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cjdawson

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About cjdawson

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    Astrophotography
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    Yorkshire UK
  1. Yep. I figured the same thing about EKOS, but I also have PHD2 installed and both work. I'm planning on tricking EKOS by use a simulator for the mount, then moving the mount manually. Though, the more I think about it the more I'm preferring the idea of using the polar drift align tool in PHD2 to get me close enough.
  2. If your build goes as well as mine, it should be really useful. I'm thinking about modifying my build some more by adding the 7" Official touch screen, but that's not 100% decided, it's something that I'll do after an upcoming start party. Currently, I'm using a 15.6" hdmi panel.
  3. I'm seeing lots of great stuff in your first image. 1. You have good focus 2. You managed to get something fuzzy in the image, which is good news. 3. Looks like you were able to stack the images well, so that means that your tracking/guiding is good too. For next time, I'd recommend turning up the ISO 800/1600 or even 3200 if you can. When capturing your subs try to make sure that the histogram data spike isn't butting up against the left hand end of the graph. A good starting place would be to try and get it to be at least 1/3 of the way from the left, between 1/3 and 1/2 is good. Also, take more photos as well. The more the merrier. You cannot capture too many subs.
  4. Hi everyone. For years, I've been working on and trying to do imaging using my Meade LX-90, over the two decades, I've played with various cameras, a film based SLR, A couple of Canon EOS cameras (30D and 70D), then finally moved on to ZWO ASI1600MM-PRO with filter wheel. I've also switched around guiding gear too, and am using my trusty SkyWatcher ST80, with a Starlight Xpress Superstar as the guide camera. Added dew heater (home made) and myFocuserPro2 and I finally feel like I have a rig that is capable of doing the Smaller object justice. Which is great with a 2 meter focal length scope. However, There are objects out that which are huge. M32, M42 and of course the Horsehead region to name a few. So I just caved an have assembled the following setup.... 1. Sky-Watcher Star Adventurer Pro Pack 2. Sky-Watcher 3/8" Stainless Steel Tripod 3. William Optics SpaceCat 51 4. ZWO Mini Guide Scope 5. ZWO ASI290MM as guiding camera 6. Raspberry PI4 4GB - With Raspbian Buster, Indi, KStars and PHD2 installed. 7. 15.6" LED Display 8. Canon 70D unmodified. 9. 5v USB Dew heater I've got the little adapter so that I cam mount the ZWO stuff on top of the SpaceCat. I've got an M48 to EOS adapter coming so that I can attach my DSLR to the SpaceCat. The plan is for me to run the PI and it's display (And the ZWO Camera) from a USB Battery Pack (30,000mAH) the heater from it's own battery pack and the Star adventurer from it's own pack as well (yes, 3 battery packs) Ultimately, I'll be looking switch over from my PI4, to a PI3 with a touchscreen, so that I can do everything without the need for a keyboard, but for now, I'll stick with what I have working. The idea is that I'll be able to use the ZWO Camera to help me get very accurate PA, also I'll be able to run it as a Guide scope and give the mount a bit of a help to extend the time before trails happen. Today I took delivery of most of the parts, so here's my first impressions.... ZWO Mini Guide scope (already had the ASI290MM) This thing is tiny, with my camera offers a 3° Fov! so that's plenty of opportunity to be able to find a guide star. I don't think I'll have any problems guiding with this setup. ZWO's kit has been good to me so far. William Optics SpaceCat 51. It's a 250mm camera lens, well, that's my first impression, expect that it appears to be extremely well built, made mostly of metal, has all the bits needed to attach to my Star Adventurer or dovetail for that matter. I love that it's got a Bhatinov mask built into the lens cap and that it's also got a dew shield that can be removed and slipped back over the scope for storage. I'm looking forward to giving this a try with my 70D and hopefully grabbing to deep sky objects. The only thing is I didn't realise that the mount isn't a standard T2 mount, it's an M48 thread instead, so had to order an adapter to be able to fit it to my scope, there's always something The Star Adventurer Pro Pack and Tripod. This is a story with many parts. Firstly, I decided to get the Stainless Steel Tripod rather than the aluminium tripod, this simply because I believe that the heavier tripod will be more stable and so should help me get better images in the long run. The Star Adventurer first impressions are a bit of a mixed bag. The wedge feels strong and sturdy, should do the job nicely. The Motor unit should work well and the polar scope may help me with getting setup quickly (I'll have to align that at some point soon) the Dec Plate, counter weight are all good too. I had no problems mounting the SpaceCat, and balancing the setup, there's even plenty of extra wiggle room for when I add the DSLR on to the mix. The there are a couple of parts that feel very cheap and I can see why they've been criticized before by others. The plastic covers for the battery and polar scope feel very cheap, the Battery cover is very easy to slip off. The Polar illuminator is very much an after thought, this thing is really wanting a redesign, it feels flimsy and cheap, there is no proper on/off switch and the brightness wheel is not very sensetive, the difference between full illumination and empty is almost no distance at all. I like that it can be mounted even with the DEC Plate in place. However I feel that it would have been much better to have figured out a way that the LED and brightness parts could have been designed into the motor unit directly without the need have a seperate device. Finally, the Polar scope's lens cover cannot be put on whilst the Dec plate is in use so it's likely to get covered in Dew every time it's used. In my case, I may just do a rough polar alignment using the polar scope, then use the ZWO Camera to do a proper polar alignment so I can put the cover over the polar scope whilst setting everything up. Compared to my Meade LX-90 setup, this is going to be a much lighter piece of kit, much more portable and so should be much much most likely for me to get it out and use. It will be very interesting to find out just how long I can do autoguiding using a battery pack. From my rough measurements, it looks like I'll be able run for about 10 hours before batteries start going flat. That should be plenty for a night's observing. Though, I may also switch employ my tracer battery pack, which should be able to cope with everything for the whole night without breaking a sweat. I'm looking forward to seeing first light on this setup.
  5. Yep. My PI4, didn't to 60°C even when building code and running at 100% cpu usage. I think PHD2 will be enough even without KStars, or anything else. I'll see how that works next time I'm out and it's clear.
  6. Here's the case that I got for mine https://www.amazon.co.uk/gp/product/B07TVLTMX3/ref=ppx_yo_dt_b_asin_title_o03_s00?ie=UTF8&psc=1 It's good enough for what I need..... i.e. stops me zapping the board with static, and the fan stops it hitting the magic 80° throttle. In other news, I figured out that all I need to do is enter the FOV manually, using minutes of arc, which with my ZWO ASI290MM and the Zwo Mini Guide scope, comes out at 161' x 91.2' or 2.68° x 1.52°
  7. That's the PA tool that I saw and was intending to use. However on my setup, as my mount isn't goto, everything is disabled! What's more, when I cheat and put in a simulator, it still thinks that there's 0 x 0 Fov and puts up a warning, even though I think I filled in all the settings. Still figuring that out. Then again, I've now got PHD2 installed as well, so may simply use that instead, as I use that on windows happily. Don't like it's PA alignment tools though, so we will see. My Star adventurer is arriving tomorrow, so it's not like I can test it out at the moment. hehe
  8. Actually, I've been through the script and stolen the parts that I wanted, and modified them as I went.
  9. Getting PHD2 built and installed was painless. It's too late for me to use the AstroPI installer, I've already got KStars installed and working.
  10. Hi everyone. I'm getting a new toy. A Skywatcher Star Adventurer, with a WO Spacecat 51, and a ZWO Mini Guider. The Guider will have my ZWO ASI290-MM attached as a guide camera and I'm planning to use the ST-4 connection to the star adventurer so that I can get really silly long exposures from my DSLR. I alway want to be able to perform Polar alignment using the same guide scope. This will be similar to the technique that I use on my big scope. On my big scope, I use a windows laptop and run Sharpcap Pro to perform the Polar Alignment. It works great. However, I don't want to buy another laptop just to be able to run Sharpcap and PHD2. I have considered getting an ASI Air, however, the cost is rather high, and I'm waiting for a second version of that device. However, the idea of using a Raspberry PI is something that I'm toyed with for a while.... and..... I just happen to have a Raspberry PI 4 (4GB) looking for a good use. Last night, I started off, by flashing up the september edition of Rasbian Buster. Updated and upgraded everything. Then spent the rest of the evening, figuring out how to get INDI, the ASI driver, and KStars built and running. Feeling rather proud of myself as I went to bed with the software all build, installed and configured enough to be able to get the EKOS tool to connect to my ZWO ASI290MM and get an image. I also pressed the button to attempt guiding, and it started the calibration - which is good. However, as there was not a view of the night sky and no scope attached, it wasn't going to work, so I aborted and stopped rather pleased with myself at this stage. Yep. I ended up building everything from source code using Github repositories. Took quite a bit of work as there were lots of librarys that needed to be installed, which the guides that I was following didn't mention. Eventually got everything working though. EKOS does have a Polar Alignment module, which looks like it's in the same style as SharpCap and Polemaster. I'd love to get this working so that I can get accurate PA, without the hassle. My question is..... How do I get the Polar alignment stuff working on EKOS? In addition to this, I'm planning on getting PHD2 installed and built tonight. this will give me the choice of KStars or PHD2, and I might just end up using PHD2 on my PI, but I'm not sure yet. Of course, PHD2 has a PA routine as well, which is something that I'm tempted by.
  11. Welcome to SGL. Using Sharpcap Pro with an LX-90 is a great way of getting excellent PA. All that you need to do is follow the wizard on screen, which will walk you through the process. On the LX-90, the manual adjustment bolts are the Alt-Az alignment bolts. The Az bolts are the ones on the bottom part of the tripod that presses against the tab that sicks out. The Alt adjustment is the four bolts that hold the wedge at the desired angle. You should have a really long bolt that you can use to fine tune the alt, it does this by literally rocking the whole of the fort mount section. Apart from that, the rest of the instructions are exactly the same as any video tutorial that you can find on PA using Sharpcap Pro. I'd highly recommend it. Colin.
  12. You are not limited to the number of images (known as "sub frames" or "subs" for short) that you take. However there are diminishing returns for the amount that you take. What I mean is that if you take 1 sub. Taking 2 subs will 1/2 the amount of noise in the image. Taking 4 will 1/2 it again, and so the sequence goes on, 8, 16, 32, 64, 128 at this point if you want to 1/2 the noise you'd need to take another 128 images. However the longer that you expose, the more detail you can bring out of an image. The exposure time of each sub frame is what determines the overall brightness of the image. The trick is to make sure that you capture as much light as possible without over exposing the image (same rule as daytime photography) How long you can expose for really depends on your camera and the settings. As you are talking about ISO 1600, I'm going to assume that it's a DSLR, so you would be better taking lots of short exposures, I'm talking maybe 15 seconds a sub frame, but the important thing here is to look at the histogram of your first image. It's best to make sure that the big spike of data has been lifted off the left hand side of the chart, that means that you are capturing more data. But most of all, make sure that you don't over let data get all the way to the right as that will overexpose the stars. The rule of thumb is that the more subs you take, the less noise in the final image, and the more that you can process it afterwards. It doesn't matter if you take 1 image with a 60 minute exposure , 60 images with a 1 minute exposure or 3600 images with a 1 second exposure. You'll still end up with 1 hours worth of integration time after the stacking has completed, and when you stretch the histogram of the final combined frame they should all look the same. (That's the theory, there are many caveats, but I want to keep things simple)
  13. I don't know about 2" stuff, for my planetary camera, I use a 1.25" barlow normally my 4x barlow at that. And not much else. For my Deep Sky work, I'm using T-Thread all the way down to the SCT Thread on the scope. The Focal reducer uses SCT Threads, but after that, it goes to T-thread. It keeps things simple for me. As for whether you need to get a focal reducer. You don't "need" one, looking at your moon shot, you should have no problems imaging M42 if you want to stay up very late, (it's just about to become a northern hemisphere object. YAY) You should to able to get a great amount of detail from that. To figure out what barlow's/reducers are worth getting I use the Astronomy Tool FoV calculator https://astronomy.tools/calculators/field_of_view/ For fun, I setup all the field of views for my gear https://astronomy.tools/calculators/field_of_view/?fov[]=312||258||1|1|0&fov[]=312||258||0.63|1|0&fov[]=312||258||2|1|0&fov[]=312||258||3|1|0&fov[]=312||258||4|1|0&fov[]=312||242||4|1|0&fov[]=312||242||3|1|0&fov[]=312||242||2|1|0&fov[]=312||242||0.63|1|0&fov[]=312||242||1|1|0&messier=42 This will give you some idea. If you want to take images of something that's larger than your largest field of view, there's nothing stopping you making a mosaic, just means taking more frames to process.
  14. That's a lovely moon shot. To answer your question, simply put to get a larger moon image, you need to change the focal length of your scope. The longer the focal length the larger the image of the moon will appear. The other choice is to change the field of view of the camera. Essentially have the light from the scope focus on a much smaller sensor. Right now, I'm sure that you are thinking that nethier option is possible, as it means switching out the scope, or the camera. The answer to that is that you can insert an extra lens known as a focal reducer, this will shorten the focal length and make the moon appear smaller. A barlow lens, will have the opposite effect of making the moon appear bigger. Typically, you'll want a focal reducer to be able to take images of most nebula and galaxies. Andromeda is twice the size of the moon for a start! And a barlow is helpful for planets and the moon. I've got 2x, 3x and 4x barlow lenses in my collection, the 4x I find most useful for use with my planetary camera
  15. I'll have to read that article in full as well. I've had a quick scan through some of the top of the thread, but there was not much talk about atmospheric shift. Which is what the "chasing the seeing" thing is all about. I do agree that if your mount is setup perfectly and fully calibrated then it should not need to make many guide corrections. However, making a correction is in my opinion correcting for an error that has already occurred. So with that thought, you can make as many corrections as you like as it will reduce the overall error in the image, but there will be error as a correction was needed. The real question is how much error is acceptable for you? The things that they are talking about in the simulator look to me like things that are mechanical and to do with the mount or optical train. However, the seeing isn't something that we can control hence why it's better in reality to make sure that your exposures on the guide camera are long enough to make the seeing fall into the background noise of the image, rather than a motion that needs to be corrected.
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