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Old Oct 3, 2003, 6:58 AM   #11
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Quote:
Originally Posted by RobJK
Altaman:

What "spray" do you use on your prints, and where do you get it?
It is called Inkjet Fix, it has UV inhibitors. I have had no fading prints yet (could be too soon to tell how good it is working).
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Old Oct 3, 2003, 10:48 AM   #12
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RobJk

Thanks for the information. That is good news to hear and goes a long way towards making me wonder if perhaps the i960 is the better choice (given its clear speed advantage). I understand the i960 is now available (at least online) and hope to be able to take a look at it and compare color photo quality with the HP 7960.

If anyone has already done this, I would appreciate any feedback.

Thanks again.
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Old Oct 3, 2003, 6:48 PM   #13
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At photo_i.uk.com there is a review of the i950 and the HP7960. I expect the i960 to be the same as the i950, but Steve here says its FASTER which is amazing.

At photo-i, there is some color comaprison in the review. It seems to me that the HP is more accurate (EG the color cotton reels). I've tested Vincent's test print with my i950 and yes indeed, that last cotton reel on the right goes very dark, whereas the HP keeps it the original color. Note however the blue eyes of the baby: my i950 doesn't add this blue at all so I'm not sure what Vincent's problem was.

For me, the color accuracy was a let down. The blacks are also not as deep as Epson. So I've had my eye on the HP since the review, but it is interesting how nice the speed factor is. I find with slow printers I tend not to be bothered, whereas I'm almost itching to keep using the i950 because it's so fast.

I'm about to try different papers to test the fade factor. It would be at least 4 months before I can tell though!
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Old Nov 11, 2003, 8:51 PM   #14
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I've just run some tests on the HP line and the Canon i900D and i470D and i475D, using the photo-i test file moved to a card.

I used an Epson glossy paper, which worked well in all of them.

The HP 7960 was set up with a 56 cart instead of 59, which meant it was doing PhotoRET IV, not PhotoRET Pro.

As PhotoRet IV, the 7960, 7760, and 7660 gave similar results. However, I find that issues like color casts vary from printer to printer - I used two different 7660s with the same paper and got a different color cast - not objectionable, but different. I have no explanation for this. The first 7660 I tested gave the best color accuracy of any printer I tested, very similar to Photo-i results or the 7960 running PhotoRET Pro

The Canons gave similar results to each other as to color, as reported in Photo-i reviews - skin reddish, eyes and other grays on the blue side. The 470 using the PPP paper setting gave more accurate color than any other Canon printer tested, second only to the first HP 7660. Again, I think this is printer-to-printer (or perhaps cartridge-to-cartridge) variation, as the 475 is essentially the same printer as the 470.

Comparing the Canons to the HPs, using 1200 DPI scans, the drop size issues become evident. Excluding for a moment the 4-color 470 and 475, the Canon 900D was obviously sharper in 1:1 views of the 1200 DPI scans, and it is likely due to the drop size. Comparing items side by side with the naked eye, the Canon 900D looks a bit sharper than the HPs if you are looking closely in areas where resolution issues are obvious.

The 470 and 475 turned in creditible performances on all counts, but they are 4 color printers, and they dither more than the others.

All the printers turned in excellent prints when viewed by the naked eye. While less sharp, the HPs in no way drew attention to that point - it's only in direct critical comparison that the issue shows up.

I have a concern that affects both brands. The white spool blows out the highlights, or appears to. A moment's though shows that to be an incorrect analysis - the original has decent blue-gray shadow detail to begin with, and we are not dealing with a light-based process like chemical printing. There is no process involved in inkjet printing that can blow out the highlights. I seriously doubt that exceeding the gamut is involved - it's a mid tone blue gray that is missing here, the shadows of the white threads on each other. Delving into the bit level on a few of the prints (I've just done all this yesterday) shows that the 4 color printers (Canon 470 and 475) do a good job on the white spool, with just a few scattered dots for the blue-gray shadows. An Epson 925, casually tested, did similarly. However, the Canon 900D and 2 of the HPs (all I've looked at so far) are putting down a yellowish color in the shadows instead of a blue-gray. This feels like it may be a bug in the printers' sharpening algorithm. It may also be the reason for the dull performance in the red spool detail for the HP and high end Canon. Don't forget, there is a hefty little computer in there, and computer programs got bugs...

More on this when I have the time to review tests in detail. If you've run your own with this file, do a scan at 1200 and magnify to 4:1 to see the yellow dots. Go to negative color, and they are easier to spot as blue dots against a black background.
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Old Nov 12, 2003, 3:01 AM   #15
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I did further examination of the white spool, scanning at 1600 DPI.

At 1200, at high magnification, the ink dots are not really resolved, but at 1600 they very nearly are.

What I believe I'm seeing are almost uniform distributions of yellow, cyan, and magenta dots - hardly surprising for the white spool. On a 6 color printer, those dots are cmY, as there is no "y", that is, no "light yellow", but on a 4 color printer, we have CMY, with no light colors of any kind.

What I initially thought (from observation) was a blue-gray in the shadows of the original is by actual measurement closer to a purple-gray, with some blue and some magenta.

At 1200 DPI, the more intense full yellow stands out compared to the light magenta and light cyan of the 6 color printer, and it looks like yellow dots on a vaguely pastel background. But at 1600 dpi, it's clearer that it's meant to be a more nearly uniform distribution of dots. And with a 4 color printer, the intensities are more nearly equal at any resolution.

On the six color printers, with the delicate shadows of the white spool, it may be that the greater intensity of the yellow is countering the blue componentof the shadows, weakening overall shadow definition.

Presumably, on a 4 color printer, the more even intensity of the CMY dots preserves the shadow better. At least, that's the best theory I've come up with so far...
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