HyperPhysics Image Issues: Difficulties Helping Physics Questions

[dlgoff]

Not being able to insert images from HyperPhysics makes it difficult to help answer physics related questions. For me anyway.

 

[berkeman]

Have you tried right-clicking and selecting Copy Image Address? That's how I captured this image

URL -- http://hyperphysics.phy-astr.gsu.edu/hbase/magnetic/biosav.html#c1

Image -- http://hyperphysics.phy-astr.gsu.edu/hbase/magnetic/imgmag/bsav.gif

EDIT -- Hmm, that's weird. It shows up in the Post Preview, but is an X in the post...

 

[dlgoff]

Yep. That's what's happening for me.

 

[berkeman]

We need Superman's help! @Greg Bernhardt

 

[berkeman]

How about if I save the image to my PC first, and then UPLOAD it...

http://hyperphysics.phy-astr.gsu.edu/hbase/magnetic/biosav.html#c1

Okay, that's one way I guess...

EDIT -- added attribution URL per mfb's comment below.

 

[dlgoff]

When I tried that one this scalar product image to paint I get:

edit: but could be my paint settings?

 

[mfb]

That is a transparency issue.

Concerning the direct inclusion: apparently hyperphysics does not allow that. For a good reason, I guess: please be careful with copyright.

 

[jtbell]

Let me try it... saving it... uploading it...

(from http://hyperphysics.phy-astr.gsu.edu/hbase/vsca.html)

Ta-da! Just save it directly to your desktop or some other convenient location, and upload it. Don't touch it with Paint or any other program. It has a transparent background so it picks up the background color of the page it's pasted into (light gray here, beige on Hyperphysics). When I open it in Photoshop, I get a gray/white checkerboard background indicating that it's really transparent. When I convert it from "indexed" to "RGB color" and "flatten" it, I get a white background because that's how I've set the default background color in Photoshop.

I think mfb has the right idea here. Hyperphysics probably has set up hotlink protection for images. I do the same on my own site, with exceptions for certain specific sites like PF. I think when you insert the image URL and preview the post, your browser simply takes the image from its cache because you've viewed the image before. Then when you post, the forum software tries to fetch the image from Hyperphysics and fails because of the hotlink protection.

 

[jtbell]

When a website implements hotlink protection, it's probably either to save bandwidth (i.e. reduce the load on the server) or to protect copyright, or both. For my site, the motivation is mainly bandwidth. If someone hotlinks an image on a popular forum, it can generate hundreds of hits per day. There are forums where people think nothing of hotlinking 5-10 images from the same site in a single post. At ~250 KB per image, that adds up pretty fast.

But if you make a copy of the image and upload it to the forum, that's a copyright violation unless the owner allows it. Maybe Greg can contact whoever maintains Hyperphysics and ask for permission for PF users to post copies of their images when accompanied by links to the original pages like berkeman and I added.

I put my name and date on all my images, and let people post copies for non-commercial purposes, so long as they leave the name intact. That way I get free publicity.

 

[berkeman]

If we just post one or two images and include the URLs, is that protected under the Fair Use Act?

 

[Nugatory]

If we just post one or two images and include the URLs, is that protected under the Fair Use Act?

Almost certainly not. If you use content in such a way as to provide the same information as the copied site (making a visit to that site unnecessary) it's very difficult to claim fair use. If you want to reference content from hyperphysics... Link to it.

 

[berkeman]

If you want to reference content from hyperphysics... Link to it.

Thanks!

 

[Greg Bernhardt]

Here is the error

http://hyperphysics.phy-astr.gsu.edu/hbase/magnetic/imgmag/bsav.gif could not be fetched or is not a valid image. The specific error message was: Read timed out after 3 seconds

 

[dlgoff]

Maybe Greg can contact whoever maintains Hyperphysics and ask for permission for PF users to post copies of their images when accompanied by links to the original pages like berkeman and I added.

I always accompany posted images with the original page link and would have here. Hopefully Greg can get their permission as I appreciate the rules of copyright.

 

[dlgoff]

Read timed out after 3 seconds

So what to do?

 

[Greg Bernhardt]

So what to do?

Still working on it :)

 

[Greg Bernhardt]

It's possible they blacklisted our IP for excessive hotlinking

 

[dlgoff]

It's possible they blacklisted our IP for excessive hotlinking

 

[Greg Bernhardt]

I'll see if I can contact them

 

[jtbell]

It could be that their server is simply getting bogged down in general. Lately it seems to me that when I click on a link to Hyperphysics in a Google search, it often takes a long time to respond.

The specific error message was: Read timed out after 3 seconds

That suggests a slow server. Hotlink protection via rules in the .htaccess file (or something similar on a non-Apache server) would quickly return a 403 (Forbidden) status code.

 

[JorisL]

It could be that their server is simply getting bogged down in general. Lately it seems to me that when I click on a link to Hyperphysics in a Google search, it often takes a long time to respond.

I've even seen periods when I couldn't connect at all so this could be a viable explanation.

 

[Astronuc]

Here is the error

http://hyperphysics.phy-astr.gsu.edu/hbase/magnetic/imgmag/bsav.gif could not be fetched or is not a valid image. The specific error message was: Read timed out after 3 seconds

I was able to view the image this morning without any delay.

 

[dlgoff]

It's possible they blacklisted our IP for excessive hotlinking

Hotlinking and Bandwidth Theft

I didn't even consider that my inserting image urls (hotlinking) was actually theft. Sorry HyperPhysics and @Greg Bernhardt.

 

[jim hardy]

Thanks Don
i had no idea either
okay, from now on i'll only use that image icon above for images already uploaded to PF .

 

[jim hardy]

okay, from now on i'll only use that image icon above for images already uploaded to PF .

And for ones at hosting sites like Photobucket who exist for that purpose.