Trident 4
Trident 4
- Subject: Trident 4
- From: neilB <email@hidden>
- Date: Wed, 22 Nov 2000 00:56:32 +0000
Guys
Anyone else out there having trouble profiling a scanner with Howtek's Trident 4 ?
I was hoping to profile the modern way - allowing image edits in the SW whilst viewing a profile compensated screen. And to subsequently enable output to a chosen workingspace with those operator edits and the profile to profile conversion concatenated into one 16 bit correction process, also with the facility to output at 16 bit. Trident 4 appears able to do all this on reading the manual.
We at first made an IT8 scan using the inbuilt input profile ICC procedure but unfortunately the resulting IT8 scan is much too dark with a histogram which is concentrated into the shadow end abutting the histogram's limits - and this scan results in a high deltaE [max. over 5] and an unusable profile from IPB.
So - we made an IT8 scan, setting the black and white endpoints and with a linear tone and cast "curve" at the default 2.75 density, and ran Kodak IPB 4. The resulting profile works great in a Photoshop profile to profile [on the IT8 scan], giving an almost perfect IT8.
In Trident there is a useful facility called RGB blowback which uses the selected input and monitor profiles to display the scanner image so that an operator can expect continuity between Trident and Photoshop.
Without profiles loaded the IT8 screen image is quite pink, I guess that signifies that the hardware is a bit high on the red channel. When we select the input and monitor profiles all seems well, as the display now looks neutral, until we measure a middle gray [block 11 on the IT8] which now measures 138/118/110. This makes it impossible to use the numbers to work on a scan when optimising the image.
Opening the image in Ps 6 and assigning the Trident profile to it gives a similar reading so I surmise that Trident is actually treating the data as if it is actually in the scanner workingspace for the purpose of displaying the colour numbers.
I've not seen this before.
If we scan the IT8 with full cast correction [using cast corrected black and white eyedroppers and including the useful mid tone eyedropper] and run a profile from that IT8 scan then the numbers are right in Trident but, all subsequent scans must now be cast corrected for the profile to work [not so good if you're scanning a sunset with no neutrals in it??].
I didn't expect to have to do this but am I wrong?
If I want to use cast correction in the scanner SW should I expect to have to use it when scanning the IT8? I guess that just means making two profiles which we have done as a workaround.
Of course we save the IT8 scan settings we used when making each profile for use as a staring point on subsequent scans.
Secondly,
Trident 4's "Export to Workingspace" option seems to have a very strange effect on the monitor image if it is checked, even with no output space selected in Trident's Colorsync dialogue. The monitor shows an extremely dark image and the scan is very dark too. On an IT8 the last 5 or so dark patches are all at 0/0/0. Unfortunately this option seems to be broken which means a time consuming and potentially data destructive profile to profile into Photoshop.
I just can't work out where the Trident SW is getting the workingspace destination from when we have none selected in Trident's Colorsync screen. Alterations to the "input" field in the Colorsync 3.01 CP do not seem to alter the screen appearance.
anyone else seen this, or have any comments please?
neil
Neil Barstow
phone: 44 (0) 1273 774 704 fax: 44 (0) 1273 323 454
mobile: 44 (0) 77 78 16 02 01