Field Flattener, GPUSB, IR/UV Filters

[gbeal]

Bit of a clean-out.

Brand new, in box, never used. Field flattener, dead-ringer-same as my well worn AT2FF that I use. Side of barrel states "2" inch field flattener for refractor". Even the caps are the same as my AT2FF. New in the US an AT2FF will cost $150. I use mine with most refractors and IIRC used it with the GSO R/C when I had one.
Mine, AU$120 posted. ***Sold***

GPUSB. You all know what this is and what it does. It is surplus to my needs, and I haven't used it for a while. Has a "phone style cable" as well, not sure if it is the correct one, but it should work.
AU$65 posted. ****Sold****

"IR/UV cut filter On KG3". 1.25" size. Purchased when I needed an IR/UV filter for solar (PST mod). Used a couple of times, then stored. Plastic case.
AU$75 posted.

IR filter, by I believe Custom Scientific, although there is no writing on the outside. 1.25" size, and has plastic case.
AU$35 posted.

Via PM please.
Gary

[Saturnine]

Hi Gary

PM sent re GPUSB

[lazjen]

PM sent re field flattener

[gbeal]

GPUSB is sold.
Not sure about the flattener, anybody used one with an R/C that would care to suggest it does or doesn't work.
Gary

[PostalRuhl]

Hello, I have an orion ed80 and really need a field flattener.Should this be suitable for my refractor? If its still available I will take it :)

[gbeal]

Bryan.
PM'd you.
Gary

[PostalRuhl]

PM Sent ;)

[gbeal]

Flattener is sold. Just two lonely filters left.
Gary

[gbeal]

OK, time to move these, any offers?
Gary

[Djal]

Hi Gary,

re the IR/UV filter: what brand is it? and what does "on KG3" mean?

thanks
Joel.

[gbeal]

Joel.
got your PM, but feel it's as good to discuss it here anyway.
No idea, simply none, as to the "KG3" bit. I've attached a PDF, it shows the transmission curves, if you can use that.
I got it for a solar project, but didn't really use it. In as much as using it for a general webcam filter, I can't see any problems at all.
Gary

[Djal]

many thanks Gary for your prompt reply!

Well, since you have the spectral data for this filter, i don't really care about the "KG3" thing anymore :)

Based on the transmittance spectrum, I have the feeling that this filter is really oriented toward sun work as the transmittance, even in the "open" bandwidth between 400 and 700nm, is relatively low (60 to 90%) as compared to "classical" webcam IR/UV filters (close to 100% between 400 and 700nm).

Unfortunately, transmittance is critical for me as I have only a small aperture, "long" focal, refractor (80mm-900mm) and I want to do planetary imaging with a webcam :(.

Please correct me if I am wrong, I am really a beginner.

Thanks anyway for providing the relevant information, much appreciated.

Cheers,
Joel.

[gbeal]

No worries Joel. Possibly look at the Custom Scientific (I think it is anyway) one then. Cheap enough to try.
Gary