London_David

Thanks. I don’t know ukabs — I’ll talk a look. The other thought is... maybe I keep the fork but get rid of the tripod, and use the fork on my iOptron pier... if there is a suitable adaptor plate..

Not totally sure what forum is most appropriate for this post... I have two questions... 1. — Does anyone have experience of putting rings or a dovetail on a Meade OTA? Would anyone recommend one way or another? And any specific products? 2. — Do you think I could sell the LX90 fork mount without the OTA? As the local expert in all things telescope, I’ve been tasked to deal with an 8” Meade LX90 by someone who doesn’t use his (there is a small chance it could be the lx200 but I wasn’t paying attention when I was last visiting). All things being equal, I’d like the OTA to keep for myself since I don’t have an SCT and this is essentially being gifted to me if I want it. However, I have a CEM60 on a pier and have no interest in the Meade fork mount. Also, I think the present owner for sentimental reasons would prefer I got the use out of it rather than just selling everything - though he is realistic too. The mount is in good condition with all the bits and a couple of accessories like a wifi adaptor. I personally just have no use for it. Or am I being stupid and should just sell the thing as a package including the OTA?

Right... maybe I’ll see if I can switch it then.

Did you get the Prominence or the Chromosphere version? I too have just got one this week and trying it out this weekend. I got the prominence one and I’m wondering if I made a mistake. Even with relatively decent seeing (according to meteo blue) I couldn’t see any proms visually. I was recommended the prom over the chromosome by the shop because he said you see more in poor seeing. I’m using it on a WO 71 GT. It was ok when I used a camera but a little underwhelming. At least with a chromosphere one I’d imagine I’d be seeing something on the disk... That said, I may yet be using it sub-optimally...

Not necessarily a great solution since it’s going east not west... but the Flamsteed society attached to the Greenwich Observatory has monthly evenings on Blackheath which is surprisingly good for London. They will have the info on their website, though I suspect with shorter nights they won’t be doing them over the summer.

Hello! Good to have you here. I’m in London which is very bad too (worse than New York and LA) - but I suspect Tokyo might be most light polluted of all!

@laser_jock99 I think that sums it up! I think for eaa it may be a luxury I don’t need. Thanks all! I still like the ability to move the mirror on the ONTC. But again... maybe that’s a luxury not worth it, since for 600 euro I could buy a new ota for visual as well.

@cabfl did you have one? Anything else you liked/disliked? My camera load should be light with under 1kg on a baader steeltrack. Plus this is mainly for eaa on galaxies so I’m going to be using a small chips or ROI. Edge coma I’m not too worried about, focus stability I’m not too worried about since I have a motor focus and exposures are going to be 0.1s - 30s, mainly under 10. As I understand it, collimation stability is more key for me. Do you think that will still have issues for flexion and expansion? I saw someone on CN with tilt problems but that in the end seemed to be his camera to focuser.

Thanks all. I currently have a 6" f4 which I've liked a lot. But you know... aperture... I have a sesto senso and actually, @iPeaceI was thinking of doing exactly as you have and switching the UNC focuser for a Baader Steeltrack. Did they charge you extra for it in addition? Or just the price difference of the Baader? My gut is certainly that the extra €700 for the ONTC is probably not needed for what I'm using it for. The main thing I like on the ONTC is being able to move the mirror to change back focus. I want to pair whatever I get with the Ackerman corrector/reducer that they have to take it to f2.9. However, if I'm thinking if I get the focuser set for the 90mm backfocus offered, I can use an extension tube if I want to use the scope without the Ackerman corrector. I spoke to TS and they said they would build the scope so the draw tube is always out of the tube when in focus. I suspect too that I wouldn't notice a huge amount of difference for EAA use, but I'm tending towards the UNC for a couple of reasons. I'm not scared of collimation, but I am scared of collimation stability and focuser stability on the scope. I suspect from above that the UNC will be good enough - especially with the Steeltrack. Plus this is for EAA with small chip cameras doing short exposures so I feel I should go carbon fiber because of weight (I have to lift it on and off each night) and physical rigidity over the steel. It's expensive, I think it'll be a small difference but a nice luxury to enjoy.

From my reading the Atik post doesn’t explain that the comparison to make is signal to noise ratio per micron, rather than just per pixel, since CCD pixels tend to be bigger. While read noise increases with signal because it is done after, it does so significantly slower than the signal increases. This is particularly relevant on CMOS since read noise gets down to very low numbers compared to CCD. This SharpCap post has a longer explanation with the maths on it (the talk I posted in this forum on goes into a lot of detail on imaging including this which is interesting and has less maths...) https://forums.sharpcap.co.uk/viewtopic.php?t=262 Atik until recently only made CCD cameras and would have an interest in putting CCD technology in the best light. What’s in the post is not wrong, as I understand it, it leaves out part of the story. Robin Glover who developed SharpCap is neutral to CCD or CMOS technology since the software processes both sensor types and was a non profit hobby project until recently. Specs don’t tell the whole story of course but in QE the imx290 is rated at greater than 80% QE and the Lodestar at 77% so very similar. But the pixel size is 8.2 on the Lodestar microns compared to 2.9 microns. So you can bin (2x2, or 3x3) and get more signal over the same size of sensor area with the imx290 chip than the Lodestar. Which, given everything else being equal, makes it more likely you will pick up fainter detail, and the option to sample at a higher rate. All the same, my original point is that for a newcomer something like the asi290 mini is £150 cheaper than the Lodestar. So even if you think both cameras can do roughly the same thing, the asi290 is probably a better bang for your buck. I’ve been happy with mine and I’ve found it very easy to use with SharpCap which sets everything automatically depending on your light pollution and individual sensor readings. The Lodestar is a good camera and will give you good results (reading in the other forum you can see excellent interesting observation reports using it). The SLL software is clearly excellent (and one of the very few options if you want to use a Mac), however there are newer cheaper options that are at least as good. The sad truth is sensor capabilities are probably going to be a small difference relative to seeing and light pollution which will be a more significant restriction on what you can see. I think any camera talked about here can give you good observing results (and you can see those results in the forums). As Martin says the important thing is to enjoy using the kit. @SIDO If you check out the astronomy tools site it’ll give you a sense of over and undersanpling with your equipment and seeing but I would not worry too much about oversampling and be careful about undersampling. As mentioned you can always bin if you are oversampled.

I personally would not get a Lodestar now. While you can still get great observations out of it -- it's quite old technology -- so in terms of what you pay for what you get it's not good bang for buck. I would look at the ZWO ASI cameras - I have been very pleased with mine. I've ordered directly from them and they've been helpful and responsive on the forums too. You can also buy from local vendors too if you want to have extra security for faster returns. I have the ASI290 mono and the ASI294Pro colour. Rule of thumb on specs for these CMOS cameras is that you want low read noise and high QE. Pixel size can be small but you can bin at effectively no loss. There are a few options depending on sensor size which will determine your field of view (you should do a check with your equipment and proposed camera to see FOV on astronomy.tools). If your considering the Lodestar mono, I'd strongly recommend the ASI290 (or other IMX290 chip camera). For my money it's still much the best EAA mono sensor around in the amateur price range. The USB2 mini is about £300 and the USB3 version £350). There are other options but I've not tried them and tend to be more favorable for AP. https://www.firstlightoptics.com/zwo-cameras/zwo-asi290mm-usb-3-mono-camera.html

I’m upgrading and I’ve decided on one of these two scopes: 10” f4 1000mm TS Photon metal https://www.teleskop-express.de/shop/product_info.php/info/p10225_TS-PHOTON-10--F4-Advanced-Newtonian-Telescope-with-Metal-Tube.html 10” f4 1000mm TS UNC carbon fibre https://www.teleskop-express.de/shop/product_info.php/info/p5034_TS-Optics-10--f-4-UNC-Newtonian-Telescope-with-Quartz-main-Mirror-and-Carbon-Tube.html Has anyone any experience with carbon fibre and metal tubes on a Newtonian? Or quartz v regular glass? Or any experience with the TS scopes? I will be mainly using this for eaa with a asi294pro and an asi290. Cost isn’t a particular issue, except I’d rather not waste money if there’s not much difference. I had read that metal cools quicker but is less stable, cf is slower to cool and more suceptable to dew, but more stable once it’s at the right temperature. I had also read that nine times out of ten you won’t tell the difference in performance, only on nights of great seeing. So I think the only difference is down to 2kg lighter and the properties of cf v metal... Or if anyone has used the ONTC version and can say why the extra cost is worth it? Any other experiences to note?

I had exactly this problem and with some digging on solar observing polar alignment I figured out a way to do it roughly. Noted here in this thread: That said, it’s not super accurate. It’s about on par with a decent visual alignment... when it works. The problem is that you are relying on the accuracy of your mounts Goto system. If it’s good then so will your alignment accuracy. On a good day, my EQ3 would give me 10-15s exposures on a 750mm focal length with the ASI290. I found that the best way is the laser pointer method in that thread. Attach a laser pointer to you mount in a very reliable place. Do an accurate align once then mark where the laser points to. That should get you most of the way there. You can then fine tune depending on your needs. Much of the time for EAA I align as I described in that post — even when I can see Polaris. That said, for real AP you’ll need something more accurate.

I have a compute stick with the m3 chip and it’s great. It’s the same power as a surface pro 3 and runs windows 10 nicely. Both the atom and the m3 will work for eea (and ap) however, if you have a large sensor camera you’ll want to go with the m3 version due to the larger memory and faster chip. On smaller sensor cameras like the asi290 the atom is perfectly adequate. I went for the m3 version because it gave me room to expand and I knew windows 10 would be smooth. Windows on an underpowered machine is always horrible. If you do some digging on this forum and on cloudy nights you’ll see quite a few people using the compute stick in various configurations. I have my compute stick headless at the scope and it connects to the main WiFi. I then rdp into it from my iPad Pro which makes it a great wireless experience running sharpcap, motor focus and the mount wirelessly from my iPad. I can walk around anywhere inside and outside my house and have full viewing and control from the iPad since rdp runs across the main WiFi. So long as the WiFi reception is good the response is pretty much instant. If you crank up the resolution to the almost 4k native iPad screen resolution it’s a bit sluggish but still usable. Most of the time I stay streaming at hd. 4K is nice for detail on a wide field, but most of the time I’m zooming in anyway. It also runs off a usb c power so I can use a standard lithium ion battery pack in the field if I want and be completely wireless there too. The compute stick is a really great compact solution. It’s not the cheapest, but there’s nothing smaller that I know of that can do the same. The Nuc form factor machines are also good, though much bigger, they are cheaper. But you can’t run them off a regular L Ion battery since they tend not to have a mobile chipset. If you search my old posts I’ve outlined exactly the items I have and what I’ve been doing with them. I think I have exactly the m3 stick you’re looking at. edit: just found an old post with all the details. It’s a bit out of date since I’ve made a few tweaks upgrades and additions... but the core compute stick bit is all the same.

I tried my AZ-GTI with my 150PDS as an experiment one night and it worked fine. Estimated weight was 5.6 for the OTA, 120g for the camera, plus another 150g for the finder. So properly overloaded at almost 6kg and... I wouldn't have called it super stable, but I balanced it and worked and tracked fine. Using wireless control I never had to walk near it and I wasn't too worried. Crucially (and this is why I did the test) the setup time was about 90 seconds rather than the 23 minutes it takes me to setup my EQ mount. The only issue I've had is the weird software issue noted elsewhere where it sometimes stops tracking unless you restart the app. I have been using the experimental firmware though and haven't updated it. It was working fine before that.

I’d definitely buy an eqmod cable for the AZ GTI. Also, does anyone know where to buy a counterweight bar for eq mode? I’ve read it fits an eq1 bar but I can’t find that to buy separately. I don’t even know if the eq1 bar is correct. To date I’ve bought 3 different bars now and none of them fit. Very boring!

I have a GTI AZ Mount and use iOS. I’m sure it’s the same hardware as in the Wi-Fi adaptor. I really love the GTI mount. The two device thing is irritating but it’s not too bad. I’ve been surprised at how good the app is actually. It’s quite basic looking but it works quite well.