Bluemoonjim

Thanks for reply Onnikinen. My trips to dark sky usually involve a couple of nights away, hence the 12hr minimum. I don't usually shoot more than 5 or 6 hours (if I'm lucky) in one imaging session, more often around 4 hours, so I figured 12hr reserve would cover the two nights and some.

All 12v apart from laptop. Dew bands are for 102mm scope and 50mm guide.

Hi I'm looking for a portable power unit that will reliably power my rig over a 12 hour period (minimum). My rig includes: powered mount, imaging cooled camera, guide camera, slave mini pc, laptop, dew bands (2 or 3) Have been looking at the Eco Flow range of power stations but not sure which would best fit the bill. Anyone out there using one of these? I would prefer not to go the diy route but I'm open to suggestions

Those are beautiful images. Seems to be a growing trend for cloudy nights in the UK over the last few years. Global warming? With so many cloudy nights, growing light pollution and ever increasing satellite activity it has made me question just how much time, effort and money it is worth investing in this hobby. Mind you, I am a 'glass half empty' sort of bloke!

Does anyone know if it is possible when saving auto .tif format to change the default 100 dpi setting (ie. increase to 300dpi)?

TS Optics 72mm Photoline. https://www.teleskop-express.de/shop/product_info.php/language/en/info/p8866_TS-Optics-Doublet-SD-Apo-72-mm-f-6---FPL53---Lanthanum-Glass-Objective.html

I would recommend having a look at www.urbanastrophotography.com. Lee, who created the website, has some clear thoughts on hours of data to collect.

Just seen you post Vlaiv. Will read the link. Good stuff

mmmm... interesting. It brings into question what we are actually trying to achieve when imaging. Is it an aesthetic thing or is it about trying to be 'faithful' to what exists in the vastness of what is out there. In other words, do we go with what we see/capture or do we invent colour, tone, scale, star size etc. Astrophotography, at least in the end result, seems more like art than science. You only have to compare images of the same subject from different Astro photographers to see that it is more about interpretation than about reality. BTW I think they are both wonderful images in their own right. I mean, not so many years ago images like this would not have been achievable by Joe public (no disrespect intended) 🙂

Yes Vlaiv, but a little good data is easier to process than lots of not so good data I find. (?)

Yes Tomato, exactly what I am finding. I recently imaged the Wizard Nebula and managed around 10 hrs of data over 3 nights. My first session was just over 3 hours worth, so when I got to 10+hrs I thought there would be dramatic improvement. After throwing out the obvious bad subs with star trails, clouds, cat playing with cables etc. there was still a lot of subs that fell below the 'benchmark' in DSS that I had set from the first batch of images and the temptation is to say, 'sod it' and put everything in the mix regardless (technical term) but I have slowly begun to realise this is self-defeating in terms of final image quality.

You are correct in what you say Vlaiv. The image was just supposed to be a quick example of exactly what you have just outlined so precisely.

I have been pursuing the impossible task of astrophotography for a couple of years now and the penny has just dropped. Namely, that the sheer quantity of data processed does not necessarily equal a good quality final image, rather it is the quality of the data processed. To quote someone who knows more than I do about this subject, 'Put crap in, get crap out!'. Just as a quick example, I imaged Saturn a few days ago with 4" refractor scope (planetary is not usually my thing). Video 5000 frames and then processed in Auotstakkert, Registax. Then tried decreasing the number of frames used for stacking in each image. The processing was exactly the same for each image. Obviously a 4" scope with shortish focal length is only going to capture a limited amount of detail for this subject but hopefully it demonstrates the point. Maybe 1% would be perfect!

30 x 2 minute subs with Altaiar Astro 269c PRO. Is it really dust? 🤨

Amaaaazzzing!!

Hi I've been using one of these for the last few months Gigabyte NUC BRIX i5 PC GB-BXi5-4200 2.6GHz 8GB RAM 128GB SSD WiFi HDMI Warranty | eBay It has solved all my cabling problems and I run an AltairAstro 269c PRO TEC, ZWO mini guide cam and a Exos2 PMC8 from 3 of its 4 USB ports. Worth a look.

The diaganol needs to go and then its a case of getting your camera sensor in the right position in relationship to focal length of scope. Michael's explanation above nails it. You will need relevant camera adaptor and probably spacers.

Wish I could offer something helpful. That's what I like about AP, just one problem after another. So many variables 🤪

Congratulations, good shots. I was using a Canon dslr and found getting the iso down as low as possible (around 200) combined with as many subs as possible was the way to go. Focus assistant in BackYard EOS was also a game changer. Cheers Jack

Thanks for comments and suggestions. Sorry about diffraction spikes Michael, I was trying out some new Photoshop plug- ins. I'm not keen on the spikes in that image but my missus likes them, says it makes them look like 'proper stars'.🤩

Hi I was wondering if anyone else is experiencing the same issues I have with PHD2 guiding. I have been using PHD2 guiding for my imaging for about six months now, so still relatively new to the software. My mount is not high end, it is the Exos2 PMC8 so I know it has it's limitations. Before guiding, anything above 2 minutes was pushing the envelope as far as trailing stars. With PHD2 I can now consistently get, good quality, 5 minute subs. I have had no need, as yet, to push it further. So, all good. Nice round stars, nice images with my 102mm f7 refractor. The stars are round, the images are pleasing... what more could you want? I want a PHD2 display graph that looks nice and smooth rather than the saw toothed, jiggy jaggy mess that it shows me every time I'm imaging. Maybe it's something to do with the sort of person that's drawn to astrophotography? Some sort of OCD? Maybe it's just me? BUT it drives me mad! Why can't it be nice and smooth, or at the very least, stay with in the 1" lines? Mine is all over the place and I have tried everything to improve things, including a complete strip down and re-grease of the mount, and nothing seems to improve the jiggy jaggy bloody graph! And yet, the stars are nice and round and, for my level of equipment, the images are pretty decent. Do I need therapy or just switch the display graph off?

I am such a noob to AP that I thought I was imaging Ghost Nebula (vdb141) . Must have had one vino too many when using C du C. This was around 3hrs worth of 3 minute subs. Hardly any processing, because I don't really know how yet, using Deep Sky Stacker and Photoshop. Shot with Altair Astro 269c tec pro OSC camera, Starwave 102mm, on Exos2 PMC8 mount. I've seen some really incredible images of the Iris Nebula, so I'm not getting too carried away with this attempt...but, it is dusty!

I agree with John, a zoom eyepiece for terrestrial viewing is probably a better way to go than a 4mm eyepiece. Chances are that at 250x magnification, most of the time, air disturbance will degrade the image too much. At least with the zoom you can 'back off' the higher magnification until best image is achieved and push it up if conditions allow.

Shorter eyepiece focal length would seem to be the easiest most cost effective solution.