Gina's Esprit 80ED Pro Unboxing and First Impressions

[ollypenrice]

Thank you Olly   You raise some interesting points   With the proposed 4 scope setup there will always be one free that I could put the guide camera on.  And I still have the ST80 I could bung on somewhere if I find I can use all 4 scopes for imaging   Also, many DSOs can be imaged without extended exposures and may prove OK without guiding with the EQ8.  Or I can have the OAG on the MN190 and guide that way, as I have in the past.  What I really need now are some clear nights

I shall be getting a mini lathe and plan to make my own adapters etc.  I also have uses besides astro for a lathe.

Heresy!!  

Moderators, Inquisitors, quick! This must be nipped in the bud.

 lly

[Gina]

:D

Well I only use 5 and 10m subs with the Heart mosaic I was doing but most of the DSOs I like to have a go at DO want rather longer though I've only gone up to one hour so far.  May tackle fainter objects now I have the EQ8.  But I will be interested in seeing how long exposures I can use without guiding

[Tinker1947]

If your making your own adapter, go the the extra mile and make it variable in length, say 2/3rds of your required length for a female section and 2/3rds for a male section both bits threaded so winding them together gives a shorter spacer right down to thou's  of a inch, if doing the threads is a bit difficult i'm sure a slide and clamp system would work...you can buy 42mm tapes but there in the £200 + range....

[Gina]

If your making your own adapter, go the the extra mile and make it variable in length, say 2/3rds of your required length for a female section and 2/3rds for a male section both bits threaded so winding them together gives a shorter spacer right down to thou's  of a inch, if doing the threads is a bit difficult i'm sure a slide and clamp system would work...you can buy 42mm tapes but there in the £200 + range....

That's a good idea   I shall be cutting the 48mm and 54mm threads so there shouldn't be any problem cutting two more threaded sections.  I'll probably need some practice before I get it right

I'm just waiting for confirmation from Warco - the retailers - that their mini lathe will cut 0.75mm threads, then I shall be ordering one.  I'm looking forward to making my own adapters

Edited November 6, 2013 by Gina

[Gina]

Here is the design of a fixed 48mm to 54mm adapter - 7.9mm thick.  Next I'll design a variable one.

 

[Tinker1947]

i have never done any thread making, but i would think you make the internal and external threads and any rebates on a large lump of bar, then use a parting off tool to cut of the spacer....well i think that's how i would go about it...

Edited November 6, 2013 by Tinker1947

[Gina]

I have this aluminium tube in mind as a starter.  With these options :-

As per the drawing above the OD of the finished product is 62mm and the ID a thread depth under 48.  I calculate the ID of the tube as 44.5mm.  In fact the OD could be left at 63.5mm - it was arbitrary anyway.

I haven't yet worked out how I could make an adjustable version without going deeper into the filter wheel.

Edited November 6, 2013 by Gina

[Davey-T]

Hi Gina,

I believe that aluminium parts can be heat treated to strengthen them after manufacture, don't know if commercially available spacers are treated but would think so.

Also you'll need to buy an anodizing kit now  

Dave

[Gina]

Hi Gina,

I believe that aluminium parts can be heat treated to strengthen them after manufacture, don't know if commercially available spacers are treated but would think so.

Also you'll need to buy an anodizing kit now  

Dave

Anodising is pretty much sorted - I have chemicals and protective wear on order - see this thread in the DIY Astronomer forum

[Sp@ce_d]

... When are you taking orders then Gina...

[Gina]

... When are you taking orders then Gina...

Well, not until I have everything working well then if anyone would like to contact me privately who knows

[Gina]

I now have the scope set up on the mount with EFW2 and 460EX but without flattener.  I have also added the remote focussing motor and had it working and focussing on distant lights.  No stars are to be seen yet but I'm hoping the may appear later this evening

Edited November 7, 2013 by Gina

[Chris]

fingers crossed for you

[Gina]

Just popped outside and seen two stars - yes just two - there's still a lot of cloud but I think it shows promise

[Gina]

Well the clouds have mostly gone away - still some about but I'm not having a lot of success.  I'm trying to do too much at once - I'm too keen to see what the new scope can do and I haven't even got the new mount polar aligned.  Tried doing that tonight but there's cloud low down and AT couldn't solve the rather poor star field.  Now I'm trying to capture the Heart Nebula but I've no guiding set up and no PA so the star trailing is diabolical.  Trouble is with a coulle of hours of clear sky a month it's very difficult

I think what I need to do is take the Esprit off and put one of the Evostars back complete with FF/FR and all the kit and get the PA done.

Edited November 7, 2013 by Gina

[Gina]

I've now gone for binning 2x2 on the Ha with 1m subs to get enough image in one sub and apart from the star trailing the focus is definitely out at the edges and corners but looks pretty good in the middle. 

CONCLUSION - Without the flattener there is noticeable field curvature with the Atik 460EX.

At least the clear sky tonight has enabled me to do one test on the Esprit 80ED even if it isn't very positive.

Edited November 7, 2013 by Gina

[Gina]

Another possibility for connecting the field flattener to an EFW2 is to use just one custom adapter rather than the SW 65mm to 48mm then custom 48mm to 54mm.  So here is a solid 65mm female thread to 54mm male thread adapter of suitable length (18.9mm by my calculation).  Now with 5mm depth of 65mm female thread to take off, I make that 13.9mm.  So with say 12mm of clear metal, it should be possible to build an OAG into it    Alternatively, there is enough optical length in here to make it adjustable so that the back focus could be fine tuned.

Material to make it.

Edited November 8, 2013 by Gina

[Davey-T]

Any news on lathe arriving Gina ?

Dave

[Gina]

Any news on lathe arriving Gina ?

Dave

Not yet - they quote 5 days delivery so probably towards the end of next week.  So far just acknowledgement of order and payment.

[Gina]

To provide adjustment I plan to make a "body" with 65mm OD thread and a reduced end with 54mm thread.  Then two 65mm ID threaded rings (75mm OD) - a long one to screw onto the FF and the body of the core part and a shorter one as a locking ring to screw up to the long one.   No part will have more than 5-6mm wall thickness so can be made from tube stock.  I couldn't find any tube with thick enough wall to make the fixed single piece adapter so went for solid round bar.  The rings will be knurled on the outside for grip.

The "core" part - threaded on the outside - 65mm and 54mm.

The rings - threaded on the inner 65mm and knurled on the 75mm outside.

And the adapter with the rings on but not tightened up.

Edited November 8, 2013 by Gina

[Tinker1947]

I hope you will be wearing something like this when you at the lathe....

http://www.axminster.co.uk/scan-standard-face-shield-visor

[Gina]

I hope you will be wearing something like this when you at the lathe....

http://www.axminster.co.uk/scan-standard-face-shield-visor

Oh yes indeed - already have one of those

[Davey-T]

Joking aside, I had a good friend in America who was killed by a piece of metal flying out of the lathe and piercing his skull.

RIP Lance

Dave

[Gina]

Of dear   Sorry to read that - my condolences to you - nasty

[Gina]

Slight update to the design to make adjustment easier - increased the OD of the thin locking ring.