Mike Chaney's Tech Corner

Mike's Software => Qimage => Topic started by: martyan on March 03, 2023, 07:36:14 PM



Title: Overdrive not working in Qimage One
Post by: martyan on March 03, 2023, 07:36:14 PM
Hi!

I just purchased Qimage after using the demo version first. I need it to make 1200 ppi prints with my Canon Pixma Pro-200. I'm printing lenticular 3D images, that's why I need the highest output resolution possible.

I have a problem - already had with the demo version. Sometimes the overdrive works, sometimes it doesn't, and I just get 600 ppi. I've tried tweaking the settings, tried clearing up memory, but right now nothing seems to work.

When printing for 50 lpi lenticular sheet, I should get 24 images with 1200 ppi, but I only get 12 (12 x 50 = 600). What should I do to fix this?

Thanks!


Title: Re: Overdrive not working in Qimage One
Post by: admin on March 03, 2023, 09:25:02 PM
Overdrive is a Qimage Ultimate feature that allows you to send data to the driver at twice the driver's native PPI.  It is not available in Qimage One.

Some of the Canon drivers allow you to enable 1200 PPI directly in the driver.  Sometimes you have to click "Print Options" from the Page Setup tab of the driver and set "Prevention of Print Data Loss" to "Off" to be able to get the driver to actually run at 1200 PPI.  It doesn't look like the Pro-200 driver offers that option even though you can do it on the Pro-100.

Have you tried printing 24 images on your lenticular sheet?  Qimage will allow you to print as many images as you like no matter what resolution so it's not like you can't print 24 images.  You can print them and I doubt there would be a significant difference because the printer cannot produce 1200 PPI full color images anyway.  Meaning, at a high enough magnification to be able to see 600 vs 1200 PPI, you are going to see ink dots.

And a final option is, if your images are high enough resolution, you could always turn interpolation "off".  That will send the images at full resolution.

Regards,
Mike


Title: Re: Overdrive not working in Qimage One
Post by: admin on March 03, 2023, 09:41:50 PM
Scratch that.  I remembered we did add the "Overdrive" option in Qimage One but it is an optional setting: choose Edit, Preferences, Show Advanced Resolution Settings, and turn it "on".

Regards,
Mike


Title: Re: Overdrive not working in Qimage One
Post by: martyan on March 04, 2023, 11:17:55 AM
Thanks for your reply.
As I said, I already succesfully printed 1200 ppi images with the Qimage demo version, using the overdrive setting. Surely it should work with the licenced version then!
Sometimes it worked, sometimes it didn't and the only explanation I could think of was that it was a memory issue.

Now I tried loading the image from hard drive instead of using the Photoshop plugin. No difference, I just get 12 images. Pro-200 is a terrific printer and on glossy paper it makes a big difference whether it's 1200 ppi or 600 ppi. On 30 lpi sheet I was actually able to get a whopping 40 images and in the finished 3D picture I was able even count them all (objects that "hover" very var from the surface, so the difference between each image is noticeable).

I'm testing this with a very small images, so now it's definitely not about shortage of memory either. So any ideas what to try next?

Scratch that.  I remembered we did add the "Overdrive" option in Qimage One but it is an optional setting: choose Edit, Preferences, Show Advanced Resolution Settings, and turn it "on".

Regards,
Mike


Title: Re: Overdrive not working in Qimage One
Post by: martyan on March 04, 2023, 11:21:50 AM
I don't understand what you mean by this. Surely Qimage doesn't have the option to interlace 24 separate images into a lenticular print? I've made lenticular 3D since 2000 and always used photoshop for the interlacing (for example 24 images interlaced with 1200 ppi means 24 lines per each lenticule on a 50 lpi lenticular sheet).

Oh and one more thing that might help to sort out the problem: Although I only get a 600 ppi print with overdrive (1200 ppi), it's clearly sharper than with the 600 ppi setting. It seems it's an INPUT issue - Qimage outputs 1200 ppi but doesn't read the image in full resolution.


Have you tried printing 24 images on your lenticular sheet?  Qimage will allow you to print as many images as you like no matter what resolution so it's not like you can't print 24 images.  You can print them and I doubt there would be a significant difference because the printer cannot produce 1200 PPI full color images anyway.  Meaning, at a high enough magnification to be able to see 600 vs 1200 PPI, you are going to see ink dots.



Title: Re: Overdrive not working in Qimage One
Post by: admin on March 04, 2023, 12:40:22 PM
You have some odd assumptions that are just not true so I'm going to need to know more about the specifics.  Printers only care about input resolution and final print size.  You have an image with a certain resolution (doesn't matter what it is) and you want to print that image at a certain size (doesn't matter what that is).  Qimage can take any image and print it at any size you select so it is not true that Qimage "can't print" at the size you need: it can print any image at any size and it can put 24 images on any size media.

Now let's talk about resolution.  In your last example, you say 1200 PPI means 24 lines per each lenticule on a 50 lpi sheet.  So that's simply 12 lines per lenticule at 600 PPI: but Qimage can still print the 24 images at the same size as it did at 1200 PPI.

Now let's look at my example.  You have 24 images that are 1200x1200 resolution and you intend to print them at 1x1 inch on a 6x4 inch lenticular sheet (borderless).  So you add each image at a size of 1x1 inch and you get 6x4=24 images.  It makes no difference whether you have Qimage set to 300, 600, or 1200 PPI: there will be 24 images on that 6x4 sheet no matter what resolution you choose.

With that said, if you select "Overdrive 1200 PPI" in Qimage, it will send 1200 PPI to the driver.  There is no path where Qimage can not read the full resolution: it's job is to take all the pixels in the image and spread them out to whatever print size you choose.  Each of your 24 images prints at a specific size: set that size when you add the 24 images and make sure the resolution says "Overdrive 1200 PPI" and Qimage will send those images at 1200 PPI regardless of image resolution.

So let's get to the real meat here.  You haven't discussed what really matters when doing any printing (regular or lenticular printing): what is the resolution of the images you are printing and what is the print size for each of your 24 images?

Mike


Title: Re: Overdrive not working in Qimage One
Post by: martyan on March 05, 2023, 10:17:40 AM
Thanks for sharing those things, Mike. Have you done any lenticular printing? I have to ask, because it's very few people who do it or even know how it works. Being a graphics professional for more than 20 years, I consider myself pretty knowledgeable when it comes to printers, resolutions and particularly lenticular printing. Please trust me on this and let's not waste energy talking what resolution means but just find out how to make things work :)

Just to make sure we know what we are talking about: When I say I have 24 frames on a lenticular 3D picture, it doesn't mean I want to print 24 separate images. All of those 24 images are interlaced into one SINGLE image that is 1200 ppi in resolution. Every 24th vertical line belongs to the first frame, the next line to the second frame etc. In your example you seem to assume I need to print 24 separate 1x1 inch images on a 6x4 inch sheet. This is not how lenticular works, a 24 frame lenticular image is 24 images interlaced into a single print. The output size plays absolutely no role here, only the resolution.

So in terms of printing with Qimage, I need to print ONE 1200 ppi image and I need to get each pixel on the paper. It is the magic of the lenticular material that it magnifies each of those 24 lines and then you see a different image from different angle.

And I know Qimage demo version was able to make this happen, I assure you, but now it does not happen with the version I purchased. It also stopped happening a couple of days before the demo expired. And I need to sort out why that is. Because the possibility to get 1200 ppi prints was the only reason why I need Qimage and I trust there is a way to configure it in a way that it does that consistently - not just for me but other users as well.

What happens now is that the image prints clearly sharper when I use overdrive compared to not using it. However, it still outputs only 600 ppi from a 1200 ppi image file. This  means, it loses half of the image data somewhere along the line. This is not an odd assumption, just a factual observation.

I attach an image file where on the left you see the original and on the right the Qimage print. These are not in 100% resolution but it's not necessary, because this effectively shows what you can see with your eyes (you can't see individual pixels in a 1200 ppi print anyway): In the original image there are 24 images spread over a distance and you can't distinguish them from one another (or just slightly, where I've marked the numbers.

Now one way to find out what do do about this situation: I can send you the original file (which is a small detail of a much larger image - file too large to attach here), then you can print it out in the overdrive mode and you will instantly see whether you get the smooth transition (the left image) or the stepped 12 images. In the first case scenario we will know we have some differences in the Qimage settings or our computer setup and we will find this out. In the second case it means the overdrive feature is not working the way it should and it needs to be fixed.


Title: Re: Overdrive not working in Qimage One
Post by: admin on March 05, 2023, 01:33:22 PM
I was afraid this would happen: all that explanation and you still didn't answer my question.  I need to know the resolution of the original image and the final print size.  And I don't mean 1200 PPI.  What is the pixel resolution of the original image you are printing (X and Y pixel dimensions) and the final size you are printing with Qimage?

I have done some lenticular printing but it was about 15 year ago.  Still have some sheets here.  Up until now, you've been talking about putting 24 "images" onto one lenticular sheet.  I didn't take that to mean you have a 24 frame lenticular image but now I see what you meant once you specified 24 frame.  I've seen people print small lenticular stickers, large lenticulars, etc. and I had no idea what you are doing because so far you are asking us technical questions without any information on how you are actually using Qimage.  But the bottom line is the same.  Qimage could not care less what is in the image you print: it takes the pixels in the original image and spreads them out so they fit in 1200 PPI (if you are using Overdrive 1200).  Period.  Qimage has no other job.  So in Qimage, you are taking an image of unknown pixel dimensions and printing it at an unknown print size.  I'd like to know those values because those two values are the only ones that matter (along with your overdrive 1200 selection).

So if you have ANY image and you print it at 8x10 with overdrive 1200 selected, Qimage will send the driver 9600 x 12000 pixels and tell the driver to print that in a size of 8x10.  I don't care if every pixel in that 9600 x 12000 image is black or there are 24 alternating frames in that image: it is printed the same.  If you prepare your lenticulars correctly at your desired 1200 PPI, an image intended for 8x10 will have 9600 x 12000 pixels so if you use overdrive 1200, the output resolution matches the input and Qimage does no interpolation (none is needed because the pixels all align).  But if your original is 4800 x 6000, Qimage is still going to send 1200 PPI (9600 x 12000) to the driver for an 8x10: 75% of the pixels will just be interpolated.

I think you've already found out the problem is not Qimage.  You say the demo worked and then all of a sudden didn't work (even before you got the registered version: which prints the same BTW).  So that means you have a problem outside of Qimage.  Per my examples, I can tell you one thing for sure and this is the bottom line: if you have Overdrive 1200 PPI selected in Qimage, Qimage will send 1200 PPI to the driver.  Now there could be other problems here which is why I asked for the specifics (image resolution and print size).  One other problem could be that the Pro-200 driver always runs at 600 PPI internally.  There is no way around that.  So Qimage can send 1200 PPI to that driver but there is no guarantee that the driver won't immediately step it down to 600 PPI internally because it doesn't have a 1200 PPI native mode like the Pro-100.  I don't have a Pro-200 so I can't check physical output.  Lastly, you cannot get 1200 PPI of information on any media with any printer whether the driver supports it or not.  The media cannot handle it and neither can the printer hardware.  If you are doing something that truly relies on 1200 PPI resolution, you are going to be disappointed because no inkjet photo printer can exceed about 800 PPI of actual detail with any scrutiny.  At 1200 PPI, you can only fit 4 printer dots of one primary color into each lenticular frame line.  That is far fewer than needed to make a full color "pixel".

And if you print in landscape mode, the printer can only lay 2 dots per line.  Have you considered that?  The Pro-200 is 4800x2400 so if you print a lenticular portrait and then print one landscape, the landscape print will be half the resolution in the X direction.

Anyway, if you hold your mouse over the thumbnail of the image you intend to print, it'll show you the resolution on the bottom EXIF bar in Qimage: then you'll know how many pixels Qimage sees in the original.  We need that... and the print size you are choosing.

Mike


Title: Re: Overdrive not working in Qimage One
Post by: admin on March 05, 2023, 01:59:42 PM
And one more thing.  I assume you've turned sharpening "off".  It is important that you don't try to sharpen a lenticular image.

Mike


Title: Re: Overdrive not working in Qimage One
Post by: martyan on March 05, 2023, 06:30:27 PM
Okay, maybe we're getting somewhere. I must say I don't understand what's the relevance of the image dimension because this is a general issue regardless of the printed image size. For example, now I've printed different sized details of the same image and the same info always applies.

But okay, let's take the test image I last used: Pixel dimensions 2016 x 2018, resolution 1200 ppi, which means 42,67 x 46,74 millimeters. Lenticular lines are horizontal. This is all set in Photoshop.

Setting in qimage:
Original size (so the same dimensions as before)
Media type: Photo paper pro platinum
Media size: A4
Orientation: Portrait
Printer profile: Let printer/driver manage color
Printer setup (Pro-200 driver): Photo print, Print quality custom-1 (highest accuracy), Photo paper pro platinum
Printer setup (qimage): Interpolation Forge (have tried others), Antialias off, Overdrive for both normal prints and poster, print sharpening off, spool all pages

I believe these are the max quality settings in each department. The same settings I originally used, when I DID get the 1200 ppi print (except I probably didn't mess with the Qimage printing options under Printer setup).
If the source image size changes, it doesn't affect anything when I print in original size which is defined in the file itself (TIFF format or exported to qimage from Photoshop).

Yes, the problem seems to be outside of Qimage. To my understanding there has been no update to the printer's own driver and since I already got 1200 ppi out from it, the driver can't be the problem. Now that I mentioned it, I can check if I can find an older version. It's a long shot though.

Also, if I was able to get 1200 ppi with the native driver, I never would have needed Qimage. I understand the point of the overdrive mode is to double the native max output resolution anyway.


Title: Re: Overdrive not working in Qimage One
Post by: admin on March 05, 2023, 07:16:46 PM
OK.  Those details help.  Before anything else, let me ask: you said you have Qimage set to Forge interpolation.  The interpolation setting is a Qimage Ultimate exclusive: you cannot select interpolation type in Qimage One.  So are you using Qimage One or Qimage Ultimate?  It matters because Qimage One doesn't have Driver AI.

Next, you seem pretty certain that you once got 1200 PPI and now you don't.  How do you know?  There is no way to determine the resolution of the printed output by just looking at the prints.  Is the assumption that you "got 1200 PPI" just based on how the prints look?  This is important because you are assuming you know when the driver is using/accepting 1200 PPI and you may not.  If one print simply looks less detailed than another, that could be anything: the driver could be accepting 1200 PPI in all cases and the cause for the loss of detail could be something else.  And I'll just reiterate one last time: that printer cannot produce 1200 PPI output.  There is no debate about that.  So at this point I'm going to ignore that fact and just concentrate on the fact that you say at one time it printed better than it does now.  So we'll go from there and ignore that you aren't going to get true 1200 PPI no matter what you do.

Now if you want some shots in the dark about what things to try...

First, you can hold the Shift key while you click "Properties" to open the driver settings.  That will cause Qimage to reload all the driver settings from Windows defaults instead of remembering what was done before.  Then set your settings (in the driver dialog) and give it a try.  If some odd setting worked its way into Qimage's remembered driver settings or there was an OS update that affected things, that could help.

Second, open the driver settings and click on the Page Setup tab.  Then click the "Print Options" button at the bottom and make sure "Prevention of Print Data Loss" is set to "Off" (see attached screenshot).  If that is on, I know the Canon driver will "chunk" the data to 300/600 PPI.  Now, Qimage Ultimate should do that for you (Driver AI) but it's still a good idea to check it anyway plus... you said in this thread you are using Qimage One which won't do this automatically so after you said something about "Forge", I'm not confused whether you are using Q1 or QU.

Mike


Title: Re: Overdrive not working in Qimage One
Post by: martyan on March 05, 2023, 10:51:56 PM
It's Qimage One and Forge interpolation is the first choice in the list (quality 10, speed 1).
Yeah, perhaps you're right and I didn't get 1200 ppi and it was something else. It's not possible to see 1200 ppi with the naked eye, but in the finished lenticular image it's possible to actually count the frames. I printed a picture with 30 lpi lens and to my recollection I was able to count 40 frames - this would only be possible if it's a 1200 ppi print. Unfortunately I don't have that particular picture anymore so I could check.

Why is it that pixma pro-200 cannot produce 1200 ppi output? It offers the same 4800 x 2400 max dpi as pixma pro-10, which does produce 1200 ppi. I had test prints from Canon for three models: pro-10, pro-200 and pro-300. Pro-10 was the only one with 1200 ppi (I'm sure of this), but I chose to buy pro-200 because the overall print quality was clearly sharpest of the three. And because I understood that with Qimage you can double that native 600 ppi.

If it's not because of the max dpi resolution, what is the hardware limitation?

And when does the Qimage overdrive actually produce twice the ppi that the native driver offers? Say the native driver supports 1200 ppi, why do you need the overdrive since you can just choose the max setting to get 1200?


Title: Re: Overdrive not working in Qimage One
Post by: admin on March 06, 2023, 12:36:25 PM
And when does the Qimage overdrive actually produce twice the ppi that the native driver offers?

Qimage always produces twice the PPI that the native driver offers whenever you have overdrive selected (up to 1440 PPI) but it is up to the driver as to what the driver will actually do with that extra data.  And that last part (how the driver handles 1200 PPI input) is obviously not a Qimage question or anything Qimage can influence.  On a Pro-10, Pro-100, and Pro-1000, the driver actually runs at 1200 PPI if you go to the Page Setup tab, click Print Options, and make sure "Prevention of Print Data Loss" is set to "off".  For some reason, it looks like Canon dumbed down the Pro-200 and Pro-300 drivers so they run at 600 PPI under the same conditions and there is no longer a 1200 PPI option.  My guess is that they determined that there is very little difference in visible output between 600 and 1200 and little benefit to offering 1200 PPI, and that 1200 PPI might have caused trouble in some applications that are less capable (than Qimage) due to memory problems.  Their own Print Stuio Pro may have even had a problem with it, who knows?

I've tested overdrive on printers that don't have 1200 PPI native (like the G620) and I've always seen some benefit so I doubt they are throwing 3/4 of the data away... but the results have to be scanned at 1200+ PPI and at that magnification you can see individual printer dots.  In addition, you only get a small improvement in high contrast detail like black and white lines because the printer can't produce full color at 1200 PPI.

Quote
Say the native driver supports 1200 ppi, why do you need the overdrive since you can just choose the max setting to get 1200?

You don't.  That's why if your driver runs at 1200 PPI, your top choice will be Max 1200 PPI and there is no overdrive option.  This is what happens in my above example with the Pro-10, Pro-100, and Pro-1000.

Mike


Title: Re: Overdrive not working in Qimage One
Post by: admin on March 06, 2023, 01:19:29 PM
Here is a test I just ran on the Canon G620 and scanned at 1200 PPI.  The G620 is not even a pro printer and it's max driver resolution is 600 PPI but it still shows a small detail difference when you use overdrive.  Notice how only the high contrast detail is improved like the black numbers in the clock and the black and white cloth on the left.  Other areas like the person's hand, golf balls, etc. look the same and at this level of magnification you can see why: there just aren't enough printer dots to resolve full color but contrasty light/black areas can benefit.  Overall you wouldn't really look at the one on the right and deem it as a better print unless you were looking at this extreme magnification and looking in very specific areas.  The whole print from left to right here is 13mm wide (half inch) so this is an extreme magnification of the print.

Original image was 3600 pixels wide, printed at 3 inches across so the original had 1200 PPI worth of data.

Mike


Title: Re: Overdrive not working in Qimage One
Post by: martyan on March 12, 2023, 05:15:45 PM
Right. I've done more experimenting and I have had success. As I told before, with the Qimage One demo version the overdrive seemed to sometimes work the way I wanted, sometimes not. Now I know when it doesn't.

If I produce 24 frames for my 50 lpi lens, it becomes a 1200 ppi image file. Whether I print it directly from photoshop using the Pro-200 driver or with Q One using the 1200 ppi overdrive, what comes on the paper is just 12 frames - no hint of the missing inbetween frames.

However, when I produce 18 frames (900 ppi) again without Qimage the frames that go beyond the 600 ppi max resolution are dropped. But with the overdrive ALL the 18 or frames turn up in the print! And seen through the lenticular sheet the difference is remarkable compared to a 600 ppi print.

It this is the way it works, I'm okay with that. 18 frames is a lot better than 12. Anyway, it would be interesting to know what happens when you work with a 1200 ppi image and the overdrive just drops every other line.

I'm sure with more than 600 ppi the individual lines are not totally sharp and some bleeding happens (that's why you usually do see 3 frames at once, though one of them pops out more), but still the full data is transported from photoshop to Qimage and also to the paper. Why then does it work with 1000 ppi and not with 1200 ppi?


Title: Re: Overdrive not working in Qimage One
Post by: admin on March 12, 2023, 09:30:34 PM
I'll say it again, what you are doing has absolutely nothing to do with Qimage or Overdrive so I want to be clear: Qimage and Overdrive are always working!  There is never an instance where "overdrive doesn't work".  Overdrive is working fine.

What you are running into is what I've been telling you from day one: no inkjet printer can actually produce 1200 PPI on paper.  So what you are running into is the fact that 900 PPI gives you just enough detail to be able to discern individual frames (lines in this case).  Going beyond that, the hardware simply cannot handle it.

Also, the demo didn't operate any differently than the registered version and... it didn't work sometimes and not others: it worked every time.  What is happening is that depending on what you print, how sharp it is, and how much it differs from frame to frame, some images (or areas of images) may look like they have some separation at 24 frames while others will not.  And we are back to the bottom line which is, you are asking your printer to print beyond its hardware capabilities.  Overdrive will help (as you found out) but it is not a substitute for hardware limitations.

It's sort of like going to a Chevy dealer and taking a Corvette for a test drive.  Later you express concern with the dealer after you buy it that it won't go 210 MPH like it did on your test drive.  Then the dealer finds out you measured your speed on the test drive on a 10 percent downhill grade with a 40 MPH tailwind.  The car is doing the same thing every time.  You just can't expect it to reliably perform beyond its specs 100% of the time.

Mike