ollypenrice

Exactly. Olly

I thought he got off lightly!!! lly

Very obviously, the vendor of the camera hasn't the slightest clue about how to take or process astrophotos so don't panic about the awful quality of his/her images. I might have a slight concern about the cross-hatching in what is supposed to be M31 but the subs must be so short as to tell us almost nothing. This camera will be a little slow but, for £400, you have a proper astro camera from a very serious manufacturer of well made, long-lasting instruments. Just take your time and shoot for long enough. It's impossible to give a minimum integration time but I would say that, from a dark site, the best-case scenario would be 5 hours. Don't balk at 10. That's astrophotography. Olly

Mine was with TEC140 and Atik 11000, Rodd. Olly

Here's another one. Two 'holes' with fingers of gas ad dust emerging from them. C'mon, these things are real! Olly

That's a really great job, Rodd. Lovely. Ha is a mixed blessing in a broadband M42, I feel. The fact is that some features are notably absent in Ha, especially this curious 'finger' poking out of a hole. It's not entirely absent in Ha but it has lost much of its definition. The other thing about the Ha in the surrounding region is that it mirrors the brown dusty stuff and I think that it's more natural to present this as brown dust rather than in the emphasized red of Ha. My own feeling was to include the Ha more lightly than I would usually do but I'll be interested to see how you feel about it. Olly

Your image is a fair approximation of the naked eye view from a dark site, except that the background sky would be darker. (It wouldn't be a dark site if that weren't the case!) It can be seen as a short, faint, thin streak very much as it appears in your picture. It takes a large telescope to make out the distinct dust lanes but a large telescope can, because of its focal length, only show a small portion of the galaxy so, in some ways, the binocular view might be considered the best. The key thing is to find a dark site with good transparency and with the galaxy high in the sky. This is important. Olly

Peter is right. The moon is a disaster for photographing nebulae because this requires the faint nebulosity to be made visible by 'stretching' it in processing to brighten it by more than we brighten the background sky. That's how we separate it from the background. Once the background is as bright as the nebula (to give an extreme example) there is nothing to separate. Nebula and background become one. It is possible to photograph emission nebulae in the hydrogen alpha emission spectrum during the moonlight because sufficient contrast between moonlight and nebula is created by an appropriate Ha filter. Olly

Attractive in that it won't leave you short of a colour, but less attractive because it is slower and because it is inefficient in Ha, which can be shot in moderately bright moonlight... Olly

I remain intrigued by the number of deep sky objects which have replicas of themselves nearby. Check out the Witch Head nebula in this sensational Orion constellation image. It has a very obvious twin. https://www.astrobin.com/yjd5ep/?q=orion constellation samyang 135 Olly

Yes, as above. You would certainly do better to take longer sub exposures if you can. This is less true of very modern cameras with low read noise but that probably isn't what you're using? We do take a long time over our pictures in AP, though. My own Andromeda probably had about 20 hours. Olly

Absolutely not the Startravel 120. Fast F ratio, budget refractors are about as bad as it gets in astrophotography. Also, the camera has a tiny chip, meaning you'll need a very short focal length to fit deep sky objects onto it. If you can't run to a camera with a bigger chip, I would keep your focal length right down. A prime camera lens, possibly an old one, provided adapters provided adapters are available to fit the camera. If you don't match chip size with focal length you end up with a minute field of view and many deep sky objects are actually very large. Some of the best images being published at the moment (the best bar none) are coming from the Samyang 135 lens. Olly

If you replaced the term One Shot Colour with the far more accurate, Half a shot green, quarter of a shot red, quarter of a shot blue, you'd get a more accurate idea of what's going on. If we slightly over-simplify, we can say that a colour filter blocks 2/3 of the light. Red blocks green and blue, green blocks blue and red, etc. It doesn't matter whether these filters are in front of a mono camera or placed over each pixel of an OSC camera: that's what they do. This means that an hour's red, an hour's green and an hour's blue in a mono camera is equivalent to three hours in an OSC. (I'll give a couple of caveats at the end but that's the gist of it.) So, at this stage, the mono and OSC are passing the same amount of light in the same time and are equivalent. Enter the luminance filter: this is not available to an OSC because its colour filters are fixed. In just one hour the luminance takes an hour's red, an hour's green and an hour's blue. It can't distinguish between them but it doesn't need to, that distinction being provided by the colour layer. So... RGB and OSC are equivalent in light per unit time but LRGB is faster than OSC by at least 20%. If shooting Ha, which you can do in both, the mono camera is four times faster because only the OSC's one-in-four pixels can pass Ha (the ones under the red filters.) Caveats: - OSC green is actually wider than just green and takes light from a wider spectrum because it serves a 'luminance' function in daytime photography. However, we are rarely fond of green in AP and might like less rather than more. - Good quality RGB filters are more efficient than the tiny filters placed over OSC. - A naive view of OSC will suggest it has 1/4 the resolution of mono because of the 4 pixel array (RGGB.) In reality, subtle de-bayering algorithms replace most of this 'lost' resolution by interpolation. There's little real-world difference. - My purely subjective impression, having tried both, is that CMOS OSC is better than CCD OSC. I don't know why or whether this would stand up to real scrutiny. - Modern Dual and Tri-band filters make OSC much more attractive. Olly

Truly gorgeous with a subtle touch both on the brightnesses and the colour. This is much better as a NB target because the reds dominate completely in broadband. Olly

Thanks. The scope was a bequest from a friend, Alan Longstaff, and in showing it some respect I feel I'm doing the same for him, even if the handle will only serve occasionally. Olly

This lens is on my 'perhaps' list and, if I go with it, I'll pester you for advice, Rob! Olly

Ah, gotcha! Yes, that would be a good idea. Thanks, Olly

I used to guide with a Mono Atik 16ic on one rig and an OSC 16ic on the other. Their performances were identical. Mono is preferable, certainly, but I found no real-world difference. Olly

Thanks Lee, but I won't be guiding the 14 inch, which won't be doing DS imaging. You're right about a bit of planetary imaging, though. I've no idea what the current top camera choices are but it would be good to look into them. I'm really impressed by the view in the 14 inch. It was significantly better than I was expecting and I really can't fault it. As you say, it will go on and stay on except when something needs fixing. Yes, my mount itself is OK, I think. It was working fine with its original handset but has proved not to work with the replacement, which is also called Autostar II. It goes in the right direction when I try to align it but misses by about 20 degrees and doesn't get any better when synched. I think it must have a different protocol and I hate faffing around with that kind of IT issue! It wasn't very stable, either, with a long damping time. This isn't too good for beginners because they struggle to find focus when they're looking at a trembling star. I'm looking forward to having it on a stiff mount and to doing more visual observing again. Olly

My imaging is now robotic and, besides, there was a moon and cloud. I've got twenty years of never going to bed to catch up on!!! lly

I'm going to use the OTA for visual observing, both for myself and with guests. It's going on a MESU 200 which has a payload sufficient for a second one. I have a Moonlite focuser which came with another deal but which wouldn't fit in the fork mount, so I think the Meade will now do great stuff. Less vibration and a locked mirror with nice fine focus. EPs are 13mm Ethos and 26mm Nagler at the moment but I'm feeling the urge to splurge - on a Pentax 40mm. First it has to survive being lifted onto the mount, though, so I added a removable front lifting handle for such occasions. I'll do this with two helpers, for sure. Olly

It's 14 years old but you're still right, progress has been enormous. Olly

The magenta is still there for me. I found that altering the hue to minus twelve in the blues was a one-cklick fix: Olly

I just ordered this twin filter and wonder if anyone's tried it. The moon is more than a bit bright in our 14 inch SCT and I managed to lose my original fixed density filter somehow. I guess I should have asked before ordering! Olly

Popped out for a quick nature call before going to bed last night, looked up and there was a nice little bolide in all its glory, streaking towards the SW. It fragmented neatly at about 45 degrees above the horozon. No colour but still very nice. It makes you wonder how many we miss! This was at about 8.30 pm UK time, 9.30 pm here in France. Olly