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  2. Hi there - Yoddha has been super helpful in addressing any problems I have had with APT...he helped me with the Platesolve2 approach I've settled on...I haven't really felt the need to go to blind solving yet.
  3. There is a submenu "maintenance" where there is an option to make a bad pixel map, but haven't used it this past year. I'll check it this weekend and report back.
  4. I think that it also depends on type of glass. I know that fast triplets need field flattening and have rather curved field?
  5. I just loaded files in ImageJ and did statistics on them. Initially I downloaded only first bias file. It became apparent that something is off when I looked at the stats - it said that minimum value in frame is 0 while median was quite high - at 70. In my experience such high gain should not produce 0 values. This points to a dead pixel or something like that - single value that is set at 0. So I took the histogram to see what it looks like and when examining histogram I noticed that very large number of pixels had 0 value - that kind of surprised me. So I started to examine image in close up trying to see if I can find any offending 0 valued pixels - and while I was doing that I noticed that top part of image is black and uniform - first three pixel rows. They all had 0 value. Later when I downloaded other bias files and looked at the top of the image - I noticed that they all have 1120 values in first row (not first three rows). Idea about usb memory stick being faulty (I'm not sure it is likely in this case) came from earlier. I exchanged quite a bit of PMs with Rodd about his setup and optimum sampling / workflow. He also attached some of his raw stacks and single subs and they had lines with 0 valued pixels in them - however in his case those were not full rows nor were they top rows - they were rather random, but were easy to spot since they were at light frames which have dynamics and higher background because of LP levels. We concluded that it was faulty USB stick because he did not have those artifacts on his work laptop but used usb stick to transfer files to computer connected to internet. When I say that it might cause you trouble - this is what I mean, for example when you align such frames and you stack them you will have pronounced stacking edge artifacts on one side that may puzzle you. Or when you are trying to do statistics on pixel values - stats will be thrown off by same values in one row, and such. Best way to deal with this if you indeed find it is related to camera is to crop your frames - just remove offending top 3 pixel rows or as many as needed. On a separate note, thing that you mention that bias frames have higher mean value than darks is known thing for this sensor, and one of the reasons why bias should not be used. I think that if you increase duration of your "bias" at some point it will start acting normally. Might be that it is related to the way how sub duration is measured. I remember reading that up to 1s exposures camera firmware is responsible for keeping time. Subs longer than 1s work in sort of "bulb" mode - computer tells camera to start exposure and then signals when exposure should end and reads off result. It might be that those two different timing mechanisms result in different offset values or something.
  6. I think you are mixing two things here - rational number and the way that rational number is "produced". Rational number is a number, and it is produced by division of two numbers - specifically for rational number to be a number you need to divide whole number with a natural number (this definition avoids division by 0). Density is ratio - it is "produced" in the same way as rational number, and for most part it is in fact rational number because of this. However there is no restriction on what should go into division here. You can divide infinity and divide with infinity. Imagine infinite number line and finite number of elements on it. What is density of these finite elements? It is 0. How is it 0? Because ratio of finite number and infinite number is 0. Now imagine opposite - finite line segment and infinite number of elements within that line segment - like 0-1 line segment and real numbers on it. Here we have infinity / 1 = infinity. Density is here infinite and it's not rational number. I'd like to point out, with risk of it sounding that I'm again trying to put discussion back in certain direction, which I'm not - is that my conclusions stem from exactly what you pointed out - infinite spatial extent. This and basic assumption of cosmology - homogeneity, and the fact that we observe finite density in our observable patch indeed leads to those things that I mentioned.
  7. Martin, I was wondering if you had any thoughts on whether utilizing NINA as the capture engine for Jocular would be a possibility. As NINA is open source and they support a lot of cameras, I thought this could have some potential benefits perhaps. However, I believe it is Windows only.
  8. Interesting, This is the F8 and I can only for what ever reason believe this must weight more because an F10 for sure does not, I actually looked long and hard to find the weight of the F10 as I was going to de-fork mine to try it on my AZ EQ 6. If this is the same weight and I am stronger than I thought then there isn't much chance of using it on the mount. I am fairly sure I read the 10 inch Meade F10 is 13KG and the Celestron 14 inch is 20kg, I would find it hard to believe the 12 inch is 25kg, if you see my point. Guess the acid test is to stop typing and go outside and take it of the fork and weigh it. Thanks for the link though. Alan
  9. Today
  10. How we perceive the world is indeed very complex and in some cases quite anomalous to the norm as your experience confirms. This is why I teased @saac about what is real. Our perception may all differ to a more or less significant degree and what we naturally take as real might be quite different if evolution had equipped us differently. All the worlds a concept and we are just avatars of a boltzmann brain . Regards Andrew
  11. Yeah currently looking... I have my eye on another SONY VAIO... but if that falls through, I'm considered by a small desktop in the obsy protected from the moisture and rain being located under a permanent roof. Convert the dead laptops LCD screens to a wall mounted dual spanned monitor and VNC into it as necessary instead of carryover by the laptop inside...
  12. hi all, having a clear out of gear i no longer use 1. televue 45 degree diagonal £30 inc p&p 2. skywatcher eq5 tripod with extension £80 collection or meet up. 3. skywatcher 130pds £90 collection or meet up. 4. skywatcher 127 mak £95 collection or meet up. any questions please ask regards john.
  13. Very nice! I enjoyed your report very much and find inspiration to continue trying for more hidden treasures as the opportunity presents itself.
  14. I'm regrettably selling my Canon 135mm f2.0 prime lens as I'am not currently using it very much. The optics are mint with no scratches or chips and I cannot see any dust within the internals, the exterior of the lens also looks unmarked, the only signs of use are some rub marks on the lens hood which was always on when in use. I have had it since new and it has all its original box an unopened leather lens bag, books, paperwork even the original polythene bags and of course lens caps. This lens is absolutely stunning for portraits as the bokeh (background blur) is just creamy smooth with beautiful contrast, its also tack sharp at f2.0 and of course is a great astro lens. check out this dedicated flickr page - https://www.flickr.com/groups/625952@N23/ Buyers are welcome to try out first if face to face, no low ball offers please, also for sale elsewhere. £475.00 with special delivery included.
  15. My Maksutov has never needed collimation, ever. Apparently Maksutovs used to be used for gunsights in tanks. If that usage did not put them out of collimation, nothing will.
  16. I think the general rule is a refractor has a curvature radius of 1/3 of the focal length. So a 1000mm FL frac has a curvature radius of about 330mm, compared to a 1000mm FL newt, which has a curvature radius of about 1000mm.
  17. I think the first thing to do is to try the eyepieces that you have and see if you enjoy using the refractor visually. Given your skies, star clusters and fields will probably be the main DSO targets and I would think that you will want to use eyepieces <18mm to keep the background sky relatively dark. However, a 24mm 68° eyepiece will still be useful as a finder with the maximum field a 1.25" eyepiece can show.
  18. There will be a retaining ring on the underside of the filter, just tighten it up.
  19. Well, I've put the camera into a freezer on the lowest setting, and with the camera on / cooler off, it was reporting -0.5 temperature after stabilising for around 3 hours, so I was happy to proceed. I ran continuous 30 minute darks overnight (at -20 sensor temperature) but last night, I checked the 1st one before bed and the banding seems to be there, faint but noticeable when autostretched - and I know it's not an illusion, as I asked for a 2nd opinion and it was confirmed, as she didn't know what I could see beforehand. I'll stack 50 or so darks later tonight and post the result, but I think I have the same issue and hopefully, all being well, the FW update will fix it.
  20. Hi everyone. For anyone that uses a Meade based telescope with ASCOM, I'm sure that you are all aware that the "Meade LX200 Classic and Autostar #494, #495, and #497 (combined telescope/focuser, 5.0.4)" driver is the one to use. However, it's old and you can only connect one piece of equipment at a time oh and certain programs like WIFI Scope, Sharpcap, Sequence generator pro all have their functionality limited because the driver doesn't implement everything. Well, I started writing a little program that would allow me to set the date, time, site lat and long using a GPS connected to my PC. That way both the PC and Autostar are in sync. However, it turned out that the aforementioned driver doesn't implement the ability to set the date and time, and I think it does something funky with the site too. (Can't remember to be honest, but I know I don't trust it. My solution, I'm in the process of creating a new driver for the Meade AutoStar #497 and AudioStar. Here's the link to the Wiki. https://bitbucket.org/cjdskunkworks/meadeautostar497/wiki/Home I was wondering what sort of interest there would be for my fellow Meade users to get some much better support for our scopes.
  21. I cant remember specifics but my door number was not pleasant, a sort of burnt plastic/cucumber combination. I dont however recall this odd effect in reverse i.e. smells producing numbers. I did look around on the net and this type of cross sensor anomalies is not uncommon in stroke victims and did make me wonder if our concept of Maths and numbers is actually hard wired into our brains. This might explain why the concepts of zero and infinity cause problems and why we struggle with using alternative reasoning to view the world. Alan
  22. Saxon is usually a re-branding of Skywatcher / Synta made products. In this case I think the Saxon Cielo HD eyepieces are a re-branding of the Celestron X-Cel LX eyepieces so look for comments on the performance of the Celestron versions (which are quite popular on here) to get an idea of performance. Celestron is another brand owned by Synta these days. Having tried a few of the X-Cel XL's I think they are decent eyepieces but quite not as good performers as the Delos or, with the exception of the wider field of view, the Vixen SLV's.
  23. Hello Stargazers! I have a 60mm f/6 refractor from TS Optics, which I use for imaging. I really like this scope, and given its small size, I'd love to use it for observing as well. But I don't really have any experience in this field, so I have a couple questions: What kind of target could I expect to see with this kind of scope (I live in a Bortle 6/7 area) ? What kind of eyepiece would you recommend for this kind of scope? FYI, I already own 2 cheap 1.25" Plössl (10mm and 25mm), that I got with my 4" Maksutov telescope. I have to admit that I haven't really tried them with the 60mm refractor yet. Thanks for your input!
  24. Since you have the kit, I see no major issue using a 3x barlow with the MN190 to start with. Yes, more aperture can give you better resolution, but I spent several years enjoying planetary imaging with a 127 Mak before getting my C9.25 and perhaps not having to swap scopes around would be quite convenient. James
  25. Its funny you mention this but for quite a few weeks after my stroke (I am fine now) I could smell numbers and it was very distinctive, looking at a digital clock at 7.30 am was an especially nice smell. Alan
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