Howie Glatter

[martin_h]

Has any one got one with the concentric rings attachment? I have just purchased one and I don't know if its ok or not... The rings are not the same thickness, see photo

[fwm891]

Hi Martin - mine was like that with the ring generating filter. It's because the laser source is not circular, more rectangular so produces a combination of wide and narrow ring sections at 90° to each other 

[martin_h]

Well that's ok then

[Skipper Billy]

I appreciate that Francis had the same but I didnt.

The rings were perfectly concentric.

How will you be able to collimate with the rings so far out of whack ??

I would respectfully suggest that there is not right there.

I will see if I can find a photo of my rings.

[Jason D]

That does not look right. I would ask for a replacement. Here is mine. 

Don't mind what I was trying to do in these photos -- just check the uniformity of the rings.

[fwm891]

OK perhaps mine was out too without realising it. Having used laser diodes before on other kit I knew the laser beam was rectangular.

Perhaps Martin should remove all the filters and examine the 'spot' generated by the laser itself.

[Jason D]

I believe the issue reported by the OP could be (and I am speculating) due to the holographic optical piece mounted on its metallic casing at an angle.  Referring to the OP's original photo, note how the pattern looks OK along the 2:00<->8:00 line but looks at its worse along the 11:00<->5:00 line.

Jason

[martin_h]

15 hours ago, Skipper Billy said:

I appreciate that Francis had the same but I didnt.

The rings were perfectly concentric.

How will you be able to collimate with the rings so far out of whack ??

I would respectfully suggest that there is not right there.

I will see if I can find a photo of my rings.

I will have a word with the good people at FLO

[Skipper Billy]

I haven't kept the photos of my vain attempts to collimate an RC but the rigs when shone onto a flat wall were perfectly concentric and uniform thickness.