jetsfan122
member
Reged: 07/17/09
Posts: 60
Loc: Long Island,New York
|
|
I'm thinking of installing Bob's Knobs on my CPC 800 and was wondering if anyone knew if by installing them , would they interfere with the lens cap and/or a solar filter ?
--------------------
_____________________________
Vinny
_____________________________
Celestron CPC 800
Orion EON 80mm ED APO
Celestron eyepiece kit ( ugh )
Baader Hyperions 8mm,13mm,21mm
Televue Nagler 11mm
Explore Scientific 82 degree ( 18mm )
Agena Astro 38mm
|
dtsmith
professor emeritus
Reged: 03/22/06
Posts: 708
Loc: Lafayette, IN
|
|
They do not interfere with the lens cap. I suspect that they won't interfere with the filter, but I don't know that for sure. The only thing that doesn't "work" once they're installed is the little pop off cap that normally covers the collimation screws.
--------------------
Dan
NP-101 / DM6 / Sky Commander
CPC 800 XLT / WO SCT Focuser
Stellarvue 9x50 RACI Finder
W.O. 66SD
|
Digital Don
Pooh-Bah
Reged: 01/20/04
Posts: 1284
Loc: Manteno
|
|
You might want to give that some additional thought. Here's what Celestron says about 'aftermarket' parts: Celestron Support Site
Pay special attention to the last line of the article starting with the word NOTE:
Don
|
Bob Griffiths
Postmaster
Reged: 10/10/05
Posts: 6556
Loc: Frederick Maryland
|
|
Yep I read that...
BUT still ordered a set of Bobs Knobs just as I have done with all of my other SCTS...
I'm sorry but if I had a warranty issue you can bet the farm the Bobs knobs would be removed and the original factory screws put back in place BEFORE I shipped it back to Celestton...
My major reason for doing so is to make sure I still had them to reinstall after I received the scope...I would not want Celestron to replace them
Bob G
--------------------
CPC1100
Nexstar 8i + GPS & Rays Brackets
Denk S1 power switch
Orion 100 mm Refractor
Meade LXD 55 ...AR-5 127 mm Refractor
Exploradome Observatory S.I.E. (Smiling Irish Eyes)
Gerbring Heated Motorcycle clothing in the winter
39*21'03" N
77*28'12" W
The sky over my head....
|
b1gred
Enginerd
Reged: 04/01/04
Posts: 15711
Loc: Castle Rock, CO 6677' MSL
|
|
At the recommendation of the shop where I purchased my scope (or more properly with the understanding they would recollimate my scope as long as I own it AS LONG AS I don't put 'aftermarket collimation screws' on it) I have left my 925 "factory original". After more than 5 years of use (most of that use involving transport by road), my scope is still perfectly collimated.
I've used my artificial star to check my collimation (and collimate others' scopes) and I've done star-checks on mine, it's still 'dead on', so I'd say, instead of investing in Bob's Knobs, do a good/solid collimation, and leave it alone.
--------------------
"Dark Skies & Great Viewing"
RandyR / W0RDR
GPS 9.25 XLT/Sky Align /FeatherTouch
TV85 w/FeatherTouch
|
Digital Don
Pooh-Bah
Reged: 01/20/04
Posts: 1284
Loc: Manteno
|
|
Don't get me wrong, I'm personally not against using aftermarket collimation screws.
However, over the last 35 years or so I've owned a dozen Schmidt-Cassegrain telescopes ranging in size from 5" to 11" and have never seen the need for anything other than what Celestron supplies.
My experience has been that once the scope is collimated, it stays in alignment with 'normal' transportation and use.
Don
|
Bob Griffiths
Postmaster
Reged: 10/10/05
Posts: 6556
Loc: Frederick Maryland
|
|
Heck I stored my 8i in the trunk of my car for close to 2 years and 100,000 miles...before I retired.... Not your normal causal travel to a star party...
Collimation held pretty darn well...only requiring a tweak every now and then Only exception was when I had to travel around and thru the coal region of Pennsylvania (worst darn roads in the country) .. Never made it out of that area without collimating the scope..PERIOD !
Bobs Knobs were a god send to me at the time and I continue to use them even now when I'm retired and do not store my scopes in the trunk of a car 24/7...
Bob G.
--------------------
CPC1100
Nexstar 8i + GPS & Rays Brackets
Denk S1 power switch
Orion 100 mm Refractor
Meade LXD 55 ...AR-5 127 mm Refractor
Exploradome Observatory S.I.E. (Smiling Irish Eyes)
Gerbring Heated Motorcycle clothing in the winter
39*21'03" N
77*28'12" W
The sky over my head....
|
mclewis1
Thread Killer
Reged: 02/25/06
Posts: 3938
Loc: New Brunswick, Canada
|
|
When the manufacturer says "may void the warranty", it really means "we'd like it to void your warranty but our lawyers won't let us say that if you don't damage the scope, so we'll use wording to scare you into doing things our way".
Correctly installing Bob's Knobs isn't going to be a problem to Celestron, but mess up the installation and possibly damage (cross thread a bolt, drop one onto the primary, etc.) the scope and you'll be on your own.
--------------------
Mark
C11, C6, APM/TMB115, and AT80ED - Tandem mount CGE and CG-5A, WO EZ-Touch and AT Voyager
25x100s and 8x56s, T-Mount Light, Mark 1 eyeballs - Modded 350D, DSI-P, SPC900, Mallincam
Just because you can doesn't necessarily mean that you should
|
dtsmith
professor emeritus
Reged: 03/22/06
Posts: 708
Loc: Lafayette, IN
|
|
My scope went back to Celestron for a warranty repair (bad motor control board and the infamous grease on the corrector issue) with Bob's Knobs installed. I was told by the phone tech prior to shipping it back that I didn't need to remove them. There were no issues having Bob's Knobs installed and it came back with the screws still in place. I'm with Mark, as long as the warranty issue doesn't have anything to do with the collimation screws, there shouldn't be a problem. As far as if Bob's Knobs are worth it, that's clearly personal preference.
--------------------
Dan
NP-101 / DM6 / Sky Commander
CPC 800 XLT / WO SCT Focuser
Stellarvue 9x50 RACI Finder
W.O. 66SD
|
KerryR
Pooh-Bah
Reged: 12/05/07
Posts: 1141
Loc: SW Michigan
|
|
My LX90 doesn't hold collimation very well, so Bob's Knobs really help on that scope.
I was going to order a set for my CPC11, but found that it holds collimation so well that I don't feel compelled to put them on that scope.
It IS nice to have them installed, though, in the event you get to your dark spot, need to collimate, and find you don't have a screwdriver...
--------------------
Kerry
|
Digital Don
Pooh-Bah
Reged: 01/20/04
Posts: 1284
Loc: Manteno
|
|
"When the manufacturer says "may void the warranty", it really means "we'd like it to void your warranty but our lawyers won't let us say that if you don't damage the scope, so we'll use wording to scare you into doing things our way."
I'll have to respectfully disagree with that interpretation. Warranty coverage is ultimately at the discretion of the entity issuing the warranty. If a purchaser does not agree with the terms of the warranty, they have the option of not buying the product. I'd be more inclined to think that 'MAY' indicates that they have the option to allow or deny warranty coverage if you've changed the product.
Technically, adding a different finder, visual back, or eyepiece could be considered a 'modification'. I suspect they're covering their position depending on the nature of any modifications that have been made and what effect such modifications have had on the warranty issue.
On the other hand, if one looks at the 'Warranty Tab' here: Celestron CPC it says that the warranty IS void if the product is modified.
Don
|
Paul McC
scholastic sledgehammer
Reged: 02/03/06
Posts: 983
Loc: Southern NJ
|
|
My Bob's Knobs have been terrific- I think it's absurd that neither Celestron or that other company have these (or something similar) as standard collimation screws. Putting a screwdriver near glass is a bad idea... especially in the dark.
That said, the installation is very tricky on the CPC OTA. Read the instructions very carefully on installation. Care must be taken to thread one at a time and to AVOID over tightening of the other two screws/knobs. Doing so can result in the secondary rocking back away too far for the new knob going in to reach and thread. I know this since it happened to me.
Should this happen to you, orient the scope so that gravity pulls the secondary down where needed, and loosen the other two screws/knobs slightly until you can get the one that got away threaded. This worked for me.
Once the BKs are installed, your collimation will hold well, and will be easy to adjust anytime it's needed.
Cheers,
Paul
--------------------
My Current Time Machine is a
Celestron CPC 1100 GPS XLT
aka - The Time Tunnel
My Celestron CPC 1100 Webpage:
http://mywebpages.comcast.net/pmccullough/skyportcpc1100.htm
Latin phrase to live by: "Illegitimis nil carborundum"
|
Norm 1701
member
Reged: 08/19/08
Posts: 62
Loc: Pittsburgh PA
|
|
Randy, I was shocked to hear you say your collimation held permanently. I have to adjust mine almost every time I take it to a dark sky, and when it has been shipped. Of course I do live in PA, and the roads can be poor. None the less, I was very surprised. Loctite?
--------------------
Norm
CPC 1100
Zenithstar 80
C8 on Voyager Mount
|
astrovienna
super member
Reged: 12/04/06
Posts: 131
Loc: Vienna, VA
|
|
Thanks for the tips, Paul. I would recommend that anyone installing Bob's Knobs (I reinstalled them on a CPC11 today) not rely solely on the paper instructions provided with the knobs. On the website are good instructions specific for your scope type and manufacturer, and a FAQ sheet as well. Read these before you install and it will be much easier.
Kevin
--------------------
The Hole in the Trees Skybox
CPC1100 on a Milburn wedge
C8 Phoenix (1985 Super C8+ remounted on a Nexstar GPS fork)
Meade DSI II Pro
DMK 21AU04.AS
|
b1gred
Enginerd
Reged: 04/01/04
Posts: 15711
Loc: Castle Rock, CO 6677' MSL
|
|
There's nothing like the washboard roads and rut-trails I've had my scope on. 5 years and still solid...
--------------------
"Dark Skies & Great Viewing"
RandyR / W0RDR
GPS 9.25 XLT/Sky Align /FeatherTouch
TV85 w/FeatherTouch
|
Previous
Index
Next
Threaded
Edit
Reply
Quote
[Re: 