Noobee question on posting images here... - Page 1
Forum section: electronics / general

author: peteb2
author_rank: Regular Contributor
timestamp: April 16, 2016, 01:59:44 pm
content: Ok, so I have finally jumped in and begun making a few posts. Most importantly I have searched here as best I can on the acceptable process of posting up an image. I participate on a few other Forums about other passtimes and in which almost always, the picture embedded thing is a big issue. The no-no is image size too big so it obliterates a posting in all its glory. Most use the ... embedded function but I notice most Forums now auto set the size the image displays at as (a thumbnail) and clicking it provides it as original size.So as it has almost gone 2am here so can anyone please tell me if there are specific rules on image embedding please...

author: continuo
author_rank: Frequent Contributor
timestamp: April 16, 2016, 02:46:19 pm
content: I don't know if this is the correct way but as a rule of thumb I would:1.) If it's something not really important, let's say a funny pic or the likes, I would upload it onto some webspace and use the img tags to link to it (to save Dave traffic on his server).2.) If it's something important to the topic, let's say a schematic, worth keeping, I would attach it to the posting.

author: Ian.M
author_rank: Super Contributor
timestamp: April 16, 2016, 03:20:49 pm
content: There's also the issue of image quality. If the original photo was poorly lit or blurred, its purely a waste of everyone's time and bandwidth. To be useful for most purposes, board or component photos need to be high enough resolution to read the component markings. Crop anything that isn't needed, and use a plain background. A sheet of white paper is a good default choice for parts and smaller boards.Never use JPEG format for schematics or other line art. It inherently blurs fine detail e.g. small text or where lines cross, so to maintain quality you need a vast file size. GIF or PNG is a far better choice. Reduce the colour depth as far as you can without loosing detail. e.g for most computer generated schematics, 256 colours (8 bit) or even 16 colours (4 bit) palletized is fine. Scanned schematics are a lot more problematic, due to stains and dirt particles on the paper and uneven printing. If you want to get the filesize down while maintaining readability, you'll probably need to do a considerable amount of preprocessing at high resolution, full colour depth to tweak the gamma, clip highlights and lowlights and sharpen edges before you can safely reduce the colour depth and resolution. If the original was black & white, convert the scan to monochrome as soon as you've cleaned up any staining.Photos of schematics rarely work well unless you can keep the original flat, hold the camera rigidly directly over the center of the schematic and provide multiple off-axis light sources. Camera built-in flashes are generally more trouble than they are worth and should be disabled as they tend to cause a large illumination gradient across closeups. If you have nothing better, put the schematic on a flat surface in direct outdoor sunlight with the sun fairly high in the sky, and photo it standing over it.

author: Brumby
author_rank: Unknown
timestamp: April 17, 2016, 12:16:57 am
content: Quote from: Ian.M on April 16, 2016, 03:20:49 pm... avoiding casting shadows on it.

author: tautech
author_rank: Super Contributor
timestamp: April 17, 2016, 12:46:47 am
content: Quote from: peteb2 on April 16, 2016, 01:59:44 pmThe only rules are the file sizes and types, those are outlined the the "Attachments" when you are building your post.I've always tried to keep pics ~100Kb in order to save space on Dave's server but more importantly IMO to help pages with images to load faster for any viewers that might be on slow internet connections.However there are times when good detail is required and file size then need be increased to preserve image quality. Some member also provide links to image hosting services so the forum size limits won't apply and Dave's server space is further preserved.Thumbnails that appear at the foot of your posts can be embedded in the body of a post by copying the thumbnail address and inserting that address within your post and using the imgpic address/img syntax.