Not scanning to pdf in black and white. PDF file size much bigger than expected

[SimonK147]

Using scanning software supplied with the printer.

Scanning two page colour doc to black and white pdf file.

Image produced appears as black and white when viewed in a pdf reader but file size is large compared to a scan on my brother portable scanner (932KB as opposed to 61KB).

Examination of header of produced pdf shows:

/XObject /Subtype /Image /Name /Im1 /Width 1654 /Height 2338 /Length 454440/ColorSpace /DeviceRGB /BitsPerComponent 8 /Filter [ /DCTDecode ] for each scanned page.

Header from my portable scanner for same doc and scan settings:

/Subtype/Image/Length 31668/Width 1662/Height 2344/BitsPerComponent 1/Filter/JBIG2Decode/ColorSpace/DeviceGray/Decode[ 1 0]>>stream

Why is this?

Bought this AllInOne" for the docment feeder on the scanner.

Scanning large, multipage docs for archiving.

Small filesize more important than high resolution/colour.

Large pdf filesize produced makes this product unsuitable for my application.

[banhien]

@SimonK147 

From the list, there is an option called Save as PDF. Please use that option ?

Regards.

[SimonK147]

Thank you for the response.

"Single sided doc" is my custom setup, based upon "save to PDF"

As you can see from the right-hand side of the screenshot, the save format is PDF.

The output file is definitely a PDF as it can be read by a PDF reader. The issue is why it is being output in 8 bit rbg instead of 1 bit b&w as selected and why the file size is so much bigger than the same resolution b&w PDF created on my portable scanner

[SimonK147]

Following up on my above question,

Repeated tests using default "Save to pdf" profile as suggested.

Note the confirmation of black & white 1 bit in the 2nd settings page below.

File size of result is 2.6MB.

Note the difference to a scan of the same document with the same settings on my Brother DSmobile portable. Less than 10% the size.

Header of the file output by the 5200 still shows RGB 8 bit.

%PDF-1.7

1 0 obj

<</Type /XObject /Subtype /Image /Name /Im1 /Width 1181 /Height 1652 /Length 311139

/ColorSpace /DeviceRGB/BitsPerComponent 8 /Filter [ /DCTDecode ] >> stream

I also scanned the same doc in full colour on the Brother. 1.5MB, still 1/3 smaller than the allegedly black and white scan on the 5200.

Anybody know what, if anything, I'm doing wrong or should I just return this device for credit?