I know this is going to sound like a dumb question but.....

[Dazzyd]

Here goes. I have an Explorer 150PL and I want to get an AstroZap Baader Solar Filter for it. I'm on the FLO site, do I choose the 6" SCP or the 152mm size? I know I could make one for a lot less but being aluminium it's going to last one hell of a lot longer and if anything happened with the film I could replace it and still have the good structure to mount it on

Just not sure which to choose....... feel rather dumb right now LOL

[RikM]

I would expect the 6" SCT would be the right size. Skywatcher 150 OTA's are 182mm diameter. Best bet would be to double-check with FLO tomorrow.

[Viv]

I did the same, when I bought mine.

Am completely useless at DIY (my limit is Blue Peter cardboard house).

As Rik said, just drop FLO an email.

[sologuitarist61]

See this link, it gives a list of what sizes of aperture each filter fits.

http://stargazerslounge.com/sponsor-announcements-offers/50885-astrozap-baader-solar-filters.html

[brantuk]

I got one of these recently and like you I was unsure of the correct size. It needs to fit the diameter of the aperture not the mirror. If unsure just drop an email to any of the folks at FLO and you'll get sound advice as did I. (send the measurement of your aperture diameter to speed up the process). Good luck

[LukeSkywatcher]

It needs to fit the diameter of the aperture not the mirror.

It should fit the OD (outside diameter) of the scope/aperture, so if the aperturer is 150mm.........then you should allow a couple of mm to include the thickness of the scope tube itself.

Its a question i have pondered on many times. I think a filter of 152mm would be perfect for a 150mm scope. Nice and tight.............as a solar filter should be.

[sologuitarist61]

Always remember that the Astrozap solar filters have three screw fixings that hold the filter securely onto the tube, so it doersn't need to be a perfect fit, just the right one - see my post above for the link that gives all the sizes covered.