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Stefan87

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  1. Thanks so much for the in depth and comprehensive replies! Definitely has given me a lot to consider. That's a shame about that scope Olly! In their description they say it is perfect for Astrophotography but I guess this is another "too good to be true moment". I'm gonna stew on this for a bit and not act too hastily. There have been solid points made about the weight of the HEQ5 and travelling. I'm travelling in a Campervan and have freed up/created more space since my last trip for this specifically. Well, for photography in general. I will prematurely work out some rough weights and make sure I'll still be under before getting too excited. If I may ask another question regarding OAG's? From what I've read, "once you go OAG you never go back" is my take on the opinion of people who have tried both Guide Scopes and OAG. For this reason, and for the sake of getting some decent guiding going right away, would an OAG be the smartest investment into guiding in order to "futureproof" myself in this hobby? Also, Would the ZWO OAG and the ASI120MM Mini be fine to get started with my DSLR as part of the image train on my 6SE? I need 105 mm spacing from my focal reducer, and I feel this should be easily achievable if I place the OAG directly in front of the DSLR. I'm just concerned ZWO have designed their OAG to be used in conjunction with their Imaging camera. This is the cheapest arrangement I can find, and I'm hoping that Mono camera will be perfect but I'm once more concerned this will be another "too good to be true" moment Thanks very much for your help! Stefan
  2. Thanks for the responses. You make a very good point regarding the SCT not being the most suitable for travelling. I'm very close to deciding to sell my 6se and just take the HEQ5 and a new refractor. The trip has been delayed somewhat with the current Covid situation in Australia so I have some time to breathe and get it right. Thanks for the help and thoughts! What do you guys think of this Scope for imaging Nebula/Galaxies? If I purchase a ZWO OAG and an ASI120mm mini, will this be a guiding setup I can use with any configuration? Including the 6se? https://skywatcheraustralia.com.au/product/120-az3-refractor/ Thanks again
  3. Ok that makes alot of sense. But FOV aside, is there a remarkable difference in image quality? Also, does an OAG work well with a refractor? I'm thinking if I purchase an OAG guide setup now and sell my 6se in the future for a refractor I would able to take it with me to use on the refractor.
  4. Hi everyone! I'm new around here and to astronomy and I thought I would share my first lunar attempt! Some of the close up shots you guys are sharing are phenominal! I will make sure I try that soon thanks for sharing
  5. Interesting! I was told that due to mirror shift the Guide scope solution is not entirely practical for the SCT. I'm surprised to here you are getting decent subs out of that arrangement. Are you retaining most of the frames at 180 seconds?
  6. Hey I appreciate your response. Both those scopes are within my budget. I would say 500 pounds would be my upper limit, but I see this as a long term investment so I'm open to stretching the budget. Do you think there is a major diference between the 6SE OTA and the 80ED for AP? I haven't had any problems using the SCT thus far and have been considering selling the Mount and PowerTank to fund an OAG and guide cam.
  7. That clears up alot. And thanks for the link Ian! I glossed over that one previously but never applied the settings as at the time I was between StarTools and Gimp. I will reprocess some data using those settings and see what kind of difference it makes.
  8. Hi guys! I'm currently the owner of a Celestron Nexstar 6SE and have been infected with the Astrophotography bug. It has taken a hold of me and is forcing me to go out and purchase an HEQ5 mount . I have come on here to seek the opinion of more experienced Astronomers regarding my set up. I'm in a somewhat unique position re: upgrading my kit for AP. The reason I originally purchased the 6SE was to use it for visual use for an 8 week road trip through the Australian outback coming up in a few months. The OTA is a fairly compact unit to pack for a trip and it provides a fantastic visual view. Since making this purchase the AP bug has bitten and I have spent a bit of time playing around with short exposure AP using a DSLR on prime focus with the stock mount. Loving it. I'm about to drop the hammer on an HEQ5 to enable longer exposures. The next step from here will naturally be an Autoguiding setup. From what I understand the SCT OTA's are better paired with an OAG for guiding. Is it possible to get a guidescope and camera working well enough for 5 minute exposures on an SCT? I would like to still use this compact OTA with the HEQ5 for my trip but I think I will eventually sell the 6se package to fund a different OTA, thus why I am enquiring about using a guidescope for this set up. I would like to take the guidescope with me to use with my next OTA to save money. Does anybody have any recommendations of another OTA that would be suitable for visual and AP on my trip that is also compact? Thanks for your time Stefan
  9. And it would appear the TIFF does not preview on these forums. I honestly cannot decide which format looks better between the JPG (TOP) and the PNG (bottom) What are your thoughts everyone?
  10. Thanks for sharing the link Happy-Kat! That is exactly what I was referring to. I was maybe a bit too lazy at the time to retrieve it It may be important to clarify for others that have found this thread that this fix will work on many different models of Nikon. Yes Ian it's a long read but well worth it. It seems Mark Shelley is some sort of genius! On another note I thought I would share another process of data that I originally thought I may need to discard after a first attempt in Gimp. Star tools has come to the rescue and provided an image that I'm somewhat happy with. Here is M65 with 40 minutes of 15 second subs at F/10 (1500mm) on a Nexstar 6SE with a Nikon D5300. 20 flat and 20 bias. As you all will most likely know this galaxy is one of the Leo Triplet, but taken at a high focal ratio so a far less impressive capture than what is possible. Definitely not overly pleased with the end result, but at the same time not too disappointed either. I will make sure I revisit this target with my Focal Reducer installed to include it's "siblings". Considering this is a magnitude 10.25 target and I captured it with just 15 second subs, I probably shouldn't complain. One point of discussion I wish to raise is export formats. I do apologise if this has been covered before. I have not read every page of this thread (yet). I have been making the mistake of exporting in JPG!!! I was not aware that if you export with JPG in star tools, it will export as 8-bit. I only became suspicious when I reviewed my post on this thread and the quality and noise in the pictures I posted was so much worse than the final product I remember exporting from StarTools. I did a rather quick process of my M65 stack (~10 minutes work) and exported in what I believe are the only 3 available export formats. JPG(8-bit), TIFF and PNG (both 16-bit???). There is clearly a LARGE difference between the JPG and the TIFF formats. I know this is a rookie error but I thought I would share it anyway in case others are not aware of the importance of avoiding JPG. It appears the TIFF an PNG retain the same level of data. Is this correct? What is everyone's preferred export format? The JPG export is just 41kb. The PNG export is 555kb and the tiff export is 4.1mb. Quite a large difference in file size, but the quality difference between PNG and TIFF did not seem to noticeable on my PC. Especially considering the size difference. M65 TIFF.tiff
  11. Hi everyone! I have signed up to this forum purely to thank everyone on this post who has contributed their knowledge in alt-az astrophotography. Just like the OP and many others in this post, I was told I was wasting my time if I attempt to use my Nexstar 6SE for photography. Until I came across this wonderful post with some incredible contributions and top-shelf human beings helping each other achieve what many people laughed at! So thank you! In particular The Admiral, Happy-Kat, Filroden, Nigel and SteveNikkols. I haven't read anywhere near every single page in this thread so I'm sure I am missing some people and I do apologise for that. I have learnt quite a bit from you guys in particular. Everything I have learnt about AP and Telescopes has been in the past month or two and I know for a fact that my learning process has been expedited by you amazing people. So thanks a million!! I can't imagine how many people you have helped that haven't signed up to say thanks haha It's only fair that I share some of my contributions and knowledge that I've gained. I'm running a Celestron Nexstar 6SE on the stock mount. I only used a Focal Corrector for the Southern Pinwheel Galaxy and I am using a Nikon D5300 as a camera. All taken in Bortle 6 Skies South of Brisbane, Australia. Always stacked with 30 bias and 30 flats. I stopped using Darks thanks to Filroden's fantastic advice, which has saved me MUCH time. First one is Centauras A. This was 48 minutes total exposure using a mix of half 25s and half 30s exposures. Stacked in DSS and processed in Gimp. I attempted to reprocess that stack in Star Tools but side by side, my Gimp effort actually looked better for the galaxy core. Even with the horrible background gradient still there on the Gimp image! The reason being is after performing a firmware update on my Nikon D5300, all my images are displaying a concentric ring pattern. It's a major bug caused by a terrible compression algorithm that only rears it's ugly head at exposure levels associated with AP. There is unfortunately not much of a solution for this from Nikon. When I attempted to "wipe" the pattern in Star Tools, the wipe had to be extremely strong which ultimately made the picture look more noisy and messy than just a simple heavy crop. A top bloke from CloudyNights has developed a piece of software to fix the histogram damage caused by lossy compression on Nikon Cameras but I'm yet to try it. I will be doing this today most likely as I'm off work. Happy to share the link to the app if required. For anyone else reading this that is using Gimp to process their stacks; I followed this Tutorial to learn Star Mask, Background Mask, Galaxy Masking and of course basic stretching. I found these masking steps CRUCIAL in Gimp to the stretching process and getting the most out of the data to produce a commendable final product. But really, there is no comparison to purpose built Astrophotography processing software. Next Image is the Southern Pinwheel Galaxy. This was around 1 hour of total integrated exposure time. I think around 170 x 15 second subs grouped with around 30 x 30 second subs (This is from memory, so not entirely accurate sorry.) I decided to use shorter subs for the main group stack as I was struggling to retain data on my previous attempts due to tracking errors. It was very annoying. I set up to capture 30 second subs for 1 hour as I have seen (I think on this thread??) somebody share a combined stack and they had a much better signal when combing just a few longer exposures with a bunch of shorter exposures. I feel this has worked in my example. This session was particularly frustrating for me as I could only retain 1 hour of data from a 4 hour attempt using a focal reducer AND stupidly short subs!!! There was no wind and I have done everything I can to ensure mount stability. I even purchased "Astrophotophraphy on the Go" as recommeded by Ian and followed his steps to get he most out of my mount to no avail. I was tracking this target due west from around 60 degree altitude until it left site at around 20-30 degrees altitude. Although I'm happy with the result, the lost time due to discarded subs has completely negated the time saved by not needing to set up an EQ mount IMO. I've made a few attempts at processing this stack and processing this in Star Tools REALLY helped me pull much more signal from the tails of the galaxy compared to Gimp. I was using the Colour select Tool in gimp to create my galaxy mask previously and because the tails were so faint it did not work as well as Star Tools for retaining the extremely faint signal. The final image of the Sombrero Galaxy was made from 20x40 second stacks for 13 minutes total integrated exposure time. I unfortunately had to throw out the majority of the stacks in this attempt. I kept 13 minutes from over 2 hours attempting to capture. There are two tables I use to roughly calculate Maximum exposure time before field rotation becomes an issue. They both have different calculations but 40 seconds was well within both tables calculations. It seems that the reason I have so much trouble retaining data is due to tracking errors, not field rotation. It most certainly is not from wind where I live. I actually tried Sombrero before attempting the Southern Pinwheel and that experience Is why I decided to go for 15 second subs using the focal reducer for the Pinwheel. Alas, I still had to discard 70% of my subs In saying that I also tried processing the Sombrero stack in both Gimp and Star Tools and just like the Southern Pinwheel Galaxy, Star Tools really did a fantastic job at preserving the faint signal while not displaying as much background noise. The difference was chalk and cheese. Consdering how low my SNR was due to low total integrated exposure time, I think the final product has exceeded my expectations. Thanks again guys! I more than welcome any constructive criticism! I have a bit more data sitting here to process that I will surely share!
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