M27 Dumbell at 2.8m f/l

[Steve Ward]

What's happened to the scope Richard ? Sounds expensive......

[squeaky]

I was out imaging and got caught in a snap shower. The heavens really opened - it was like being in a car wash. I slapped the laptop shut and put it under my picnic table, legged it all of seven yards to my car and grabbed my cover and got it over the scope.

After I'd dried myself out and the rain was over I uncovered it and found that all the water from on and in my OTA had drained down onto the cover of the AZ motor encoder assembly, so I mopped it all dry and recovered for the night. Next day I lifted the cover off, wiped away condensation and left it out all day to dry in the sun and breeze.

That night got a "No connection to mount" error. Unplugging and replugging the connector to the AZ assy. cleared it for a while but it kept coming back, so I took the scope indoors. Noticed that there are two small holes in the TOP of the cover, so lifted it off and found water sitting on the encoder and its circuit board, and on the main circuit board by the connector. Carefully dried it all off and left it open in the kitchen all day to air out thoroughly.

Next night got a connection, started star align - but when it started slewing to the second star the AZ just kept driving round in circles. More like the Magic Roundabout than a scope. The handset display showed a constant 000deg with the mins varying from around 20 to around mid 30's only. Back indoors I lifted the the encoder and, as I lifted it - water dripped out of it! So opened up the encoder and very carefully dried it all up and, once again left it all open all night to air out.

Next day did a simulated align but still got the Magic Roundabout, so contacted the shop. They sourced from OVL and the guy who does the techy stuff was on holiday until yesterday <sigh> no answer back as yet.

It's under guarantee and the shop say I have invalidated it by opening up to dry things. I'm maintaining I wouldn't HAVE to have opened it up if the cover over electronics on a piece of kit meant to be used out of doors didn't have holes in it!

[Steve Ward]

Ouch !

I hope they see sense and sort it for you ,

If kit's designed for outdoor use it should be capable of withstanding a quick shower without dying .

At least have drain holes at the bottom of the boxes.......

Steve.

[squeaky]

The two holes in the top of that cover are a fault of "conservative engineering".

The cover for the Alt assembly and the AZ assembly are exactly the same moulding. The ALT one has two small holes in it so that you can screw on the bracket for the synscan hand controller. So the ones in the bottom AZ don't actually need to be there at all - and they don't bother to seal them with anything.

Also there are no gaskets of seals under the covers (between the cover and the side wall or base) so any heavy dew fall can creep under them.

Not to mention that I had a lot of tracking problems because the mount was getting ever more difficult to move. So bad that the AZ worm screw was jumping on the worm gear. This was because the mount is covered chip board. EXCEPT... it's not covered everywhere! All the cut edges that are out of sight have not been covered. or treated. So again, rain water, or even heavy dew fall can creep in and the chip board blows out and warps. I've dealt with most of it, but there's no readily available info on how to set the clutch frictions to their optimums, so it's all trial and error.

I'm going to have to save up for an EQ6. I sure as heck won't be buying a dob again.

[Tim]

Nice start on this piccy

Forgive me for not having time to read all the previous posts, so if my reply is a duplicate just ignore. To get decent guiding results with a long focal length scope you will be best off with an off axis guider.

Also, make sure your polar alignment is as close as possible to perfection.

I image with my C11 @ f10 over 20 or 30 minutes with no trailing so it can be done, you'll get there in the end.

Cheers

Tim

[x6gas]

Nice start on this piccy

Forgive me for not having time to read all the previous posts, so if my reply is a duplicate just ignore. To get decent guiding results with a long focal length scope you will be best off with an off axis guider.

Also, make sure your polar alignment is as close as possible to perfection.

I image with my C11 @ f10 over 20 or 30 minutes with no trailing so it can be done, you'll get there in the end.

Cheers

Tim

Thanks for the encouragement Tim - good to know it can be done.

Yes, I am using an OAG with my set up; that bit seems fine. I must confess that I have only been doing a polar align using a polar scope and not drift aligning. I don't have a permanent set-up, but I do mean to use the polar align function on the mount which, as I understand it, shows you where a star should be with perfect PA so that you can move the mount to align on it.

I was struggling to get good settings with PhD - my mount was fairly poorly adjusted so I have set-up the worm gear mesh to be a bit better and if I can't get any better then I'll have the mount apart for a DIY hypertune...

Could I ask what software you use to guide with? As I say, I use PhD but also have AstroArt which I understand Olly Penrice uses... Any tips on settings at this F/L also gratefully received!

Cheers, Ian

[Ewan]

Hi Sqeaky, I was joking but if you could have a bash at getting more data out of it just so I can really see what my canon is collecting , I have DSS'd it 152 subs from 253 & I think I have some half decent core / dust lane detail but I can't seem to get any colour (don't think I had camera on mono :-)), the tif is 152mb & the jpeg is fairly big, what size could you work with roughly email wise ?, if it's jpeg I realize it's not as good but it would give me an idea.

Just doing an amaturish mosaic by moving the goto around M31 so the core is in near the corner of frame then use 'mosaic' stacking option so (fingers crossed) it does overlay them all, I should get a small frame but a bigger more detailed final shot ?

It's not ideal, granted but I like trying my abilities

[squeaky]

Blimey that IS big.

Can't cope with that by email, maybe the jpg. Could you upload it somewhere like erm... astrobucket is it?

The limiting factor is more likely to be your own upload / attachment limit on your email software rather than my downloading limit. I'll PM you my email address.

Erm... as for lack of colour.... reload your autosaved tiff into DSS and click on the saturation tab. Move the slider right (probably a LOT from my experience so far) and apply it. Then save to file. You'll probably still need to give saturation more lifting in post processing.