Scale problem when printing to PDF

I have been trying to cut some business card style items from card stock using the camera to line up the printed stock with the cutting items, but no matter how many times I calibrated the camera it never overlapped.
I eventually found a problem in that the PDF file is approximately 47% of the size of the original. If I increase the size of the print objects by 200% as I had been doing to make them fit they still come out at 95% of the correct width and 96% of the correct height.
I haven’t been able to find any settings that I could have messed with so can you give me a hint as to what is wrong?
Running 0.9.24 on MacBook Pro with Ruida controller

Edit:By experimentation I have found that scaling up 198.8% produces a print that is the correct size. Unfortunately I can still not get the camera image to align with the design in LB. I have a screen capture but there doesn’t seem to be a way to attach to this message.

You can also drag and drop or use the OS Copy/Paste to place the image in-line as you’d like.

By altering the scale factor the page is printed correctly but the same boxes in LB don’t match the image as you can see. The camera was completely re-calibrated once again.
Anyone got any ideas as to why the PDF is coming out half size and when corrected it is not in alignment with the original?

Are you printing from LightBurn? I’m confused as to what you’re actually doing.

If you’re using the “Print” function from LightBurn, anything that is larger than your page will be scaled to fit - it’s intended for sending client proofs, and the scaling is automatic and can’t be disabled at the moment.

Hi Oz, what is being printed is an A4 page (210x296mm) which fits the bed profile of 400x400mm so it is within the LB bounds. I have created a mock-up of the card layout which should exactly match the layout of the printed items when they arrive. I found that when I tried to print from LB it was as I said earlier printing the PDF at about 1/2 size which I managed to compensate for by scaling it up so it is correctly laid out as per the printed sheet but when placed on the bed and captured with the camera there is a huge discrepancy between the LB design and the screen capture.
The boxes in LB are the only things that will be cut, the rest is to help with the alignment. The size of the box when printed is exactly the size of the box in the design but when placed under the camera there is a difference. Does that make sense?

Is the material surface at the exact same height as when you ran the alignment markers?

Basically the distance from the material surface to the camera can’t change - if you focus using the Z bed, you set the focus height first, then take your capture. If you use an adjustable lens tube to set the focus, you can’t do that or it will affect the camera alignment.

Absolutely. I also ran a full camera alignment just before as well. I’m assuming that nobody else has seen this before.

From what I can understand you are printing out the PDF and then taking a photo of the printout for use in Lightburn. You could try not using the camera but create a new PDF @ 100% from the 47% PDF. You can check the result with the Measuring Tool found under Edit - Analysis in Adobe Reader II. Now take a Snapshot (Edit - Take a Snapshot)by highlighting the page and save the result as a .jpg file which can now be used by Lightburn. I’m no expert but I hope this helps.

Thanks John but that’s not quite what is happening. I have a friend who collects vintage outboard motors and wanted small file cards to keep details on. It was a simple matter to design the form in LightBurn and the idea was to print ten copies on each A4 sheet then cut them on the laser. However when you print in LB the PDF comes out scaled down to 50% which seemed to be wrong. Why not print at the correct scale? If the idea is to use the print as a way of showing it to a customer then surely it should be the correct size?
Hence my putting in the question.

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