Jump to content

Stargazers Lounge Uses Cookies

Like most websites, SGL uses cookies in order to deliver a secure, personalised service, to provide social media functions and to analyse our traffic. Continued use of SGL indicates your acceptance of our cookie policy.

sgl_imaging_challenge_banner_30_second_exp_2_winners.thumb.jpg.b5430b40547c40d344fd4493776ab99f.jpg

DaveL59

Members
  • Content Count

    245
  • Joined

  • Last visited

Everything posted by DaveL59

  1. ok after a degree of faffing about, the 1B version is back in the small dome and now the 5MP is fitted up in the old dummy dome, side by side on the edge of the shed roof. Still to fiddle a bit with the settings on the new one but its certainly working old first and new below. The new one is showing more colour esp to the brickwork but I guess the acid test will be night sky assuming its clear enough.
  2. ack so a minor error on my part. New board module arrived, powers up and gives a nice image. BUT its slightly oversize for the mounting sphere in the mini dome... DOH! So I guess plan-B then, leave this one up and re-fix this new one in the dud dummy dome housing to test and then acquire a new dome for its final fit. Got one on order that I purchased cheap as not working, that's of the larger type with an arm to wall mount it, so hopefully won't be a problem So I guess a side-by-side test is on the cards after all lol
  3. yeah I think it may be an insurmountable issue tbh. Thinking back to photography days, losing 1/4 up to 1/2 of a stop is reducing the light entering the sensor plane and in such low light, while you might compensate by increasing exposure time or pushing the ISO (sensitivity) you also gain noise. Also each point of light is now much smaller at the exit pupil (went from FoV 110-180) so per pixel on the sensor there's less light and more dark hitting it, hence you may get brighter stars but not so much the dimer or further stars. I was a little surprised the sky was so dark compared to the 2.8mm lens tho, I'd have expected the background luminescence to have still showed the trees for example. Even switching to CS lenses there's few in the f1.x range and they are mega pricey (350 ish) vs the more available F2.x ones in the £45 bracket. So even with the larger glass you still have the issue of not enough aperture so back to the same situation I expect. In fact the F2.x CS lens isn't that much bigger at the objective than the M12 version, around 30mm so not really much gain for 5x cost. I did have a fiddle with brightness etc and turning on WDR and it lightened things up a little but noise made the image less useful. You could make out a couple stars but pretty much not a very usable image. Still, we'll see with the new board module, one difference with the 5MP sensor that's coming in today is it'll have smaller pixels and similar sensitivity. Not expecting a step back to the earlier setup but it might help a little. Wonder how possible it'd be to hack the on-chip OS to push the shutter speed slower as 1/25 is a lot optimistic for night sky, beyond my skillset tho I'd say, am way too rusty on coding these days and these modules can be easy to brick. Its almost tempting to try a hacked USB webcam, but I doubt the network-USB server would handle streaming video, its fine for scanner and small file transfers but doesn't cope well if you push large sustained transfers at it. Don't really want to put a PC out in the shed as it gets way too warm, plus am not sure about a new neighbour esp after the police have visited several times recently...
  4. ok so while the day view with the new 1.7mm lens was great, the step down from f1.8 to f2 is costly and that loss of light pass means pretty much nothing showing (well, one star low left of centre) where the previous lens showed the tree outlines against the sky as well as some brighter stars, oh well Even the aircraft lights are dimmer than with the faster 2.8mm lens. Will see later how the moon shows but at the mo it does look like a big hurdle, trade off FoV vs faster lens. Also looks like a street light on the far side is reflecting off the lens onto the dome and causing a double "star" pattern, don't think it is the neighbours light in the window but I guess when they turn it off that'll confirm things. A little disappointing then, but of course the stars will be "smaller dots" now that the FoV has expanded so much and that maybe isn't helping either. One option might be to use 2 cameras with 2.8mm lens alongside each other to give a half-half overhead and use a larger dome to house them, hmmmm. Lets see how the 5MP IMX335 starvis+1.7mm plays out then can decide next steps... which could well be tomorrow it seems as its already cleared customs
  5. yep is just the flare on the large front lens element from the sun hitting at a low angle and bouncing internally, looked pretty neat tho, sun setting but outside the actual image area of the lens or was that burning its way thru anodised ally casing to reach the sensor, transparent aluminium is here at last A couple months back I was out for a smoke and there was the crescent moon, but it started as a single at the top and had a double at the bottom. Wasn't able to get a decent pic but I was seriously wondering what was up with my eyes when I first saw it after playing with aligning binos earlier in the day but was the same effect with one or two eyes... @Mars - what's the CS lens you are using tho? I just switched up from 2.8mm to 1.7mm so FoV went fro 100 to 185 degree, tho I'm probably only getting 170 of that since the lens sits just below the edge of the inner module mounting. I did think about going CS for the 5MP module I have coming, for the larger optics, but then there's a jump in price from £7-12 for M12 to £25+ for the equivalent CS and the v small dome case wouldn't have handled the physical size of the CS unit. Oh and they tend to be for larger sensors so hard to get the full view on a smaller 1/2.8 one. Might consider it further down the road if I can sort a housing that would handle it as it'd only be a case of swapping the board lens mount and screwing in the new lens.
  6. ahh looks like the sun has found a way past the edge of the lens as it sets
  7. yeah I figure that's likely, one day... maybe, but for that one task those eyecups would be mega pricey where I only need to knock up a couple. Fashion a mold and the sugru or thermoplastic would be way cheaper hence that's a long-term back-burner one
  8. well one that is parked for now was looking at making a mold to make up new eyecups for some mini binos I have. Lately was thinking hmmm, 3D printing... not that I have one but they're low price nowadays. Not sure how easy it'd be to knock up a design nor how smooth the finish would be on something that's approx 12-20mm diameter and tapered, one day maybe...
  9. ahh I'm the same tho, have a couple binos that I'd like to finish fixing up and also to investigate a bit more on what blew on the electronic control on the miele hoover, that got parked as my eyes got too tired looking at micro surface mount stuff. Have another working one to take comparative readings but sort of lost the will a bit on that one. Did flock the objective tubes on the old hensolt dialyt's I've been restoring the other day tho, wow such an improvement to the image when the sun isn't far off axis and a fantastic £15 purchase, one of my favourites in the collection. Am currently looking at what's best for the wee Tal-M in terms of repaint, downside of spray will be the "mess" as I've not much space to work in, shed's cluttered but likely the best place to work, tho spray paint in enclosed spaces not so good. Might look at getting the metalwork powder coated instead tho. Too many projects but I'll catch them all up, eventually, kept me from going stir crazy in the long work gap
  10. yeah kinda the wrong time of year to start this project but once done it'll be there for a good while. Plus so far am able to spend the time, at least till the new job starts in a couple weeks, then it'll be eves and weekends only. So far when the sky has been reasonably clear its still bright till midnight and of course the moon phase does impact what this camera can see. That said, last night it was still seeing stars even as the moon crossed into the view so might even get better views now with the wider lens fitted. Nice too I can full screen this on the second monitor and almost feel like am out in the open air while at my desk
  11. yep, more sky and in focus too Didn't see the point of tweaking the last setup when I knew the lens would be here a day or so later, figuring the odds that the more often I'm taking it to bits the sooner I'll go drop one of the tiny screws lol
  12. yay so the new lenses arrived The 2.1 needs a longer m12 mount and I just CBA to swap that over from the original TVI unit I removed from the dome, but the 1.7 does with a turn or so to spare, I use a locking ring so it ain't gonna shift focus or fall off. Had to pull the boards from the sphere as the lens is wider than the hole but sits lower than the rim, more fun with tiny screws while up the ladder. Still, its in and hopefully focused reasonably well and back on the shed roof once more. Not a bad super-wide view I think tho not the complete image disc as it clips on the longer sensor edges. That's ok as otherwise it'd be catching the upper windows and more of the tree, tho upside would've been getting some view of the small planes going to/from the local airport. Other limiting factor is that with the lens sitting lower than the lip on the sphere it cuts the Fov slightly by a few degrees, not bad tho. So SkyCam v1b is now up and running, at least for a few days till the 5MP board arrives. Might look at how I can run both the IMX291 & IMX335 cameras alongside each other and be able to directly compare on the same sky views, tho one will be hampered by the dud dummy dome casing. I do think that a M12-1/25-inch nosepiece just might make one of these viable as an eyepiece imager further down the road, via video recording and stacking. IP connectivity not a problem to me in the garden as I can just run a cable out and power it via the LAN cable. Might as well re-use the tech I have sitting around than be buying something else, at least till I decide if this is what I want to do and learn a bit more...
  13. thanks Gina For what is in fact a mini CCTV with a 1/2.7-in sensor and a lens that's 15mm across I wasn't expecting planetarium grade images, tho was hoping there'd be a little more. But then the setup is geared at closer objects and day or IR illuminated use really, with the smarts for H264/5+ encoding and motion detection etc sapping power from processing abilities. I don't seriously expect the 5MP will be a big step improvement either, same issues and although a bigger lens its still tiny compared to the C/CS mount lenses or the fab lens you're using, nor a "proper" camera like my Fuji S100FS. The latter I may try piggy-back on the 130EQ2 at some stage when I want to try some imaging as I do have a timer controller so would be able to do long exposure or video and try the lens set from 28-400mm to see how well it copes, the R/A motor on the mount should help it track reasonably well, maybe. The moon glow has been creeping across the sky here too and now just coming into frame, the sky is full of clouds again, always the way huh.
  14. hmmm so now is dark and clearer, I can see a couple stars, but as little circles not points, so pretty much confirms focus needs tweaking. Oh well, can wait till the new lenses arrive as it'll be fiddly dismantling atop a ladder and opening up the unit in the dark. I can tho make out ursa major and another bright star, and noted a few planes traverse overhead too
  15. sorry to resurrect an old thread but seemed more sensible than starting another Tal-M thread. I bought a 1994 one a short time ago, needs a little refurb but in generally useable condition and in the wood case with wood supports. Initial impressions are that its a lovely little scope and very well built. The white paint has taken a beating and it was missing both OTA end caps and only has the barlow and 15mm eyepiece with the 32mm helical focuser and in-built finder, screwdriver and brush, but no spanner or 25mm EP not the extension tube. So to replace the mirror end cap I ordered a 110mm OD nitrile bearing cap which is a nice snug fit, plus a plastic 110mm tube end cap for the open end, just trimmed the fins off and filed smooth to suit the OTA. A 35mm served to replace a missing foot pad also, just trimmed down the length to suit the shallow foot recess. Hopefully that may come in useful if anyone else needs to source replacements in the future I've also stripped off the thin foam on the wood supports and replaced with felt and found a couple spare bino lens caps to cover the finder objective and 15mm lens. I'm hoping I might eventually source an original 25mm eyepiece but looking at other posts on the TAL-M it seems there was an extension tube also? So perhaps another missing item I hadn't realised I may need, could a standard 1.25-inch short extension tube be used I wonder? I've tried standard 1/25-in eyepieces and ran into the focus issue (not enough in-travel) and I do wonder if part of that may be due to the way the tube is not very deep? Anyway I've moved the primary mirror inward using longer screws for now and can get the newer EP's to focus fine, that is unless I add a filter and then they don't quite, so may have to move the mirror in a little further later on. Also replaced the secondary adjuster screws with longer M2.5 ones that clear the spider, to make future collimation a little easier. Downside is that now I lose the use of the finder scope unless I use the 15mm original EP. Also I find that neither the TAL barlow nor a regular 1/25-in barlow will work for any EP against the main mirror. Am thinking of options regarding the finder, is it possible to shift the objective in further to compensate? But before I start dismantling it all I figured best to ask those more experienced and I noted AndyH mentioned moving the primary on his M and wondered if you found a solution for the finder too? Or do you just use original EP for finder and then switch to standard EP's for observing? I wonder if the later TAL-M's had similar issues with regular EPs or if not how they solved the finder issue, is it possible maybe to replace the helical focuser with another helical with more travel? many thanks Dave
  16. if you take a look at my "el-cheapo sky camera" thread I've listed the one I've ordered
  17. hmm so as the sky is clearing, the focus might not be soo bad as the v high cloud looks reasonably sharp compared to the dark low clouds when I first fitted this version up. Some flare from the sun hitting the lens plus a reflection off the lens onto the dome but there's not a lot that can be done there - not like I can fit a lens hood on a v wide angle lens under the dome after all No doubt the flare and reflection might worsen once the wider 150-180 lenses arrive which may well be later this week as they're in the country already and the 5MP board is imminently departing china on its way here too. Light rain earlier hasn't affected the rig and so far being toasted by the sun its still working fine too. The black dome structure the module fits to is metal so could be a double-edged sword tho, shunting heat away from the module but also getting hot from direct sun and cooking it. hmmm will have to see how that goes over summer as temps rise...
  18. not so far, but then the camera board modules do generate heat and run quite warm, so I guess that'd keep the dome above ambient. Hog cam is exposed direct to atmosphere and never had a problem over winter so hopefully the dome will be the same. Forgot to wipe it over with rain-x when I fitted it so will get around to doing that when I next open it to adjust focus or fit the 5MP board, just to hopefully keep the dome clearer in the rain.
  19. ahh I wondered when the kitties would investigate... I guess the next obstruction will be lookup up a birds behind lol
  20. ok so with the right lens with IRcut filter, doesn't seem too aflicted by the IR lighting thinks the focus will need tweaking tho as I think I've over-reached the infinity focus but wasn't anything useful to fix to with the dull cloudy skies today, but in principle its not too bad. Just missed a bat crossing the camera as I screen grabbed, there's a couple of them that flit around which is nice to see. So now its just a wait for the wider lenses and the 5MP module...
  21. So today the postie brought the new dome camera, wow it was a LOT smaller than I thought but... Stripped it down and its a mini sphere containing the camera unit. Removed the original single-board mini camera module, stripped down the mini-cube and thankfully same board size but mine is a 2.2 board module. But it does all fit with just enough room for the cable connections - I swapped the cable over too since mine is LAN and not AVI. Of course you then realise you shoulda threaded the module end through the base and spring BEFORE closing up the camera sphere... DOH! Once completed, fitted it to the shed roof just below the peak and drilled a 19mm hole into the shed just below the edge of the roof. Oh no! the LAN end won't quite fit grrrr. So stripped the camera down again and fed the module end out from the inside and reassembled it all once again, not fun up a ladder with tiny screws but made life so much simpler. Nice thing is I only need to undo a small allen set screw to unscrew the outer ring and remove the dome so I can get to the camera to tweak focus and angle of view. Plus it should be rain-proof with the o-ring seal around the dome and under the dome edge. So there it is, SkyCam_1a
  22. know what you mean Gina, same here. May well find out how water resistant my el-cheapo is soon lol
  23. hmmm, been looking again at the mk-1 setup and I'm not so sure the filter on the lens really is IRcut, or not effective at least. The tree should be showing green leaves now and they're more purple which makes me think that one had the supposed IR filters I'd ordered separately and fitted but they are only UV. Oh well, too late to mess with it now given its silicone sealed and weather outside is a little damp. One to sort when the better housing arrives and the Mk-1a setup is ready to go... Will be less of an issue with the 5MP unit is that has switchable IRcut, should be possible to force it into colour/B&W or auto as desired too
  24. oh I guess I should add, having tried the Tal 15mm in one of the other scopes, it won't fit the 1.25-inch focuser, so I guess what I'm seeking is the older 25mm eyepiece that is a 32mm fit rather than a regular 1.25 incher, just to make life harder lol
  25. ok so looks like the IMX335 might be good, smaller pixels than the 291 but good sensitivity from what I've found. So decided I'd purchase one and have a play. Pretty good price for the module with a 1.7mm lens supplied
×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.