Originally Posted by sanking
Well, the Flextight makes 6900 dpi effective for 35mm film, this is an insane amount, and it makes +4.0D for Velvia... this is its sweet point, as the format gets large it shines less.
I've no doubt that a DSLR scanner can reach 10,000 dpi effective, it would require stitching even for 35mm, but it can be done with a bare $35 Nikkor-EL 50mm reversed, which is an insanely good lens.
"The third important parameter for a scanner is its density range (Dynamic Range) or Drange (see Densitometry). A high density range means that the scanner is able to record shadow details and brightness details in one scan. Density of film is measured on a base 10 log scale and varies between 0.0 (transparent) and 5.0, about 16 stops.[13] Density range is the space taken up in the 0 to 5 scale, and Dmin and Dmax denote where the least dense and most dense measurements on a negative or positive film. The density range of negative film is up to 3.6d,[13] while slide film dynamic range is 2.4d.[13] Color negative density range after processing is 2.0d thanks to compression of the 12 stops into a small density range. Dmax will be the densest on slide film for shadows, and densest on negative film for highlights. Some slide films can have a Dmax close to 4.0d with proper exposure, and so can black-and-white negative film.
Consumer-level flatbed photo scanners have a dynamic range in the 2.0–3.0 range, which can be inadequate for scanning all types of photographic film, as Dmax can be and often is between 3.0d and 4.0d with traditional black-and-white film. Color film compresses its 12 stops of a possible 16 stops (film latitude) into just 2.0d of space via the process of dye coupling and removal of all silver from the emulsion. Kodak Vision 3 has 18 stops. So, color negative film scans the easiest of all film types on the widest range of scanners. Because traditional black-and-white film retains the image creating silver after processing, density range can be almost twice that of color film. This makes scanning traditional black-and-white film more difficult and requires a scanner with at least a 3.6d dynamic range, but also a Dmax between 4.0d to 5.0d. High-end (photo lab) flatbed scanners can reach a dynamic range of 3.7, and Dmax around 4.0d. Dedicated film scanners [14] have a dynamic range between 3.0d–4.0d.[13] Office document scanners can have a dynamic range of less than 2.0d.[13] Drum scanners have a dynamic range of 3.6–4.5."
https://en.wikipedia.org/wiki/Image_...r#Scan_quality
“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
The Epson V700 scans perfectly CN and BW film +6 overexposed, which delivers densities under 3.0D.
This is the signal-noise vs density of the V700 before using Multi-Exposure.
+8 stops overexposure is also perfectly scanned if using Multi-Exposure, which works perfectly up to 3.4D.
Velvia won't show any quality in areas over 3.4D, but a drum or flextight will recover better that. Anyway normally there is no reason to pull that low quality detail, if the slide was not mistakenly underexposed.
Crap. I meant drum scanner.
Rick “fingers not connected to brain” Denney
Since I had my Cezanne on and some old negatives at hand I popped one of the black and whites I happened to have scanned with my old Microtek back in the day to see, and this definitely shows the differences in pretty stark "black and white" so to speak. I'm mostly a b&w shooter now, but back then I was shooting mostly chromes, so I don't have too many negatives to look at, but this tiny section on one of those was a great test with visible words. This is about 2.5 inch on the screen but would be a massive print of the full image. At a modest enlargement the differences don't show up as much. Maybe I'll rig up a quick camera scan later with my D800 and 55mm Micro at 1:1.
Again, not scientific, I just dug up some old raw scans from 7 years ago out of curiosity before I had the Cezanne, and rescanned them. None of the images are particularly good so they've languished in a binder.
Hi,
I don't believe there are any HP4 negatives that are worth scanning in my archive. I used it from time to time but way back then, and none of my good work in either medium format or LF was done with HP4. I did use it some wirth 12X20" format, but those negatives were typically shot at diffraction limited apertures of f/45 or greater.
If you send me a sample negative medium format to 5X7 I will be happy to digitize it for you with the a7r iv with pixel shifting, and return. If interested just contact me by email.
Sandy
For discussion and information about carbon transfer please visit the carbon group at groups.io
[url]https://groups.io/g/carbon
It's the Magnagon just the OEM industrial version with fixed iris of the APO-Rodagon-D 2x ?
https://www.closeuphotography.com/ro...gnagon-75mm-f4
"I have read a few times that the Magnagon is a re-badged APO Rodagon D 75mm M=1:1 lens but the APO Rodagon D 75mm 2X f/4.5 seems to be a lot closer of a match."
Here says "Constant optical quality at magnifications between 1:5 - 2:1", so to have 1:2 to 5:1 we just reverse the lens.
___________
And interesting review (with APSC) of x2 lenses:
https://www.closeuphotography.com/2x-lens-test
https://www.closeuphotography.com/mi...ite-5400-lens/
I found this is interesting information to learn about scanners... interesting data about Minolta DiMAGE vs Nikon old scanners.
If you'd rather contribute TMY-II scans, that's fine as well - I'd prefer people use what they are comfortable with, because they'll generally get the best results they can achieve with their setup, rather than working on sight unseen images.
I do have some TMY-II examples I scanned at 3000ppi on the X5 which can deliver visible granularity from TMY at that resolution, so I'll dig them out & append it to the set of comparisons.
I'm mainly interested in appearance & handling of granularity, rather than the sort of negatives often used as 'resolution' comparators - and a broader sample of films might actually help more in getting a sighting shot on the overall imaging performance of the pixel-shift scanning approach.
Lachlan, those have to be scans of MF film, as for 4x5" LF max hardware resolution of the X5 is 2,040dpi. As this is a LF forum it would also be interesting if you can also post 4x5" scans, to see how the hassie resolves TMY grain for LF.
Pere, I'm not interested in listening to you repeating the same tired (and self-evidently untested) statements over and over and over - just accept the following: you can get 3000ppi scans from almost full frame 4x5 on the X5 by shifting the negative and stitching - and very easily on 9x12cm. However, if investing in a pixel shift camera lets me get this sort of result faster and more easily, then that's what I want to investigate. Furthermore, I'd refer you back to Rick Denney's comments about the person who "couldn't get his head out of the pixels" because pixel resolution isn't the simplistic zero-sum game you want it to be. Pixel counts don't mean anything other than a set of arbitrary numbers if the rest of the optical performance isn't there.
Rather than hiding behind intentionally dishonest attempts at gatekeepering, how about you show (not tell, and with new evidence, rather than the same old scans) everyone how you can get your Epson to adequately resolve the granularity of HP5?
As a point of fact: for what I want to investigate, the format of the source material is (and should be) irrelevant. All that matters is: can a given scan system/ set up deliver a reasonable account of the source negative's granularity at a specified nominal pixel resolution comparable to what I currently work with, such that I should consider investing in a suitable shift/ stitch camera?
Posting Permissions
Reply With Quote
Bookmarks