Filesize vs. Pixels Question…

[Wogus]

I’m new to posting in the Farktography threads and I hope this isn’t stupid question, but here goes. Overall I consider myself fairly computer literate, but that being said I can’t figure out how some photos posted in the Farktography threads are as large as they are on-screen while having such tiny filesizes (as measured in KB).

Here’s a little example using actual numbers from two pictures in the “Birds and Birdwatching” thread.

One of my submissions, let’s call it PIC A, is 640 x 425 pxl’s with a filesize of 213KB. Another pic in that thread, let’s call it PIC B, is 640 x 960 pxl’s with a filesize of 140KB. PIC B displays larger on-screen by almost half (44%) but is one third smaller in filesize (KB).

So yeah, my quesion is this: How are you guyz compressing your pics? I’m shooting in RAW format but obviously converting to .jpg for submitting. I want to be able to post a larger, on-screen picture in the thread but the forum software keeps hammering me about the filesize being too big and such. Using the .jpg “compression slider” gave only tiny differences regardless of the degree of compression I chose so I’m guessing that’s not the answer…

Thanks in advance.

[sleeping]

Partly it depends on the content of the file itself – the more fine detail there is in an image, the less it can be compressed. Things like foliage and fine detail in feathers will make the file size larger no matter what.

Also, as well as the image data itself, JPEGs can contain quite a lot of other metadata (camera settings etc). If you use a method that discards that data (e.g. “save for web” in photoshop) it can make the file smaller too.

If you don’t have PS, there’s a very decent alternative “save for web” program called RIOT: http://luci.criosweb.ro/riot/ It’s available as a plugin for some other image editors (GIMP, irfanview) too

[Wogus]

Awesome sauce!

I do use IRFanview quite a bit so I’m looking into the RIOT plug-in ight now. Some of the other stuff, like Meta-data, had not even crossed my mind.

Thanks mucho!

[chupathingie]

Ahhh, Irfanview… how I miss you. One of the few apps I have not found a suitable substitute for in Linux…

[ravnostic]

Irfanview has been giving me troubles since the last two updates. :o( Won’t ‘save for web’ the normal way, though there’s the work-around for it that results in images of nearly as small a size.

[Wogus]

Ahhh, Irfanview… how I miss you. One of the few apps I have not found a suitable substitute for in Linux…

Ah Linux… How I (sometimes) miss YOU…

The RIOT plugin appears to working like a charm, btw… Pretty much exactly what I needed.

[Yoyo]

I love me some Irfanview. Easy install, efficient use of resources, opens Canon CR2 raw files. (And now that I’ve got the PDF plug-in thingy, it’s even more awesome. My forgery, er, um, I mean, image editing has gone to a whole ‘nother level.) I haven’t got the RIOT plug-in, but typically 90% quality on jpgs gets things down to the size needed for Fark. I might need to look into installing it.

As for any exif data, I’m using “exiftool”. Only to read exif data presently, but it will edit as well.
http://www.sno.phy.queensu.ca/~phil/exiftool/

[Author]

Posts