Auto focusing question on Nikon 9000ED

I recently acquired a Nikon 9000ED and plan to use it for archiving purposes. This forum has been really helpful but I have one question that’s unresolved and I’m wondering if someone could help me here.

I want to use the focus tool to select a point for the auto focus operation. In Preferences under ‘single scan,’ should I check or uncheck the ‘auto focus before scan’ option? In other words, does the scanner remember the point I selected or will it default back to the center of the image to do the auto focus before scan if I have it enabled? My gut feeling is that I should have the 'auto focus before scan’ option unchecked since the auto focus has already been done and no point redoing it again before scan.

Thanks in advance.

It seems to me that if you need to select a specific point on the slide or negative, then there's something wrong with the carrier flatness.

A scan should be grain sharp from corner to corner, regardless of the point chosen to focus. So if the autofocus doesn't do that, there's something amiss with the setup.

Scanning is a frustratingly slow process anyway, and if you're going to have to manually focus each image it'll take forever.

It seems to me that if you need to select a specific point on the slide or negative, then there's something wrong with the carrier flatness.

 

A scan should be grain sharp from corner to corner, regardless of the point chosen to focus. So if the autofocus doesn't do that, there's something amiss with the setup.

 

Scanning is a frustratingly slow process anyway, and if you're going to have to manually focus each image it'll take forever.

Thanks for responding! I read that to get the best scans, you have to focus on a high contrast area in the negative, like the eyes. Would you recommend just setting the option to 'auto focus before scan?' I'm new to scanning and all this is quite confusing to me. Unfortunately the manual doesn't offer much help.

I'm only planning to do the point focus on the most critical scans so time is not an issue here. Just trying to ensure that I have the best scans possible for those particular scans.

Thanks again.

I have both an LS-4000 (35 mm) and LS-8000 (MF), and I can tell you from experience that film supported at the edges will not be grain-sharp, corner to corner. A 35 mm slide in a cardboard mount bulges significantly in the center. Medium format film does the same and more. The standard MF holder grips the film at the edge and slides outward in order to stretch the film flat. That works pretty well, but not perfectly. Even if the film is flat, gravity is enough to spoil the focus. To get corner to corner sharpness, you need a glass carrier, which traps the film between two sheets, spaced about 0.2 mm apart. The top glass is textured for anti-Newton Ring effect. The bottom glass has an anti-reflective coating. Because it is on top, the textured glass has no effect on the image. I place the film emulsion side down, and have no problems with Newton's Rings.

I place the focus point about halfway between the center and the short edge (35 mm), or on a key element in the image, in the preview mode. Nikonscan software remembers where the focus should be on each image when the final scan is executed. That's true even if you have a strip or roll scanning model (e.g., LS-5000). You can set unique focus points in Silverfast too, but it's not as easy. You have to construct a batch operation.

You can make any setting the default, including the focus point.

I place the focus point about halfway between the center and the short edge (35 mm), or on a key element in the image, in the preview mode. Nikonscan software remembers where the focus should be on each image when the final scan is executed. That's true even if you have a strip or roll scanning model (e.g., LS-5000).

Thanks so much for this info. Exactly what I need! So for the preferences, would you suggest I enable "autofocus when focus point is moved" in “Automatic Actions” as well as "auto focus before scan" in "Single Scan?"

Many thanks again.

"The bottom glass has an anti-reflective coating."

- It's always bemused me why AR coated glass isn't the norm for scanners and enlargers. AR coating is fairly cheap these days - even multicoating.

Newton's rings are caused by reflection between the film's glossy surface and the adjacent glass, meaning that an anti-reflection coating can greatly reduce or eliminate the effect. Yet I've only ever seen AR glass film carriers in professional photo-printing machines (i.e. mechanised enlargers).

Anti-Newton glass of the type in the top layer of the Nikon carrier is etched with hydrofluoric acid to produce a slight texture. This treatment is relative non-reflective and prevents intimate contact between the film and glass. It looks slightly cloudy to the eye, but the texture is easily resolvable in the LS-8000/9000 if you omit the film.

I put the emulsion side down for two reasons. It is less reflective than the back, which has a mirror finish except for a few professional film types. Secondly the gelatin tends to shrink in dryer climates, causing the film to cup toward the emulsion. That way it only touches the lower glass at the edges.

You can buy anti-Newton glass on line, but in a pinch you can use non-reflective framing glass, available in most hobby shops. Some people have successfully modified the glassless Nikon carriers in this manner. You would not get Newton's Rings with ground glass, but the texture is far too coarse for this application. The lower glass (facing the lens) should be clear, coated if possible. I've used framing glass to flatten negatives on a flatbed scanner, using black construction paper as a spacer and mask.

I would select both options for auto focus. You won't see the first unless you refresh the preview, With regard to the second, it makes sense to focus before the scan. It is probably not desirable to focus between multiple passes. (It's better to be consistent than correct.)

I wasn't talking about anti-Newton glass; that's quite common. I was wondering why multicoated anti reflection coatings weren't in widespread use in scanner platens and enlarger carriers. The AR coating may even have some anti-static properties to help keep dust down.

AR coatings would seem to be a better solution than micro-dimpled AN glass.

I have a few 5" x 5" sheets of multicoated glass salvaged from a commercial printer. I haven't dared cut them to a useful size yet. You only get one chance at it!

I would select both options for auto focus. You won't see the first unless you refresh the preview, With regard to the second, it makes sense to focus before the scan. It is probably not desirable to focus between multiple passes. (It's better to be consistent than correct.)

Thanks so much again! I'll enable both those options. In the meantime I'll try to get a glass carrier. I absolutely agree, better to be consistent than correct.

Thanks again, really appreciate all your help!

I take it you do have a manual?

if not, or for others who may wish one:

https://www.nikonimgsupport.com/ni/NI_article?articleNo=000002102&configured=1&lang=en_US

The easiest (not necessarily the same as best) software is Nikon's own, but it requires an older version of either Windows or MacOS to run.

Yes, I do have a manual. Came with the unit. thanks for the link. I'm sure it'll be useful to others.

I finished the scans. These are some negatives on loan which I had to send back so it was critical I do them right. I was able to set the machine to do linear scans and thanks to Mr Ingold's advice, was able to focus on each frame individually. Many thanks to all who responded especially to Mr Ingold!