advise on uploading pictures and thumbnails

[brucegseidner]

What are optimal ways to share photographs and graphics on this forum. I can be pretty concrete so please keep it simple.

I especially like the thumbnails that can be enlarged by clicking on them and appear embedded with the text rather than links to external url's.

Thanking all in advance.

[planet10]

There are 2 methods. Put the picture into cyberspace & link to it. Around here most internet service comes with some webspace that you can use.

Note that if you do it this way, and you change ISPs or delete the pictures the links will break and future thread readers will miss the pleasure of your pictures.

Personally i dislike the thumbnails that take you to an extrernal photosharing site. They tend to be too intrusive & too fiddly. from a viewer POV.

The other way is to embed the picture in the thread. You are limited to 1/post and 100kB, 1000x1000 pixels. You can be assured thou that it will be with the thread forever.

Scheamatics & diagrams should not be in jpg format. Limited colour gif is my preference, althou png works as well.

dave

[Mr Evil]

Originally posted by planet10
...Scheamatics & diagrams should not be in jpg format. Limited colour gif is my preference, althou png works as well.

PNG is better. It yields smaller files in almost every case, plus it supports >256 colours and an alpha channel if needed.

A few things to note about PNG:

• A lot of software capable of saving as PNG does a really bad job of the compression, notably Photoshop. If you use such software, you can recompress the files with something like PNGGauntlet, which will decrease the file size a lot.
• PNG supports 24 bit colour, but this is only rarely needed, so it's best to convert down to 8 bit (256 colours) or 4 bit (16 colours) before saving, for a much smaller file. Don't use dithering.

[planet10]

Originally posted by Mr Evil
PNG is better. It yields smaller files in almost every case, plus it supports >256 colours and an alpha channel if needed.

>256 colours is of no consequence when one is taking about files that would prefer to be 8 colours or less (ie the kind of files i'm talking about)

gif has an alpha channel.

PNGGauntlet

Next to useless for those of us with Macs. AFAIC, if i can't do it in PhotoShop or Graphic Converter then there isn't much point.

dave

[Mr Evil]

Originally posted by planet10
>256 colours is of no consequence when one is taking about files that would prefer to be 8 colours or less (ie the kind of files i'm talking about)

Maybe so, but the capability is there if you need it. It's not hard to exceed 256 colours in e.g. graphs with antialiasing.

Originally posted by planet10
gif has an alpha channel.

GIF has only 1 bit transparency, not an alpha channel (8 bits in the case of PNG). Not useful for posting schematics here though.

Originally posted by planet10
Next to useless for those of us with Macs. AFAIC, if i can't do it in PhotoShop or Graphic Converter then there isn't much point.

It's annoying that more software isn't cross-platform, but PNGOUT, on which PNGGauntlet is based, does have a Mac port. It's only really needed if the software you're using doesn't do the compression properly (I don't know if new versions of Photoshop are still bad there).