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JayPea

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About JayPea

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    Hertfordshire
  1. Hi All, I'm overdue with posting these but I was lucky enough to see the blood moon on the last night of our holiday. We were on a site by the beach in South Brittany and although we had rain and clouds that afternoon they parted just enough to see it. I only had a 17-50mm lens on my Nikon D7100 but I did have a bendy legged small tripod I could stick it in the sand with to keep it steady. There were quite a few people milling around the beach waiting for it and we got talking to a Dutch couple also there to photo it. It felt like ages for it to appear but it was interesting to see the planets appearing first. Base on the Stallerium phone app I think we could see Venus, Jupiter and Saturn in addition to the Moon and Mars although they were obviously spread all across the sky. Once a cloud came over we walked back to the site and by then the moon had reappeared between the tree branches and you could see the eclipse slowly moving away. Below photos are: #1 When it first appeared - f2.8 1.6s #2 When Mars appeared - f2.8 2.0s #3 Just before a small but long thin black cloud came in front of it, quite cropped- f2.8 2.0s #4 100% crop of eclipse moving off - f2.5 2.0s #5 Poor camera phone panoramic trying to go from Moon, Mars, Saturn (too faint on this particular image - I sure it was just above the cloud but maybe behind by the time I took it!), Jupiter and Venus. Well worth the waiting for. John
  2. Thanks for the confirmation. The supplier is obviously OK to swap but understandably surprised it could have the Nikon one in the Canon box.
  3. Hi, Just a quick question. I took delivery of a new Geoptik CCD to Canon EOS mount today. But my EOS bayonet mount is too big to fit it. Now I'm 95% sure they have sent me a Nikon version (although it's in a "CCD - Canon Connetion" box). I hesitate as I'm actually going to use it on Nikon G (no aperture ring) lenses so I have a Nikon(G) to Canon EOS adapter with the aperture arm adjuster on it. So it's the EOS adapter that doesn't fit. I'm no Canon expert but I know they have some different mounts unlike Nikon that stuck with F mount. Maybe I have the wrong adapter? but I have no Canon EOS lenses to try on it. I've tried a Nikon lens on it and the fit is a bit lose and it doesn't click into place. It looks like you tighten up a ring to clamp it in place and then it's OK although it doesn't align with the lens white dot at the 12:00 position. Is this expected? I think the other giveaway might be that it only takes 1.25" filter and not 2". Can anyone tell for sure before I ask for a swap? Pictures below. First has Nikon lens cap, Geoptik mount and the Nikon side of the adapter. All are around about 46.7 diameter female bayonet hole. Second shows the Nikon lens clamped on and the back of the Geoptik - only 1.25" filter space so Nikon version? The mount also looks used with marks on the flat face and scratched threads which might explain why it's been out the box and put back in the wrong one. The third just shows a Nikon lens with the adapter on it. I'm estimating it needs a 53mm female bayonet verses the 46.7 I have. Having just written this I'm more like 99% sure it's a Nikon mount but I think I'd better check before I swap. Thanks for your help, John
  4. Unfortunately I don't have a OIII filter . If I was sure it could work well with light pollution I could be tempted. With what little testing I've managed so far the small sensor and pixels (2.9um) have not proved a problem. But I've only used it with f2.8 camera lenses and the BSI nature of the sensor probably helps with the faster glass. I'm finding telescopes generally a bit long and slow for the FoV I think I need for the smaller stuff. I'd like a 300mm focal length f4 telescope if one exists. I'm considering an old Nikon 300/4 ASF prime (can't afford a 300/2.8!) as an alternative. But first I need a way of shoe horning a filter wheel in there and I think that's easier with a telescope than a camera lens.
  5. I finally managed to try out my camera properly last night both with a DIY lens adapter and new DIY peltier cooler. Two of my last three attempts have ended with disappointment with washed out skys. Probably from a combination of excessive light pollution and not the clearest skys by the time I’ve set up (I was desperate to try it!). I’ve had the camera since May and apart from quickly testing it worked when I got it, last night was only the second time I’ve got a proper DSO image off it. Because of security lights, car park lights, street lights, soggy grass and a good view of the moon I was setting up in my north facing front drive rather than the back garden. It’s fine but I must remember to duck my head when I retreat to the garage. The bloody door tried to scalp me last night. I’m glad I had a thick woolly hat on. As well as trying the DIY cooler (well, more of a slight chiller) I was also trying a Hydrogen Alpha filter for the first time. So I chose the Elephant Trunk IC1396 and surrounding nebula. I’d made an adapter to attach the camera to my Nikon lenses (last night using a 70-200 at 70). But now I have the cooler attached I need a lens with a foot for attaching to the mount. Therefore I couldn’t use my little 50mm which looked ideal. So I was expecting the image to not quite fit on the sensor. For once things ran smoothly. I set up in the light and aligned finder scopes with lenses and checked it all worked. I went back out around 7:00 and polar aligned. Luck was with me and I could see both of the first stars through gaps in trees for a 2 star alignment. I don’t think I’ve ever had that before. Focus was a problem though. At 200mm I could see the Bahtinov cross pattern clearly but not when zoomed out to 70mm. So I judged focus by eye without the mask. I then slewed to the target and checked with online plate solving that it was looking at it and all looked OK. My DIY guide scope could see a few stars. I reduced the exposure to get less blobby stars and guiding worked straight away. Some frustration with the focus but otherwise all relatively quick and easy for once. Apart from the bump on my head I don’t think I’ve had such a painless set up. I set the camera (ZWO 290 mono) to 60 seconds and a gain of 300. I’m not sure what the best settings should be as I haven’t had opportunity to experiment. By now the chiller had settled the sensor temperature to around -0.5 degC. I got it going for 35 shots and went inside for drink and telly. I ran a few batches of images off through the evening. Focus didn’t look to move. By the end I was getting the impression that the sky was less clear than when I started. Looking below Polaris it gets quite orange and starless, almost like a haze in the sky and Polaris is only just visible. So by 11:00 I switched to collecting darks and packed up at 12:00 just as the street lights went out. Out of 225 lights I had 3 that showed obvious movement so I ditched them. A stack of the rest and a quick tweak in Lightroom produced the image below. I’m more than happy with that for a Saturday evening. Next plan is to get to grips with a star mask. I’m finding the stars are getting quite big by the time I’ve processed the image (although I guess that might also be focus in this case?). I actually feel like I’m making some progress and Ha mono looks the way to go for my situation. Cheers, John PS doesn't it look more like ET's finger than an elephant truck?
  6. The fan is very quiet and I feel nothing by touch but I guess only testing for real will tell.
  7. Hi, I recently stumbled across a USB fridge (by Satzuma) for the grand price of £7.17 including P&P and it was too tempting not to try it out for DIY sensor cooling. It turned out to be very quick and simple to get it attached to a ZWO camera. Two screws take the fridge case apart and you are left with a nice assembly of the peltier sandwiched between a thin metal plate and the heat sink fan assembly. It also keeps its flying USB lead and switch (cool/off/heat) and a coloured LED to indicate which operation is on. Simply take the metal plate off (remove two screws) to expose the cool side of the peltier. This then leaves two convenient holes to use to clamp the camera to it. I had some old Perspex sheet I cut appropriate holes in and I luckily stumbled across some long screws. I also had a few offcuts of thick heat sink pad to cushion the clamping. I also cut short a screw to fit into the empty tread in the camera centre. For once I didn’t need to buy more bits. I had an suitable old USB charger for power, but I have also used the laptop port OK. It draws a constant 1.0 Amps at 5.0V. Testing today in the garage at 15degC ambient the uncooled sensor temp is around 20degC. With the cooler on it gets to around 5 degC in 30-40 mins and by then cooling appears to be flattening off. I’ve been seeing condensation on the camera body, so I have used some offcuts of a camping mat the insulate the body a bit. There does seem to be a noticeable difference in the dark test images. Below are a couple of 2min exposures at 300 gain to compare. Taken on an old PC so not USB3. Viewing in FITS liberator really shows a difference – I think they are displayed at the same settings, I’m still getting to grips with that SW. Screen captures from Sharpcap also shown. Anyway, can’t complain for £7! Maybe one day if the clouds clear I’ll be able to try it out. Fingers crossed for tonight. John
  8. Craney, the fairy lights are the least of my dark site problems (they have a switch). The three orange street lights may go out at midnight but the bright white old folks car park and security lights stay on all night and then there is next doors extra bright wide angle security light that I set off if I so much as breathe in my back garden. An ex Gotham city police bat light? Makes it easy to set up and take down in the "dark" though :-)
  9. Hi, I had a first go at Saturn last night. I was having a second go (1st go was Jupiter) with my ZWO 290 MM, Nikon x2 teleconverter and my basic StarTravel 120. I was finally set up, focused and (eventually!) had Saturn in my viewfinder by about 10:15. I approximately aligned the tripod but there was still some drift of Saturn in the viewfinder over a couple of minutes so my first trial drifted out of my cropped imaging view within 40 seconds. But all looked to be working OK. So off I went recording. Shortly into the clip Saturn disappeared! I hadn’t appreciated the clouds were now coming in. I tried a few more times but they were never quite as clear as the trial run and so I gave up and came in. I was pleasantly surprised with the result (Autostakkert) from the first clip. I can see the A and B rings although maybe not the dark gap/band inbetween (is that the Cassini division or Huygens gap or called something else?). Something to work to in the future. Below is the result. John
  10. Thanks for the encouraging comments. I went out briefly the following night and tried again with a little colour USB sensor board (3.75um Aptina AR0130 1.3MP). Unfortunately I stripped the thread on the 1.25" mount and it wobbled too much and drooped so that stopped play early. I also had loads of dark spots from sensor dust. Being USB 2 and colour the frame rate was way slower. But I managed a recognisable disc as Jupiter. But no detail as the resolution was lower as the sensor pixels were larger than my mono sensor. Nothing to write home about. Then it struck me I have a L and a RGB image I could blend and give the mono image a boost. So I rotated and enlarged the colour image to match the mono one and used a simple luminance blend layer in Photoshop Elements to combine them (L and RGB blending). Result below with the colour Jupiter I used for RGB. I think the technique has some potential especially if I can get a better colour images at the same time. As I don't have RGB filters or filter wheels it will have to do! So I've been pleasantly surprised by the results, so much so I proudly showed the mother in law. "Very nice, is that the moon?". That reminded me I shouldn't get too carried away with them! I've since fixed the focus droop/slop, stripped threads, cleaned sensor marks and I now know where best to place the scope for a better view. So I'll keep trying. John
  11. Hi, I managed to have a first go at Jupiter on Saturday using the video frame staking method. I have a simple Skywatcher Startravel 120 and I've recently bought a ZWO ASI290 MM uncooled. I can attach it to a Nikon mount through a DIY adapter and using that I attached it to a Nikon x2 teleconverter and then that to the scope giving a total of 1200mm. That gets me ~70 pixels across Jupiter. To start with I was just experimenting to get the thing in focus and recording. The scopes focus has loads of tube play/slop so as you rotate the wheel the image goes out of view top and bottom. Drives you mad and makes fine focus all but impossible on such a magnified image (I've since improved the play a lot). The video image looked poor to me and I wasn't sure it was at optimal focus but it was a test of the connections and set up really. So I ran a 1 min clip anyway. All looked to be working but the videos look a lot worse than I expected. So I dismantled the adapter and put a contrast booster in to start with. I was going run through my filters. Now the image was a blurry smudge, Jupiter had dipped just behind the branches of a tall bush. So getting frustrated I gave up and came in. But to test the process I ran them through AutoStakkert anyway. WOW! out popped a clean Jupiter. Finding it hard to believe the apparent details revealed were real features I checked with the Java Jupiter webpage and got the expected view for that time. The GRS should be bottom right. I then Googled an image in similar orientation (thanks NASA) and compared. I think I can convince myself I've picked up some of the smaller features. I'd be interested to see other peoples before (video frame) and after comparisons. Is my video still typical or should I expect better? I had 6617 frames and found that using anything between 25%-75% produced the best images, lower than that had too much noise. Next steps are to nail the focus and try and get a clearer less noisy video image. Below is a 100 percent crop screen shot of a still frame used and a 100 percent crop of a final stack (a 75% one - only tweaked to increase the contrast a bit. 3 moons are faint). For comparison I scaled down the NASA image and put it side by side. Amazing what detail you can reveal from the stacking. Not what I expected for a quick and dirty test. Makes a change from the usual routine of stacking my DSO images and still not being impressed! John For those interested the camera settings below: [ZWO ASI290MM] Pan=568 Tilt=248 Output Format=SER file Binning=1 Capture Area=800x600 Colour Space=MONO16 Temperature=35.3 High Speed Mode=Off Turbo USB=100(Auto) Flip=None Frame Rate Limit=Maximum Gain=300(Auto) Exposure=0.0016 Timestamp Frames=Off Brightness=1 Gamma=50 Auto Exp Max Gain=300 Auto Exp Max Exp=30 Auto Exp Max Brightness=100 Subtract Dark=None Display Brightness=1 Display Contrast=1 Display Gamma=1
  12. Hi All, One last question before I pull the trigger in an uncooled mono camera (for wide field and DSO, not planets). I've been looking for a quantum efficiency plot for the mono IMX 178 and IMX 290 chips. All I could find was a colour plot for the 290 IMX290 quantum sensitivity but not a thing for the 178. What I also found was a Sony graphic IMX 178 v 290 sensitivity and the following text: IMX290: "Sensitivity @ 533 nm: 6.9 p" and IMX 178 "Sensitivity @ 533 nm: < 3.3 p". So based on the second chart and the text I assume that the 290 pixel is just over twice as sensitive as the 179? That is a significant difference and would probably swing it for me even if it is a smaller and lower MP sensor. Does anyone have links to the QE plots or any experience on these two cameras (I found some interesting ZWO 290 mono images). Thanks, John
  13. Hi, I thought some might be interested in a simple DIY adapter to connect to Nikon AF-S G lenses, in my case to an uncooled ZWO camera. As I’m looking at using my Nikon G lenses but the catch is they don’t have the aperture ring to manually open the aperture when not used on a Nikon camera. I’d seen several people use attachments based around the QSI Nikon adapter with the manual aperture control but at $250/£198 it was bit over my budget. I’d done the usual searches but I couldn’t be sure exactly what bits to buy to guarantee I could just screw on a ZWO to a Nikon G lens and it would work, i.e. the correct spacing and would open the aperture. I already had a cheap (only £5.99 + £1 p&p off Amazon) extension tube set made by Fotga. This was the only one I found with the manual aperture control specifically for a G lens. I also had a few of the 1.25 to T2 adapters spare. So I simply took the Nikon lens mount end from the extension tube set and slipped it over a 1.25 tube using a big doughnut spacer to fill the gap between the diameters and set its length to make the correct back focus required. My final assembly measured 34.4mm depth where I need 34.0 but it appears to focus OK so I haven’t bothered removing 0.4mm. I did cut back the 1.25 tube a bit shorter so I could screw in a filter and still clear the lens mount and it’s all held together with some grub screws. It’s solid when on and easy to remove. It also works well as an adapter for turning the lenses into spotting scopes/telescopes if you slip in an erecting eyepiece. I ordered a replacement Fotga tube set but I got a note back from Fotga saying they’ve sold out and it would not be replenished. But they do a few Nikon G to other mount adapters that look to have the manual aperture control mount you need (I’ve ordered the Nikon to Micro 4/3 adapter, happy to risk it for £8). I think you need the (G) ones, not the (AI) ones. Now my next plan is to actually pull my finger out and get a ZWO camera as I only borrowed one to see if it works! (thanks john78). Cheers, John
  14. After a while dabbling with a dslr and an achromatic refractor I'm after a recommended mono camera and ed refractor pair to upgrade to. I have guiding and an heq5 pro. I'm looking at mono images as I'm in a very light polluted garden. Budget £1300-£1500 for everything (camera, filter wheel, Ha filter, connectors/adaptors, and scope.). Not bothered about RGB initially and I have 1.25 light pollution filters already. I'll be photographing the usual suspects, pinwheel, dumbell, whirlpool, Orion, etc. I assume wider fov would be out for these small chips with most scopes. The zwo 178 mono looks to be my favourite at £375. It looks like it would go well with a 300mm focal length/f4 scope but I can't find one. So the Altair Astro 80ed-r looks good at £600 - top end of budet for scope. Plus a wheel and Ha (75 + 118). I guess a reducer £75, is a 0.6 too much of a hit on the optical quality even on a small chip? Maybe their 72ed-r would be better but I wasn't sure that had a good reputation. Does anyone recommend a proven mono camera/filter/lens combination? I do have loads of Nikon glass but I'm not convinced i can get the mono cameras with a filter attached and meet the back focus so I think I need a scope. Thanks, John
  15. That amp glow at 30 seconds looks more than I expected. Some of the cameras allow 5 to 15 minute exposures. Would that be unusable even if kept down to a few minutes? The only other camera I considered was the cooled 178 (pushing the budget at £700) but I thought you need top class optics for the small 2.4um pixels and obviously with much a smaller pixel area you need much longer exposure (x6?). But then again it's a small sensor so you use the sweet center spot of the lens and you can use smaller filters. Maybe I should just flip a coin to decide...
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