Mathematical equations in OPF posts

[Ted Cousins]

I put the source image here for grins - site is powered by Misago, not Xenforo ...

Posting Real Equations here

Started by xpatUSA on July 27, 2026 in the Technical Discussions category. 29 replies, last one from Aug. 3, 2026.

dprevived.com

 

[Doug Kerr]

I now think that our aspiration as to the display size of equations included in OPF posts as pictures should be:

The display size of an equation, with respect to the display size of the body text of the post, should be consistent for all observers (and thus consistent with that established and seen by the originator).

I have no idea to what extent this is attained by the modus operandi that has been discussed here.

But here is a simple check, repeated here from an earlier post:

What will follow is, first, a phrase just as regular body text in this post, followed with a "picture" of the same text (as is it were an equation) with its display size in the post set to make it, as I see it here, essentially match in size the text just above it.

The quick brown fox

It would be good to hear if those two phrases had essentially the same size as seen at various other stations.

Best regards,

Doug

 

[Ted Cousins]

I now think that our aspiration as to the display size of equations included in OPF posts as pictures should be:

The display size of an equation, with respect to the display size of the body text of the post, should be consistent for all observers (and thus consistent with that established and seen by the originator).

I have no idea to what extent this is attained by the modus operandi that has been discussed here.

But here is a simple check, repeated here from an earlier post:

What will follow is, first, a phrase just as regular body text in this post, followed with a "picture" of the same text (as is it were an equation) with its display size in the post set to make it, as I see it here, essentially match in size the text just above it.

The quick brown fox

It would be good to hear if those two phrases had essentially the same size as seen at various other stations.

Best regards,

Doug

Sadly Doug, here it is as seen by me on Misago (nova DPR):

Sreenshot:

 

[Doug Kerr]

Hi, Ted,

Sadly Doug, here it is as seen by me on Misago (nova DPR):

Well, that doesn't even come close (never mind the color problems)!

Is this as seen with you "logged into" to the OPF site the way you would ordinarily do that?

I am confused by the reference to Misago etc. I had thought that Misago was a forum software (perhaps the forum software of the "Nova DPR" site).

I'm not sure how that would get into the picture if you logged onto the OPF site.

For example, I log into the OPF site using my browser, Firefox. No forum software gets into the picture other than that used by the OPF site.

Obviously there is an important part of this story I don't know.

Thanks.

Best regards,

Doug

 

[Ted Cousins]

Hi, Ted,

Well, that doesn't even come close (never mind the color problems)!

Is this as seen with you "logged into" to the OPF site the way you would ordinarily do that? (I am confused by the reference to Misago etc.)

No. I was logged in to DPRrevived which is "powered by" Misago ( https://www.google.com/url?sa=t&sou...AQFnoECBgQAQ&usg=AOvVaw36FO2pAUucGn9CzAh3NdIs), not XenForo.

For example, I log into the OPF site using my browser, Firefox.

Thanks.

Best regards,

Doug

While in "the other site", I accessed your post here via your post-here's URL and made a screen shot.

I guess that you could do the same via here:

Posting Real Equations here

Started by xpatUSA on July 27, 2026 in the Technical Discussions category. 30 replies, last one from Aug. 4, 2026.

dprevived.com

"unfurl" ... hmmm ...

Accessing your 320x37px .png direct in OPF also displays a larger image. I think there's a clue there ...

Good luck,

Ted.

 

[Ted Cousins]

My current issue with the "grail" is having to jump through different hoops in the various sites that I visit, not just OPF.

And, in DPRevived (Misago) different Users are reporting my equation image display sizes as wildly different as reported there.

I remain interested in the topic but am leaning back towards in-line text rendition of formulæ...

 

[Doug Kerr]

Hi, Ted,

My current issue with the "grail" is having to jump through different hoops in the various sites that I visit, not just OPF.

Indeed.

And, in DPRevived (Misago) different Users are reporting my equation image display sizes as wildly different as reported there.

I remain interested in the topic but am leaning back towards in-line text rendition of formulæ...

I understand.

Thanks for working with me on this.

Best regards,

Doug

 

[Doug Kerr]

As for me, if I should in future have the occasion to include equations (other than trivial ones) in OPF posts, I will probably just put in their pictures. Those will come out however they come out for various "visitors".

Best regards,

Doug

 

[Ted Cousins]

Hi, Ted,

Ah, so it is Mac at your place.

******

Not sure why you said that, Doug?

I use a DELL desktop PC under Windows 11. Monitor is a 24" NEC 1920x1200 px

best,

Ted.

 

[Doug Kerr]

Hi, Ted,

Not sure why you said that, Doug?

Oh, It was from something you said, and I guess I guessed wrong!

I use a DELL desktop PC under Windows 11. Monitor is a 24" NEC 1920x1200 px

We are still Windows 7 which turns out to be a continuing problem and a blessing combined! The machines are older Dell "tower" machines. On mine the display is an Asus with native resolution 1920px × 1200 px, and I run the system at that screen resolution. I run the O/S with a "magnification" of 150%, which some apps cannot deal with properly!

Thanks for straightening me out.

Best regards,

Doug

 

[Doug Kerr]

It turns out that I am a member of another forum, on an area in which I am only collaterally interested. But I am not active, and work only by receiving email messages of all traffic (and occasionally replying via email).

But recently I logged on in the "regular" way and sent a test post into which I "dropped" a picture of the quadratic formula (set for some "reasonable" display size.

I have not yet sorted out the HTML code I see when logging in again and looking at that post. I may have a further report on that later.

In any case, when I look at my post that way, it all looks just as it did in the post composition window.

In the email message I received with that post it looks as if the picture is actually encoded in some way (not displayed by way of a linked image file).

I don't know what the forum software is. This is a forum that operates under the umbrella groups.io.

Best regards,

Doug

 

[Doug Kerr]

Hi, Ted,

Another matter that may influence the results here is the display size of the body text at the "recipient".

I think that if I compose an OPF post in the usual way, there is no font size tag included. I assume that receiving browsers will render that text in some "default" size. Here, that seems to be the same size at which text explicitly tagged as "12 point" is rendered.

If that is part of the problem, a solution might be, when composing a post that is to include pictures of equations, to first select all the body text and tag it for some explicit point size.

Maybe.

Best regards,

Doug

 

[Ted Cousins]

It turns out that I am a member of another forum, on an area in which I am only collaterally interested. But I am not active, and work only by receiving email messages of all traffic (and occasionally replying via email).

But recently I logged on in the "regular" way and sent a test post into which I "dropped" a picture of the quadratic formula (set for some "reasonable" display size.

I have not yet sorted out the HTML code I see when logging in again and looking at that post. I may have a further report on that later.

In any case, when I look at my post that way, it all looks just as it did in the post composition window.

In the email message I received with that post it looks as if the picture is actually encoded in some way (not displayed by way of a linked image file).

I don't know what the forum software is. This is a forum that operates under the umbrella groups.io.

Best regards,

Doug

Hi Doug,

I notice that most if not all of your equation images are stored as attachments. In Google AI I just read this:

Alternative: Forcing Custom Image Sizes

If your goal is to let users specify exact pixel sizes manually (e.g., 400px wide), you must use the standard image BBCode tag rather than the attachment tag: in-line text, then

[IMG width="400px"]https://example.com[/IMG]

So:
(text) Equation with no width attribute:

(text) Equation above but set to 200px wide:

Can it be that simple?!

 

[Doug Kerr]

Hi, Ted,

Hi Doug,

I notice that most if not all of your equation images are stored as attachments.

Yes, the OPF software seems to do that if I just Paste an image from the clipboard into a post being composed. It makes a PNG file, then treats that as an attachment.

In Google AI I just read this:

<clip>

Very interesting. I haven't really looked at including BBCode for an image. That looks like an important avenue to follow.

I'm not sure that the OPF post regime will accept the needed BBcode tags. There are many others it will not accept.

Thanks for the lead.

Best regards,

Doug

 

[Doug Kerr]

Hi, Ted,

Here is a try of introducing a JPG file into an OPF post using BBCode:

Best regards,

Doug

 

[Doug Kerr]

Hi, Ted,

Well, there may have been some error in my entering the code! I might have had the URL to the JPG file wrong.

I will look into that presently.

The HTML back from OPF by the way looks credible!

Best regards,

Doug

 

[Ted Cousins]

Hi, Ted,

Here is a try of introducing a JPG file into an OPF post using BBCode:

Best regards,

Doug

I got that too but it was a typo

Here's yours set to 150px

Here's yours set to 150px<br />
<br />
<div class="bbImageWrapper  js-lbImage" title="Quadratic_formula-101.jpg"
		data-src="/forums/proxy.php?image=http%3A%2F%2Fdougkerr.net%2Ftransfer%2FQuadratic_formula-101.jpg&amp;hash=573794c880818490cdd5bfc0a2fb7dfd" data-lb-sidebar-href="" data-lb-caption-extra-html="" data-single-image="1">
		<img src="/forums/proxy.php?image=http%3A%2F%2Fdougkerr.net%2Ftransfer%2FQuadratic_formula-101.jpg&amp;hash=573794c880818490cdd5bfc0a2fb7dfd"
			data-url="http://dougkerr.net/transfer/Quadratic_formula-101.jpg"
			class="bbImage"
			data-zoom-target="1"
			style="width: 150px"
			alt="Quadratic_formula-101.jpg"
			title=""
			width="" height="" loading="lazy" />
	</div>

 

[Doug Kerr]

Hi, Ted,

I got that too but it was a typo

Happens to me a lot these days!

Here's yours set to 150px

Fabulous. Kudos.

Now the question is, is this better than the other way?

I note that in the actual HTML of the post (as sent to us by OPF), the structure is in fact essentially the same as if done in the other way. The BBCocde input is just a different way of "instructing" the overall setup.

Best regards,

Doug

 

[Ted Cousins]

Hi, Ted,

Happens to me a lot these days!

Fabulous. Kudos.

Now the question is, is this better than the other way?

I note that in the actual HTML of the post (as sent to us by OPF), the structure is in fact essentially the same as if done in the other way. The BBCocde input is just a different way of "instructing" the overall setup.

Best regards,

Doug

OPF HTML of my version of your quadratic equn. set to 150 px:

<img src="/forums/proxy.php?image=http%3A%2F%2Fdougkerr.net%2Ftransfer%2FQuadratic_formula-101.jpg&amp;hash=573794c880818490cdd5bfc0a2fb7dfd" data-url="http://dougkerr.net/transfer/Quadratic_formula-101.jpg" class="bbImage" data-zoom-target="1" style="width: 150px" alt="Quadratic_formula-101.jpg" title="" width="" height="" loading="lazy">

I note that CSS is not messing with the display size even though the class is "bbImage" - in other words, style="width: 150px" is taking priority for screen appearance here.

Still poking around. Fixing to compare HTML between pasting an image and loading it between BBCode 'IMG' tags with a 'width' attribute because of your the structure is in fact essentially the same as if done in the other way.

 

[Ted Cousins]

OPF HTML of my version of your quadratic equn. set to 150 px:

<img src="/forums/proxy.php?image=http%3A%2F%2Fdougkerr.net%2Ftransfer%2FQuadratic_formula-101.jpg&amp;hash=573794c880818490cdd5bfc0a2fb7dfd" data-url="http://dougkerr.net/transfer/Quadratic_formula-101.jpg" class="bbImage" data-zoom-target="1" style="width: 150px" alt="Quadratic_formula-101.jpg" title="" width="" height="" loading="lazy">

I note that CSS is not messing with the display size even though the class is "bbImage" - in other words, style="width: 150px" is taking priority for screen appearance here.

Still poking around. Fixing to compare HTML between pasting an image and loading it between BBCode 'IMG' tags with a 'width' attribute because of your the structure is in fact essentially the same as if done in the other way.

IMGs with width set 166px:

HTML:
<img src="/forums/proxy.php?image=https%3A%2F%2Fkronometric.org%2Fphot%2Ftemp%2Fyet%2520another%2520GAP.jpeg&amp;hash=cec178833e0ea816b9fa441c7d8ea427" data-url="https://kronometric.org/phot/temp/yet%20another%20GAP.jpeg" class="bbImage" data-zoom-target="1" style="width: 166px" alt="yet%20another%20GAP.jpeg" title="" width="" height="" loading="lazy">

ATTACHED with "=FULL"

HTML:
<img src="/forums/attachments/yet-another-gap-jpeg.14366/" data-attachment="full:14366" alt="yet another GAP.jpeg" class="fr-fic fr-dii fr-draggable">

For some reason, I can't copy an image and paste it here, grump. Must have misunderstood your method.

 

[Doug Kerr]

Hi, Ted,

I note that CSS is not messing with the display size even though the class is "bbImage" - in other words, style="width: 150px" is taking priority for screen appearance here.

Yes, so it seems.

So whatever problems that exist with pictures of equations in OPF posts not being displayed at a "consistent" size to various viewers would still seem to be with us when the picture is introduced as a graphic file by way of BBCode.

Still poking around. Fixing to compare HTML between pasting an image and loading it between BBCode 'IMG' tags with a 'width' attribute because of your the structure is in fact essentially the same as if done in the other way.

Yes, and that observation was made very superficially, and might have been erroneous.

Best regards,

Doug

 

[Doug Kerr]

Hi, Ted,

For some reason, I can't copy an image and paste it here, grump. Must have misunderstood your method.

Here is my method:

• Have the equation (in conventional form ) visible in some application (e.g., LibreOffice Write, LibreOffice Math, Math Magic, MS Word, etc.).

• Draw a selection marquee around the equation with a screen capture utility providing for doing that. (I use MWSnap)

• Do Copy.

• In the OPF post composition screen, put the cursor where the picture of the equation is to appear.

• Do Paste

• Size the equation picture as desired by dragging a corner handle on its bounding box.

Note that I assume that I am seeing the OPF post composition screen directly in my browser, having logged onto the OPF site through that browser.

Best regards,

Doug

 

[Doug Kerr]

Hi, Ted,

IMGs with width set 166px:

,snip.

ATTACHED with "=FULL"
View attachment 14366

Nice. I assume "=FULL" was an attribute of the BBCode IMG tag.

The "full" one reached side-to-side on my screen, regardless of the browser zoomage setting, for zoomages above a certain "step".

Thanks.

Best regards,

Doug

 

[Doug Kerr]

The discovery that the BBCode tag "IMG" was workable in an OPF post was very important. Kudos to you, Ted, for finding that and demonstrating its validity.

The question now is, does this technique give us the opportunity to circumvent what has been described as a shortcoming when inserting a picture of an equation in an OPF post using the technique I had earlier described?

That supposed shortcoming is that the display "size" of the inserted picture of an equation, say as compared to the display size of the body text of the post, is not even nearly consistent as the post is seen by various members and visitors.

That shortcoming essentially says that the style:wdth attribute that appears in the OPF post as delivered to viewers by the OPF site does not lead to the display of the picture at a consistent size with respect to the display size of the body text.

Now an advantage of the BBCode method of entry of the picture is that the value of style:size can be explicitly set, numerically, by the composer. Under the other method, the relative size of the picture can only be set by "drag-sizing" an already-inserted image. In that case, the value of style:width that the final size dictates appears in the HTML code.

I would not try and outguess other posters as to whether, for them, it would be most attractive to set style:width numerically or by dragging of an already "Pasted-in" image.

As to the supposed problem, it does not at this point seem to me that including the picture via BBCode would avert it. But then that problem is a lot like Cooties: it is hard to catch it.

In any case, it is good that we now have at least two ways to include a picture of an equation in an OPF post.

Best regards,

Doug

 

[Ted Cousins]

The discovery that the BBCode tag "IMG" was workable in an OPF post was very important. Kudos to you, Ted, for finding that and demonstrating its validity.

The question now is, does this technique give us the opportunity to circumvent what has been described as a shortcoming when inserting a picture of an equation in an OPF post using the technique I had earlier described?

That supposed shortcoming is that the display "size" of the inserted picture of an equation, say as compared to the display size of the body text of the post, is not even nearly consistent as the post is seen by various members and visitors.

That shortcoming essentially says that the style:wdth attribute that appears in the OPF post as delivered to viewers by the OPF site does not lead to the display of the picture at a consistent size with respect to the display size of the body text.

Now an advantage of the BBCode method of entry of the picture is that the value of style:size can be explicitly set, numerically, by the composer. Under the other method, the relative size of the picture can only be set by "drag-sizing" an already-inserted image. In that case, the value of style:width that the final size dictates appears in the HTML code.

I would not try and outguess other posters as to whether, for them, it would be most attractive to set style:width numerically or by dragging of an already "Pasted-in" image.

As to the supposed problem, it does not at this point seem to me that including the picture via BBCode would avert it. But then that problem is a lot like Cooties: it is hard to catch it.

In any case, it is good that we now have at least two ways to include a picture of an equation in an OPF post.

Best regards,

Doug

I've just reloaded an app. that has been long missing from my Desktop" JRuler which measures screen pixels with an always-on-top movable virtual ruler.

To my horror, I see that my earlier image posted with style = width 166px in the HTML is not that size on my screen. So back to square one for me while I investigate that.

 

[Doug Kerr]

Hi, Ted,

I've just reloaded an app. that has been long missing from my Desktop" JRuler which measures screen pixels with an always-on-top movable virtual ruler.

To my horror, I see that my earlier image posted with style = width 166px in the HTML is not that size on my screen. So back to square one for me while I investigate that.

Your browser scales the display of that that in a way that depends on its zoomage setting. It may also be effected by the "magnification" setting for your display in the O/S.)

If my browser is set to a certain "zoomage" step, the onscreen pixel width matches (closely, maybe exactly) the style:width value in the HTML code. Otherwise, not.

Best regards,

Doug

 

[Doug Kerr]

Hi, Ted,

In this post:

https://openphotographyforums.com/forums/members/doug-kerr.3466/

the gray square is set for width=202 in the HTML code sent out from the OPF site.

If my browser zoomage is set to "step 3" (of 14), the onscreen dimensions of the square are about 200 px × 200 px.

Best regards,

Doug

 

[Doug Kerr]

In this post:

Equation test - please ignore

Equation test post TP101 - please ignore This post may be edited from time to time. The quick brown foxes The quick brown fox

openphotographyforums.com

the picture of the equation was inserted using the BBCode tag IMG, no width attribute being included.

In the resulting HTML code sent by the OPF site, style:width was 187 px. I don't know where that came from. (It is not for example the pixel width of the source image file, which is 321 px.)

Best regards,

Doug

 

[Doug Kerr]

Ah, I see that one can indeed set numerically the "width" of an image that was included in an OPF post by Pasting it in place or as an "attachment".

Select the image and then use the "size" icon on the little toolbar that appears to set the style:width in the HTML code.

Best regards,

Doug

 

[Doug Kerr]

With an image in place in an OPF post for which the HTML code includes style:width=202, with the zoomage of the browser at 100%, the onscreen width of the image is very nearly 300 px.

I have a suspicion that this reflects the fact that my display "magnification" is 150%.

I will look into that in the morning (going to bed now).

Best regards,

Doug