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bathroom buddy

Questions about my new 10" Dobby!

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Just wanted to say thanks to the people that gave me some advice last week regards buying my first ever scope - the upshot was that I am now the proud owner of a Skywatcher 250px flextube with AUTO controller!

I paid £510 off eBay and luckily the seller was only 20 minutes drive away so with that and a 2x Barlow lens and 6mm eyepiece on top I kinda think I've did alright?

First impressions were that it was a hell of a lot bigger in the flesh than I envisaged, but it kind of exudes a coolness about it that I'm still smiling about when I see it.

Haven't had a real good session with it yet apart from an hour after I bought it when the skys were clear so at the minute I'm just waiting for a good night to have it a spin. That hour though was quite something......

After getting it home amd and safely into the house I looked at and thought What the hell do I do now?!! Anyway, I manged to spot Jupiter and get that in my 25mm eyepiece and after a while of little movements here and there with the AUTO keypad I managed to centre her up and get it in to focus..........WOW!! I was like a little kid at Christmas time seeing Jupiter and the 4 moons come into focus, I honestly was speechless. I kept looking at the bright dot in the sky then into the eyepiece, then back to the sky not really believing what I was seeing.

After a while of experimenting with the different eyepieces I'm left with some questions......

1. I found it REALLY hard finding anything, including Jupiter with the smaller eyepieces especially the 6mm one. The slightest knock to the scope seemed to lose anything in the view, even focusing was difficult without the softest of touches. Is this the norm? I'm hoping it's just something that experience brings bein able to easily find objects and bein them to focus.

2. Following on from above, I found that all of my small movements to find Jupiter I was doing with the motorised mount - when I tried to move the scope juuuust a smidgen by hand it was so difficult to do it with any real precision. Is there a knack to moving a dobby small amount.

3. Finally, Jupiter was quite low on the horizon so my scope was not that far off horizontal. Again with the motorised mount I could do small precise movements to find and centre objects but manually it felt like the scope was kinda dropping with its own weight. So if I wanted to move the scope upwards slightly I found i had to manually nudge it past where I wanted it and let of fall back down a touch- does that make sense??!

4. What is the clutch tightener for (I think that is what is called - big screw in middle of mount) i tried tightening it right up to see if it got rid of the imprecision when the scope was getting towards horizontal but it didn't seem to do much.

I'm gonna do a full review once I get the chance to have a good session, so in the meantime thanks again in advance!

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Congratulations on your new scope :)

For easier finding, I'd recommend (AND loads of folk on SGL!!!) a Telrad finder, this projects a series of circles on the sky in the area you are looking at and combined with a decent sky chart makes finding objects so much easier.

Start off with a low power eyepiece, centre the object then use a higher power eyepiece to get a better view of what you want to see.

L.

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got the baby brother of yours [the 200 flex goto] nice scope and the telrad will help as lorne pointed out. the 10" seems to be the butter size for portable dob's. the nut stops the clutch slipping [if your scope is horizontal but its slips /when raising to vertical ] then you need to tighten it but be careful as the more tight then the more the motor has to overcome the drag causing strain on the electrics i literally turned the nut an eight of a turn and it now is slip free [even with a telrad . also you can put a small weight on the base which will also help in the vertical lift

Edited by dtr42

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+1 for the Telrad. Very handy bit of kit.

Not used the 10" Flextube auto but a Dob should move very smoothly and easily by hand.

I have tried the 16" version manually and TBH found that okay, a bit tougher to move than a fully manual scope but certainly not hard to use.

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Nice scope, but it needs a Telrad, good wide EP (high mm) then just as much practice as the clouds will allow, hope your using Stellarium.....:)

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1) You find with the large eyepieces, they give the biggest field of view, then swap to the smaller ones for greater magnification and detail if possible.

One of the problems with any scope it that any touch can move them and on a Dobsonian that is the principal method of moving them, so expect it to move.

2) Really it is just experience and as you have the motor drive you may take some time to get used to manually positioning the scope simply because you will use the motors.

3) A dobsonian mount cannot be balanced for all positions and when horizontal is probably the worst so it will "move" the most, either down or up. I guess the motors will be engaged and so prevent more as you or the scope will have the normal friction and that added by the motors. The travel past and let it drop is the backlash in the system, you may be able to adjust this and minimise it but it means poking into the drive train.

4) Sounds like a friction adjuster for the base and the lateral movement, should be similar for the up/down. Don't over tighten either.

The next month or three will simply be learning and getting used to the thing, the setup and operation of it. Just remember that kicking it and throwing the eyepieces as far as possible is just a short term reduction of annoyance.

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when you use the arrows to track/centre the object you should drop the scope below the target then use the "drive" to move up to the object same as when slewing left to right you stay slightly left then use the right "drive" to get to target as the older flex dobs had a slack drive and so you need to make sure the drive is holding the scope at the position your looking at [this allows the scope to track for a decent 20-30 minutes without losing your object in the FOV

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To be fair to FLO they do tell you before you order that items are not in stock but that they will notify you when they are, I had this issue with a webcam adapter and at least they give you the opportunity to find one elsewhere (not easy with a telrad but this does show how popular and useful they are)

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Red dot finder is just as good as a Telrad, if you can't get one. They seem to be rarer than hen's teeth nowadays. Must be all the recommendations.

Nick.

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+1 for the Telrad too!

Also agree to start with a low power eyepiece (25mm) to start then switch gradually through your eyepieces to higher power keeping the object in view the whole time!

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I use a RDF and a Telrad with my 10 inch Dob and it really does make life much easier, I would get your hands on one ASAP :)

Sent from my iPhone using Tapatalk

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