J Tech Hi Res lens or Ebay Lens for 2.8w

I have had my laser for about a month and I cant seem to get the focus right at all. I have tried everything and nothing seems to work. It will burn MDF like crazy and barely marks basswood. It must be the lens is my guess. As close to focus as I can get at 3" to heat sink looks like a square at 45* with the right side being a crisp thin line, everything to the left is lit like a soft light. I tied to find a way to take a pic but no luck. So the question is Ebay lens or Hi res lens as a replacement?

Not all wood will char or mark look to see if it is cutting into the wood if so then it is working just fine. sometimes you can apply a light stain to the wood and then it may leave a acceptable mark. A lens upgrade is well worth the money as it gives the benefit of a finer beam and can allow you to up your feed rate But alas some wood just will not mark well. This is the lens I use https://www.ebay.com/itm/445nm-450nm-462nm-465nm-Blue-Glass-Collimating-Lens-M9P0-5-10-Metal-Frame/261157555202?_trkparms=aid%3D111001%26algo%3DREC.SEED%26ao%3D1%26asc%3D50425%26meid%3De41567f3ca1a4aefba15af1bfcd002b0%26pid%3D100675%26rk%3D1%26rkt%3D15%26mehot%3Dpp%26sd%3D261157555202%26itm%3D261157555202&_trksid=p2481888.c100675.m4236&_trkparms=pageci%3A0d7ac59e-2f7c-11e8-a90f-74dbd1805da5|parentrq%3A58ba9f671620ad4b1345070afffe7a79|iid%3A1
here is a unfocused before and after lens upgrade. You can see the difference between the 2 at the same setting
old
new

Not even close to what mine looks like.

Don’t take this wrong cause some tend to understand me but after you set your height to 3 inches did you do the final focus by screwing the lens in or out. I have also heard of lenses installed backwards from the manufacturer.

I took the ring off and flipped over install ring on other side just to see. How it came was as good as it gets. Maybe a bad lens.

Not the same, but different.

Lots of variables. Camera lenses are usually multi-element anti-reflective coated lenses which eat up some power and semi-conductor camera capture devices are not as sensitive as eyes.

But having said that, yes taking pictures of laser light can fry a camera’s sensor. Just a matter of how much power actually gets to the sensor.

in some cases yes and is why I keep my older cellphones to do video and photos instead of using my $$$ camcorder. If I remember next time I fry a row of pixels i will post a pic. Makes you more aware of what can happen when you dont wear your ppe.

I agree with what you say. I was looking at the question in a different manner as in the rods and cones within the eye are kinda like pixels.