453 replies to this topic

[BillP]

With the Mars 2020 Opposition just 4 months away, I have been thinking more about filters to enhance martian observing.  In the past I have found the #30 Magenta and the Baader Contrast Booster filters most effective on Mars, both singly and stacked.  However, in my reading I find some have liked other filters and there is also a new filter I've recently come across that may be promising.  I will soon have in my possession a number of these filters and plan to give them a go on Mars, Jupiter, and Saturn as these planets are currently in the early morning sky.  So home to get some good comparisons over the next 30 days or so and will report findings.

 

Telescopes: TSA-102 f/8 SApo, and APM/Lunt-152 f/7.9 ED-Apo

 

Classic Design Eyepieces: 10 Ultramono, 8 Carton Plossl, 7.5 Tak LE, 7 Vintage Celestron Volcano Ortho, 6 Starbase Ortho, 6ZAO-II, 5 XO, 5 Tak LE, 4 Vintage Meade Ortho

 

Wider Field Eyepieces: 10 XW, 9 Morpheus, 8 BST Starguider, 7 XW, 6.5 Morpheus, 5 XW, 4.5 Morpheus

 

Filters:

• Baader Moon & Skyglow
• Baader Semi-Apo
• Baader Contrast Booster
• WO VR-1
• VERNONscope #30 Magenta
• Omega Optical Color Enhancing Filter*

* - A patented design that covers any interference coating which blocks passbands centered substantially at 490nm and 590nm and transmits light at the wavelengths of the three prime color bands centered at approximately 450nm, 530nm, and 650nm.

 

For any given night will determine which eyepiece without filter is providing the overall most pleasing and detailed planetary view, and then will run the filters through that eyepiece.

 

Now I just need the rain to stop please!!!!

 

PS - This thread has been tagged with a new tag called "Filters".  Anyone starting a new thread that address filters please add this tag to your thread so will will be easy to find all discussions related to filter use!  Thankyou CN ADMINS for adding this tag to the tag list

Edited by BillP, 18 June 2020 - 01:41 PM.

[sunnyday]

I can't wait to read this.

[Daniel Mounsey]

contrast booster all the way.  

[BillP]

Update #1 ....

 

Used TSA-102 yesterday morning and observed Jupiter and Saturn for 3 hours.  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 - may seem low but I typically use 135x for planetary and have become skilled at discerning small details at lower magnifications).  Filters were rapidly compared against each other by placing them on the eye lens (why I chose a 20mm ER eyepiece).  Tonight observed the Moon to test the filters.

 

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.

Edited by BillP, 27 June 2020 - 02:29 PM.

[RLK1]

FYI: The Celestron Mars filter, discontinued but apparently available on backorder via Adorama, continues to impress on the polar cap on Mars. The latter is quite prominent now without a filter but with it I could see the swirl appearance of the cap, cleanly and clearly with a 9mm BGO in my 16" f4.5 dob. The filter doesn't do much for darker markings on the surface but if you like polar caps, you've found your filter. 

In an off-use application, I tried it on galaxies since the Orion Mars filter has similar transmission characteristics with the DGM GCE filter.  The views of various galaxies like M51 were better without the filter under dark sky conditions but still doable with it.  However, I need to try it under my moderately light polluted conditions at home to see if it helps or not.

I didn't have a chance to use my baader contrast filter on Mars yet but likely will in July. I read somewhere that dust storms on Mars begin their season somewhere in July and can progress for a couple of months. Hopefully we won't have a repeat of the last opposition...

[Rock22]

After reading the more recent suggestions about Mars filters, I picked up 2” versions of the Baader Contrast Booster and the Vernonscope magenta #30. I thought about the Celestron and Orion Mars filters, but I didn’t see 2” versions of those.

Tried to pick up an inexpensive 2” moon and skyglow. I remember reading on CN that the moon and skyglow can be stacked with another filter to give good views of Mars details, but I can’t remember which filter to stack it with and in which order. I can’t find that thread in my searches.

In any case, your shootout is very helpful. Waiting to see how the filters work for you on Mars during your comparisons once the planet clears your tree line. Thanks for providing your report here!

[Daniel Mounsey]

I had forgotten to mention how nice the contrast booster is on Mars.

[sanbai]

I'm looking forward to seeing the comparison between the three Baader filters. All them have a neodymium base, with the M&SG being the base filter. The Apo, which I have, cuts the extreme violet; the contrast booster cuts a bit more.

I've noticed that the Apo reduces light (good for planets) and makes the GRS pop. Many times I forgit it was there I'll let the experts say more about it .

[jap201]

think i'm going to give that Baader Contrast Booster a try.  was watching jupiter and saturn last night without any filters. i'd like a little more contrast to see the NEB and SEB clearer.  thanks for this shootout, going to keep watching it.

[Jon Isaacs]

Bill:

 

I'm not sure how you do these shootouts.

 

I've tried several but every time I find a hole in the lens..

 

I must be doing something wrong.

 

 

Jon

[BillP]

Bill:

 

I'm not sure how you do these shootouts.

 

I've tried several but every time I find a hole in the lens..

 

I must be doing something wrong.

 

 

Jon

Took me a while to get this...but finally sunk in

 

Also better to do the shootout before you mount the filter on the eyepiece...less expensive that way

Edited by BillP, 28 June 2020 - 06:57 PM.

[MarMax]

Something tells me there will be a boost in sales of the Baader Contrast Booster, me included in that group   

 

Been on the fence and now Bill has bumped me off. Great reviews and looking forward to more updates!

[MrJones]

JUPITER

 

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

Thanks for doing this. I'd be interested to get the Orion or Celestron Mars filter in here! They are dielectric broadband filters like the Orion Skyglow but have less blue and more red (starts at 600nm) so the tint is more natural.

[mike bacanin]

Something tells me there will be a boost in sales of the Baader Contrast Booster, me included in that group   

 

Been on the fence and now Bill has bumped me off. Great reviews and looking forward to more updates!

Mine arrived today!

 

Mike

[BillP]

You guys need to wait til my Semi-Apo and Moon&Skyglow come in as hear they may be excellent on planets as well.

[desertlens]

Bill, Which diagonals are you using?

[BillP]

Zeiss Prism.

[Rock22]

At f/15, my main planetary scope (180mm mak) will offer dimmer views than the ones you get in the apo refractors you're using.  Planets should be bright enough for this mak and filters, right?

 

I'm also going to use the filters and compare views of Mars using a 127mm f/6.5 achro, a 102mm f/9.8 achro, and an 80mm f/7 triplet.  I might try a 2x Barlow, a 3x focal extender, and a 5x Powermate on the triplet, probably with a 20mm 100-deg eyepiece.

 

I'm looking forward to trying the contrast booster on Jupiter, Saturn, and the Moon as well.  I found a 2" moon & skyglow filter, and will see how that works, too.

[BillP]

At f/15, my main planetary scope (180mm mak) will offer dimmer views than the ones you get in the apo refractors you're using.  Planets should be bright enough for this mak and filters, right?

Not right.  How bright a planet appears at a given magnification will depend on the aperture.  So if you are viewing Mars at 250x, then your 180mm scope would show it 40% brighter than a 152mm scope if all we were considering was the aperture.  All your f/15 is doing is governing what eyepiece focal length you need to achieve 250x.  However, you do get light loss from the CO and the two bounces on the mirrors and from the 2 air-glass interfaces of the meniscus vs. an all refractive Apo which is just getting light loss from the 6 air-glass interfaces.  But if your Mak has a system transmission similar to Celestron SCTs with Starbright coatings, which they say averages 83.5% over the entire spectrum, then after adding in the CO your Mak will still be around 13% brighter than a 152 triplet Apo, both viewing a planet at the same magnification.  So basially, your 180 Mak is gathering light at about the level of a 162mm Apo, but has the resolving power of a 180mm Apo since aperture is aperture when it comes to resolution.

 

I used a 4" for the first round and planets were plenty bright for the majority of the filters.  And your Mak is gathering 2.5x more light than my 4" Apo!!!

Edited by BillP, 29 June 2020 - 06:29 PM.

[Rock22]

Not right.  How bright a planet appears at a given magnification will depend on the aperture.  So if you are viewing Mars at 250x, then your 180mm scope would show it 40% brighter than a 152mm scope if all we were considering was the aperture.  All your f/15 is doing is governing what eyepiece focal length you need to achieve 250x.  However, you do get light loss from the CO and the two bounces on the mirrors and from the 2 air-glass interfaces of the meniscus vs. an all refractive Apo which is just getting light loss from the 6 air-glass interfaces.  But if your Mak has a system transmission similar to Celestron SCTs with Starbright coatings, which they say averages 83.5% over the entire spectrum, then after adding in the CO your Mak will still be around 13% brighter than a 152 triplet Apo, both viewing a planet at the same magnification.  So basially, your 180 Mak is gathering light at about the level of a 162mm Apo, but has the resolving power of a 180mm Apo since aperture is aperture when it comes to resolution.

 

I used a 4" for the first round and planets were plenty bright for the majority of the filters.  And your Mak is gathering 2.5x more light than my 4" Apo!!!

I don't know what the light transmission is on these Synta 180mm maks, but I highly enjoy the scope and the planetary views with it so far.  I saw Uranus and Neptune distinguishable as blue-green discs, and Jupiter and Saturn in opposition were excellent in the mak.

 

The only planet I have yet to have a satisfying view of is Mars.  2018 was disappointing because of the dust storm.  Being so bright and small added to the difficulty of seeing anything other than a tiny, orang-y, glowing, fuzzy ball.  I'm really looking forward to using the filters soon to tease out details around the opposition.

 

Waiting on your results for Mars!

[Sol Robbins]

Bill,

 

If I recall correctly, the semi apo filter is just a neodymium substrate with a minus violet coating. I was at a NEAF where Markus Ludes showed me and Al Misiuk what was the new Baader Moon & Skyglow stacked with a Sirius Optics MV-1 minus violet filter while demonstrating a 6" achro.

 

Al then offered the MV-1 coating on a neodymium substrate and called it the MV-2. The Semi Apo, neodymium substrate plus minus violet coating, came later. I don't believe that the Semi Apo will be seem clearly better or change what you have already observed in this shootout as beneficial. 

 

Saturn doesn't really show the kind of benefit from filters the way filters do on the other planets. I find filters on Saturn usually benefit a singular kind of feature while diminishing most the others.

 

I'll be curious to read what you think as your comparison evolves.

Edited by Sol Robbins, 29 June 2020 - 09:14 PM.

[BillP]

Thanks for doing this. I'd be interested to get the Orion or Celestron Mars filter in here! They are dielectric broadband filters like the Orion Skyglow but have less blue and more red (starts at 600nm) so the tint is more natural.

Remember. that was the Orion Skyglow filter.  The spectrum of the Baader Moon & Skyglow is much different.  Hopefully that one will be more usable than the Orion. 

 

Does anyone have the spectrum chart for the Celestron Mars filter?

[sanbai]

Bill,

If I recall correctly, the semi apo filter is just a neodymium substrate with a minus violet coating.

That's right. The Contrast booster is a step further in that direction. Actually those filters are also UV/IR blockers, but that's irrelevant for night visual use.
Baader's website has all this information.

The Semi-Apo and Contrast booster will also help to increase contrast due to elimination of residual chromatic aberration (be removing the violet-bluish part, nothing fancy). This is in addition to what the neodymium filter does.

Edited by sanbai, 29 June 2020 - 09:58 PM.

[RLK1]

Remember. that was the Orion Skyglow filter.  The spectrum of the Baader Moon & Skyglow is much different.  Hopefully that one will be more usable than the Orion. 

 

Does anyone have the spectrum chart for the Celestron Mars filter?

I've been searching for it as well. Thus far, nothing...

[RLK1]

The Celestron Mars filter info from the last opposition:

"By combining the best properties of red and blue planetary filters, users will be able to view the polar ice caps and meridian details"...

https://www.bhphotov...ing_filter.html

Entertaining video in the above link describes a few of the properties of the filter.