DHC-1 Chipmunk WAK model enlarged to 1:16

[gomidefilho]

Dear Leif

I watch with interest you thread, I buy many magazines but not encourage-me for build in full scale (1/33), is the oportunity to learn more...

best regards...

[Leif Ohlsson]

I am glad to see so many friends checking in already! Hopefully we will have a good time together.

Mike ("Bomarc") - as to your question about the Allison engine Mustang: Yes, I'm afraid it finally became too much for me to handle. I just had to prove that I still could do something basic, like actually building a paper model. Hence this thread.

However, a little bird has recently been whispering in my ear that another Mustang afficionado just may be trying out another way of dealing with the problem of the misplaced floor in the cockpit. I'm much looking forward to watch that!

Now for a couple of installments about things you have to do in the computer when you wish to enlarge a printed kit, before actually cutting or glueing anything.

Leif

[Leif Ohlsson]

The more I understand about what's going on in between scanner, graphic program, printer, colour profiles, etc. (and that isn't so very much, believe you me), the harder everything seems to become. Probably because I've become aware of a number of things I have learned that I ought not to accept in the finished result. But I have not yet learnt how to arrive at what I want to achieve in a systematic and repeatable manner. Preparing the print sheets of the Chipmunk is a case in point.

The scan resolution was set at 1238 dpi for the part sheets. If I change that later on (in a graphic programme like Photoshop or similar) to 600 dpi, the result will be exactly 1/16 scale. You arrive at the figure 1238 by the following formula: 600 (intended dpi of print sheets) x 33 (original scale) / 16 (intended scale).

What with a number of upgrades of computer and software, my scanner nowadays keep turning out scans that are just way too light, at least juding from what I see on the screen. (What the scans would look like in print is another matter, which I discovered later…) Wanting to make all scans alike, I found a setting for the scanner's level control that would render both acceptable previews and finished scans, judging from the output of .tiff-files.

In my case the settings were (and this is included just as an example of what kind of data you would want to make a note of in your own case, in order to get the same result for all scans):

Resolution: 1237.5 (or 1238), which will render 1/16 scale if changed to 600 dpi
Levels or light intensity: 20
Saturation: 50
Unsharpen mask: High (this is to avoid so called moirée, or dotted patterns in the scan)
Descreening: Fine print (175 lpi). I am uncertain what this is about; fine seemed appropriate

Here is a contact sheet of the parts scanned:



As you can see there are four full pages of parts that need to be rearranged into much smaller sheets eventually. In addition there is about half a page of roll-up parts and wire templates. I also scanned the instructions (bottom row) - they are convenient to have handy as a separate printout. The instructions were scanned at 300 dpi, as no change of size will be made of them. They are just for reference.

One final thing was done to the raw output from the scanner - all five .tiff-files were corrected ever so slightly for a known aberration in my scanner. A thread on the site by YankeeBoy alerted me to investigating the extent of my scanner distortion. I found that the output needed to be enlarged 0,3 percent along the short side. So I enlarged all five .tiff-files along the short axis (horizontal so far, see contact sheet above) to 100.3 percent in Photoshop.

This is another thing you may want to find out about. It is very likely that your scanner, too, produces some noticeable distortion, which will result in a possible bad fit of parts later on.

Any thoughts on scanner distortion, or scanner settings?

Leif

[malachite]

Hi Leif,
I have always read your postings with great interest and it looks like this one will cover all the bases, so I will be following this tread with interest but not necessarily contributing as my skills are not that good.

[cardist]

Hi Leif,
Glad to see that you are providing us with more top quality work. I look forward to watching and learning.
Happy modelling,
B.

[Gil]

Hi Leif,

You've brought up the subject of nightmare dreams - color management with scanning followed by vain attempts at printing reasonable facsimiles. I've delved into this several times and came up with barely passable solutions [though if you squint some it's OK].

The following site is one of the best I've found for those wishing to further delve into this arcane art: Scanning Basics 101 - All about digital images

Hope this helps, +Gil

[OhioMike]

Does any co. already produce in 1/16 scale, specifically WWI subjects? I hate to think the only option is learning the intricasies of japanese electronics for larger scales as being the only option?

[wag]

e-cardmodels has a Nieuport 11 in 1/16
1/16 Nieuport 11 Joseph Vuillemin - ECardmodels.com Shop - Downloadable models and crafts for
other that that I don't know of any currently available.
Wayne

[Leif Ohlsson]

Gil, thank you for the link to "Scanning basics 101"! Even if it surely contains more than 101, I'm sure many will save it and use it as a standard reference in the future. Whenever one is in doubt about anything to do with scanners, it would be something to check first.

Reading (or skipping) through the relevant pages for me, I discovered several things I have been doing wrong, or without any added benefit:

Printing resolution: It seems that modern inkjet printers really don't produce any better results at print resolutions above 240-300 dpi. This means that my intended resolution of 600 dpi (and therefore scanning at 1238 dpi) is way to high. I will aim at a print resolution of 300 dpi in the future. Very good to know.

Scanning resolution: Scanning at 600 dpi is good to avoid moirée pattern (the interference pattern of dots appearing as a result of a pattern of dots already present in the printed image we scan, and the pattern imposed by the scanning software). I will therefore scan at 619 in the future and change it to an even 300 in order to rescale from 1/33 to 1/16.

Matching scanner, monitor, and printer: This is - like you said, Gil - evidently very difficult but crucial. A few installments ahead there will be reason to come back to this issue. The link is to the relevant section in "Scanning Basics 101".

I hope I will be able to work out some combination of settings for the future. As I see it now, the way to go for me would be to keep the monitor setting I have (can't stand looking at a screen which depicts colours way off just in order to get printing right).

Then I will use some test image consisting of standard colours, plus the ones most common in the model I'm working on, and work out a print setting. This will require many test prints, and the test sheet therefore should be small. The adjustments should be made in the printer settings, not the graphic programme settings.

Once a successful printout has been achieved - where the printed sheet will look like the image on the screen - I will scan that, and adjust the scanning contols to produce something looking right on the screen, and then test print it. Further adjustments will then be made to the scanner settings.

Have I got this right? Quite an arduous task, I must say. We shall see whether I'm up to it in the future. I certainly hope so, since I'm very tired of things not turning out the way I intend...

Leif

[Tapcho]

Remember that image size and image resolution are two different ratios. Don't mix them and don't use one to control the other. If you long for a strong workflow in scanning try this: Amazon.com: Real World Scanning and Halftones (3rd Edition) (0785342241327): David Blatner, Glenn Fleishman, Steve Roth, Conrad Chavez: Books

BR Tappi