johnrt

Being on furlough from work has meant I've been able to put some effort in to some Raspberry Pi projects, but not astronomy related unfortunately as I had to retire due to some very large trees. Here's my Pi 4b 4gb with a fan hat & rf transmitter hat on top.

I've been working on a project with 2 radio controlled sockets to control my darkroom enlarger and safelight from the Pi. I used Node Red which is a very simple and intuitive programming environment that works well for this type of thing. Here's my control  dashboard that I can access from my phone when I am printing. The recent addition was adding the f/stop readouts that calculate 1/4 stops of light on the fly based on the base exposure time set by the user.

The time can be set in 10ths of a second and the run switch activates the timer, switches the socket on, counts down then switches off again.  

Great fun  

John

Always looks like a giant fluffy pillow when this is done right, very nice.

Very impressive, I've not visited the DSO imaging forum for a few years and you have certainly upped your game while I have been away. Beautiful image.

Ahaha! More galaxies than you can throw a stick at! My kind of image  

Big Sur running on my new M1 Mac mini, really fast and the mini is barely breaking out the fans for anything I throw at it. Not running any astro apps though

Hello,

Nope, never had a problem with this sort of thing. I used to bin all my RGB 2x2 and shoot a master flat using the Lum filter only at full resolution and then use Pixinsight to register it to the binned images. Sorry I can't be of more help.

Would have to be a fairly bright red light shining directly on to the scope from somewhere to be a light leak.

I used the 1.25" Cheshire back in the day when I was using my 6" RC.

G'day Kirret,

Stick to narrowand imaging with the modified DSLR, you can get a clip in Ha filter and extract the red channel of the image to get a pretty decent mono Hydrogen alpha image.

How is the mount doing? Have you got it up & running now?

1 hour ago, geoflewis said:

If anyone wants to play with my data and show me your versions here are the stacked, Registar aligned, but otherwise unprocessed tiffs for each channel.M81_G_CombineFilesSigMed_reg_cp.tif M81_B_CombineFilesSigMed_reg_cp.tif M81_L_CombineFilesSigMed_cp.tif M81_Ha_CombineFilesSigMed_reg_cp.tif

M81_R_CombineFilesSigMed_reg_cp.tif 3.92 MB · 1 download

I'd love to see what expert hands can achieve, it would be very informative and instructive to me.

It’s been such a long time since I had a go but I may well take you up on this tomorrow. Great image by the way. 

Smashing! 5 minute subs seem a little long, I thought the whole point of these new CMOS chips was that your could take lots of very short exposures, rather than the more traditional method of 10/15 longer subs?

15 hours ago, Viv said:

Thank you for the posting & pics.

Hubby will be treating to me to a pier & it's installation, for a upcoming (& rather big Birthday number ??).

looking forward to it even more, now I've seen this thread ????

Are you going with an Altair pier? They really are great quality and very easy to install. I can't recommend them enough.

The clouds have parted for a little while, so it's now all aligned and ready to roll

A busy afternoon of drilling, resin injecting and tightening of bolts and my pier is ready to go! Great service from Altair Astro and they have delivered a really quality product here, not the cheapest, but for those of us who don't want to build one from scratch this is superb.

... and with the cover on...

Thank you for all the advice above, made it a painless job.

John

22 minutes ago, Davey-T said:

It's not an ordinary mastic gun, it's specially designed for the tubes to mix the two halves together as it pumps them out.

Dave

I did notice that, I have a regular mastic gun at home, but we might have one of those at work, I'll see the man that knows in the morning. Thanks for all your help Dave. 

9 hours ago, Davey-T said:

I used something similar to the screwfix one, worked very well, wll dig it out and see what it was called, the only problem is you need the applicator gun, if you fancy a drive to Swanley you're welcome to borrow mine and some spare nozzles.

Dave

Thanks Dave, I might just take you up on the offer , although it's possible we might have one at work I can pinch for an afternoon I'm told.

Does anyone have any comments as I'm not sure what I'm buying here  

Something like this from Screwfix? http://www.screwfix.com/p/rawlplug-r-kf2-380-tarmac-masonry-resin-380ml/62007

Afternoon!

So the concrete base is poured and ready, I ordered the chembolt sleeves as recommended above and the anchor resin to fix them. Unfortunately the resin is out of stock and the manufacturer cannot supply more, and apparently has no idea when they will be able to manufacture any! The retailer could also not recommend an alternative product! All a little strange. So does anyone have any suggestions of an alternative source for anchor resin?

9 minutes ago, Davey-T said:

Depends on your subsoil, mines clay and I made mine about 18" square from memory and it's been fine, I was going to make it bigger but got a bit bored digging the hole 

Bags of premixed  is good, if you get them from Wickes or somewhere similar you always take back unused ones.

Dave

It's quite sandy down at the bottom of the hole, I had to dig through and old path nearer the top which was hard work. We have a couple of sand quarries very close to us in Borough Green.

I have begun digging the hole for the concrete pad, I will follow the advice above and drill / glue so I can remove the bolts at a later date as suggested. The hole is measuring 38 x 38 x 50 cm at the moment, or in old money 15 x 15 x 20 inches.

So would you bother going any deeper than that? And how many bags of the hard stuff will it take to fill, I'm reckoning on about 8 bags of premix concrete (25kg bags).

Some good advice there, thank you all. Does anyone know what size the bolts are that are supplied with the Altair pier to fix it down to the concrete base?

In an attempt to defeat the trees currently overgrowing my view of polaris I am considering installing a pier to the back garden, the Altair pier looks like a good solid quality product. The idea being that I can align the mount each winter while there are no leaves on the trees and leave in place all year round, my mount already lives on it's tripod permanently outside so no difference there. The pier itself will need to go in a pretty intrusive place in the garden, so one that can be removed easily in case we decide move house or something is essential.

For those of you who have installed one of these, what are your thoughts on this product? What size base did you did and pour to bolt the pier down on to? Any other suggestions are of course very welcome.

John.

26 minutes ago, Moonshane said:

Here's mine

 

Show off

Here is mine in my back garden where I image from, house to my back and trees to the north. It's a good representation of the sliver of sky that I can see from my unfortunate back garden location. It's about 2/3 years old, so the trees are even bigger now!

45 minutes ago, Tinker1947 said:

Its not a black art Colimating a scope, just needs a little bit of practice, coma corrector for a Reflector, focal reducer flatterers for Refractors, go for a 130P-DS in the reflectors easier to use and cheap......

Your quite right it's not a black art & is certainly possible, but for someone just starting out when they want to be capturing some images I think fiddling with collimation would be very frustrating and off putting.

I think the 130P or an ED80 is a good shout. 

An f/3.9 reflector is pretty difficult to collimate, do you have any experience with collimating reflectors? A refractor, like Michael says above is pretty much plug & play. What mount do you have in mind, all successful DSO imaging rigs are built from the ground up. Mount first, rest later!