Another Size Topic

[56_kruiser]

I took some shots for someone who indicated they wanted the file size smaller.

I took the shots at the L size in my Canon 80jD. As an example, a shot is 5999X3999 and is 300 dpi.

They are going to put in a web page, and so I thought that if I changed the dpi to 72, and exported, that the file size would be smaller, while maintaining 5999X3999. Turns out after the export it was larger. Original is 9.86MB and the exported one at 72dpi is 14.7MB.

I guess I need to select lower quality in the export, no? What would be the suggested safe type/size, etc., for used in brochures, web site, etc.?

[EDIT]

I would also like to know what size is recommended to deliver to a realtor for MLS listings.

 

 

[kaffeeundsalz]

Well, 5999x3999 pixels are 5999x3999 pixels. You are not reducing the size of the image at all, so why should the filesize be significantly smaller? As for DPI, it doesn't matter if you squeeze 72 or 300 of your pixels into one inch. They're still the exact same amount of pixels. DPI is just a logical value that is stored with the image and that's only important for printing, i.e. when you have to translate the pixel dimensions into actual units of length.

As for your exported image being larger than the original, that's probably because you've used less compression when saving the image. But again, this step is useless since you didn't change anything in your actual image.

[R C-R]

16 hours ago, 56_kruiser said:

They are going to put in a web page, and so I thought that if I changed the dpi to 72, and exported, that the file size would be smaller, while maintaining 5999X3999.

Watching the Understanding DPI video tutorial and/or reading the Understanding DPI Affinity Spotlight article may help you better understand why this does not do what you want.

[John Rostron]

22 hours ago, 56_kruiser said:

indicated they wanted the file size smaller

You need to ask them: do they mean smaller in pixel dimensions (600 by 400 say) or smaller in bytes on the disk? These have quite different solutions.

John

[Alfred]

1 hour ago, John Rostron said:

You need to ask them: do they mean smaller in pixel dimensions (600 by 400 say) or smaller in bytes on the disk?

If they said “file size”, not “image size”, they should mean bytes on the disk.

[John Rostron]

1 hour ago, Alfred said:

If they said “file size”, not “image size”, they should mean bytes on the disk.

I know that, and you know that, but do they know that.

John

[56_kruiser]

Yes, they meant file size. 

Agreed, I need to read the stuff linked above re: DPI.

So, it seems to me if I want a smaller files size I need to do 1 of 2 things: Save with less quality, or make the pixel dimensions smaller.

Would you agree?

[John Rostron]

2 minutes ago, 56_kruiser said:

Would you agree?

Yes. It might be worth checking the smallest acceptable image size, then reducing the quality to suit.

John

[gdenby]

Ask the realtor what they want. Depends on what their printer wants.

I just looked at the manual for the Canon 80D. There are 2 L size .jpg. The larger is supposed to be a bit over 7 MB in size. So I wonder how it turned out close to 10.  It is also of a size, A2,  that is big enough for paper printing a wall poster. The S1 size might be more appropriate for either full web screens or a brochure. It is close to a US letter size page. 

My guess is that the image should be reduced to something like 1500 x 1000. At that size, it would likely fill up most browser windows. It should be enough to print as a horizontal panel in a single folded brochure. 

Note: if exporting from Affinity, it appears that .jpg is always set to 100% quality. 90% quality is close to as good visually, and can have a file size 30% smaller.