Photographic filter comparisons...???
Posted 02 July 2013 - 04:15 PM
Does anyone know where I could find some photographic comparisons of various filters (UHC, O-III, NarrowBand, ect.) I.E., Pictures of the same object without filters, then with filters? I've seen Jim Thomson's EXCELLENT analysis, but am looking for something more 'visual' and 'graspable' for some students.
This is for video camera use and outreach.
Posted 03 July 2013 - 07:32 AM
Not the answer you are looking for...
Astro targets have various emission (or absorption) spectrum. Various filters exist to adapt for different needs. Different people will have different viewing conditions as well.
Your original request is too broad a topic.
(This is like comparing a gasoline sedan with brand X oil filter with a diesel train engine equipped with brand Y filter...)
Most of the filter reviews I have seen have been:
comparing a specific type (e.g., O III filters from various makers) onto few astro targets.
Knowing your own specific need (e.g., combat severe light pollution for most astro objects, need to see horsehead, ...) to narrow down the search perimeter would be a good start.
Posted 03 July 2013 - 09:34 AM
Over the years I've seen a few comparisons done and results posted on personal websites. If you poke around using a search tool (searching on the name of a particular filter) you should find a few of them. In my experience it's rare to find good comprehensive comparisons. Most folks don't spend too much time with comparable filters, they tend to pick one that works better for them and sell the others.
Posted 03 July 2013 - 09:50 AM
I know, and I agree. What I'm looking for are some general pictures, showing something like "this is M42 without any filters, and this is what it might look like with an OIII or a Astronomik UHC, or a typical LPR filter, given normal light polution".
Also looking for examples of general filters used on emission and reflection nebulae, as well as the effects on globulars and galaxies.
I have found a few pictures, but was hoping to find more and better examples. As I said, these are for giving students a general idea of how filters work (when they ask).
I am working on some comparitive shots myself, but I've had so few clear nights, it makes it hard.
Plus, my 'cloud filter' isn't working for *BLEEP*....!
Have a great one!
Posted 03 July 2013 - 01:50 PM
That is exactly what I was looking for.
I've gone through Most of Jim's articles, but I must have missed this one.
Thanks, and have a great day!