I'm fairly sure, but it may depend on choice of film, humidity, etc. My 8x10 experience was with Ilford HP5+, emulsion side down.Originally Posted by Dirk Rösler
I only place images on the glass when scanning for a proof. When scanning in earnest, I always use my BetterScanning holder.
Yeah, me too. I just bought a V750 in May, it'd be nice to be able to just get the improved holders if possible.
I thought the V750 only did about 2400 DPI and that 3200+ was interpolation? Wouldn't that make this lens/scanner higher?
Why the heck didn't they implement some kind of double scan system for 8x10!!! Ugh....
I didn't expect that they would make a lens big enough for 8x10, but they could've at least enabled us to scan with two separate scans and have the system merge them or something using the "good" lens, and at least provide a holder etc.
Scitex/Creo/Kodak had a patent on scanning via multiple passes and stitching. It might still be in effect.
Changing topics, is the measured 2400 dpi that an Epson can achieve apply to sizes larger than 35mm? I bet it doesn't.
“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 doubt it. The optical resolution (that is, as limited by the CCD; the lens and mirrors will likely reduce this, so the effective optical resolution will be lower) of the v700/750 is the same as that of the newly announced v800/850, which is 33% more than the older 4990, which was 4800dpi. The basic architecture of the device hasn't changed between the 4990 and the 700 series, and it likely will remain the same in the v800. I expect only upgrades of perhaps the optics themselves and most likely of the CCD. Looking at the CCD resolution, some educated guesswork puts this in the range of ca. 25,000dpi, corresponding with a pixel size of roughly 1um. This corresponds to what we see in consumer-level tiny CCD'sin digital compact cameras - with of course the notable difference that for a scanner, the CCD will be a strip and for a camera, it's obviously a rectangular arrangement.
On the topic of real-world resolution, keep in mind that the specified CCD resolution is most likely (certainly) the combined resolution of all three arrays (red - green - blue). If you divide the v700's 6400dpi resolution by 3, you end up somewhere in the low 2000s. Coincidentally, this is in the same ballpark where informal testers put this scanner. Obviously, this will be similar for the new v800/850 and it will be limited to the same ca. 2100dpi resolution as its predecessor. Further increasing that would certainly be possible from a perspective of CCD manufacturing, but the demands on the optics (and most importantly, their alignment and tolerances in a real-world manufacturing setting) would be higher as well. Even in current scanners, the optical system needs to resolve roughly 500 line pairs per mm. This is already 10 times as much as the resolving power most high-quality medium format lenses.
That really depends on the construction. E.g. the older 4990 used only one lens that is in a fixed position. In other words, for a smaller format, the scanner simply reads out only a part of the CCD array and the optical resolution will be the same regardless of the width that is being scanned. I understand that the v7x0 (and I assume the 8x0 as well) use two lenses. I expect they use one lens to cover the full width of the scan bed and the other lens, with a higher magnification, to project a narrower strip onto the same CCD, effectively increasing the optical resolution for that area.
What I definitely don't know, is if this second lens is moved and re-focused depending on the actual width that is being scanned. I expect not; otherwise they could have resorted to using a single, movable/refocusable lens (sort of a zoom lens, essentially). That means that the same optical resolution will be available regardless of the actual width of the 'high-resolution' zone that is being scanned. I.e., the actual optical resolution will be the same, whether you scan 35mm or 4x5". If the lens is moved (and the projection circle made smaller or larger depending on the area to be covered), the optical resolution will likely be higher for smaller formats. But like I said, this is quite unlikely given the relatively low complexity of the optics usually found in contemporary flat bed scanners.
Perhaps someone with more knowledge of specifically these scanners (or someone with a screw driver and a v700 at hand) can chime in on this and point out where I missed the bat.
The second lens does NOT move, hence the need for something like the BetterScanning holders for the V7x0 to position the holders just right for the 2nd lens.
It's only of academic interest. I have a resolution target, but I no longer have a consumer scanner.
“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
Whether or not the resolution improves with the 800/850, seems like there are other avenues of improvement that could occur. Since the introduction of the 700/750, there've been advances in noise reduction, the ability to render shadows, electronic filtering, etc., in cameras. It would be neat if some of these advances could find their way to scanning.
Why use any kind of negative holders at all? Since you have the 750 I assume you have the wet mount system. Throw away the neg holders (just kidding) and dry mount them directly on the wet mount holder.
I don't mean to be so off topic here, sorry.
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