I know there are cheap and expensive filters available, just as a Rolls Royce is better than a Ford Focus, but............ they are still cars, legal and get you from a-b
Filters. There are these
https://www.ebay.co.uk/i/183268614612?chn=ps
and these
https://www.widescreen-centre.co.uk/ida ... ilter.html
and these
https://www.widescreen-centre.co.uk/baa ... 317mm.html
etc
I have the first one, (a) is it OK ?, (b) would the Baader be better and if so how, (c) if the one I have is not any good how will I know. What would you suggest for in front of the diagonal with a Quark Cromo as an IR blocking (heat) filter
Many thanks indeed
Sub Aperture ERF Options For Quarks
Sub Aperture ERF Options For Quarks
Just for info, if I ever come over as "blunt" or upset it is not intentional, I am AUTISTIC, I have Aspergers, and ADHD, Autism, so my apologies if I ever sound, unintentionally confrontational. Thank you
Esprit 120mm triplet refractor
Celestron Evolution Edge HD 8"
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Esprit 120mm triplet refractor
Celestron Evolution Edge HD 8"
72mm Ed Skywatcher for Solar
SkyTee 2
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Gitzo Systematic Series 5
ASI 178MM
Daystar Quark Ha
WO Binoviewers
Many eyepieces 2"
- krakatoa1883
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Re: I know there are cheap and expensive
Hi
Let's look at the transmission curves of all these filters
Svbony IDAS Baader Neodymium Outside the range 400 (450) - 700 nm they all look about the same, with some differences which are not relevant for H alpha observing, so if the declared curves are reliable there would be no reason to prefer one over the others.
I personally (just my opinion) would not use the cheapest one, filters shall not only block the undesired wavelengths but shall also be finely polished and very well coated, so I would take only the best available ones.
In front of my Quark I normally use a L-2 Astronomik UV/IR cut which has the following transmission quite similar to the filters above. I sometimes use also the Baader equivalent (this one) or even a deep sky H-alpha filter.
Hope it helps
Let's look at the transmission curves of all these filters
Svbony IDAS Baader Neodymium Outside the range 400 (450) - 700 nm they all look about the same, with some differences which are not relevant for H alpha observing, so if the declared curves are reliable there would be no reason to prefer one over the others.
I personally (just my opinion) would not use the cheapest one, filters shall not only block the undesired wavelengths but shall also be finely polished and very well coated, so I would take only the best available ones.
In front of my Quark I normally use a L-2 Astronomik UV/IR cut which has the following transmission quite similar to the filters above. I sometimes use also the Baader equivalent (this one) or even a deep sky H-alpha filter.
good question with no easy answer, it would require to determine the transmission curve.
Hope it helps
Raf
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My solar images and reports with articles on solar equipment
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Re: I know there are cheap and expensive
There is no free lunch the saying goes :-)
Christian Viladrich
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Re: I know there are cheap and expensive
Hi
I have two of the sVboney a beloptic and the baader have also tried the baader 35nm all give the same results for solar.
The beloptic is on KG3 glass so may have more protection.
Personally I would use the one you already have and save your money to put towards a D-ERF.
The quark has a good blocker all the UV/IR is doing is protecting it from degrading a D-ERF protects everything and removes tube currents that will result in better seeing.
I have two of the sVboney a beloptic and the baader have also tried the baader 35nm all give the same results for solar.
The beloptic is on KG3 glass so may have more protection.
Personally I would use the one you already have and save your money to put towards a D-ERF.
The quark has a good blocker all the UV/IR is doing is protecting it from degrading a D-ERF protects everything and removes tube currents that will result in better seeing.
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Re: Sub Aperture ERF Options For Quarks
For me it's like what Christian says. My experience is that the cheaper option stops working at some point before you anticipate.
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Re: Sub Aperture ERF Options For Quarks
Hi
You could try this at the front it would stop quite a bit of heat buildup in the scope
https://www.ebay.co.uk/itm/B-W-UV-IR-Sp ... 1438.l2649
The graph seems to fit the bill and as far as I can remember B+W filters are polished 1/4 wave much better than most camera filters.
Just a idea of another option.
You could try this at the front it would stop quite a bit of heat buildup in the scope
https://www.ebay.co.uk/itm/B-W-UV-IR-Sp ... 1438.l2649
The graph seems to fit the bill and as far as I can remember B+W filters are polished 1/4 wave much better than most camera filters.
Just a idea of another option.
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