rnobleeddy

I wouldn't rule out the battery, but I never had any issues with that combination.

Can't help with everything, but:

- In terms of the noise/banding, if not already, you will definitely want to dither, ideally between every frame, maybe every 2-3 frames if you're shooting short exposures.

- Make sure the screen on the camera is not  on whilst you're shooting, as there can be light leakage (it was an issue on a 550D I had)

- Back spacing is never exact, so you'll need a way to adjust the spacing, and then change it until you get good stars

- For star colours, this was par for the course for me with dual band filters. You're effectively just collecting 2 wavelengths. The centre of the star is overexposed (to collect enough data on the nebula) so that's white, then the edges are one colour or another depending on the colour of the star.  Options are to shoot some shorted exposures without the filter then blend the images, or use the processing software you use to repair the stars.

All in, I'd have been very happy with that for my first image

When I referred to a filter, I meant a solar continuum filter. 

In terms of shorter exposures and stacking, there's no hardware limitations to prevent recording a videos and stacking the frames, but I guess the software doesn't offer that option yet.

1 minute ago, GTom said:

Even at that short FL it produces elongated stars/moons, LoL.

I wouldn't read too much in to that - the images I saw of nebula are much better, and there'll almost certainly be more options around stacking in future.

Haven't been astronomy-ing for a while but saw a YouTube video of this and wanted to come and read the thread. Obviously mixed thoughts, but from my perspective, it's a game changer at this price point. Maybe not right now, but if you think that might be possible in 5-years, I can imagine getting this eating the budget end of the AP market.

On the flip side, I have no answer to the Q about why you'd do this over look at pictures on the internet. The same could be said of all AP - very few of us produce images that are as good as those on astrobin.

For example, I've kept some kit to take white light photos of the sun. I enjoy it. All this needs is a way to attach a 1.25" or 2" filter somewhere, and the right software, and it's going to produce white light solar images as good as my setup, which cost a lot more. 

52 minutes ago, fozzybear said:

it's not like windows and getting the latest version.

I've used Linux for years. My question was why is anyone needs a 64-bit version. Unless you need to use all the RAM on the 8Gb Pi in a single process, I can't think of another reason. And that certainly doesn't seem necessary for imaging.

9 hours ago, AstroMuni said:

I am not as technical hence waiting for Radek. Hope he is keeping well as I havent seen any recent posts from him 😞

I understand the desire to stay away from rolling your own!  Curious to know what's the advantage of getting a 64-bit version?

Is the idea of pixels being "too small" still relevant?

For anyone who images with a range of scopes, isn't it better to get the smallest pixels and then just bin? That way, you can avoid undersampling for widefield.

My logic is:

- read noise on the modern cameras is low, so software binning isn't really a problem.

- Fractional binning allows you get back to the correct sampling rate (last time this came up, there was a suggestion that is was unproven, but empirical results have been good)

- The range of pixel sizes available in modern CMOS cameras is relatively small, and the current generation is so much better than CCDs or earlier CMOS cameras (higher QE, back illumination etc) that the impact of using one of these is far bigger than the gains in avoiding binning

On 21/02/2023 at 22:14, licho52 said:

The picture of the Jellyfish he seems to be so proud of is actually a perfect illustration of "newb-with-5k-RASA-setup" so I disregard his highly smug and opinionated tone.  Yes the filter has some halos but I don't think they're are excessive.  In any case he'd need to put a lot of time into learning processing before halos become the limiting factor in his astrophotography.

Sorry for harsh tone but I found the clip highly disagreeable and detached from the reality.

I'd suggest you watch his other videos. They're very good and I put a lot of faith in his reviews.

9 hours ago, javi89sv said:

Yes, I have to do a test without cc and another with cc. The image on the left is without and the right is with, and as you can see with cc I have the donut or ring effect. The photo below has ABE applied to highlight the problem.

I assume you've corrected flats on both images with flats taken with/without the corrector accordingly?

At this stage, if possible, I'd try out another MPCC III. You may have a bad example. 

Or perhaps someone else has some other ideas. Probably worth a new post- this may have the same impact, but the cause is different. I didn't have this happen with my MPCC II or III with broadband filters.

To offer a different viewpoint...

I had an EQ5 to start with, and then an AZ-GTi for a 60mm APO. I preferred the AZ-GTi and it produced better AP results. The EQ5 was so very bad at guiding in DEC. I can't remember the details, but from memory, the design of the EQ5 leaves out a bearing on the DEC axis and has a shim instead, so is prone to stiction. 

The AZ-GTI wasn't amazing compared to a HEQ5 or EQ6, but was more than good enough for the 300mm OTA I was using.

I'd also say that you do need to guide. A DSLR will need long exposures and neither mount will be able to track well enough unguided for minutes.

My latest camera won't work without a powered USB hub, but the current one I have has too short a cable for the telescope I'm using. The 5V PSU doesn't appear to be a standard one, so I figure it's easier to buy a new USB hub with a longer cable out of the box (life's too short for unnecessary soldering!).

Any recommendations for a powered 4+ port USB hub with a long (e.g. 1m) PSU cable?

Quote

 1 - Why is the filter making my subs so blue?

I don't know why more blue, but any time you chop out vast chunks of the light spectrum, it's best to assume you'll need to rebalance the colours when processing. You can seem from https://www.firstlightoptics.com/light-pollution-reduction-imaging/optolong-l-pro-light-pollution-broadband-filter.html that's it's going to make a significant difference.

Quote

Why are my subs and subsequently my final DSS stacked images terribly vignetted? Is it because the filter is 1.25"? 

That would depend on the camera size primarily, as well as where the filter is placed. More worrying is that your flats should correct this unless you're using a filter that's way too small. In which case all you can do is crop.

13 hours ago, javi89sv said:

I usually use the CLS filter, but also when I don't use any filter I get that halo or reflection in the center of the image, which is not capable of correcting the calibration with flats

This issue was specifically when using by narrowband filters with the older (gen 2 or gen 1) MPCC filters.

So this sounds like a different problem. 

Have you tried ditching the MPCC to confirm that's 100% the cause?

5 hours ago, Lee_P said:

 

“The downside of OSC + dual band is that without processing wizardry, the images produced by the dual band filters are not as good as SHO images from a mono camera”
You need good processing wizardry to produce decent images regardless of what your setup is, so I don’t personally consider this to be a downside. Processing with Ha/OIII plus SII/OIII filters is a bit trickier than just regular dualband, but it’s OK really. I plan on writing a processing guide when I’ve time.

Whether it's a downside or not is a personal thing but from my experience of doing both, getting interesting colour from 12 hours or SHO data is much easier than getting interesting colours from 12 hours of dual band data. And therefore I can knock out a decent SHO image in 30 minutes, whereas I'm still working on massaging the dual band data I collected earlier in January. 

I do use Startools, which may make a difference - it's a got an extremely easy workflow for pure SHO or LRGB data, but it get's a lot harder to add RGB stars, or to use starnet++, and I've had little success in salvaging stars from highly stretched dual band data.

5 hours ago, Lee_P said:

Finally, without wanting to rehash all the usual mono vs OSC arguments, my viewpoint is that which option is best is dependent on the individual astrophotographer and what they’d find most fun to use. I’ve used mono before, but currently have more fun with OSC. Maybe in the future I’ll switch back to mono. It’s often said that mono produces better quality images, but I honestly can’t tell the difference when looking at final, completed pictures. I rarely look at a completed picture of mine and think “drat, I wish I had a mono camera as that would have produced a better image”; but I regularly think “I’m glad it was straightforward to collect that data.”

I agree. Your images above are much better than anything I managed with my SHO filters + mono camera!

Are there opinions on these in general? 

I've just got a 2600MC and I'm using a L-extreme. I like the thought of the H/O & S/O filter as it makes collection very efficient with a OSC - for example, I'd considered just getting an S filter to add S to the occasional target .

But given the price, I do wonder if there's any advantage left over using a mono camera & FW.  I realise this opinion is contentious, but for me is mainly around simplicity, but it's also cheaper. The downside of OSC + dual band is that without processing wizardry, the images produced by the dual band filters are not as good as SHO images from a mono camera.

On 30/01/2023 at 18:46, javi89sv said:

hello, i have the same problem, i get a white circle in the middle of my frame light. I am using a baader mpcc mark III and Asi 294 mc pro. Did you get any fix?

With the MPCC III I didn't really have any issues - you could still see the issue if you stretch the raw data, but it was generally well corrected using flats. 

Don't know which filters you have, but check if they have a direction and if so, if you've got them the right way around- this helped a little with Baader filters.

If you're talking about picking up a second hand modded DSLR for ~£150 then I think that's still a very valid route to get started.  An 18MP Canon such as the 550D is a good shout.

If you were thinking of paying more for that kind of camera from a business, I'd probably suggest looking at the second hand market for a dedicated astro camera. CCDs have largely been superseded so there are some well priced CCDs available, and previous gen CMOS cameras like the 1600MC, at very good prices.

Just take some time to make sure you're getting a fair price - either by looking at closed ads here, or on astrobuysell, or on ebay.

I wouldn't worry about oversampling, as it's easy to work around by binning.

One important point to note is that it's not as if there is a wide range of pixel sizes available. I'm sure someone will correct me, but I don't remember more than a 2x range between the largest and smallest pixels on modern CMOS cameras.

So I'd personally identify my other requirements , such as price and sensor size, then work out what the best, modern cameras are that fit that, and then only at that point would I worry about optimizing the choice of pixel size.

Or what I'm really saying is don't buy an ancient CCD with  massive pixels just because it matches your scope. You will get  worse results than a modern camera!

I struggled with PA when I started out. I'd recommend https://www.sharpcap.co.uk/ - it's £10 and is the easiest PA approach I've seen. I leave my mount in my garden under a cover so it doesn't move a lot, but when I realign it literally takes less than 2 minutes with SharpCap.

+1 for the SVBony rings (e.g. https://www.amazon.co.uk/Guiding-Telescope-Diameter-Finders-astrophotography/dp/B07RQT5CHV)

I wouldn't worry about flex. My experience is guiding isn't particularly impacted by the quality of the guide scope, and even works with less than perfect focus.

I setup two 50mm guidescopes on my 2 OTAs and I haven't had to touch them for over a  year.

You'll probably need to do some research in these exact modeka, but generally the newer sensors are less noisy, which is more important than the megapixel count. But the rotatable screen may well be the most important!

5 minutes ago, Ian McCallum said:

I used to use the RPi Wi-Fi, but nowadays I just use a wired Cat 6 Ethernet cable out to it instead.  As I store the FITS files on an external USB 3 thumb drive, the Wi-Fi used to crash and cause problems, etc.  Now that I use the cable instead, I can have a stable and fast connection, also utilising the USB 3 thumb drive.

I've tried the same, but it means I need to have a door slightly ajar to run a cable. I use an outside plug to power my gear, and I haven't been able to get the powerline ethernet adapters to work through an RCD. 

So I just store stuff on the Pi, then the next day, transfer it over WiFi. Hopefully everyone is aware, but Astroberry sets up a share as \\astroberry.local\ and whilst transferring a large set of images this way isn't fast, I just leave it running in the backgroud.

Didn't read the whole thread, but wanted to add an extra plug for a Raspberry Pi + https://www.astroberry.io/ 

It's cheaper, works with almost anything, and has an easy to use, grown  up interface that (for me) is way ahead of NINA or anything else I've seen on Windows. 

The downsides are that because it's open source + linux, you occasionally need to fix something that doesn't work. And the Raspberry Pi WiFi isn't the strongest, so I'd either get a range extender near your garden or use an external USB wifi adapter with an aerial.

It's not for everyone, but IMHO, it's way ahead of a Windows mini-PC (which I have tried).

4 minutes ago, PeterCPC said:

Sorry but I misposted before. That's exactly what I do use. You say fix the curvature in processing. How would you do that - I just crop normally.

Ah, in that case it looks like a classic case of the spacing being a little out. 

Take a look at this thread - it's usually easiest to get some kind of variable spacer, and on the next imaging session, spend some time at the start systematically finding the best spacing for the flattener.

In terms of processing, I use startools, which has a star repair function that rounds mis-shaped stars. Different tools will have different options, and probably won't please purists, but if it's just stars out there, I'm happy!

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