BANDING issue. ONLY with photos...hmmmmm

[bruce edwards]

I did a search 1st and saw a lot about banding...but didn't see anything about my situation. Text and graphics on aluminum comes out perfect.
A photo on the same piece of aluminum has a lot of banding. Why wouldnt the entire piece have banding? Only the photo. Is it possible the aluminum
itself is the problem? I got it from Lasersketch so I wouldn't think that would be it. I did the same photo on a business card from Chewbarka and there
was no banding on the photo. Grasping at straws....thank you

1st pic is close up of banding on 8x11 inch aluminum
2nd pic is the whole sheet of aluminum (no banding on the text)
3rd pic is same picture on 3.5x2 inch business card (no banding)

213408213409213410

[Dee Gallo]

Did you resize the photo after processing it? That will do it.

[Ross Moshinsky]

What Dee said.

Also: Run the text. Then run the photo. Report back.

[bruce edwards]

Ah...maybe that's it Dee. Because it only happens sometimes....I'm still learning. ;) I'll give it another shot and hope it works...130am here....I'll do it tomorrow. Thank you

[bruce edwards]

I started all over and made the pic of the people and pic of knife the proper size before processing them. I am still getting banding.
OMG this is so much time on this...and not worth it hehe But I have no choice now....any other ideas? I have cleaned, lubed everything
according to the manual....
Heres a pic of completed latest attempt. I also ran the text 1st, then the photo. The top photo is the knife NOT inverted-no banding.
Bottom photo is same image, same settings, all I did was invert it as I have to, to engrave on aluminum. I'm only getting the banding
when I invert the image?!?!?!?! Why??? Thank you if anyone knows...

(also I didn't keep engraving as at this point I'm just trying to get rid of the problem, that's why only partial pic of knife)

[Dan Hintz]

I can't understand that picture... it looks like there's a reflection, as if you're taking the pic through a piece of glass.

[Chuck Stone]

The top photo is the knife NOT inverted-no banding.
Bottom photo is same image, same settings, all I did was invert it as I have to, to engrave on aluminum. I'm only getting the banding
when I invert the image?!?!?!?!

If they are the same image, you wouldn't get banding on one of them, because the laser
isn't DOING anything on most of the image. And banding is tough to see in fine details.
You can see it better in larger blocks of solid color.

I'm going to take a guess (because I don't know your laser and I'm not a tech)
But you might want to check the roller assemblies for the Y axis. I don't know if
your laser has a solid rail or not .. but there should be rollers that move the Y rail
from front to back. They could be dirty or the rail itself may have debris on it.
(but since it is a regular spacing I'd look at the rollers themselves, or the bearings
inside them, if any) If these rollers are fouled, then your Y rail will actually move UP
as those rollers roll over the crud, bringing your head slightly out of focus and slightly
reducing the beam's power at the focal point.
OK, that's my WAG.

[Bill Cunningham]

make sure the photo is the same DPI as the engraving.. I.E. A 300 dpi photo etched at 500 can have a banding problem.. You don't get it on the text because that's not a halftone image