Help! Botched another airplane!

[cfuruti]

Originally Posted by murphyaa

That might be your issue. Does it only happen with the pages you've modified?

I've noticed that if I import a part done at 300 pix into a 200 pix sheet, it's significantly larger than the same part at 200 pix.

300 pix or dpi ? dpi makes more sense, because it means its pixels are meant to be rendered 300 / 200 - 1 = 50% more densely than if at 200 dpi - therefore, if you mix different resolution rasters, the 300 dpi ones should be rescaled* to 200 / 300 = 66.67% in order to appear at the same size.

* whether rescaling changes the byte count in the PDF depends on your software - it could either actually downsample the raster, reducing size and quality, or keep all the pixels and tag the image to render more densely.

[PaperMangler]

I had a major problem until I realized that when printing with "Borderless" selected the printed image was stretched slightly more in one direction than the other. Trashed three attempts on a complex model until I discovered this setting.

[murphyaa]

The setting is called "Pixels per inch". I just shorten it to pix, because whenever I think of dpi or dots per inch, I think of inkjet printer resolution, which is a different thing, as far as I understand (which isn't very far).

[cfuruti]

Originally Posted by murphyaa

The setting is called "Pixels per inch". I just shorten it to pix, because whenever I think of dpi or dots per inch, I think of inkjet printer resolution, which is a different thing, as far as I understand (which isn't very far).

You'd better say "ppi", since "pix" suggests a dimension, while dpi and ppi are kinda densities. But you're correct in making a difference between dpi and ppi.

Tedious-semitechnical-explanation-to-be-skipped-at-will 1: pixel counts are virtual dimensions: a raster image 100 pixels wide and 100 pixels tall has 100 x 100 = 10000 pixels; a second image with 200 x 200 pixels has four times more pixels and will demand four times the disk space (not counting compression). A "per-inch" density is a setting completely independent of pixel count, but coupled they both specify physical dimension: if the second image is set to 100 ppi, it will be 200 pix / 100 dpi = 2 inches wide; printing the first one at 50 ppi would render it at 100 pix / 50 dpi = exactly the same size on paper, but of course with a coarser quality.

T-s-e-t-b-s 2: "process" printers like you and I have at home use only 3 or 4 ink colors; there are no e.g. dark or pale yellow inks, only plain old yellow; therefore they simulate lighter or richer tones of, say, yellow by using different densities of actual yellow spots ("dots") [this approach goes astray in nonwhite paper, of course]. Therefore, each virtual "pixel" in your image will be rendered by a roughly square matrix of physical dots (the square size is calculated as above), and dpi resolution is larger than ppi resolution* by a factor n. If n is large, more combinations of inked/non-inked dots per matrix are possible, therefore more variations of light/dark yellow are possible; on the other hand, physical pixels get larger and less detail is possible. And vice versa with smaller n, nothing is perfect.

* since dpi and ppi are different, which of them are printer manufacturers more likely to advertise? One guess only.

T-s-e-t-b-s 3: Screen resolutions are of course ppi, since unlike process printers, screens can vary light intensity

[elliott]

Ow! Head hurt!

So, to get back to the original question: How does this affect poor Les? What does he need to do?

[umtutsut]

Originally Posted by elliott

Ow! Head hurt!

So, to get back to the original question: How does this affect poor Les? What does he need to do?

I've reprinted everything, triple-checking all the settings. We'll see how this try goes.

Les (The Voice of Authority)

[rjccjr]

Hi Umtutsut;

One of the great challenges of designing in card is drawing curved surfaces. Aircraft fuselages usually become a series of joined rings of varying diameters. Trying to join these rings can be very frustrating. One technique that you can use is to use small tabs rather than large backing rings. Eight small tabs on a circular segment will allow two sections to join with a pretty tight fit. If the design is fairly good in the first place parts will fit together very well, if it's not so good you might have to resort to cutting a lateral wedge along the bottom seam. Then join the incision from the back. That trick doe have its limits though.

Another trick is to save your model in a file on your computer, so that when you mess up, you can simply print out another page and try again.
Both of these can save a lot of frustration, if you tend to build a lot of models.

Hope this helps, rjccjr

[SCEtoAUX]

Something you can do if the pages in the pdf are different sizes is to choose a paper size for your printer.

In the print preview choose Fit.

In the preview panel side of the print dialogue (in Adobe it is on the right hand side of the print preview) there is a window showing the page as printed with the allowable printer margins of your page highlighted.

Above that window is a line that shows the percent the page is changed in order to fit on the page.

Below that window is a slider where you can step through each page.

Step through the pages and note the smallest percent for each page.

Use that percent to choose Custom Scale.

All of the pages should then be printed with the parts changed to the same percent.

I have used that procedure a few times and it has worked out so far.

You can test it out by using your goto graphics program and drawing a 10 cm line on multiple pages of different sizes but with the same resolution. Save the pages in a multi-page pdf and find out which is the lowest percent number then print the pdf at that percent. All of the lines should be the same length but at what ever percent was used. Example would be if the smallest percent was 59% then each line would print at 5.9 cm.

[murphyaa]

I'm still working on his statement that some model pages he prints straight from the file, and some he tweaks, then prints.

Les, have tried building one printed straight out of the box without any tweaks?

[MichaelS]

I have a he!! Of a time sizing Zio P kits. Something about the type of PDF he does.