Spaced Out

5 hours ago, geordie85 said:

Your flats are over correcting. I've always just used my luminance flats and they've always worked fine. 

I've never taken separate flats for other filters.

Thanks. Any ideas why they would be overcorrecting ? Do you use L flats for NB too then ?

1 hour ago, david_taurus83 said:

Is that what the flat looks like or has it been stretched? It should be an even grey image unstretched. I never had an issue with narrowband flats and I exposed to around 21k ADU with the ASI1600.

Thanks. That was a single flat frame with the Ha filter unstretched, below is the master flat.

The couple of times previously I have used flat frames with a L filter they looked similar and it worked really well. 🤔

Hi All

I hope someone can help a novice and tell me where I am going wrong please.

I used flats and other calibration frames for the first time recently and got good results with a couple of LRGB images.

My latest effort is my first narrowband image to use any calibration frames and it’s all gone wrong ! I used DSS, added in the flat frames I took for each filter but the final stacked images all show vignetting and when the images are stretched this becomes really ugly all around the edges of the image.

I didn’t take any dark flats this time (I was tired at the end of the session and forgot !) and I hadn’t got round to creating the darks yet. Might this be the issue or should I be doing something different for NB filters ? Maybe different DSS settings ?

Below is an output image from the combined NB filters + flats (showing some ugly edges), and also one of the flats (Ha).

The camera is a ZWO ASI 1600, I used APT with a target ADU of 25000 for the flats.

Thanks in advance for any help you can offer.

40 minutes ago, StamosP said:

Very, very  good! I'm starting to suspect there is something wrong with the optics of my pds...

Is it possible to share a single unprocessed-uncalibrated sub? (the best one in terms of fwhm...)

No probs, I'll DM.

13 hours ago, Anthony1979 said:

Does anyone know which bahtinov mask to get for my 130pds

 

I just got one of these (130P) , a couple of £ more than the ones your looking at but it fits and works perfectly.

https://www.firstlightoptics.com/bahtinov-focus-masks/starsharp-bahtinov-focus-masks.html

On 13/10/2020 at 21:23, StamosP said:

Very interesting...

Have you used it with narrowband filters? 

Last night I used the TS GPU CC for the first time with narrowband filters. Unfortunately I had a terminal issue with my autoguiding, I managed just 3 subs before spending 3 hours failing to diagnose a PHD2 problem ! 

Anyway here's one of the subs with a quick and dirty process. Pacman neb Ha.

23 hours ago, StamosP said:

Very interesting...

Have you used it with narrowband filters? 

No I haven't yet but will do soon, I'll report back !

1 hour ago, StamosP said:

But it shouldn't happen. I wonder if there is someone else who has also used the GPU coma corrector with 130pds and what the results were...

I recently started using a TS optics GPU CC with the 130PDS. I have no problems with it so far, no odd rings like that. I use it with a ZWO ASI 1600.

On 31/08/2020 at 21:22, RobST said:

I just got a used Canon 6d and cant wait to try it with my 135mm lens.

Also have a skywatcher star adventurer on the way.

 

Canon 6D, star adventurer and the sammy lens are a winning combo ! 👍

I use the 6D and star adventurer mini with some wider angle lenses, would love to get my hands on the 135mm tho.

10 hours ago, markse68 said:

It looks like your shed is zapping your scope with lightning bolts! Or is that some sort of wireless power system you’ve developed 🤔😆

I showed it my mate and he said it looked like something out of Frankenstein ! 😄

Imaging with the SW 130PDS on a HEQ5 Pro.

5 hours ago, Whistlin Bob said:

Lots of debate on focusers here. My experience is that the standard one works well with DSLRs but struggles a little with the weight of camera and filter wheel in a dedicated set up. However, with a bit of fiddling (making sure everything is adjusted well and locked once focus is confirmed) I think it does cope. The photos below all came out of an ASI1600 with filter wheel on the standard focuser.

I do wonder if the focuser/heavy camera issue might vary between OTAs, so people get slightly different experiences ?

My own experience (on 2 different 130PDS OTAs) was gravitational tilt that I couldn't fix properly. The best improvement I made was by removing the SW autofocuser I had fitted and tensioning everything up as tight as I could. It was a lot better then but on close inspection I could still see some tilt in images. 

4 hours ago, Jamgood said:

@Spaced Out Looks pretty damn good to me. 👍

Out of interest, what focuser are you using? I'm going to upgrade to something similar when I go the dedicated camera route.

Thanks

As far as I am aware the only easy 'off the shelf' option for upgrading the 130PDS focuser is the Moonlite CR2. All other options I explored seemed to involve drilling holes and focuser bases that didn't match the tube size properly.

I'm using the TS-Optics V-Power focuser. It was an experiment really and is fitted with a custom 3D printed base for now to see how it performs.

https://www.teleskop-express.de/shop/product_info.php/language/en/info/p6522_TS-Optics-2--UNC-V-Power-Newton-Crayford-Focuser---short.html

More info here....

There are a number of ‘firsts’ for me here.

Got my first ever image with the new V-power focuser on my 130PDS, it’s my first step into imaging with a dedicated mono camera (ZWO ASI 1600) and it’s also my first ever use of any calibration frames. It has been a steep learning curve and lots could have gone wrong, however, I am just happy to have produced this colour image !

The processing isn't great, I still have much to learn and I’ve found it quite difficult tbh. I have struggled with star bloating when stretching, wasted hours trying to produce star masks (but just produced ugly  halos), then wrestled with colour balance and battled some nasty noise as I tried to stretch the image to bring out the dark dust clouds (I’m guessing I need more data to smooth things out ?).

Anyway, this is the result so far. I will have another night on this target soon hopefully and see if adding more data helps improve things a bit.

1 hour ago, TareqPhoto said:

So your comment is not a final confirmation then about it, i still can go with it for that reason, money isn't a big issue, my 6" F4 wasn't expensive anyway, and between buying another 6" F/4 or even 8" F/5 then any will be cheaper for me than two 130PDS, right?

 

Thank you very much

I can only talk about my own limited experience with a mono camera + EFW, I'd certainly wait for others with more experience to chip in here, I've not had the mono camera for very long tbh !

If you trawl back through this long thread tho I'm sure there are some images from the ZWO ASI 1600 Pro somewhere, there is also some discussion about tilt.

5 minutes ago, TareqPhoto said:

I can change and upgrade the focuser, but as you mentioned i am just worried that even with that it is still not perfect, i feel like the mono camera and EFW for example is as heavy if not more as the scope itself, so i am not sure going with 130PDS to use a mono and filter wheel will be a good idea, i will wait more reviews or impression from some if they did it, but for now i am not gonna think about 130PDS as an option for my two mono cameras and two filter wheels.

This is what CCD inspector looks like for me (and a test image)..... although not sure how reliable CCD inspector is tbh ?

For the money the 130PDS really is amazing ! I thought about upgrading and going down the TS optics carbon tube route but that would mean much more £££ and getting F4 for a similar FOV. As I don't have an obs and have to set up and break down each night the F4 thing worried me.

Please remember, this is just my own personal experience. I'm sure there must be others on here who have had an easier time with the 130PDS + mono cam and EFW ?

4 hours ago, TareqPhoto said:

Why i don't see images by using a mono cooled camera and filter wheel? I want to know how strong can this scope handle a cooled mono camera with filter wheel.

My own experience is that the 130PDS copes OK with DSLRs but the heavier weight of a mono camera and EFW is just a little too much for the stock SW focuser and you end up with some degree of gravitational tilt in images. Other people may have different experiences tho ?

I have just changed to a stronger focuser to try and solve this, it's still not absolutely perfect but it is much improved. I will be using the Mono camera and EFW over the winter so we'll see how it goes.......

A short time lapse from last night, here's the 130PDS doing its thing......

I've used them both to modify my previous cameras (6D done by astronomiser and 600D done by cheap astrophotography). Both were good I thought.

Hi all

I was really excited to get my first dedicated astro camera (ZWO ASI 1600 Pro). That turned to frustration as I spent months battling gravitational tilt from the heavy camera hanging off the stock SW focuser. I never had this problem with a DSLR.

I’ve now fitted a TS-Optics V-Power focuser. The V-power is designed for heavy imaging gear so I thought it should fit the bill.

The stars still aren’t perfect but they are a lot better than they were. I used an evaluation copy of CCD inspector to check things out and it seems to reflect what I am seeing in the test images. Looks like I might need to work a little more on CC spacing, but I’m actually looking forward to using the new camera now !

Big thanks to Kevin (TheCounter) for supplying a template for the custom base and Steve (teoria_del_big_bang) for doing the 3D printing. 👍 

Just now, Nigella Bryant said:

Looking good, well done, I wondered what the gray boxes were on the pier, lol.

Thanks.

Those are (cheap) outdoor electrical boxes, they house all of my plugs, cables, usb hub etc, they each have a 4 socket gang plug inside and there is also a main USB cable running from the hub back to the 'mini-obs'. These can be switched on and off independently with 2 switches in the shed. Just means I can chuck a telescope and camera on the mount, plug everything in, return to the shed and flick a switch to fire everything up.

On 13/08/2020 at 12:41, Craney said:

That is a very tidy piece of work.  

Like you, I've gone for the exposed permanent pier and  nearby  'mission control' shed.   

It can be a bit exposed to to gusty winds, but it does give you a lot of space to move around  and allows you to buy that 6"  F15 Apo  !!!!    

Thanks

I just didn't have the room for a pier in an obs, the little mini obs/warm room/mission control works really well tho. Like you say the pier is exposed to the elements, particularly wind but our garden is small and I've put tall fencing either side of the pier to try and reduce wind influence a little and also block out a couple of street lights/neighbouring house lights !

I use the little SW 130 PDS on it and that is fine even in a bit of wind, the bigger 200 PDS is difficult tho and only comes out on calm nights. 👍

A cracking start ! 👍

This is a good thread for a fellow 130PDS owner, I've learnt a lot from it.

Hi All

I’ve just been looking through some old photos and I thought I’d share them. I know it’s probably been done to death but last year I built my own DIY pier with some aircon pipe, concrete and brake disks.

I hadn’t got room in our little garden for a proper big observatory shed, so I converted our little old shed in to my ‘mini obs’/warm room. No room in there for a pier tho so it had to go outside ! Anyway, here are some photos of the pier building process from start to finish. The pipe has rebar in it running to about halfway up the pipe and the bottom disk has long threaded rods running down into the concrete to where the rebar ends. I put large nuts on these threads to act as a bit of an anchor. Total cost was under £100.

It took a bit of planning but having a pier is probably the best thing I have done to advance my astrophotography. It has allowed me to carefully drift align the mount and cut down my set up time to a matter of minutes, I just throw the telescope and camera on the mount, plug in all the wiring, flick a couple of switches in the ‘mini obs’ and I’m ready to go !

The mount lives under breathable waterproof BBQ cover when not in use and I run some low wattage boot warmer heaters under there it to keep moisture at bay.

I thought these pics might be of interest or useful to others who may be planning a concrete pier. The guy in the high viz is my mate Andy who helped me with the concrete bit !

5 minutes ago, groberts said:

I'm certainly no expert in the science of calibration but following advice a few years ago, I set ADU at 25,000 using APT and find it works well.

Nor me but I am just going through the same learning process with the ASI 1600 and I have read up a little bit online, it generally suggested ADU 25000 for flats using APT so that is what I have used on my two imaging sessions so far !