Scanning oversized objects

  • Thread starter Thread starter Josh A.
  • Start date Start date
J

Josh A.

There was a thread a couple of years ago by a guy who was scanning and
stitching album covers with an HP4600 and getting light/dark banding
showing up in the scanned images:

http://groups.google.com/group/comp.periphs.scanners/msg/8f43fb3c83fae1e5?hl=en

His problem may have been resolved by using Vuescan instead of HP's
supplied software. I've tried using Vuescan with my HP4600, too, but
am still getting the banding issue. My question is, are there any
other low-priced scanners out there similar to the HP4600 and HP4670?
That is, with a removable platen lid and with no lip surrounding the
scanning surface so that an oversized object can be laid directly
against the glass? TIA
 
There was a thread a couple of years ago by a guy who was scanning and
stitching album covers with an HP4600 and getting light/dark banding
showing up in the scanned images:

http://groups.google.com/group/comp.periphs.scanners/msg/8f43fb3c83fa...

His problem may have been resolved by using Vuescan instead of HP's
supplied software.  I've tried using Vuescan with my HP4600, too, but
am still getting the banding issue.  My question is, are there any
other low-priced scanners out there similar to the HP4600 and HP4670?
That is, with a removable platen lid and with no lip surrounding the
scanning surface so that an oversized object can be laid directly
against the glass?  TIA
Click to expand...

One of the problems with scanning oversized objets is the the scan
surface is slightly recessed from the edge of the scanner not allowing
an oversized object to be flat. Best thing to do is to overlap the
scans as much as possible. If the piece to be scanned is too rigid it
may not be possible especially if there is a dram tic drop. My Epson
V700 would be lousy as there is almost a 1/4 inch drop from the edge
of the scanner case to the scanning glass.

Tom
 
I have a parallel question to ask. Has anyone used a digital camera to
do similar 'scanning'? I would think placing the camera as far as
possible from the object, yet filling the field of view by optical
zooming should get the foreshorting minimized. How do you light the
subject well enough? Glare has been my issue.

Thanks,

Tim.
 
One of the problems with scanning oversized objets is the the scan
surface is slightly recessed from the edge of the scanner not allowing
an oversized object to be flat.
Click to expand...


Again, that's the advantage of the HP4600 because there is no raised
edge next to the scanning surface. However, the banding that shows up
on scanned images using a HP4600 is a dealbreaker for me, so I'm
hoping to find a different model that has the pro without the con.
 
I have a parallel question to ask. Has anyone used a digital camera to
do similar 'scanning'? I would think placing the camera as far as
possible from the object, yet filling the field of view by optical
zooming should get the foreshorting minimized. How do you light the
subject well enough? Glare has been my issue.

Thanks,

Tim.
Click to expand...

Tim,

A "good" digital camera should work fine.

Proper lighting is two (equal) lights placed on either side so that
they shine down on the copy at a 45 deg angle. Have the camera
directly above the item to be copied. and make sure the lights are far
enough away so that they cast an even light on the object.

It's best to NOT use flash. If flash is the only option, it must be
off-camera (not available with most consumer digital cameras) and
again, at that 45 deg angle to the item to be copied.

Regular incandescent lights should be fine, but you might have to do a
bit of color correction of the image.
 
Charlie Hoffpauir said:
Regular incandescent lights should be fine, but you might
have to do a bit of color correction of the image.
Click to expand...

Shoot a custom white balance and you may not even
need to do that.

For the LP jackets mentioned in the basenote, 200 dpi,
arguably "photo quality" is a mere 6 Megapixels. Even a
cheap digicam can do that these days.

I was shooting LP covers for eBay listings a few years
ago, using a copy stand someone had thrown in the
trash, and slant CFL lighting. A simple Action script
in PhotoShop sufficed to remove slight barrel distortion.
No stitching at all, and rarely any other type of edits, as
the exposure was worked up against an 18% gray
background which also had the corner alignment marks.

Digital cameras, whether DSLR or digicams, can make
great "scanners" for larger objects.
 
Charlie said:
Tim,

A "good" digital camera should work fine.

Proper lighting is two (equal) lights placed on either side so that
they shine down on the copy at a 45 deg angle. Have the camera
directly above the item to be copied. and make sure the lights are far
enough away so that they cast an even light on the object.
Click to expand...

Am alternative is to do the job outdoors on a bright but overcast day -
that gives a lovely diffuse light. But this will only work it you can
get far enough away with the camera that you are not blocking the light.
It will also reduce or eliminate the need to do colour correction on the
results. I have also taken photos right by a north-facing window using
daylight as the illumination with good results.
 
I have a parallel question to ask.  Has anyone used a digital camera to
do similar 'scanning'?  I would think placing the camera as far as
possible from the object, yet filling the field of view by optical
zooming should get the foreshorting minimized.  How do you light the
subject well enough?  Glare has been my issue.

Thanks,

Tim.
Click to expand...

You can do this with a camera, the only problem is you get a
relatively small image. If you are scanning an 11x17 piece you should
get a 60mb or so image at 300ppi with a scanner. Only the top end DSLR
can do a 20MP image. If you are reproducing a piece for the web a DSLR
is fine. The best lens to use is a 50-60mm macro to maintain a flat
field, a 35mm macro would work on an APS sensor. While photographing
in open sunlight or open shade works, be sure you are using the
correct color balance. Getting the image squarely in the frame is very
difficult this way. Best way to photograph art work is inside on a
copystand for small pieces or using a tripod on larger pieces. 3200
1000W Lowell Totalights are a good light source, use 2 at 45 degrees
on either side of the art work for even illumination. If the work is
glossy or reflective use polarizing filters on the lights and camera.
If you plan to do this a lot invest in the Kodak book on copying art
work.

Tom
 
Check your math. 300 dpi (ppi, whatever) is 90,000 pixels per square
inch. an 8.5" x 11" page at 300 dpi is about 8 megapixels. Most modern
digital cameras can do that.

THAT SAID, HOWEVER: It just never works well. The quality is just
crap. Always. Period. A digital camera is no substitute for a scanner.
 
Check your math.  300 dpi (ppi, whatever) is 90,000 pixels per square
inch.  an 8.5" x 11" page at 300 dpi is about 8 megapixels.  Most modern
digital cameras can do that.

THAT SAID, HOWEVER:  It just never works well.  The quality is just
crap.  Always.  Period.  A digital camera is no substitute for a scanner.
Click to expand...

Do the copy work right and it will be close to a scanner. Have done
thousands on slides and digital, just have to have the right
equipment. A scanner maybe slightly better but it is close, and if the
piece is larger than the scanning bed photography maybe better.
The OP was talking about oversized so I picked 11x17 an 8.5x11 is
approximately 30mb so more like 10mp, 8x10 is 24mb or 8mp. So 11x17 is
20mp.

Tom
 
If the oversize object is a Record Album Cover, there are low priced A3
Scanners that will scan 11.7 X 16.5 inches.

Check out the A3 USB 1200 Pro Scanner
http://www.mustek.com/index.php?pag...r_id=0&option=com_virtuemart&Itemid=&vmcchk=1


Buy here in the USA.
http://www.newegg.com/Product/Product.aspx?Item=N82E16838135002

--
CSM1
http://www.carlmcmillan.com
--
Check your math. 300 dpi (ppi, whatever) is 90,000 pixels per square
inch. an 8.5" x 11" page at 300 dpi is about 8 megapixels. Most modern
digital cameras can do that.

THAT SAID, HOWEVER: It just never works well. The quality is just
crap. Always. Period. A digital camera is no substitute for a scanner.
Click to expand...

Do the copy work right and it will be close to a scanner. Have done
thousands on slides and digital, just have to have the right
equipment. A scanner maybe slightly better but it is close, and if the
piece is larger than the scanning bed photography maybe better.
The OP was talking about oversized so I picked 11x17 an 8.5x11 is
approximately 30mb so more like 10mp, 8x10 is 24mb or 8mp. So 11x17 is
20mp.

Tom
 
I have one of those. It does work, but it's a very poor scanner with
very poor software.
 
Nigel Feltham said:
Thanks for the info, must remember this one next time I do a colour scan
over A4 width (not so critical for mono or greyscale scans) - I guess the
2
edges will also have slight colour differences as well as the brightness
difference (colour temperature varies with bulb temperature, reason
scanners wait for bulb to warm before first scan to attempt to minimise
things but nothing can get it spot on).

I guess using a camera with copy stand would have the same problem as
impossible to light the document evenly with only 1 bulb or precisely
match
2+ bulbs.
Click to expand...

It depends on the size of the document you copy with a copy stand.
If the document is a large one, you use more lights. Some copy stands have
four lights.
 
Thanks for the info, must remember this one next time I do a colour scan
over A4 width (not so critical for mono or greyscale scans) - I guess the2
edges will also have slight colour differences as well as the brightness
difference (colour temperature varies with bulb temperature, reason
scanners wait for bulb to warm before first scan to attempt to minimise
things but nothing can get it spot on).

I guess using a camera with copy stand would have the same problem as
impossible to light the document evenly with only 1 bulb or precisely match
2+ bulbs.

I guess the only scanner that could possibly have totally even scans is an
LED based film scanner like the NIKON ones as these use just 1 LED of each
colour and spread the beam using lenses due to the small area being scanned
(LED flatbeds have a line of LED's so brightness could still vary between
the individual LED's, CFL film scanners) but I guess even these could
suffer from uneven output across the CCD sensor.
Click to expand...

Getting 2 lights becomes much easier with digital. Just go to a
hardware store and buy 2 work lights, about $20, by getting 2 at the
same time they will be new, halogen (longer life and longer
maintaining color temp) and shouldn't be a problem.

Tom
 
rjn said:
Shoot a custom white balance and you may not even
need to do that.

For the LP jackets mentioned in the basenote, 200 dpi,
arguably "photo quality" is a mere 6 Megapixels. Even a
cheap digicam can do that these days.

I was shooting LP covers for eBay listings a few years
ago, using a copy stand someone had thrown in the
trash, and slant CFL lighting. A simple Action script
in PhotoShop sufficed to remove slight barrel distortion.
No stitching at all, and rarely any other type of edits, as
the exposure was worked up against an 18% gray
background which also had the corner alignment marks.

Digital cameras, whether DSLR or digicams, can make
great "scanners" for larger objects.
Click to expand...


Or wiat for a bright, overcast day. A clouded sky, as long as you make
sure that you don't pick up a reflection from the surface of what you are
scanning, is like a giant soft light.

The most important thing is to get your camera square with the subject so
you don't have keystoning (generally centered on the center of the subject
on a tripod, and the subject stright up and down or at a matching angle.

Brendan
 
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