Hi everyone!
I'm new to astronomy but I have taken some ad hoc star photos while on holiday in NZ with my D700 and a Tamron 17-35mm. Generally used <30s exposures as no tracking mount available.
The coma at field edges was horrible but the stars were more brilliant than I'd ever seen in Singapore. Never knew about stacking short exposures
I'd like to ask if a light pollution filter when used in Singapore will yield similar results (a lot more stars than visible through eyeball in a dark background) or will it just be a few stars showing in a hazy background?
Don't think will make the plunge to buy a telescope just yet though, funds limited so intend to use stock lenses. Having said that, one of them is effectively a 3in. achromatic refractor with 4x power *grin*
Newbie - Light Pollution filter?
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Depending on what filter you use. I would suggest the orion one, it doesn't cost a bomb and yield quite satisfying results. But if you wish to do astrophotography, you will need to go narrowband or get a more extreme LPR filter. O3 filters also allows you to see dim stuff, such as planetary nebulas, otherwise invisible when no filters are used. LPR filters work by blocking out specific wavelengths of light, particularly those emitted by mercury and sodium vapour lamps, and letting all other wavelengths trough. From personal experience, it does improve what I see a little and even adds a little more contrast, but don't be too overly optimistic to expect to see galaxies and anything above magnitude 8.
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Hi Chris, yes I understand that part already. Just asking if there are different threads for refractor and SCT backs. ie the physical construction of the filter threads?
Orion 1.25in. SkyGlow Broadband Telescope Filter #05660
Orion SkyGlow™ Broadband Filter, 2"
Orion Schmidt Cassegrain SkyGlow Broadband Filter #05658
Orion Schmidt Cassegrain SkyGlow Broadband Filter #05658
On telescope.com, there are some filters with Schimidt Cassegrain on it, some don't have.
Those for AP I can guess, better transmission for the parts where the CCD chips are more sensitive or something.
Orion 1.25in. SkyGlow Broadband Telescope Filter #05660
Orion SkyGlow™ Broadband Filter, 2"
Orion Schmidt Cassegrain SkyGlow Broadband Filter #05658
Orion Schmidt Cassegrain SkyGlow Broadband Filter #05658
On telescope.com, there are some filters with Schimidt Cassegrain on it, some don't have.
Those for AP I can guess, better transmission for the parts where the CCD chips are more sensitive or something.
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Hi,
The best is to buy those 2" or 1.25" version as you still can use them on other type of scope. Those SCT version use SCT thread which design to screw directly behind the SCT OTA (infront of the visual back).
Between 2" and 1.25" version, get the 2" version if you use 2" diagonal and got the $$.
By the way, IMHO, if you only going to get one filter for visual use, get the UHC narrowband filter.
Have a nice day.
The best is to buy those 2" or 1.25" version as you still can use them on other type of scope. Those SCT version use SCT thread which design to screw directly behind the SCT OTA (infront of the visual back).
Between 2" and 1.25" version, get the 2" version if you use 2" diagonal and got the $$.
By the way, IMHO, if you only going to get one filter for visual use, get the UHC narrowband filter.
Have a nice day.
Yang Weixing
"The universe is composed mainly of hydrogen and ignorance."
"The universe is composed mainly of hydrogen and ignorance."
There will usually be threads for filters in most astro CCD cameras, such as the Orion starshoot pro 2. Again, Depends on what refractor you getting. Even if it don't come with threads, you can always attach an adaptor/ diagonal with threads.
For astrophotog use, I would personally prefer 2" filters. As weixing pointed out, you can use it on most scopes and it will never affect your field of view.
As for visual filters, get the 1.25". Just screw it on the threads on any eyepiece.
For astrophotog use, I would personally prefer 2" filters. As weixing pointed out, you can use it on most scopes and it will never affect your field of view.
As for visual filters, get the 1.25". Just screw it on the threads on any eyepiece.