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Old 07-30-2023, 08:47 AM
hirondelle hirondelle is offline
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Epson Workforce Pro WF-7840

My existing Epson photo R200 is effectively dead despite my efforts to keep it going more than 10 yrs.
Decided to buy an Epson WF-7840 as, being 'old' now is a doable price & it is able to scan & print up to tabloid sized paper.
This means it can handle the A3, A4, B4, C4 etc paper sizes of European model producers.

Helpfully this ancient tech also now has plenty of clone & refillable cartridge options, the 405x cartridge being capable of up to 1100 copies (allegedly).
The unit & a set of refillable carts with enough ink for 5 refills totaled about $300, with printer on amazon. Yaaay under $250
I'm thinking it will outlast me given its specs & duty cycle

I got some cheap A3 card of 180gsm from Amazon (not photo quality but good enough for my purposes ATM). I found the weight of a sheet of A3 paper was :-
@80gsm = 10g;
@160gsm = 20g
@180gsm = c.23.3g.
The Modelik sheet is c.20g so I'm curious to see how much the 0.33g will impact any items made.

So I was ready to give this lump a test drive..
Grabbed an A3 format Modelik, scanned a color parts page, without cutting anything apart. I just opened the book & laid it on the scanner bed & closed the lid, which is sprung & clamps it in place.
Ran the scanner software, set it to 600dpi TIFF, scanned & cropped the image, & saved it to disk.
A full colour 600dpi A3 TIFF is about 200mb I found. TIFF will store a lot of data/information & give a good render of the scanned image.

I used irfanview (free) to view & give me a color count of the images.
When viewing a scan, it is normal, in my experience, to see a color cast, a greying of what should be white. This is due to the fact that paper cannot reflect 100% of the directed light I believe.
Luckily with software, you can use the white eyedropper tool to set the white point in e.g. Gimp, Inkscape & Photoshop.
I tend to go for a mid-range gray part of a scan with the dropper, usually near a corner, as taking the darkest or lightest part as sample will skew the other color bands.
The resulting image will have the whole image reset to that value for white, a bit like taking a filter off of a lens. This can give you a LOT more colors & will be a much better print. Compare the color counts & it can be a significant increase e.g. 500k to 550k+ colors.

I sent the image to print, ensuring that it was centered & printed according to DPI. I was told it was going to be outside the margins, but being able to see it was within the size of the sheet (via print preview) I pulled the trigger on it.
You do need a GFX program like GIMP or photoshop that will send high quality code to the printer & ensure the image will be output correctly. Less technically advanced stuff will print but you can get all sorts of issues with what & where it prints. Particularly irritating things like color aberrations & auto margin 'printing' - meaning the prog deliberately whites out where it thinks the margin should be (chopping parts), occur with less capable software.

At this point it is real useful to have a caliper/micrometer. This allows you to compare mm for mm, output to original. I do this at various places, width, height & diagonals need to be cross checked randomly top, middle & bottom of sheet. You can do it all of course, but I chose about 6 things at random & all were 100% the same dimensions.
Big relief as that meant it was all set up as req'd & did what I needed!

Here is the result. The deficit in paper quality & it not being a $50k+ printer are obvious but not terrible (& may be solvable with more eyedropper tinkering for the black & mid-range tones & / or a varnish coat). Now all I need to do is actually make sth.
Attached Thumbnails
Epson Workforce Pro WF-7840-clipboard_data.jpg  

Last edited by hirondelle; 07-30-2023 at 09:00 AM.
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