Crop sensors, and Using Diopters

Hi all,

I’m working on a scanning setup using a Fuji X-t3 and the 60mm Macro.
I’m a little confused about the math when it comes to getting a 35mm to fill the frame and utilize the cameras full resolution. It’s something like 1:67 with a Fuji APSc, so I would ideally want what kind of magnification?
I’m looking at a Reynox and the Canon 500D, though they use different systems of explaining each system’s strength and I’m completely confused.

Also, has anyone used a diopter to get a better magnification and used stitching (mostly 120 but also possibly 35mm) for higher resolution?

Don’t have the cash for a 40 or 60MP camera–though I have thought about something with a sensor shift feature. Wouldn’t want that with every shot, but to have the option would be nice in case I want to print large.

Thanks!

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Rainer -

First, your sensor is APS, 1" wide, the 35mm film image is 1.5" wide, so to fill the digital frame your magnification will be 0.67x or 1:1.5

Quick check says the Fuji 60mm f/2.4 macro will focus to 0.5x or 1:2. You can use it at the closest focus and get good images, but you’ll waste some pixels. To get slightly more magnification, the best route will be a short extension tube, either the 11 or the 16mm will do the job.

(There’s another 60mm macro that focuses to 1x; if you have that one, no accessories will be needed.)

I suggest avoiding the front-of-lens accessory lenses; while there are exceptions, in general the image quality is degraded vs. a good macro lens with extension.

Thank you for the reply, sorry it’s taken me so long to get back.
Unfortunately, I’ve read several places the 60 Macro loses a lot of sharpness around edges with tubes, hence the diopter idea.
I haven’t been able to find a fuji 60 1:1…or is it another brand?

Was hoping to kill two birds and have a good scanning lens that could double as a portrait/short tele lens. Doing this on a tight budget, so maybe for now cropping some pixels away isn’t the worst thing. Will still get better quality than my flatbed, I’m sure.

Rainer, I suggest you simply use your lens, crop to the image area. You’ll waste some pixels, but probably will be pretty good on a budget.

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Thanks for your replies!
I ended up buying an older Micro Nikkor 60mm that has excellent reputation and goes to 1:1. I’ll let you know how it works out.

Curious what lens you ended up using and what the results were? I’m using the Fuji 60mm 2.8 macro with 16mm extension tube and noticing quite a bit of lost detail around the edges…

My results have been very good! I’ve had some minor issues with vignetting and color distortion at the edges, but only with thinner negatives, or those that are underexposed and have dark edges. Easily fixed with lens corrections, and the recently discovered (by me) flat field correction, both in Lightroom. You could try the latter before buying another lens.
You take a calibration frame of the diffusion over your light source (same fstop you will use just adjust the shutter speed to reduce exposure) then scan your roll and apply ‘flat field correction’ which senses the calibration frame at the beginning or end of the sequence (it must be in either of those positions) and it applies corrections to both luminosity and color shifts to all images.

For some reason the biggest issues I’ve had are with 120, tho I think it has more to do with the way I’ve been masking extraneous light. Still working on that. 35mm has been excellent.

It’s a super sharp lens, well made, Good feeling focus ring, and I’ve found that 60mm on the crop sensor is an ideal working distance for me.

I’ve read a lot about extension tubes causing problems like you’re describing. That’s why I went with the 1:1 Nikkor.
From what I understand while the adapters for legacy lenses do space the lens in a similar way to an extension tube, but they actually only compensate for the distance lost that would normally exist on a 35mm film camera (which the lens was designed for) between the rear element of the lens and the sensor on the camera. Therefore there aren’t the same vignetting issues as with an extension tube. Your technically using the lens as it was designed.

Hope that helps! I’m still figuring this out as I go along.

Thanks for the detailed reply! Curious what kind of light source you are using? I’m using my iPhone Xs (with True Tone, night shift off obviously). Should I just take an image of the iPhone screen for the “flat field correction” you mentioned? Or will I need to diffuse it somehow? What about taking an image of an exposed frame of the film being used?

I can get really close to the image with the 16mm extension tube (right up past the sprocket holes), but yes the distortion, vignetting, colour shifts and softness around he edges is pretty bad…

Hope it helps! This forum helped me set this up, happy to know I might be doing the same for someone else.

For backlight I use the Skier Lightbox, it’s an led panel lit system made for precisely this. Look it up, totally worth the investment to me.

Using a phone or iPad will work decently, but you will need some type of diffusion. Any kind of neutral colored frosted glass or acetate without texture, and you will need the film separated from the diffusion. Otherwise you will probably end up seeing the pixels of the Phones screen in your capture.
Best to get the Skier, or an LED light pad with good CRI and a film holder or tape your film to the surface of anti-newton ring glass.
There are lots of more helpful and detailed explanations than mine about light sources on this forum.

For flat field correction I first load a frame and focus on the grain, then remove the film and take a shot of the blank diffused light source. Because In my case the film is about 1/4 inch from the diffusion, when there is no film loaded I have an out of focus shot, which I capture, and there I have my calibration frame. Then I go about capturing the rest of the roll. This way you should be getting the closest to exact amount of distortion/vignetting since those issues are effected by what distance the lens is focused to.

Chances are, I think, that your light source is causing a lot of these problems.

Hope that helps!

Yes I’ve had my eye on a Skier Lightbox, but the high import duty fees here in Canada are making me apprehensive to pull the trigger. I was under the impression that you didn’t need to use any kind of anti-newton glass or diffusion when using the Skier. Isn’t it all set up to just scan away with?

I’ve actually gotten pretty usable results using the iPhone screen to be honest. I raise the film about 3 inches or so off the surface and get no pixels. Besides the soft corners and vignetting (which I attribute to using the 16mm extension tube to get proper magnification) I’m getting very sharp scans and with some colour tweaking, I’m pretty happy with the results from my first two scans. Def room for improvement though.

I’m kicking myself a bit because I almost pulled the trigger on a Nikkor 60mm macro, but got talked into grabbing the Fuji 60mm instead by the camera store rep. I’m curious what exact lens you are using? Might return the Fuji and go for the Nikkor after all if it does improve the vignetting and loss of edge to edge sharpness.

I’m also curious how bright the Skier box is? With the iPhone I find at f8 I have to use long shutter speeds. 1.5-2.5s to get the right exposure. Not sure if this would cause less ideal results or not? Is the Skier box bright enough to allow for faster shutters? Does it even matter?

Thanks again, I really appreciate your input as I am hoping to get good enough at these scans to avoid paying the $30/roll for high res TIF scans at my local lab!

The Skier is pretty much ready to go. The film holders are so so, but anything better you’d have to machine yourself, or spend $150 or up on, per film format. So I’m happy with it.
It’s extremely bright. I shoot at f8 or f11 and my shutter speeds vary between 1/30 and 250, depending on whether it’s c41, E6, or b+w, as well as density and such things.
You could probably order the same LED panel that Skier used and build one yourself. Pretty sure I saw the exact model posted somewhere on this forum.
I usually like to DIY just about anything, but the small form factor of the Skier made the decision for me.

I use the Nikon Micro Nikkor 60mm AF D. Chances are you’d have to order one on eBay as they’re older and far as I know out of production. Tho I think Nikon has a newer version. Mine was about $160, plus a $20 adapter.

If you’re getting good enough results that your happy with then go with what you got! Slow shutter speeds should only increase the chances of shake or blur. The one real issue (I think) with a screen like that would be CRI, which is color accuracy.

Try flat field correction and see if that helps enough before investing more than you want!

Hello again RainerM! Its been a while, but since your last reply I have gone ahead and purchased a Skier Lightbox and am very happy with it! Still using the Fuji 60mm macro though and the soft edges are still bothering me. Flat field correction fixes some of the vignetting and colour shifting as you mentioned, but it has no affect on the soft edges, which we talked about is due to the 16mm extension tube I’m using. I’m wondering if you could do me a favour and send some sample images of your scans using the Nikon 60mm macro AFD lens? I have a few options of buying it used but would like to make sure the results are much better then my current setup before pulling the trigger. Are you able to get right up close to the image using this setup? Like passed the sprocket holes close? Thanks again for all your help with this stuff, I have greatly improved my scanning over the last few months just from this thread alone!