then a rocket blow, and sometimes a final blow when the frame is lined up. No shutter speed or ISO problems with flash.

Edited by spacecadet
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For 35mm slides, I've been wiping with a lens cloth, then with a lens brush, then a blower. Shooting with an APS-C Canon SL1, extension tube, 50mm macro, spacer ring, and ES-1, shooting into a florescent studio light.

 

For 120-size (6x6 cm) slides, I'm shooting with an APS-C Sony a3000 (great use for this odd model), extension tube, Sigma 60mm ART lens, and lightbox on a little copy stand. If the slide (all family shots from the 40's - 60's) is in a glass and metal mount, I remove it from the mount, wipe it with a PEC pad and 99% isopropyl, put it on the lightbox and cover (flatten) it with a piece of glass. Then I put it back in the mount. If it's in glass taped together with black tape, I don't disassemble that but wipe the glass and put it on the lightbox. 

 

Both setups allow me to do a zoom focus using the lcd.

 

I'll be doing test shots for both scenarios regarding apertures. The setup for the 120 slides assures flatness.

Edited by Bill Kuta
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17 hours ago, Bill Kuta said:

But one link was from someone shooting at f4.5 (full-frame) who claims that it makes the dust/scratches very out of focus. I'm skeptical of this. But I'm going to try some test shots with a variety of apertures.

It maybe a light collimation effect, and not an out of focus effect. I recently copied the same slide (and dust) with the light source at increasing distances away (nothing else was moved or changed). The further away the light source, the more clearly defined dust and scratches became. See pictures below. Using a lens at wide aperture will allow a large cone angle of light to enter the lens, whereas a small aperture will restrict the angle of light that can enter, increasing the collimation and potentially emphasizing dust and scratches.

 

Directional light (more collimated)

Directional.jpg

Diffuse light, less collimated.

Diffuse.jpg

 

But... using a wide aperture may cause DOF problems with non-flat or imperfectly aligned slides or with lenses with curved fields. For my slide copying lens (Leica 45mm macro) I found f5.6 was the best for overall sharpness, providing I aligned the setup carefully (using a mirror). My diffuse light source is about 10mm from the slide.

 

Mark

Edited by M.Chapman
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I did a little experiment this evening and found that there is virtually no depth of field effect on dust and scratches with my ES-1 and Tamron 90 setup. In fact I found that using apertures smaller than f11 (f16-f32), thereby increasing depth of field, was more effective at reducing marks or dust on the film, as the sharpness of the lens decreased. Of course the image quality was also significantly degraded at these small apertures. One thing I did notice was that reversing the slide had an effect. In the case of the slide I photographed, scratches were a lot less obvious with the emulsion side facing the camera, presumably because the scratches were on the other side. 

 

Another thing I discovered yesterday when I finally got my ancient Nikon LS4000 film scanner back in working order after a service was that scratches are far more evident on basic scans with no or only light IR dust removal with Vuescan (digital ICE in Nikon parlance) than with the camera copying method. It must be something to do with the optics of the scanner versus the camera I guess. Using heavy IR in Vuescan was more effective but softened the image a bit. 

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The Nikonscan 4000 and 2000 do a second scan when IR is turned on. The first scan is for the transparency normally backlit. The second scan is angled light only glancing across the surface of the film that highlights any dirt or scratches sitting on the surface.

 

The scanner software takes this second scan and uses it to apply a clone effect to the first final scan, to areas of dust that were highlighted in the second scan. This cloning results in a softening of the overall first scan. If the film is particularly dirty there is lots of cloning and the softening is even greater.

 

Look at the surface of Kodachrome with a glancing light and you can see that the surface is actually three dimensional. It looks like lines on a relief map. The glancing light from the scanner sees that relief as dust and scratches and tries to clone it out. This is why IR does not work well on Kodachrome.

 

I had a 4000 scanner and never used IR because of this softening effect. I cleaned the transparency as much as possible with Pec 12 solution, and then I did my own better cloning in photoshop.

 

I used a Canon 5D with a Canon 100mm macro lens in a copy setup for 4X5 film and the results were very good, particularly in dynamic range. As an experiment I went back and did some 5D copies of 35mm film that had been scanned on the 4000. The 5D copies were sharper, had greater dynamic range, and the process was much faster.

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4 hours ago, Bill Brooks said:

The Nikonscan 4000 and 2000 do a second scan when IR is turned on. The first scan is for the transparency normally backlit. The second scan is angled light only glancing across the surface of the film that highlights any dirt or scratches sitting on the surface.

 

The scanner software takes this second scan and uses it to apply a clone effect to the first final scan, to areas of dust that were highlighted in the second scan. This cloning results in a softening of the overall first scan. If the film is particularly dirty there is lots of cloning and the softening is even greater.

 

Look at the surface of Kodachrome with a glancing light and you can see that the surface is actually three dimensional. It looks like lines on a relief map. The glancing light from the scanner sees that relief as dust and scratches and tries to clone it out. This is why IR does not work well on Kodachrome.

 

I had a 4000 scanner and never used IR because of this softening effect. I cleaned the transparency as much as possible with Pec 12 solution, and then I did my own better cloning in photoshop.

 

I used a Canon 5D with a Canon 100mm macro lens in a copy setup for 4X5 film and the results were very good, particularly in dynamic range. As an experiment I went back and did some 5D copies of 35mm film that had been scanned on the 4000. The 5D copies were sharper, had greater dynamic range, and the process was much faster.

 

I agree about the camera copying being a lot better than the LS4000. I just got the scanner fixed (it was not expensive) to see how it would compare and it is not really in the same league as my copying setup (D810, Tamron 90 and ES-1 adapter with extension tube between lens and ES-1). Dynamic range is really important with slide copying and the camera is far better at holding detail in the highlights and shadows, moreover because I can shoot raw which also gives much better white balance. It is also much faster as you say. I will use scanner for a while for testing but might eventually sell it. It was great technology in its day but not now.

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