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Post by Deleted on Sept 21, 2017 0:28:49 GMT
Hi all,
I've been using an LN300 camera for a few years now from my home in Sydney. While it's served me well, I'm starting to notice more and more its limitations, such as resolution, limited range of control, that it was not originally designed as an astro camera, and its tempermental nature with colour. And of course, there's the light pollution factor. So, I'm thinking if it may be time to upgrade to a new CMOS camera?
One thing I am not seeing too much in this forum are images taken from under light polluted skies, or at least mentioning that the pics are from the such, or that are not post processed. VA is something that I only do from home and at outreach which is also local. My question then is will a new camera be able to give me better control in dealing with light pollution? Do current cameras allow for better control on settings, such as gain, contrast, etc, in order to be able to darken the background more than I can with the LN300? Will the higher resolution provide a better image alone that will help compensate for the LP problem?
The scopes that I have include an 8" f/4 Newt, a 4" f/5 achro, and a 114mm f/4.4 Newt. The mount is an NEQ6, but no, AP is not my thing. VA is my groove. DSLR is not in consideration either.
I am not after "get this camera" or "get that camera". I am after people's experience in working with light pollution. I love Ken's work, but he's lucky to be living out bush... I also understand that not only will I not attain the clarity of Ken's images nor be able to pick up Polarisima Australis from my home, but I would like a clearer image of the Grus Quartet for instance. I guess I should also add that my VA is all Live, not doing post processing.
I was impressed that I was able to see the arms of NGC 1365 and 1566 the other night with the LN300 and 8" f/4 Newt, but these were really more of a tease than anything. I knew what these look like, so I was able to recognise the shape of the arms. However, blink too many times, and they weren't there any more. Get my drift?
Cheers,
Alex.
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Post by Dragon Man on Sept 21, 2017 5:13:39 GMT
Ahhh, Alex, good to see you registered again Yeah, sorry I can't help. As you know, my skies are dark which means I can get away with no gain. And I don't get any artifacts from light pollution. People like yourself living in light pollution often need to fiddle with so many adjustments just to fight the pollution, and smog in the air. Often we hear about Light Pollution in cities but no-one seems to mention the added Air Pollution that contributes to making the task harder. Each time I drive to Melbourne (about once every 3 months) the smog cloud hovering above Melbourne and suburbs is clearly visible from the Pentland Hills (about half way there) and I always say to myself "how the hell do they see through all that crap?". View of Melbourne, from up in the Pentland Hills, about half way there from my house: As for a camera suitable for reasonably fast but also good resolution views I would recommend one of the IMX224 cameras. They start at $160 for a basic model and go up to the mid hundreds for models with fans and up to high hundreds with peltier cooling. Results being posted around the net from people using them in all sorts of light polluted cities show that they do a great job. But, you also need to know that because of their higher resolution (compared to cameras like the LN-300 variants) they require slightly longer exposures (say 10 seconds compared to 5 seconds), and often 'on-the-fly' stacking is needed to clean it up and add detail. But CCD cameras like the LN-300 and others benefit from a bit of stacking too, so it's a null point. I now use 224 cameras myself for my Live viewing and find them fantastic, but your settings will be different to mine simply because of your sky conditions. I'm not going to feed you the old "get this camera" or "get that camera", as it is entirely up to you by seeing results from users, not just by say so. I have tested about 14 different Video Astronomy 'near-live' cameras and have access to all of them and I find the 224 cameras the most practical, and easiest to use. Another advantage over the LN-300 is that the 224 cameras are fantastic planetary cameras, not just DSO cameras. And Planetary & Lunar viewing/imaging isn't affected by light pollution I hope this helps in some way.
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Post by Deleted on Sept 21, 2017 6:15:06 GMT
Hi Ken, Thanks, you have helped. I've written to ChrisV via IIS about this. Chris suggested I ask here I've been looking at IMX178 cameras as their chips are 50% bigger than the LN300 and the IMX224. That's another thing about the LN300, its small chip. I'd even consider IMX174 cameras, but the scopes I have I'd need to add coma correctors for the Newts and a field flattner for a frac, and then you are starting down the slippery road of AP... Much difference between the IMX178 and the IMX224 for what I want? Alex. PS, I've never been far away. Just didn't have much to say This forum has always been my first source of VA info
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Post by howie1 on Sept 21, 2017 6:56:04 GMT
I've been looking at IMX178 cameras as their chips are 50% bigger than the LN300 and the IMX224. That's another thing about the LN300, its small chip. I'd even consider IMX174 cameras, but the scopes I have I'd need to add coma correctors for the Newts and a field flattner for a frac, and then you are starting down the slippery road of AP... Hi Alex ... well you only need coma correctors and field flatteners IF it bothers you. For years I never used one with my f/5 8" Newt, even when I ended up using DSLR (really big chip) for all my EAA! I just didn't care about the oblong stars around the edges. Why not? Because I was doing EAA observing with the camera and not AP. I did finally get a Baader MPCC when I started going long (for me) single 30sec and occasionally 60 sec frames, and was getting pretty darn close to AP quality out of the techniques I used. It was in fact, only because of the great HD / AP quality that I was getting, that the stars around the edges then started to bother me and so I got the MPCC. But even today I often dont bother with fitting the MPCC, especially if they are small targets .... cos I crop out the coma'd oblong stars around the edges to 'see' the object larger anyway! SharpCap, FireCapture, AstroToaster, The Inifity software all allows you to crop while watching the image ... no post processing. cheers, Howie
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Post by howie1 on Sept 21, 2017 7:04:07 GMT
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elpajare
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Post by elpajare on Sept 21, 2017 7:23:12 GMT
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Post by Dragon Man on Sept 21, 2017 11:37:13 GMT
Alex, one of the reasons I like the 224 sensor, apart from its extremely low noise, is its size. At only 1/3" it is usable in any scope without suffering Vignetting in smaller scopes. I have tried several size sensors and the largest I have liked is 1/2", and even with the 1/2" Vignetting starts to slightly show in the corners on small refractors. I prefer the FOV with a 1/2" sensor, but they don't sell one yet that has the low noise and QE of the 224's. The popularity of the 224 cameras, regardless of Vendor brand (Revolution, RisingTech, ZWO, etc), tell us how good it is. Given time a slightly larger sensor will come out with the same spec. That would be great. Maybe it will be the new IMX385. I hope so. The new IMX385 is very similar to the 224 but is 1/2" www.framos.com/en/news/new-pixel-technology-in-the-sony-imx385-doubles-low-light-sensitivity
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Post by Deleted on Sept 21, 2017 13:24:27 GMT
Muchas gracias hombre How do you find both cameras in a live situation? That early image of M33 resembles the noisy image I get with my LN300. Have you been able to use these cameras with nebulae? The large field of the IMX178 is significant. The excellent comparative side by side images show differences for sure. For me, the background colour of the IMX178 is cooler and darker than the IMX224, despite the noise. But again, these are not live screen shots. I've been reading some more, thanks to the links. Chris had also mentioned the IMX224. I'm starting to see that for my purposes, the IMX224 is the better tool. Alex.
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Post by Dragon Man on Sept 21, 2017 17:46:21 GMT
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Post by Deleted on Sept 21, 2017 23:12:08 GMT
Thanks Ken.
The main differences I see between these cameras you've listed, apart from the cooling fan, is the number of frames per second at a given resolution. What's the main difference/advantage of having a much higher rate?
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Post by ChrisV on Sept 21, 2017 23:27:31 GMT
Only need high frame rates for planetary and then it's not essential. Go usb 2 if cheaper
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Post by Deleted on Sept 21, 2017 23:32:24 GMT
Thanks Chris, Thanks everyone for sharing your knowledge and experience with me.
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Post by ChrisV on Sept 21, 2017 23:33:51 GMT
That's acomprehensive list from Ken. The other thing is software. Sharpcap with the zwo (10 pounds p.a. for pro version). Ken and others know the software for the other cameras (and it's free). You'll need a cheap laptop. But that's it - plug in and off you go
Check the fov off 1/2 & 1/3" cameras with your scopes for the different sorts of objects you want to look at. Most of us have 1/3" but Carlos is getting nice things with the 178
You might want some focal reduction ? I love using my 80mm refractor at F4-5 with the 224 - - I just stuck an sct reducer in there (meade 3.3 or 6.3) as I still had them from when I used an sct.
You don't need active cooling for short subs with live viewing. A fan might be good though.
The live stacking software helps control the light pollution. I'll stick up some live stacked shots from semi light polluted northern suburbs around turramurra to hornsby. Should give some idea of what you can get.
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Post by Deleted on Sept 22, 2017 2:04:02 GMT
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Post by ChrisV on Sept 22, 2017 2:18:19 GMT
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Post by Deleted on Sept 22, 2017 4:31:54 GMT
Ok, new camera on the way, Ordered it in RED for all the headaches I'm gonna have working it out... Alex.
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Post by ChrisV on Sept 22, 2017 12:59:21 GMT
What did you get Alex ?
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Post by Dragon Man on Sept 22, 2017 15:52:20 GMT
The 224 quoted above for $295 from Astroshop is the exact same camera that is $160 from RisingTech. Alex, the camera you linked to above is the same camera as the fan cooled model from RisingTech but has a slower frame rate. Also the RisingTech model software has the added feature in its software (RisingSky) of Black point. Handy little tool. The extra $23 for the RisingTech model is well worth it. Also, RisingTech is known for good service and quick responses. The other one (China Scientific Instrument Lab) is an unknown.
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Post by Dragon Man on Sept 22, 2017 15:55:09 GMT
Ok, new camera on the way, Ordered it in RED for all the headaches I'm gonna have working it out... Alex. Which camera?
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Post by Deleted on Sept 22, 2017 21:10:59 GMT
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