I scanned and combined several png files into a single pdf file using Acrobat 9. One of the pages (in this case the last page) becomes extra big.
To solve the problem, I tried exporting all pages into individual png files again, and then recombined them using Acrobat 9 again. Still the problem persists.
Next, after exporting all pages into individual png files, I converted all into individual pdf files before combining the pdf files, again problem persists.
I analysed the file sizes and pixel numbers of each png file, they are all similar.
Fed up, I copied all png files into a Word document, then printed the Word document into a pdf file. This works but it is not ideal because the solution is laborious and also, the files don't look original any more. That's the reason why I extracted in png format to begin with, so as not to loose information.
Below is a screen shot showing two normal pages followed by the last super big page:
Hope someone can help me please
If the number of pixels is the same it means that the resolution (ppi) value of the last page is much lower for some reason.
What are the page sizes in inches or cm of the large and small pages, and size in pixels, and ppi if known?
Problem solved. In order to answer your question, I had to examine the numbers more closely. I normally use Microsoft Office Picture Manager which only shows me the pixel numbers and the pixel numbers are indeed quite similar, ranging from 3761 pixels by 5816 pixels to 3763 pixels by 5818 pixels.
Then I opened up the files using paint to check for more numbers. There, I found that only the last page is 240 dpi while the rest of the pages are 600 dpi. So through Google, I learnt to use photoshop to change the dpi of the last page from 240 to 600 without re-sampling the image and now all the pages look the same size.
I also remembered that I did some editing to the last page using paint. Somehow, that changed that page's dpi without my realisation.