original jpeg file size was 1.8MB, adding 3 words of text increased file size to 6.7MB - how do I keep file small?

[JDMF]

I've pretty much asked the full question in the title. I'd just like to add that I'd like to reduce the MB size of the text exclusively and not touch the original jpeg image at all. 

How do I keep the size of the new jpeg with the text included down near the original jpeg size without affecting the resolution of the original image? 

(I'm a complete novice here, so some terms you use might be new to me). 

Much appreciated. 

[Hangman]

Hi @JDMF and welcome to the forums...

Could you provide a few additional details to help us help you with this... or better still are you able to upload the JPEG file to this thread so we can take a look and find a solution for you?

Initial Questions

1. What are the pixel dimensions and dpi of you JPEG file?
2. What font size is the text you are adding to the file?
3. How will the final JPEG with added text be used, is it for print, for the web or for something else?
4. Should the JPEG with text file be RGB or CMYK?

[JDMF]

 

I've included the original jpeg 1.6MB, the new jpeg 6.3MB, and the affinity file that I used to create the new jpeg 6.9MBcover from comic 2004 v2.afphoto 

the new text is just my name at the bottom of the image.

does that help? 

cover from comic 2004 v2.afphoto

Edited March 2, 2023 by JDMF

[Hangman]

Hi John,

The main reason for the increase in file size isn't the addition of your name but the conversion of the file from RGB (the original JPEG) to CMYK in your final version where you've added your name. This will naturally increase the size of the file.

Adding your name and exporting the RGB version using JPEG (High Quality) from Affinity Photo generates a JPEG file of 1.3Mb. High Quality exports using a Quality setting of 85. Experimenting with the Quality slider a Quality setting of 70 will produce a JPEG file of 979Kb but it also starts to introduce artifacts, so ultimately it's a trade off between file size and quality.

I'm assuming the intended use for the finished file is for print, is that correct? Does the larger file size actually cause any issues or were you more just curious to understand why the file size had increased?

What file size would be optimal for your intended purpose?

It is possible to further reduce the file size by exporting the file to JPEG XL which supports layers and can store additional channels like selection masks and spot colors. It also supports CMYK for printing, though it would be important to check with any printing company whether they would accept a JPEG XL file. When exporting to JPEG XL, in High Quality mode the file size saving is around 70%, in Best Quality Mode around 57%. There are also utilities such as ImageOptim than can reduce file sizes further but it all depends on what the final use for the file is...

[JDMF]

it was a bit of both - "why on Earth did that happen?" and being told that smaller was better since the jpeg is being included as the cover for a script to download on Amazon, and apparently they keep more money based on file size (though I'm not sure what real difference 5 extra MB would make).

From layman's perspective, it struck me as odd that simply adding my name would make such a difference given that the original image is far more complex. 

I'd like to keep the original image untouched / unaltered, find a way to add my name while keeping the file around the same size as the original jpeg.

So, if I understand correctly, because the script just going to be used digitally, RGB is better. Is there a button I need to tick or some such when exporting to jpeg that does this or is my only option altering CMYK and using the quality slider / preset dropdown in the export section? 

by the way, thank you so much for answering me. Without knowing what sorts of key words and phrases to look up so that I could train myself, getting this far would have taken much more time. 

JMF

(quick update while I keep searching online, apparently an extra 5MB in size is a rather substantial cut of what Amazon gives you, so I definitely need to keep the file as small as possible without altering the quality of the original jpeg)

 

Edited March 2, 2023 by JDMF

[Hangman]

If you start with your layered Affinity Photo file where you've added your name and then go to Document > Convert Format / ICC Profile and select RGB/8 from the Colour Format dropdown and then sRGB IEC61966-2.1 as the profile, that will convert your CMYK file to RGB and keep it pretty much looking the same visually.

Exporting to JPEG now results in the following file sizes

JPEG (Best Quality) - 4.2 MB
JPEG (High Quality) - 1.2 MB

I've attached both exported files in the attached .ZIP file. Note: I've zipped them to prevent the forum applying any compression to the files but you can off course make the document changes above and export the file yourself...

Experiment with different Quality Slider values and then reopen the exported JPEG in Affinity Photo and zoom in to the image, espcially areas around the text to make sure you have a Quality Setting / File Size combination that gives acceptable quality with a workable file size...

That's no problem at all, I hope the info above is helpful and provides a workable solution for you...

cover from comic 2004.zip

[JDMF]

you are a hero. I'll let you know how it all goes. 

 

JMF