That's very clean Peter - thanks for posting. Out of curiosity, is your DSLR able to see through the lines? On my tests, the lines are light grey as the scanner sees right through them.
Does anyone wish to see similar tests from Drum Scanners? I ask because the resolution is far greater and the test is silly to compare in my opinion.
Pali
Yes... it would be interesting. X5 flex can see Group 7 if doing 35mm, but a lot less with larger formats. It would be interesting to see where drums arrive...Originally Posted by Pali K
Hi Pali, I used Capture One's 'auto' tone curve and no exposure adjustment. Looking at the raw file, when the whites are at 250 the dark bars are at 33 with the linear tone curve. This is with Edmund's chrome on glass high resolution target.
“You often feel tired, not because you've done too much, but because you've done too little of what sparks a light in you.”
― Alexander Den Heijer, Nothing You Don't Already Know
I've rescanned the USAF target after realizing my camera was not focusing accurately. I have been using Autofocus and the D800E's autofocus fine tune is on -20, the end of its range. Even at this setting, the image was not in focus. If there were a -25, that would probably be spot on.
I manually focused the following image which is a slight improvement over my previous. In my version of the USAF target, group 5 corresponds to group 7 in Pere's and Peter's. Here I can read all of that group and perhaps the first element of the next group.
Peter's Rodagon image certainly looks good.
It looks like I will need to send my camera and lens together to Nikon for them to adjust the autofocus fine tune for this lens. It can be done for newer lenses, don't know about this one. Which leaves me to using manual focus for scanning. Not really a problem.
Here's the full image:
And the detail showing group 5:
Rich
Hey Rich,
At 1x magnification, using the lens to 'focus' changes the magnification instead. It's better to set the lens for 1x magnification, and then moving the whole camera + Lens system forward and back until the target is in perfect focus. I use a quality mm ruler to set the lens focus. Match the ruler reading to the size of your sensor, which'll give you 1x, and then don't change it.
Same thing as before, except this is with a reversed 50mm Componon-S at 2x magnification:
“You often feel tired, not because you've done too much, but because you've done too little of what sparks a light in you.”
― Alexander Den Heijer, Nothing You Don't Already Know
Peter, the exact magnification ratio is seldom important (at least to me). Focusing the lens itself is the only smooth focusing mechanism I have with my current set up. I don't have the camera on a focusing rail.
I know magnification changes slightly with the way I'm doing it. I had thought of adapting my view camera to hold the D800E body and making a lens board for the Micro Nikkor. But even my Sinar P back can't focus as smoothly as the helical focusing collar of the Nikkor.
My Z-axis:
I'd be surprised if any auto focus has the precision and accuracy to focus ideally at these magnifications. But I'd love to be wrong.
“You often feel tired, not because you've done too much, but because you've done too little of what sparks a light in you.”
― Alexander Den Heijer, Nothing You Don't Already Know
Wow I think I have to have one of those!
That and a usable live image. (D800E leaves a bit to be desired in the live focus department).
Does the Radagon have a focusing collar? I do have a helicoid adapter for F mount which I got for testing the various lenses I mentioned previously.
The camera and extension tubes are bolted to an Arca slide. Thus there is no helical in the system. The lens extension is set to focus exactly at 1x, which is ideal for my lens. With my D600, live view is not accurate enough to find perfect focus. I have no idea why. During setup, I do a series of exposures at different distances from the target, find the best one in my raw processor, and then fix everything at that point. The vertical stage is a Velmex 4000 series Unislide. A D800e should be able to get about 800 dpi more with the same lens setup than with my D600. (Daniel had a D800e and ran tests with it in a similar setup.) How much test slide resolution is practically helpful is a difficult question to answer. My guess is that many people overestimate how much detail they are actually getting one film. I scanned a purposely shot and highly detailed 35mm tech pan negative. Shot on a very heavy tripod with mirror lockup at my lens's best aperture. Such a setup should resolve significantly more detail than any LF negative. Doing test scans, I found that going up i, magnification (with lenses optimized for that) lead to better test slide results, but I couldn't see any advantage with the 35mm Technical Pan negative, which means that going after better results than I get with 1x with the Rodagon doesn't appear worth the effort, especially with larger film. My point is that since you're getting such great results with your current system, don't let test slide scans push you to spend more time and money chasing a dubiously useful improvement.
“You often feel tired, not because you've done too much, but because you've done too little of what sparks a light in you.”
― Alexander Den Heijer, Nothing You Don't Already Know
This is some 5000 or 6000 dpi, impressive
I also think this is a very good way to know what performance is needed or not, a good TP shot with a good 35mm glass is a safe reference...
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