Astronix

4 hours ago, ONIKKINEN said:

With the 533 you dont have to worry about exposure time since its a very linear response sensor, even flats in the milliseconds of exposure range will work provided that you take an enormous pile of them.

I have an LED tracing panel from amazon, a really cheap trinket but it does the job just fine. I used to use printer paper between the panel and my scope, but that can actually cause extra gradients rather than solve them, since printer paper is hardly optical quality. White t-shirts, maybe not so much of an issue but in my opinion there is no reason to bother doing this at all, just put the panel in minimum brightness and use some automatic flats taking software to figure out the exposure (Asiair?). If the panel is bright the exposure could be like 0.1s but thats ok, just take 50 and call it a day.

But back to the original question i had, how are your current flats not working? Are they not removing vignetting? Are they overcorrecting so that edges are bright? Do you have a weird circle around the center of the frame, or is it something else?

It looks like I am getting a lot of noise and I thought that flats were taken to reduce this

4 minutes ago, PeterCPC said:

I use a light pad (box) with mine.

Do you have a link for where you bought it?

I think the main thing causing the problem is the light source, what do you use?

14 minutes ago, ONIKKINEN said:

How are your current flat frames not doing the job? Also, what scope and camera do you have?

Some cameras care about exposure times with flats, others do not. Some cameras also have issues with certain gain values (like the 294) not having a linear response so flats calibration is tricky. I am assuming that you are also taking other calibration frames and using them: Matching darks, darkflats (bias is ok for some models). Also this depends on the camera, with some DSLRs you shouldn't use darks at all, so hard to advice at this point.

The scope is a Skywatcher 72ED the camera is an Asi533 pro colour, I also have an EAF auto focused.

15 minutes ago, barbulo said:

IMO, the most important thing is to maintain the optical train used with the light frames unaltered (don´t change focus, fliters...). Also an even source of light is important, hence the t-shirt. Some cameras are specially sensible to short exposure times. With the ASI294MM I use between 5s and 35s exposures depending on the filter (to reach around 30.000ADU - IRRC).

What camera are you using?

Asi533 mcpro 

Hi All,

 I hope everybody is doing well.

Could someone give me an idea of how you they collect their flat frames. I am really struggling at the moment. I have tried the T shirt over the scope with a light source from my iPad method with very mixed results. I have also taken the frames in the morning sky with the white T shirt and had better results. The problem with this method is the weather and clouds 😩

does anyone have a better method? I am using an Asiair to gather the frames and I am getting some good data, but I think that my flats are letting the final image down. Darks and bias frames seem fine.

many Thanks 

4 minutes ago, Elp said:

Out of interest what issues have you had/disappointing results?

well to begin with the usual beginner issues with polar alignment. From there it has been a long list and a long learning curve. The images I have managed, I probably have not managed to get enough good data because I started at the beginning of summer. So the short nights have not helped with ironing out problems. The 450D that I have is fully modded and I have really struggled to get to grips with it. 

In the time I have spent outside I have probably not got more than 10 hours of exposures, but I do feel that I have learned a lot in that time. I am pretty confident that I can crack it with the gear that I have ordered, fingers crossed.😀

Thanks for all your replies it is really appreciated and I have taken a lot in and I have added the usb A to mount connection type (RJ) eqdir cable as a result.

6 hours ago, Varavall said:

For my 2p worth, personally I would go for a Pegasus Powerbox as I don't like being locked into a single manufacturer's products. But for the moment I just run long cables into the house, cheaper and works well as long as the cable run is done well, of course that leaves more budget for the stuff that actually takes the images.

 

Are you actually going to stand by the scope and watch it? If you ae imaging and retreating indoors once set up, any old cheap torch would do.

 

For £2000 why not go for a used ASI2600MC Pro with 2" filter drawer at £1600, then add an EAF (£190 new, less second hand) and filter (£130 new)  and that will leave you £80 to take your wife out for a good dinner or to buy some appropriate, loving gift.

To be honest I don't mind being tied into ZWO equipment if it works pretty seamlessly. I want the head torch for trips out to darker skies one of my mates will be coming with me and we will also take some visual kit at times. I will upgrade as time goes on, but every revue that I have seen of the ASI533 has been very positive.

9 hours ago, Elp said:

It's all a personal thing. Forgot to add if you're currently using a 50mm finder, the 30mm will be a downgrade due to aperture reduction, I went the other way and saw a massive improvement in amount of stars increasing to 50mm from that very same 30mm.

Like all of us we like to constantly upgrade to the next, but I personally stopped short getting a filter wheel or EAF which is why I asked in my first reply if the OP will be with the scope. If you're with it I feel these additions are an unnecessary purchase and will only benefit if you like to stay indoors/remote or have a fully automated setup which stays outside untouched. If you're used to fine focusing manually the focus routine within the asiair works fine, I've done it with all sorts of different optical equipment manually. Focus point does change due to temperature but I've never seen the need to adjust it during a running shoot other than when changing filters which I do manually anyway.

Maybe it's just me, I like to physically be with the setup just to ensure nothing goes wrong with it, even if checking up on it a few half hours/hours at a time.

No I don't intend to leave it completely unattended, I will be in and out and at times will probably spend long periods outside.  

9 hours ago, scotty38 said:

Darn it, after reading the first sentence I was ready to put pen to paper but you managed to rectify it 🙂 🙂

All joking aside "if" you can get by without an ASIAIR (personally I'd recommend NINA but each to their own) then I would put that money towards an electronic filter wheel. In fact if you go for the ZWO mini you'd have money left over and could get the 1.25" L-eXtreme as well as a UV/IR too 🙂

Edit - I'd probably also say the EAF is "essential" as my view is once you've used one, well you know how the saying goes......

Yeah, I have ordered all the kit now and a couple of extras and the EAF was part of the order😀

9 hours ago, Elp said:

If you're really into it, other than the asiair, I would get a mono camera with filters (filters will take up just as much budget as the camera if not more). You'll have the added benefit of imaging narrowband or however you like utilising all pixels of the sensor at the filter bandpass you're using at the cost of slightly longer post processing and project management time. Mono is not necessarily a slower process either due to the full pixel sensor utilisation.

BUT before you go down that sinkhole, try with your modded DSLR first, with DSLRs you have to dither often when autoguiding to average out noise from the camera, even cooled astro cameras also have noise but it's much finer, most people blur/Denoise it out in post processing to get a smooth image.

A mono camera and filters will probably happen for me in the future but for now I am looking to simplify things as much as possible.

9 hours ago, Elp said:

Out of your list I would say the asiair is essential, followed by the 533, and for the time being you probably don't need anything else but will eventually benefit from filters if your light pollution and bortle skies are unfavorable. I was in a similar position to yourself starting with a modded DSLR (which I still have for widefield), once my azgti starting working properly and autoguiding worked (it was around the time I got the asiair it all came together coincidentally), everything just clicked and I haven't looked back. If you're not autoguiding currently you'll also need a usb A to your mount connection type (RJ) eqdir cable. Some people will say the asiair is not essential so I'll reword it as probably the most user friendly and progressive piece of small and light equipment you can add to an AP setup due to having all you need in one unit to work alongside the rest of your AP setup with a simple and easy to use user interface which works seamlessly over WiFi on a mobile phone. Your DSLR I think is also compatible with it (you'll need the right usb A to usb B mini cable, some don't work so well), otherwise you're tied to zwo cameras which is not a bad thing.

That is the reason for the choice of the ASIAir, ease of use. I think that in the short time I have had the gear that I have, I have tried pretty much everything with very limited success. After lots of research I think the the ASIAir should make things a lot simpler.

Canon 450d fully modified, but I struggle with it. I am after equipment that is more forgiving than I have at the moment.

yes I am staying with the 72ED, for now at least. I have not really seen any decent results so I want to see what it can do and take it from there.

1 hour ago, Anthonyexmouth said:

I don't think you'll gain much swapping the guide scopes any why 2 power supplies? Just go for one good Nevada PSU. 

I did think about that, but I also thought it does not hurt to have a spare.

Hi All,

A strange thing happened this week, I managed to talk the wife into allowing me to upgrade my equipment.

I currently have an EQm-35 Pro mount

Skywatcher 72ED OTA

Stella Mira Field Flattener

ASI 120mm mini guide camera on a 9x50 finder scope

what I want to buy is,

1. ASI Air Plus
2. ZWO 2" Filter draw
3. M42 and M48 Connections
4. Optolong L-enhance dual narrowband filter 2"
5. ZWO EAF electronic focuser 5V
6. ZWO ASI533MC Pro colled camera
7. A couple of 12v mains power supplies
8. ZWO Miniscope 30mm F/4
9. Heater bands with intergrated controllers
10. A red/white head torch.

My budget is £2000, I am interested in getting opinions on the choices I have made. Is there anything on the list which you would swap for something different or better?

I have been using a modified DSLR camera and to be honest the results have been pretty poor, I am hoping that this equipment will give me much better  outcomes.

Thanks for reading and I look forward to your comments. 

Hi all,

A quick question, does anyone use a Canon 7D mark lll with the ASI Air plus and does it work ok?

It is not on the list of tested cameras and I am thinking of buying one. (The ASI Air that is) I am just curious as to whether it is compatible or not.

many thanks

47 minutes ago, Astro Noodles said:

Hi

Without filters it is going to be difficult to get great data at this time of the year - it never gets properly dark.

Looks like you have PA sorted, and there is data which shows the general shape of the Nebula. It just looks over-stretched and the black looks clipped. Also, did you correct the colour channels ?

Nico Carver has some useful videos on Youtube which I found really helpful for getting to grips with GIMP. 🙂

 

I do have alight pollution filter so I will try that next.

I did mess about with the colours, but again it was the first time I have ever used photo editing software.

 I will have a watch of that video later, thanks for the help.

1 hour ago, ONIKKINEN said:

Jumping from issue to issue sounds very familiar, and getting any kind of result in the end makes it all worth it!

I will echo the above about taking flats, that will allow you to stretch the image harder in processing without the corners going full black.

Thanks, I will make taking flats a priority during the next session.

M13 it is, thanks for the comments.

Thanks Ian, I will give M13 a go and try to remember to take the flats.

After putting together some kit around two months ago, I thought right here we go get set up the rest should be easy. O’Dear, My first mistake.

focus was my first big issue so whilst I was trying to figure out what the problem was, I decided that I would work on polar alignment. After a few failed attempts I managed to get that done and to be honest I now find that very easy.

 I then ask for help on SGL with regards to the focus issue and after posting some pictures this was resolved. The problem was an extension piece on the end of the field flattener which was stopping me from focusing inward. With that problem solved I tried to take some subs of M51 but as usual the great British weather interrupted me after only 10 x 30 second exposure’s. But I stacked them and messed about with gimp and there in the middle was the faintest image. At least I had got something.

So last week I went out again last week and started imaging The North American Nebula, 

Equipment used, EQM-35 goto mount, Skywatcher 72ED, fully modded canon 450d, no filter used on this occasion. 
I took 56 x 40 second exposures @iso 800.

20 x darks

20 x bias

I did not get any flats.

This was the result any feedback or tips would be greatly appreciated.

There is a dust bunny on there not sure if it is on the camera or telescope.

Great picture 😁👍

2 hours ago, Anthonyexmouth said:

File sizes or image sizes? Are you shooting raw? 

Image sizes, I am shooting in Raw.

53 minutes ago, Daf1983 said:

I had this problem when using the 600d. Make sure that all your files are in the same format (ie fits or canon raw). I found when I tried to mix fits with cr2 files, they wouldn't stack because they were slightly different sizes

Thanks for the advice I will double check tonight, hoping to get out later.

I have been having trouble with calibration pictures coming out in different sizes to my lights and flats.

my darks, dark flats and bias pictures come out much larger and this is stopping me from stacking them.

I am using a fully modded canon 450d and a 72ED scope.

Does anyone have any thoughts, the only thing that I have changed is the exposure time.