Click here if you are having trouble logging into the forums
Privacy Policy |
Please read our Terms
of Service | Signup and
Troubleshooting FAQ | Problems? PM a Red or a Green Gu.... uh, User
CESDewar
GorillAstronomer
Reged: 01/16/05
Posts: 1802
Loc: Morganton, GA, USA
|
|
Someone had posted in another forum that they had been told the TMB92SS did not work with binoviewers, but this is very definitely not true as all three pairs of binoviewers I tested (Burgess-C, BV3, DenkII's) were fine.
I used the BV3's with the 1.95x OCA and Pentax XF8.5mm EP's to watch the entire transit of Ganymede across Jupiter last night. This represents a magnification of about 116x. Seeing was below average with substantial turbulence. I also switched back frequently to view in cyclops mode with a 5mT6 (101x), 2.5mT6 Nagler (202x) and the 2-4mm Nagler zoom, spanning 126-252x.
I watched the full transit of Ganymede and was surprised that it was clearly seen at all times as a nice tight spot as it crossed Jupiter on the NTB. The GRS was trailing just a bit behind Ganymede - thereby presenting a good view.
The difference in binoviewing was really pronounced that night. While I could see the disk of Ganymede in cyclops mode, at no point was I able to convincingly catch the GRS, while it was relatively easy in the binoviewers. This was an excellent example of how binoviewing contributes to contrast as well as acuity. I was also impressed with the difference between the pale gray of the thicker SEB and the very obvious tint of orange/brown coloring of the NEB. The NTB and NNTB were also clearly visible in the binoviewer when the seeing steadied. I find Binoviewers just wonderful for eeking out the last tiny piece of viewing resolution in smaller scopes.
Although the BV3's are outgunned by my Denk II's, they still get plenty of use because the are lightweight and perform remarkably well for their cost - I also have a lot of 1.25" filters which is another reason I hold onto them.
--------------------
|
Joe Ogiba
Post Laureate
Reged: 02/14/02
Posts: 3326
Loc: NJ USA
|
|
Quote:
Someone had posted in another forum that they had been told the TMB92SS did not work with binoviewers
With a barlow or optical corrector any scope should work with a binoviewer. I just wish there were more short tube refractors that would work without the need for barlows or OC's like the SV115T20.
--------------------
Pentax PF-80ED
Meade 102ED APO
Orion EON 72
120ST
Apex 127
C6 XLT
CR150
C9.25
XT10
Zeiss 7x42 FL
Canon 10x42L IS WP
15x50 IS
12x36 IS II
Garrett Optical 28x110 HD-WP Signature Series
Oberwerk BT-80 45
Apogee RA-88-SA
Denk II Power x Switch binoviewer w/13mm Ethos, 20mm Pentax XW's, 20mm Widescan III's.
|
CESDewar
GorillAstronomer
Reged: 01/16/05
Posts: 1802
Loc: Morganton, GA, USA
|
|
Ok, I spent a lot more time this evening with binoviewers, and I do have to say the TMB92SS is not nearly as friendly with the Denk II's as the TMB105/650 is. I was unable to find any combination of extension tubes or OCA's that would allow the power switch to work at all settings.
Even in the TMB105/650, it was a struggle to get all three settings working - the problem is that the Denk II's have an incredibly wide range of focus settings that unless you can rack in and out some 5+" you are not going to find one solution. Yes, sure I can take the TMB92SS apart and remove the extension tube between the main tube and focusser, but this is unrealistic - the point of the PowerSwitch was to shift the slide to achieve different magnifications, not spend five mintues disassembling the scope  and it basically renders the DenkII power switch pretty useless. I have both the low and high power OCA's from Denk as well as two different sets of extension tubes - but no luck. It's not a big deal as I can use the Denk II's on the Barlow setting and have several sets of EP's to use with it, but it was a bit disappointing to find out that it works so much more poorly than my TMB105/650.
Anyway, if someone else has this combination and found something that works with all three settings on the power switch, do let me know!
I'm also curious to know if the unit from Earthwin also has such a wide variation in focus settins in its three-way power switch.
--------------------
|
JimP
sage
Reged: 04/22/03
Posts: 345
Loc: South Carolina
|
|
I must say I heartily agree with your assesment of cyclops vs binoviewing on the planets (The Moon as well). I can truly see more detail. Having said that I am often lazy andd will observe quickly wih a single eyepiece. Posts like yours keep reminding me that I need to take the time to put in the binoviewer!
JimP
|
dmgriff
sage
Reged: 09/20/06
Posts: 257
Loc: 30 degrees latitude, USA
|
|
Quote:
excellent example of how binoviewing contributes to contrast as well as acuity.
Quote:
I heartily agree with your assesment of cyclops vs binoviewing on the planets (The Moon as well). I can truly see more detail.
I agree wholeheartedly, and this bud's for all. (Rain, rain, and more rain, but the temp is nice).
Good viewing,
Dave
|
NoiseJammer
member
Reged: 09/16/07
Posts: 40
Loc: Toronto, ON
|
|
I did a quick test that should allow you to determine whether your scope is capable of working with the PxS. My set up was FLT110 (TMB) / R2 diagonal / Denk II / Nagler 16's.
At minimum magnification, the system achieved focus at 29 mm while at maximum magnification it was focused at 84 mm. This suggests that you must have 55 mm focus travel. If you have less that 55 mm focuser travel, you can't work through the entire magnification range.
If memory serves, the FLT + Part S + Maxbright diagonal + dual PxS behaved very similarly, although it hasn't been on my scope in more than 6 months.
hth
Bruce, Toronto
--------------------
LX200/12 & Borg 60ED f/3.8
TOA-150F / Denk II on DM6
... and way, way too much light polution.
|
wrather1
AstroBear
Reged: 10/25/05
Posts: 2913
Loc: Dallas, Texas
|
|
I cannot get my Denks to work with my TMB130SS. No way, no how.
But the bino works FANTASTIC on my RCX.
DW
--------------------
"Don't worry about what telescope you own, or its quality. Just get out under the night sky, and enjoy God's wondrous universe." - T. M. Back
Meade RCX400-12 on JMI trolley "Ursa Major"
TMB 130SS on EQ6 PRO "Ursus Polaris"
Orion ED80 "Ursa Minor", WO ZS66ED "grab-'n'-go"
Canon EOS 30D (Hutech), Meade DSI, Philips ToUcam Pro
North Texas Clear Sky Chart
|
Rick
Carpal Tunnel
Reged: 04/12/05
Posts: 2559
Loc: Tokyo, Japan
|
|
My Baader Mark V works fine without the OCS with plenty of focus travel on my 130SS. Mine has the FT focuser though without any extensions.
cheers,
Rick
--------------------
www.japanastro.com
|
|
1 registered and 1 anonymous users are browsing this forum.
Moderator: EdZ, jrcrilly
Print Thread
|
Forum Permissions
You cannot start new topics
You cannot reply to topics
HTML is disabled
UBBCode is enabled
|
Thread views: 534
|
|
|
|
|
|
|
Previous
Index
Next
Threaded
Edit
Reply
Quote
