Aperture for scanning 6x6

Help guys. I am using Sony a7ii. Best 55 2.8 macro lenses aperture for scanning 6x6 on copy stand set up. Thank you.

If thatā€™s a 55mm f/2.8 full frame Micro Nikkor lens, Iā€™d start at f/6.3 or so. On full frame, avoid apertures smaller than f/11. On APS-C, avoid apertures smaller than f/8. On Micro 4/3, avoid apertures smaller than f/5.6ā€¦ these recommendations avoid diffraction limiting of sharpness.

Most important is to photograph the EMULSION side of the film, rather than the base. This adds a step in post to mirror the image, but itā€™s worth it.

You need to take a series of sample photos at various apertures and select the sharpest. It isnā€™t rocket science. Once you know where the lens is sharpest and give the best results from corner-to-corner, set it and donā€™t change it. After all, why would you want to use the lens at a less than optimal aperture, right?

Or you could get Vladā€™s Test Target and test for yourself, very useful if you subsequently decide to try out a different lens (though much more useful for 35mm film copying). You can more subjectively inspect the grain across the image, particularly with a suitable B&W negative.

On the other hand I have that lens and Iā€™d also say f8 on full frame.

Me too f8, full frame.

I got one of Vladā€™s Test Targets and they are nice. As you say, inspecting the grain across the photo is absolutely essential.

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Thanks so much guys. Guess, f5.6 or f8 then.

After testing this proposition about which side of the film should be face-up or down numerous times, at least on my set-up, which is a very high resolution construct with some of the finest components available (https://photopxl.com/digitizing-negatives-with-a-camera-revisited/), I need to observe that there isnā€™t a scintilla of difference whether the media is emulsion side up or down. At 100% magnification, which one would never come close to seeing in a print, Iā€™m getting pinpoint sharpness of the dye clouds (so-called ā€œgrainā€) from either option. Here is an example of my latest retest of this proposition today:

Really interesting to see this demonstrated on a high end system. Iā€™ve never found it to be true either, and thatā€™s when I was using my Imacon, it deserves a separate post on its own really. In fact Iā€™ve never seen anyone give examples of how it might affect image quality now I come to think about it, even though they might hold strong beliefs that it does.

I think the logic of the ā€˜emulsion upā€™ theory is that the camera isnā€™t seeing the image forming particles, grain or dye clouds, through the film base, but in my view the light forming the image on the sensor is still passing through that film base in any case. Iā€™ve also seen it stated that it reduces the risk of reflection but there shouldnā€™t be a situation where there is a risk of reflection and if there is it can be dealt with by other means. Iā€™ve seen it pointed out that dedicated film scanners keep to that protocol. Perhaps they do but they may have other reasons for doing so and certainly they will want the scans to open in the right orientation in their software so guidance has to be given one way or another.

Yes, I think you got it right. The film is transparent interrupted by the varying opacity of the dye clouds forming the image, so when it is lit from below light passes through all this such that the contours and varying luminance/colour components of the dye clouds are what is recorded on the sensor, regardless of whether the emulsion is uppermost or below. If one were working correctly with this kind of set-up one should have no light from above that could cause reflections or extraneous colour casts, so that should not be a factor.

If anything, I would be inclined to theorize that a shinier surface facing the light table could induce reflection between the media and the light source, but I have not seen evidence of that actually happening either, so it reallt does seem to be awash.

Mark, Which way up do you scan?

Hi, I do emulsion side up. If anything, I find it easier to slide the neg into the slot of Skier Sunray Copy Box3.

My apologies on the typo. Yes, the lenses is 55mm f/2.8 full frame Micro Nikkor lens. Will try f5.6 this evening. Thank you.

Hi Graham; the emulsion side faces down just above the light panel, so shiny side up facing the lens.