Larry, it is most likely a cause of bad DC motor bearings. I have a new motor - I just haven't replaced it yet because I never scan over 4000 DPI.
Pali
Larry, it is most likely a cause of bad DC motor bearings. I have a new motor - I just haven't replaced it yet because I never scan over 4000 DPI.
Pali
Pali, thanks. I did a quick search and see mention of a Maxon 285787 motor. Is that the one? Where did you get the motor and what was the cost? It's not to the point I need to replace it yet for large format, but for 6x7 and smaller I generally scan at the max resolution on the 5000. Getting rid of the jaggies would be nice.
Looks like around $370. https://www.maxonmotorusa.com/maxon/...re/re35/285787
Larry, I got mine from ABC-Scan before they closed a few months ago. Maxon 285787 is not the stock version but it was speculated that it might work but polarity may need to be changed. The original is 143202.
Also bearings may be simply replaced for a perfect fix, I'd say that the bearings inside a maxon are pretty standard in a skf/fag catalog.
Maxon installs bearings for +20,000 hours service for rated specs without inbalance. It is a surprise if bearings inside a maxon fail, if not a bad design of the assembly. I've played a bit with maxons and found they are top Q.
Pere the only reason why I say this is bad bearings is because it is a known issue. The Scanmate service manual itself notes that it is due to bad bearings in the DC motor and recommends replacing the motor as a fix. I know some people who replaced and saw significant improvements. The motor is fully enclosed but I am sure there is some tricks to get it to open and replace bearings but might not be worth the effort. I paid $150 EUR for mine but the company I bought it from is no longer in service.
A known issue is a known issue. Anyway it would be interesting to measure the axial play of the replaced motor, to know what play caused the problem, specs (new) are 0.025mm. These are preloaded type bearings to provide a degree of stiffness...
Last edited by Pere Casals; 22-Jan-2019 at 08:16.
Adding my 2 cents.
I scanned the loaned Edmund Optics 2X2" glass 1951 USAF target various ways on a V700. No wet mounts.
Using V700 OE 8X10 film guide with target flat on dry platten. 5.2
Same as above but sitting on TOP of my 8X10 AN glass. I often USED to scan this way. 5.2 but wavy.
The target installed in 35mm slide mount on the V700 OE slide multi multi holder at OE height. 5.4
Good enough for me. I am not posting images.
YMMV
Tin Can
Randy, with the area guide and scanning on bed the Low Resolution lens is used, having lower performance but covering the entire bed. When scanner detects a film holder then the High Resolution lens is used, having a superior performance but covering only 5.9" wide, wich is also a large coverage capable for even 5x7" film, if having that holder.
Even with the low performance lens with 8x10 you obtain and equivalent 320MPix effective scan, wich is an insane ammount of effective pixels... for 4x5 better to use the holders, if the shots are sharp and wanting a big print.
Pere, I know that and use the 4X5 2 up OE holder, the V700 does work best for 4X5. And gives me my best LF scans, but I also shoot 5X7 up to 11X14 and must settle for the lower res.
I don't scan anything smaller, well i do but simply to file away. Evidence...
The V700 also 'sees' the large notch in the 8X10 mask area for some reason and always uses the low rez lens for the 8x10 films, just as it does for paper scans. Normal.
I don't print from my scans, i file them. I print optical.
It seems the low rez and high rez lens capture is not that different, according to my results on my 5 year old V700. Read that twice.
Tin Can
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