Dismiss Notice
New Cookie Policy
On May 24, 2018, we published revised versions of our Terms and Rules and Cookie Policy. Your use of AstronomyConnect.com’s services is subject to these revised terms.

Planetary Filter Tests

Discussion in 'General Astronomy Chat' started by BillP, Jul 1, 2020.

Planetary Filter Tests

Started by BillP on Jul 1, 2020 at 1:20 PM

7 Replies 347 Views 1 Likes

Reply to Thread Post New Thread
  1. BillP

    BillP Well-Known Member

    Joined:
    Aug 3, 2015
    Posts:
    165
    Trophy Points:
    343
    Location:
    Vienna, VA
    A few mornings ago I used my TSA-102 observed Jupiter and Saturn for 3 hours testing a variety of filters I have. Seeing steady. Contrast not optimal as a lot of moisture in the air. Used the 14XW eyepiece on a TV 2.5x Powermate for effective 5.6mm (146x). Filters were rapidly compared against each other by placing them on the eye lens (why I chose a 20mm ER eyepiece). A day after that I observed the Moon to test the filters on that target. Waiting for Mars to come out behind trees in my yard to test them on that planet. Below are the results so far.

    JUPITER

    Orion Skyglow -- Did not like; Color cast too unnatural and distracting (blue); Some details lost due to dimming of view; Did not like.

    Baader Contrast Booster -- Favorite for Jupiter; Minimal apparent color shift (very slightly warmer tone); Dimming slight to none; Enhanced contrast for NEB and SEB making them easier to see and really accentuated the irregular borders of the NEB; Some belts above NEB and below SEB not apparent with no filtration were apparent with this filter; White region between two belts below SEB highly accentuated and brighter with this filter.

    WO VR-1 Violet Rejection -- NEB and SEB appeared more contrasted; Color shift towards yellow was too strong on Jupiter making the view distracting; Made planet seem brighter losing some subtle details; Did not like.

    VERNONscope #30 Magenta -- Did not like; Color shift towards magenta was too strong on Jupiter making the view distracting; No obvious enhancement to details; Did not like.

    Omega Optical Color Enhancing Filter -- Moderate color shift (ruddy brown); Moderate dimming made more difficult to see some of the more subtle features with the 4" Apo; Did not like.

    Baader Semi-Apo -- TBD; Have not received yet.

    Baader Moon & Skyglow -- TBD; Have not received yet.​


    SATURN

    Orion Skyglow -- Did not like; Color cast too unnatural and distracting (blue); Some details lost due to dimming of view; Did not like.

    Baader Contrast Booster -- 2nd favorite for Saturn; Minimal apparent color shift (very slightly warmer tone); Dimming none to very slight; Enhanced contrast for Cassini Division and atmosphere bands and polar region making them easier to discern; Some band striations in atmosphere not apparent with no filtration were apparent with filtration.

    WO VR-1 Violet Rejection -- 1st favorite for Saturn; Minimal apparent color shift (yellow); No apparent dimming and seemed to brighten planet slightly; Enhanced contrast for Cassini Division and atmosphere bands and polar region making them easier to discern; Some band striations in atmosphere not apparent with no filtration were apparent with filtration.

    VERNONscope #30 Magenta -- Did not like; Color shift unnatural and distracting (magenta); Did not like.

    Omega Optical Color Enhancing Filter -- Moderate color shift (ruddy brown); Moderate dimming made more difficult to see features with the 4" Apo; Did not like.

    Baader Semi-Apo -- TBD; Have not received yet.

    Baader Moon & Skyglow -- TBD; Have not received yet.​


    MOON

    Orion Skyglow -- Did not like; Color shift too unnatural and distracting (blue); Some details lost due to dimming of view; Did not like.

    Baader Contrast Booster -- Tied favorite for Moon; Minimal and non-distracting color shift (very slightly warmer tone); Minimal dimming; Subtle shades in lunar maria and lava flows enhanced; Could not decide if liked this or the VR-1 as favorite on Moon.

    WO VR-1 Violet Rejection -- Tied favorite for Moon; Moderate color shift (yellow) but not distracting on Moon; No dimming, in fact made object appear brighter; Subtle shades in lunar maria and lava flows enhanced; Could not decide if liked this or the Baader Contrast Booster as favorite on Moon.

    VERNONscope #30 Magenta -- Did not like; Color shift unnatural and distracting (magenta) ; Did not like.

    Omega Optical Color Enhancing Filter -- Liked better than #30 Magenta; Overall some enhancement of maria and lava flow shading but not significant; Moderate color shift (ruddy brown); Moderate dimming; On the fence whether like it or not for the Moon.

    Baader Semi-Apo -- Testing TBD; Have not received yet.

    Baader Moon & Skyglow -- TBD; Have not received yet.​


    MARS

    Testing TBD; Still behind trees for me.​
     
    Orion25 likes this.
  2. Orion25

    Orion25 Well-Known Member

    Joined:
    May 23, 2016
    Posts:
    1,351
    Trophy Points:
    113
    Location:
    Georgia
    Great report, Bill, I, too, am waiting for Mars to come up at a decent hour to try out my filters :)
     
  3. BillP

    BillP Well-Known Member

    Joined:
    Aug 3, 2015
    Posts:
    165
    Trophy Points:
    343
    Location:
    Vienna, VA
    Update #2 ....

    Wanted to spend some dedicated time with the Moon tonight. Used the TSA-102 observing the Moon for 3 hours with MaxBright-II Binoviewer. Seeing steady with crisp steady views up through 210x (did not bother to try to go higher). Used 24 ES68 pair and 12 BST Starguider + AT Paradigm pair without OCA, 1.6x OCA. and 3.1x OCA. Depending on the configuration magnifications were approx: 35x, 50x, 70x, 100x, 210x.

    MOON

    Views were spectacular with almost a full Moon with Schröter's Valley nicely side lit near the terminator. Examined various features without filter, with Baader Contrast Booster, with WO VR-1, and with both these filters stacked.

    The VR-1 gives the Moon a slight yellow tinge but not strong so it still looks quite natural. The Contrast Booster also gives the Moon a fairly subtle cast but more in a yellow-green to my eye. When both filters are stacked the green comes out just a little stronger. Regardless of configuration though everything looked natural enough.

    Both the Contrast Booster and VR-1 separately brought out shadings in the Maria better than with no filter. The VR-1 also accentuated the very bright white spots/features and overall made the view feel like it was brighter. The Contrast Booster tended to instead accentuate the darker regions and shadings showing them better. Overall I felt the Contrast Booster also made fine details just a little more evident. If I had to choose only one it would be the Contrast Booster.

    What was nice though is when they were stacked, especially if the entire Moon was visible in the FOV. With both stacked the subtle shadings in the Maria showed much more details. So patches that looked uniform in either filter individually, showed a lot of variation in shades when these were stacked. Together they really brought out a wealth more details in the shadings of the maria and lava flows across the Moon, so much so that I found it fascinating to stay at the lowest magnification of 35x as the intricate shadings were just so interesting to see like this. And with the comfort of binoviewing I was probably on target at 35x for more than 30 minutes or more straight before ending the observing session. Was a real treat using both these filters stacked in the binoviewer! They will definitely be going out together for the Moon again [​IMG]
     
  4. Ed D

    Ed D Well-Known Member

    Joined:
    Jan 12, 2017
    Posts:
    524
    Trophy Points:
    63
    Location:
    Sunny South Florida
    Good information on the filters you tried. Stacking filters can often yield favorable results. Sometimes the order in which they are stacked have different effects. When I was using achromats I used to stack a yellow #8 and Baader Neodymium. The #8 faced the field end to filter out the unwanted out of focus wavelengths, the Neodymium filter behind it to to get rid of the slight yellow cast. The resulting image was amazingly sharp with good color balance. It didn't work as well if the stacking order was reversed.

    I'm looking forward to your test results of the Baader Neodymium filter (M&SG) on the planets and moon.

    Ed D
     
  5. BillP

    BillP Well-Known Member

    Joined:
    Aug 3, 2015
    Posts:
    165
    Trophy Points:
    343
    Location:
    Vienna, VA
    I had not thought of that but it makes sense I guess. Don't know how I stacked them.
     
  6. BillP

    BillP Well-Known Member

    Joined:
    Aug 3, 2015
    Posts:
    165
    Trophy Points:
    343
    Location:
    Vienna, VA
    FINAL UPDATE...

    Condensed down the field to the best of best performers, plus included a few Rosco filters not previously mentioned as was out this early this AM watching the GRS and a moon transit on Jupiter before observing more of Saturn and Mars and the Moon and testing a variety of different Rosco green, yellow-amber, magenta, and green filters. Note that in my filter numbers if preceded by a "W" it means the Wratten equivalent in the common color glass filters for astronomy, if it is preceded by an "R" it means it is a Roscolux Gel filter which are very inexpensive (a few dollars for a gel sheet) to get and just cut to fit an empty filter housing.

    Overall though, you will notice that the Baader Contrast Booster took top or near top positions many times. So if you want to simplify your observing life that one filter worked very well across all the targets tested.

    A Word of Caution -- All these test results where when viewing the planets (not the Moon) at a magnification that produced a 0.5mm Exit Pupil -- this was 200x in my TSA-102 Apo. Realize that when using larger apertures at the same magnification, the Exit Pupil will be much larger so the planet will be much brighter and the filter's impact may not be the same or extensible to larger apertures. As example, a 10" Dob at 200x produces a 1.28mm exit pupil and the view is 6.5x brighter! So more aggressive filters or combination with a neutral density filter or use of higher magnifications may be necessary to replicate results. But for us smaller aperture aficionados, below is what you are likely to see.

    MOON

    Baader Contrast Booster -- Favorite for Moon. Minimal and non-distracting color shift (very slightly warmer tone); minimal dimming; subtle shades in lunar maria and lava flows enhanced.​

    Baader Contrast Booster + VR-1 Violet Rejection -- Even Better for Moon. The VR-1 gives the Moon a slight yellow tinge but not strong so it still looks quite natural. The Contrast Booster also gives the Moon a fairly subtle cast but more in a yellow-green to my eye. When both filters are stacked the green comes out just a little stronger. Regardless of configuration though everything looked natural enough. With both stacked the subtle shadings in the Maria showed much more details. So patches that looked uniform in either filter individually, showed a lot of variation in shades when these were stacked. Together they really brought out a wealth more details in the shadings of the maria and lava flows across the Moon. NOTE - Substituting the W8 Yellow (83%) for the VR-1 might have similar results.​

    MARS

    R9 Pale Amber Gold (74%) + Contrast Booster -- Stacked Filters that Outperformed all Single Filters. Overall excellent job at darkening maria; highlighting polar cap and limb haze; keeps colors reasonably within what one expects for Mars. Takes #1 position due to maria being darkened and detailed best over all single filters tested and this stacked set outperforms all the single filter options I tested. NOTE - the R9 Pale Amber Gold (74%) + W12 Deep Yellow were very close if you cannot afford the Contrast Booster. https://www.bhphotovideo.com/c/product/43705-REG/Rosco_RS0911_09_Filter_Pale.html

    R3408 Roscosun 1/2 CTO (74%) -- Favorite for Mars. This is a color conversion "warming" gel filter that shifts the color temperature from 5500 deg K to 3800 deg K. It's closest equivalent in Wratten filters would be the W81C Yellowish (72%) warming color compensation filter. Colors stayed neutral; brightened deserts and plains; darkened the maria nicely. Contrast Booster is my second choice as a single filter for Mars -- while the Contrast Booster darkened maria just a little more, it also dimmed the overall view a little more than this filter and did not brighten the polar cap as much as this one either. Overall quite an outstanding filter for Mars! Inexpensive ATMed substitute for the Contrast Booster. https://www.bhphotovideo.com/c/product/44201-REG/Rosco_RS340811_3408_Filter_RoscoSun.html

    Baader Contrast Booster -- 2nd Favorite for Mars. Slight color shift on Mars from expected hues, but not distracting; most notably the maria were darkened; the polar cap and limb haze were brightened also; overall extremely pleasing and a top performer for all general features on Mars.​

    R9 Pale Amber Gold (74%) -- Inexpensive 2nd Favorite for Mars. 74% transmission. This was the surprise of the evening. Unexpectedly, this filter tied with the Contrast Booster for overall best single filter of all the other filters tested! Maria were darkened nicely (not quite as dark as the Contrast Booster); polar cap and limb haze brightened to show very prominently; color shift was such that all the colors on Mars really looked great. Excellent performer! https://www.bhphotovideo.com/c/product/43705-REG/Rosco_RS0911_09_Filter_Pale.html

    W58 Green (24%) -- Special Case for Mars Polar Cap. Cast Mars in unnatural green hues and dimmed view given its 24% transmission. I was not expecting this filter to be of any benefit, however it ended up providing one of the more memorable views of the observation session. This filter revealed a crisply defined very dark boarder around the polar cap, which was still quite bright. So the contrast of these two features really made the polar cap extremely pronounced, so much so that it looked like a half "bulls eye" on the pole of the planet -- so an excellent single feature filter. Quite exciting to see these features so starkly portrayed -- so nice that made the green hues not distracting at all! NOTE - curious to see how the W56 Green (53%) compares.​

    JUPITER

    Baader Contrast Booster -- Favorite for Jupiter. Minimal apparent color shift (very slightly warmer tone); dimming slight to none; enhanced contrast for NEB and SEB making them easier to see and really accentuated the irregular borders of the NEB; equatorial Belt not seen unfiltered was revealed; some belts above NEB and below SEB not apparent with no filtration were apparent with this filter; white zones between two belts below SEB highly accentuated and brighter with this filter.​

    R304 Pale Apricot (79%) -- Recommend for Jupiter. North Pole better defined, moon transits definition excellent; GRS retains some of its red-pink coloration; belts better contrasted; some hue cast to planet but not off-putting; overall enjoyed how it enhanced the view. https://www.bhphotovideo.com/c/product/44080-REG/Rosco_RS30411_304_Filter_Pale.html

    SATURN

    WO VR-1 Violet Rejection -- 1st Favorite for Saturn. Minimal apparent color shift (yellow); no apparent dimming and seemed to brighten planet slightly; enhanced contrast for Cassini Division and atmosphere bands and polar region making them easier to discern; some band striations in atmosphere not apparent with no filtration were apparent with filtration. NOTE - a W8 filter might produce very similar results.​

    Baader Contrast Booster -- 2nd Favorite for Saturn. Minimal apparent color shift (very slightly warmer tone); dimming none to very slight; enhanced contrast for Cassini Division and atmosphere bands and polar region making them easier to discern; some band striations in atmosphere not apparent with no filtration were apparent with filtration.​

    R304 Pale Apricot (79%) -- Highly recommend for Saturn. Not as aggressive as R302 Pale B'stard Amber (88%) with a hue cast to planet that was very minor; brought out bands quite prominently; polar details and Cassini contrast all improved. Inexpensive ATMed substitute for the Contrast Booster for Saturn only. https://www.bhphotovideo.com/c/product/44080-REG/Rosco_RS30411_304_Filter_Pale.html
     
  7. Ed D

    Ed D Well-Known Member

    Joined:
    Jan 12, 2017
    Posts:
    524
    Trophy Points:
    63
    Location:
    Sunny South Florida
    Bill, thank you for posting your filter findings. The Baader Contrast Booster appears to be a beneficial, all around filter for lunar and planetary observations. Many refractor users on other websites share this experience, especially those using achromats.

    In my previous post (#4) I mentioned stacking a Baader Neodymium filter with a light yellow filter. This combination was superb when observing planets with a longer 5" achromat I used to own. The Yellow filtered out the unfocused wavelengths, while the Neodymium worked its magic to enhance planetary contrast and detail. The resulting visual image was near APO-like.

    I opened three windows and pulled up, from the Agena website, the Baader Neodymium, Contrast Booster and Yellow filters. I found something quite interesting when comparing the trasmission bands. The Neodymium and Contrast Booster filters are similar with the exception that the Neodymium filter passes light below 480nm, whereas the Contrast Booster clips wavelengths below 480nm. The Yellow filter clips light at frequencies below 480nm. So, by stacking the Neodymium and Yellow filters I was getting results very similar to the Contrast Booster, especially the cut around 480nm. Check it out using the following links in three windows:

    Baader Neodymium: https://agenaastro.com/baader-1-25-moon-and-skyglow-filter.html
    Baader Yellow: https://agenaastro.com/baader-yellow-filter-2-fcfy-2-2458311.html
    Baader Contrast Booster: https://agenaastro.com/baader-1-25-contrast-booster-filter.html

    So, why not just buy the Contrast Booster? Because I have the Neodymium filters in both sizes and use them extensively when imaging the moon and planets. I also have a collection of colored filters for planetary study, which I sometimes stack to better isolate specific features.

    Again, thank you for posting your findings. Hopefully this will encourage others to experiment with filters for their planetary and lunar observations, especially larger achromat owners.

    Ed
     
    Last edited: Jul 10, 2020
  8. BillP

    BillP Well-Known Member

    Joined:
    Aug 3, 2015
    Posts:
    165
    Trophy Points:
    343
    Location:
    Vienna, VA
    Yup...experimenting is fun. And if you get one of those inexpensive ROSCO Swatchbooks which have about a hundred or more gel filters, can experiment for a lifetime! Just got my #8 filter a few days ago so will experiment with that too.
     

Share This Page