filmscanners: SS4000 options
With that incredible offer at ecost I too have one of the 80 SS4000s that will arrive on Sept 15 on order. I have been looking at the SS4000 for a long time but could never understand what the slide and strip options are. Are these "trays" not included with a basic unit or are they really options or spare or what? Thanks -- Stephen N. Kogge [EMAIL PROTECTED] http://www.uimage.com
Re: filmscanners: Link to Nikon 8000 banding example...
> > Just a thought. Do you get stop/start motion of the film carrier > > because of > > spooling, during the actual scanning process? > > I understand your point, but...the scanner stops for every line anyway, it > has to...it's just a matter of how long it stops, so providing there isn't > some some race condition that this long stopping exacerbates, the stopping > "should", mechanically, not make any difference. > > But does the head actually stop or like a lot of flatbeds scan "on the fly" with CCD's you can define how long to sample - think of it as an electronic interrupter shutter - motion artifacts will not be seen if the relative motion is low wrt the time the CCD is sampling this could be as long as a ?? millisecond ??? There are usually no mechanical shutters with video and still CCD cameras and they work with motion :-) Anyone who has ever used a lathe knows you really want to do the work in one pass - if/when you stop the backlash in the gears may not register back to where you left off. There is nothing to say you need to wait for the stepper to stop just that it "ought" to have moved to the next spot. Disks now use linear actuators and optical encoders, stepper motors have a long settle time and the gears a backlash. This "banding" could be the visible backlash as the CCD head gets back up to speed and is at the wrong place after a pause to dump the buffer or the remote system to flush its buffers. -- Stephen N. Kogge [EMAIL PROTECTED] http://www.uimage.com
Re: filmscanners: My replacement 8000 is banding like the first one :-(
Re the "banding problem" My first reaction was that the scan is being done "off" a native resolution 4000 dpi, 2000 dpi, 1333.333 dpi, 1000dpi etc and that software interpolation was/is being done. After a few of the other comments about possible mechanical problems I remember watching either my AT210 (flatbed) or an HP doing it's "scan dance" where it scans forward, pauses while the programed IO SCSI interface dumps the scan buffer, backs up past the backlash of the gears then scans forward for another chunk. A lot of the early scanners had poor SCSI performance. Does the scanner seem to stop and start or is it a smooth scan? An analogy is with many SCSI tapes that are "streamers". As long as you keep them fed with data they will keep writing (or reading) if data stops the drive writes a "stretch mark" hoping to see more data soon, if no write data is provided the drive stops, when you write again the drive has to back up past the last data then read past the erased area where it starts the next block. The stops and starts waste tape and slow down the drive, we solved that back in the late 80's with the BSD dump routines and multiple write and read buffers and proceses. So is it possible that your scanner is out running your system, the scanner stops and has to back up. It could also be a similar problem that the data rate from the CCD head is higher than what the Scanner interface can handle and the microcode/firmware in the scanner is doing the "back up and scan a swath" dance. -- Stephen N. Kogge [EMAIL PROTECTED] http://www.uimage.com
