p.1 #1 · Viltrox Z Extension tube set solved a slide scanning problem
I have a huge project involving many hundreds of slides to copy with my Nikon Z7ii and Tamron Z 90mm Macro lens. I improved my setup's efficiency and accuracy recently with the acquisition of a Valoi 360 Professional kit and their Slide holder attachment. The 360 setup is ideal for 120 film too, but that's not the subject here.
It was always irritating that with my particular rig, when focusing sharply on a slide, some of the slide mount must get included (1:1 math I guess ). So when I open the file in ACR, I have to manually crop out the slide mount, which also reduces the image resolution from 45.4MP to around 40 something - a loss of 5MP.
In many cases, honestly, that loss is immaterial but not always. Plus I have to take the time to fine tune the crop.
So I bought the Viltrox 12 / 24mm auto-extension tube set and used the 12mm tube. It took some time but I finally had it all aligned where the barest little bit of image gets cropped out to create a clean scan while retaining the full resolution of my Z7ii.
I use Nikon tether and auto-focus and auto-exposure all work fine.
I scanned a slide of my old college library (62 yrs ago). The 1st one is what I get without the extension tube and the 2nd one Is what I automatically get now.
p.1 #3 · Viltrox Z Extension tube set solved a slide scanning problem
Did you check sharpness of the results with extension tube vs without + crop?
Extension tubes can cause issues as the lens is not designed for them and are usually not the way to go for reproduction of flat surfaces. Maybe you can get away with the 12mm one on a 90mm lens though.
p.1 #4 · Viltrox Z Extension tube set solved a slide scanning problem
fjablo wrote:
Did you check sharpness of the results with extension tube vs without + crop?
Extension tubes can cause issues as the lens is not designed for them and are usually not the way to go for reproduction of flat surfaces. Maybe you can get away with the 12mm one on a 90mm lens though.
Thanks for this info, but if true in my situation, the sharpness differences are a wash to my old set of eyes. My college library shot is not super crisp in sharpness (but enough to tell me I want the white sports car) but in the "post your images scanned from slides or film" thread, I posted a sharp image of a small glacier.
That scan INCLUDED PORTIONS OF THE SLIDE FRAME, so I re-scanned it with the 12mm extender to exclude the slide frame and cropped both down to about 1/4 the image area and attach below. The original scan may have slightly more contrast.
My judgement of the importance of the extension tube is a matter of speed and efficiency vs. any optical factors. The Valoi slide holder has a minute amount of "wiggle room", so I can insert slide and adjust quickly to remove any evidence of the frame in the tethered live-view and hit the expose button and DONE.
Again, I like the fact I can keep virtually the entire original image in the scan with the fine adjustment I have made and I'm not touching it until all the slides are done.
Dave
Crop of original scan that included some of the slide frame
). So when I open the file in ACR, I have to manually crop out the slide mount, which also reduces the image resolution from 45.4MP to around 40 something - a loss of 5MP.
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