JohnC64

Hi Oli - Welcome to SGL 🙂

Great result - especially using your guide cam.  Look forward to seeing your images when you get your new camera

John

I used these M12 chembolt sleeves to fix my pier in.  You just drill the concrete and fix them in with chemboltx adhesive and then when its try you just bolt down into them.  If you need to remove your pier, it doesn't leave anything protruding from the ground.  

http://www.sealantsonline.co.uk/ProductGrp/Chemfix-chembolts-tarmac-asphalt-anchor-sleeves

My pier is fixed to 80cm x 60cm x 80cm concrete block,  but i live out n the fens and the ground is 'mobile'.

Cheers John

Hi Scorpious,

I really like the boarding that you have put on the side.  That must have taken some painting!! (Willow green is definitely the colour of choice for the discerning observatory builder  )

Wow - Just looked at your roll off wheels.  They look incredibly solid and well built.  I'm sure that they will be able take whatever weight that you put on top of them.

In the coming week I'm hoping to build the door on my obsy and finally get a  sealed structure.  I hope that you have more luck with the weather to get your roof on.

Best regards

John

Hi Scorpius,

My vTracks came in 9ft lengths.  I just screwed them down end on and there isn't a noticeable transition between the pieces when i move the roof. The Trick that I picked up on here was to screw one end down and then move the roof over them to get them to self align.

"Wow" is all i can say is about your build. you are doing a stunning job on putting your observatory together. It looks a lot better than some house builds that i have seen!!

Cheers John

Hi Scorpius,

Thats looking very nice and very solid looking too.

Cheers John

Works like a charm.  Had the demo from Grant at the I.A.S and have been having a look every day since then and it appears to be pretty darned accurate for me.  

Suggestions:  As well as the "clear clouds" button in the April 1st 2015 update - could we have a "Turn moon off" button too.  Would have come in handy last night

John

The best   M31 I have EVER  seen!!!!!!!!  Stunningly impressive piece of work.

John

If you are looking for something of an exact size, then take a look at laser master  ( http://www.lasermaster.co.uk/metal-laser-cutting )

If you select washer in the cutting type, and specify a inner and outer diameter, it will give you an instant price.

I have used them for small custom aluminium washers in the past. They take a while to come - guess it depends on what material and thickness they are cutting on the day to make a batch job up.

They custom cut mild steel up to 15mm thick and stainless 304 up to 10mm.

It will cost a little more than a disk brake - but you can get exactly the size you want.

Hope this helps 

John

Hi Gina,  had a look at the original files and to me it looks like the blue channel image was slightly rotated.  When I registered them in PI and RGBCombined them, and then AutoSTF'd them, they came out with nice round stars. (Albeit with a bit of seeing around the stars )  I think that your optics are fine. :-)

John

I did find this one,which is a bit thinner http://www.teleskop-express.de/shop/product_info.php/info/p5249_TS-Adapter-65mm-to-M48-for-Baader-Steeltrack-65mm-thread.html and combined with their M48 to to

T adapter gives an extra 3mm. I was going to wait to see if I could find it in one adapter though

Hi Gina,

probably just being overly cautious  here, but the brighter stars appear to have dark notch in them, (at about the 7 O'Clock position)  Is the OAG impinging into the light train a touch? Or is it just the low resolution jpegs?

Great image for just 5*1mins in Ha

John

Edit - just read back - no OAG.

As one of the adapters for the Esprit, Would FLO be looking at a M65 to T adapter?  That would solve a lot of peoples problems (Mine included!!  )

John

Had an issue with the field rotator - (it didn't). Ed At Harrisons has been superb and has sorted it for me. A big thumbs up from me to them.    

As you have taken pictures up the glass and down the focuser, the only thing i can think of is something down towards the camera?  But as this is screwthreaded, it doesn't seem an obvious candidate.

John

This  is really weird.  Wouldn't that  indicate something intruding on the light path on the outside of the scope? But there was nothing visible on the earlier pictures

Have you tried visually with a hi-magnification eyepiece to see if the effect is observable visually too?

My esprit comes back on Monday  So will look up the glass to see if i can see any likely candidates.

John

I've been using a 1100D now for a couple of years.  I bought it modified and it has been great.  As you say the chip size is APS-C which gives a lot of area.
In terms of noise, i  find that during the winter, it is not a problem.  During the summer, i tend to knock the ISO down  to ISO 400 which seems to help.  Because of its popularity as an astro camera, you will find plenty of add on extras, like clip in filters, TMount adapters etc readily available 

One thing to note is that the DLSR does  do some internal processing on the images so if you look closely you will find some dark halos around stars( only if you zoom into the pixel level do you see them)  I also notice a very slight "red shadow"  on very bright stars(especially on red stars). probably caused in part by having the mod with a shim so that autofocusing still worked.  If this is going to be an Astro camera only then you probably don't need the shim.

I've only used this camera at around the f5  mark and it performs well.  At f10 on the c9.25 then your sub time will have to be longer to gather the same detail - Or an alternative way of looking at it is that your signal to noise level will be lower so noise will become more of a factor.

There are plenty of  adverts for modded canons on astrobuysell  for around about £250 - £300 so you may be able to pick up a bargain on there.

John

3mm for the thin ring sounds ok to me Gina.  How much stress is it going to be put under? Hopefully not much.  Get a 3mm piece of Aluminium and see how sturdy it is would be my suggestion.  You could retain the 2mm adjustment then if it feels ok

John

You should be able to get a zero length M48 to T2 adapter.

http://www.teleskop-express.de/shop/product_info.php/info/p2839_TS-T2-M48-adaptor---zero-profile.html

And with a T2 extension plumbed into that, then should be able to get it exact if using some delrin spacers http://www.firstlightoptics.com/adaptors/baader-t2-delrin-spacer-ring-set.html

how about this
http://www.teleskop-express.de/shop/product_info.php/info/p4041_TS-Adapter-M54-to-M48--2---filter-thread---M48-Adapter-for-Filterwheels-and-Filter.html

Or is it the wrong way around. 

sorry to hear about your goats Gina(I keep sheep)  I enjoyed your test images of them when you were doing test shots on the debayering
John

its not good news is it :-(  - i have some spacers on order that have been dispatched - on the back of confirmation from Skywatcher.  Guess we need to confirm what the distance is now

are you thinking of taking SII on this target??

Right...  Been reading Cloudy Nights and a reply from Skywatcher USA seems to confirm that the back focus required for the Esprit 80ED flattener is 75mm.

I'm always confused about whether adding filters in the light path increases or decreases this requirement but going by this thread on Cloudy Nights it wants increasing by 1mm for the 3mm thick Astrodon filters.  So that's 76mm then.

Hi Gina,

Thanks for the link, I wasn't sure if it added or subtracted too.  Right think I can start ordering extension tubes now :-)

John

looks like JTW are now offering debayered cameras on a commercial basis

http://www.jtwastronomy.com/products/monochrome.html

and also a primer on how to debayer

http://www.jtwastronomy.com/tutorials/debayer.html

John