Hi Ben,
Thanks for the info. Perhaps you didn’t read my entire post? I do have a
spectrophotometer (Xrite SP62). The problem is I can’t use it for everything
because some of the things I’m trying to measure are just too small for the
aperture. For example if you want to measured colours in a printed book or even
the Wolf Faust IT8 target itself you just can’t...
Cheers,
Zi
On Jun 11, 2015, at 11:58 PM, Ben Goren <ben@xxxxxxxxxxxxxxxx> wrote:
On Jun 11, 2015, at 7:52 AM, Zi Wang <ziwang84@xxxxxxxxx> wrote:
I’m quite literally trying to calibrate a scanner so I can pretend it’s a
colorimeter because my samples do not have homogeneous surfaces that are
large enough for a proper spectrophotometer.
I doubt you're going to have much luck with a scanner for this
purpose...building a profile for a scanner that's good enough for that is
going to be an extreme challenge.
I'm hoping I'm closer to the end than the beginning of building a camera
profile that would suffice...and some of the gear I'm building for that
should, in theory, more than suffice. But it's still very much a work in
progress.
A key piece is that it's possible to build a large, high-quality spectroscope
on a very small budget with the sorts of things you'd find at an arts and
crafts hobby store. My latest design iteration was close, but I didn't mount
the (cheap plastic film) diffraction grating very well, and there's more
stray light that I can eliminate.
I'll be using the spectroscope and some other similar low-budget high-quality
gear to build a camera profile that should be good enough for what you're
looking for. At least the early designs will still need a spectrometer (like
an i1 Pro) and a traditional chart to provide a calibration reference, though
I'm pretty sure even that much can be done away with...and that the same or a
similar hardware setup can probably be adapted for high-resolution
high-precision spectroscopy work. Again, just with a digital camera (that can
output RAW) and some cheap DIY craft-type equipment.
...but I'm still not quite there yet. If the gods smile on me, I'll have the
spectroscope done this weekend, maybe sooner...but I've still got a fair
amount of the rest of it to put together....
Cheers,
b&
