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Lovely information, thanks!

Hi all Went out very spontaneously last night when I saw that it was clear rather than the forecasted cloud. Not to mention a jet stream right overhead. Getting outside, it was fantastically transparent with fog all around. Starting off, I thought I’d go for some clusters in Cassiopeia inspired by @RobertI . Despite clouds over some of the sky, it was perhaps the most transparent conditions I’ve experienced to date! Just stars upon stars, even with my skies being satellite bortle 7. NGC 654, 659, 663, 436, 457, 225, 189, 129, 7789, M103 and a brief but unsuccessful attempt on IC10. Stand out for me was definitely C10. Just breathtaking, and wished I had @PeterW’s 12.5mm morpheus as a cluster killer. Another highlight was ET. It was my first observation of it, but having seen it on Robert’s post it was a familiar sight which made it a very enjoyable stop! Stopped by the double cluster and a couple of other targets, but then moved to what is potentially my biggest achievement yet. From my generally poor bortle 7 skies, in light polluted London with an 8” scope… M33!!! It was about as diffuse as you can get but my young eyes could just about make something out, and the photo proves it! Safe to say I was overjoyed as I’d always figured this wasn’t a possible target. Right at zenith in wonderfully transparent skies, so I don’t imagine I’ll be seeing it again for a long time but stoked nonetheless. (Can perhaps see some ‘structure’ of sorts in the second, though with the blurred stars there’s a chance it’s just a camera artefact) Finished up on Jupiter and Mars, where I discovered seeing was equally phenomenal despite the jet stream. Most favourable views at 300x, though I do prefer pushing to small exit pupils anyway. Bands upon bands everywhere, just a shame it was the ‘boring’ side! Thanks for reading! Ross (This amount of stars is phenomenal compared to normal) Certainly looks like a spiral there!

Just one imaging run for Mars, as after trying for half an hour it was getting too frustrating 😆 Not familiar with Mars’ features yet, but I believe I’ve got Syrtis major planum and a small dark patch above it. Is that Antapes Colles? 8” dob (manual), asi462.

A couple more with a 25% instead of 40% stack. Still in my ‘play around’ phase of processing with the new cam.

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Last minute decision to go out at 11:30, despite jet stream roaring above. meteoblue predicted good seeing regardless, so I was interested to see whether it was rubbish (in part inspired by @geoflewis’s recent post). Turned out that seeing was actually quite good! Both images with an 8” dob (manual) and asi462. First is a single stack, second is 4 images derotated and it’s always interesting to see how much winjupos helps.

Great report. Is that a sliding counterweight? Looks like a very good idea haven’t come across one before!

Yes I agree. The 462 has better fps and readout noise, but the 662 better qe and no amp glow. I can’t tell from numbers alone which will perform better; does a 35% increase in frames outweigh a 10% increase in qe or is it the other way around? It may even depend on your set up, seeing conditions, length of capture as well. The only real way is to try both cameras out, but there isn’t much material on the 662 yet so you’ll have to wait for someone to come along who’s tried both.

No, quite right that FPS changes for different models but it’s not based on sensor size. The 462 and 662 have the same sensor size (actually 462 tiny bit bigger) but the 462 has quite significantly higher frames at smaller ROIs. At 640*480 it’s 305 vs 227, at 1280*720 it’s 205 vs 157. Certainly something to consider that even if you’re getting a bit more noise per frame you’re getting 14,000 more frames at 640*480 over a 3 minute period. The asi462 is particularly IR sensitive though, and its colour is tricky to get accurate. I’m yet to see very many reports on the 662 and the considerable increase in frame rate of the 462 makes me unsure whether it would truly be an improvement. Maybe you can buy it and give us a well needed review!

ASI462 has a 2.9um pixel size and is a fantastic planetary camera. Not sure what your point about the sensor is, as you’ll always use an ROI that fits the planet for highest FPS so it doesn’t matter if you have the largest sensor in the world or one the exact same size as your ROI!

Start off with andromeda (M31). Depending on your skies you should be able to see it naked eye, or at least see all the reference stars you need. The best way for me to find it is to locate mirach, then go up Mu and Nu until I can see it. If you have an optical finder you’ll be able to see it through that anyway. From M31, you’ll also be able to see M32 just off to the top left and M110 on the other side, although 110 is a bit tricky. Next up for me is M81 and M82. I find Dubhe, walk along until I can see the ET, 32, HD90745 triangle and follow the same distance from Dubhe and ET, along the direction of the triangle hypotenuse until I’m in the right area. Certainly a bit trickier than M31, but you can always figure out your own star hopping route that you might find easier. M81 is fairly bright, and M82 I find is always a bit further than you’d think but it’s unmistakable by its shape.

You’ve got me there that’s a close call.

A good star test just really hits the spot. Does there exist such a thing that is more satisfying 😁

Unprocessed tifs attached. Also realised that on my laptop the images look very washed out and bright. Must keep that in mind next time as the laptop version isn't very compliment-worthy 😆 First is 25%, second 40%. 2022-10-06-2334_1_pipp_lapl5_ap43.tif 2022-10-06-2334_1_pipp_lapl5_ap43.tif

Completely anecdotally, but I’ve found that having a tracked set up can make up for an inch or two of aperture and not much more versus untracked. If you have good seeing that night, then even less (as you need fewer frames). Untracked is certainly more work and can be frustrating/difficult but that makes it far more rewarding. I would suggest trying out the dob a couple times to see if it’s not too annoying for you, because it will blow the 127mak out the water detail-wise. For me, it’s a matter of getting a well aligned finder and getting the planet drifting towards centre with an eyepiece before quickly swapping in the camera. Once it’s on the screen and the planet is drifting horizontally across the sensor then you just nudge each time it drifts out. Regarding the CA and filters, the baader fringe killer supposedly helps with that and I’ve seen people with the same scope reporting fantastic results. No personal experience though. A perhaps more rogue suggestion is trying the 200p on the eq5. Normally a completely outlandish suggestion, but with your only aim being planetary keeping it in frame is sufficient and a good upgrade from untracked. The eq5 is rated for 9kg and the 200p OTA is 11kg so I’d check whether this is to the point where damage could occur, but if it’s just a matter of poor tracking then this could work. Far from ideal but as someone who images untracked with a dob this doesn’t seem so crazy for planetary!

Hopefully I can catch up to you soon! IR imaging from you always incredibly impressive, so may have to try it out.

Thanks! Normally include it in the body text, forgot.

Second light with the asi462. Some fairly good seeing at points. 8, 3 minute captures, cut down to the 5 best derotated and resharpened. GIF is just the 8 animated together. Nice to see the ‘eye’ of the GRS. Will certainly be processing the data more as this is the first attempt. Much different than processing my previous data so I imagine there is more to be had. Will attach the tifs if anyone wants to have a go, but not yet as I’m on a coach!

Hi all Have had a couple sessions now with the asi462, with my untracked 8” dob 2x barlow and ADC. Prior to the asi462, I’ve been using the asi224 so I thought I’d write up a quick comparison. First things first, sampling. With the asi462 and my barlow + adc I’m pretty close to optimum, perhaps a bit over sampling based on UK seeing. With the asi224 I’m fairly undersampled. Onto specifics of the cameras. The larger sensor in the asi462 is incredibly useful for untracked AP. I don’t want to say it’s easy to locate the planets now, but having practiced with the asi224, often on a 800x600 ROI (too lazy to change back to max sometimes), it’s just so much more consistent. Point to the asi462. Accurate colour in the asi462 is a challenge, or perhaps impossible without heading into Photoshop-type programs. This isn’t really an issue, as many of us are probably accustomed to the asi462 colour scheme from how many people use it. At first I was not a fan, but I very quickly grew to like it. Asi462 offers slightly higher FPS. At 800x600 on my laptop, that’s 115 vs 103 for the asi224. Over 3 minutes that’s ~2000 frames which is definitely not insignificant. My impressions are that the asi462 is outperforming the asi224. This will largely be due to the proper sampling, though this is ultimately an imperfect comparison like almost every comparison will be by the nature of seeing variations etc. I’ve attached two images below, the first is my most detailed image from the asi224, the second my best attempt (out of 2 tries) with the asi462. Important to note that with the asi224 I’ve never been able to capture that much detail since. It was the 3rd session with any sort of planetary imaging, and looking back I must have just had absolutely incredible seeing relative to what I’ve had since. As a result, the detail is perhaps slightly greater, but the processing is harsher too so it’s not a fair comparison. The asi462 is still a winner given that I can achieve proper sampling much easier, and if I were to process it to the same degree it would likely be just as detailed.

Wow those are some beauties!! Haven’t heard of Marlique; PRS looking headstock and sg looking body is killer. I’ve got that same Vox pedal as you, though it’s recently died. Have to open it up and rewire as it’s killer with a small amp. Ross

It’s a good question to ask, and quite a tough one to answer. Whilst the stock eyepieces can keep you entertained for a while, perhaps even a lifetime, the vast majority of people will want to upgrade. I’m not sure of the US prices, so don’t know how different the zhummel and 150p are, but I would suggest $100 aside for eyepieces is a good starting place. That said, it all depends on how strict your budget is; if it’s $500 (arbitrary value) for all telescope equipment forever, I would probably suggest a $400 scope and $100 eyepieces, but if it’s $500 on the scope and you could stretch another $50 on an eyepiece or two the month after then it’s that choice for sure. In that analogy the $400 is 5” and the $500 is 6”, hopefully you get my point. Of course, the actual difference in their prices will change how relevant that is, so take the above with a pinch of salt. Eyepieces are something usually acquired over time as you realise what you need and prefer. Whilst upgrading from 5” to 6” won’t be very worthwhile, starting out with the 6” is definitely the best choice if you can buy eyepieces in the coming months. The heritage 150p is also just a very well built and capable scope and you just cannot go wrong. The stray light issue could be problematic for contrast and glare, but I don’t think a shroud necessarily has to be much of a hassle. I haven’t made a truss shroud myself, so hopefully someone who has can weigh in, but I’ve made a dew shield type shroud for my full sized dob just out of a camping mat and it’s no bother. Not the same thing, but there are many people who have DIYed a shroud so it may be easier than it seems. I’ve probably not taken everything into account e.g. how they hold collimation etc., so wait for others to weigh in too but that’s my initial take.

Spot on! Triple coil tapped too so much more versatility than expected from a LP. What’s in your arsenal? Ross

Love it. I raise you two bottles of wine 😁 Once the bottles are finished the lego makes for a good activity!

Asi462 from @Knighty2112 (thanks again!). Going to test against the 224 as I’ll be more properly sampled.

EQ mounts may not be ‘difficult’, but I don’t see any reason for suggesting a beginner gets one as a first visual scope. It’s more work and less intuitive for very little gain. And that’s only compounded with a newt which has eyepiece position problems. Not to mention you get significantly less aperture for the price when you are sufficiently mounted (think about the mount requirement for a 10” newt!!) hence why dobsonians are so good for beginners!