Jump to content

740427863_Terminatorchallenge.jpg.2f4cb93182b2ce715fac5aa75b0503c8.jpg

LouisJB

Members
  • Posts

    466
  • Joined

  • Last visited

Everything posted by LouisJB

  1. I can recommend the guys at TS in Germany, that's where I got my GSO 200 from and they were really helpful and the price excellent. There is a 150 GSO F5 which also looks nice, with a dual speed focuser, not sure what mount options that could come with. I think for astro you're going to be too limited on two fronts. One, while the tube is probably great, the focuser is a single speed and doesn't look like a 2" draw-tube, which means things like coma correctors won't fit (and it may not give enough back-focus if photography wasn't in the design). Two, the mount, too wobbly for putting a camera on, although you could dabble at planets and add an RA motor it will never be sturdy enough for proper work. Tube wise, an F5 of that style with a 2" crayford would set you up nicely. However when it comes to mounts there is no cheap way really. You might get something out of an EQ5 but ideally you want HEQ5 pro or better.
  2. universe is believed to be expanding at an accelerating rate, this is not a new finding though, well it's a few years old now. peculiar velocity - is exactly the right term for motion against the general fabric of space although we measure and interpret movement with speed, measuring the velocity of a distant galaxy (via red-shift) will combine the measurement of two properties. One is the peculiar motion, it's velocity against the backdrop of space (whatever that is) and the other isn't really velocity, it's actually a measure of the relative change in scale-factors between now and then (then being when the photons were emitted). Also, there is no expansion in a gravitational bound system, like a star cluster, galaxy, galaxy cluster. Even more so in the tightly bound chemicals of our bodies and the Sun and planets, these forces are much stronger than the Hubble flow that is causing the general size of the universe to expand (at an accelerating rate).
  3. nice work, that's dedication! It's a lovely sight, I'm hoping in a couple of months to point the scope and camera at it and your work reminds me I must do so.
  4. having gone from a single speed focuser on the 130P to a GSO dual crayford on the GSO200 F5 I can say if you're using it to image that little extra cost is well worth it. Tweaking for perfect focuser on the 10:1 wheel is so much more accurate and since it requires virually no turning force it doesn't disturb the rig and live view doesn't blur, so you get a better chance to see what is going on. Having said that you can certainly get by without, just a recommendation from me that the extra $$ is money well spent as it's quite a fundamental part of the OTA. As for HEQ5 - highly recommended by me, I love it. Especially as this opens the doors to guiding. I'd say the synscan pro goto is excellent, but you can save $$ by getting the syntrek and using EQMOD, this would be entry level for a decent guiding ability in the future.
  5. Ok. It's much easier to get good shots of the Moon as it's so bright. Also planets don't require guiding or even tracking to get a picture of, just a way to video them for a minute or two. Even the Sun (with suitable filter!) can be imaged to show sunspots. It's the DSO astrophotography where it get's more difficult, complex and expensive. So maybe a 130PDS on a mount with RA motor (EQ3.2 or EQ5) might do the trick - not exactly sure how much they go for, you could keep an eye on second hand bargains. Focal length is a bit short for planets but you could probably do something with it. Would be great on the Moon. What camera do you have. You might want allow for the usual accessories also, but other than a T adapter I'm not sure many things will be essential to image the Moon and easier targets. For planets you're probably want to use a barlow lens too, as they are _small_!
  6. +1 for Dob, biggest bang for the buck without a doubt. Also, some shrewd searching and maybe you could fine a used 10" for real light grasp Skywatcher Skyliners always seem to get a good review and will be excellent for planets with their longer focal lengths.
  7. nice one, looking forward to attempting this one myself. Can I ask, did you have to wait until the early hours for it to rise up away from the horizon? Also what focal length was that done at? keep up the good work.
  8. It might be visible in bins soon, weather and skies permitting. Although where I am seeing M82 in bins is a challenge, but I have spotted it with M81 on a better night. Closest supernova in 40 years, may last 2weeks, make the most of it!
  9. Hi, I've a couple of unrelated questions. 1. Imaging planets, say Jupiter, I'd like to try something stronger than the kit SW 2x barlow to get a better image scale. What do people use, a 3x or 5x? I'm thinking or jumping to a 5x, is that a good or bad idea. Anyone got any recommendations on either that don't cost a fortune? 2. I guide through ST80, what exactly do I need to order to eliminate the diagonal in the light path to allow my QHY5L-II camera to focus. Has it a name, what length should it be, 50mm? Many thanks!
  10. Hi, thanks. Yes, well I've had guiding working, so I must have done that or something like it (can't exactly remember) - but I think as I didn't need to use ASCOM I avoided it at the time. I don't generally plug into the controller unless I need to use stellarium to move the mount, which isn't really necessary for me in practice and just adds extra wires from the laptop, So many options, guiding can be a black art - still I was getting good results, other than the effects of a larger tube (another +4kg) I hope it will work just fine again. cheers, Louis
  11. Ahh right, I think I'm not using ASCOM at all, I downloaded a beta version of PHD that supports QHY5L-II direct, maybe that's in the main version now, I'll have to look for updates. I've had guiding working for 6mins +, but that was with the little 130P, so it remains to see how tolerant it is with the bigger tube and with the longer focal length... I also use stellarium to control the pointing (via USB->serial->handset socket) but tend to use the handset when outside as the mount is goto anyway. The menu is in the HEQ5 pro settings menu, think it controls the sensitivity of the guiding port, perhaps if you're not used the st-4 port you never noticed or needed it - possibly that's what all your ASCOM settings do instead. So I think our setups are slightly different in that I'm not using ASCOM at all, but anyway that shouldn't matter much to guiding itself. Think what I really need is a good clear night. I'm also much into DSOs and I've been taking some long subs on various targets. But since it was either full Moon and / or cloudy lately I tried video stacking of Jupiter and also better shots of the Moon most recently. The supernova in M82 got me targeting DSOs again, now I have the better tube and a coma corrector the weather really has decided not to play along yet. I only got the GSO 200mm at Christmas and not had clear nights to try it properly, as with anything new, always a new learning curve to work out it's characteristics. So far the HEQ5 has been handling it just fine though, which is a good sign. Hopefully one clear night an hour of experimentation I'll have it sussed again and it will be working like it was on the 130, fingers crossed. thanks for the help.
  12. it's gained a name and Wikipedia entry now http://en.wikipedia.org/wiki/SN_2014J
  13. @Louise Awesome, thanks a lot for that. I'd be interested in your defaults on the HEQ5 pro, I think it's in the 'settings' menu -> 'guiding' (or maybe it's called tracking) and mine is 0.5x by default, but as I mention I've been changing it every time to 1x. What are you using be default? I've never seem that EQMOD ASCOM page, am I even using ASCOM (I'm so clueless I'm not actually sure) - I just have QHY5L-II guiding port connected direct to HEQ5 ST-4 guider port. Thanks for the PHD settings, very useful, I'll check what I have and try adjusting any params that are different if it's not working well. I totally agree, if it ain't broke don't fix it. BTW, I fitted my ST80 on-top of 200 (and 130) for just a few pounds. Price of a dovetail the same length as the lower one you're using. Drill two holes in it. Fit the ST80 rings to the bar by bolting from the underside of the bar into the rings. Then fit the bar on-top the 200 rings with standard bolts. I can get a pic if it helps, bolt sizes were odd but IIRC 1/4 whitworth and M5 are the two sizes in use there (with skywatcher stuff anyway). It's not adjustable, but thats really a good thing as it's solid, rigid, so no flex etc Also I've found it always picks up several stars to guide on, so I've never needed to adjust where it is looking (to-date anyway) @Pat thanks for the link. I always do do a decent polar alignment through the polarscope, enough so as I found out last night that I can get 45s with no guiding and no trails. I know you can get much better, but I think that is then accurate enough to then auto-guide with, without loads of problems due to overcorrection.
  14. BTW, should the HEQ5 default to guiding rate 0.5x? Seems like I'd prefer it at 1x and control the aggressiveness from PHD, how do you go about this combination?
  15. thanks for all the advice. Good to know that fundamentally nothing needs to change. I realise my HEQ5 pro defaults to guiding rate x0.5 and previously I've remembered to bump that to 1x before guiding. Last night in a rush I forgot (also forgot to connect guider cable up first, so that didn't work too well!). In the past I've been able to guide through clouds, but last night thick ones came over and all was lost, during calibration, so it's not really very definitive. Think I need to try it out again on a clear night. Used to guide really nicely with the 130P, I know the 200 is bigger etc but I hope it will guide well enough still using that. Louise, as you've been using the QHY5L-II (is sensitive isn't it, it images M81 and M82 in PHD when guiding in that area!) - can I ask, have you tried it at full res video for planets? I can get mine to produce about say 20fps at 800x600, as soon as I try to go higher it seems to die with 0 frames and maybe lock up such that I have to restart it. have you tried it like this and experienced issues or it working? I blame drivers, but it might also be the mac/VM combination. I'll try on a different laptop sometime, maybe it will work if I upgrade to a new macbook pro - like I need a good excuse!
  16. Only this, which I took to really to see the new supernova in M82. It was a stack of about 9 x 40s, at maybe ISO1600 I think. All I did was a quick polar align, no guiding or anything more. Subs then through DSS and tweaked levels in PS. I think to image this nicely you'd really want 20 or more 5 min exposures etc, but just as I got guiding working the clouds appeared for good, game over! So, this might give you an example anyway for what you might end up with using M82 as a target and unguided short-subs. On a DSLR at 1000mm FL tube M82 is quite small, hence it can be a bit pixellated when blown up. It's a trade-off though, trying to get alignment or guide a much longer FL tube is going to be increasingly difficult and eat into your max sub time.
  17. I did some shots of the supernova in M82 last night, due to having minutes before clouds came along I did them unguided. I pushed it up to 45s (using a 1000mm focal length 200mm tube) and it seemed ok. I pushed the ISO up, even saw M82 quite visibly with a 10s exposure at much higher ISO. Not all cameras are equal though for noise, some much better than others - you'll need to find a good compromise which depends how many subs you can get etc. I'd start around ISO 800-1600 and about 30-40s and get say at least 10 good subs, stack them and process the result - see what you can get. For my best M42 I took about 10 x 3-4min subs and that really starts to bring out all the detail, but then you really need guiding - or you could try drift alignment, but it's going to be a challenge and time consuming! I'm not that skilled so never tried it myself, it sounds difficult.
  18. Have a look for coma correctors, it's basically a lens - between camera and telescope, to cure coma which is what causes elongated stars towards the edges of the image. I tried mine for the first time last night - definitely helps. If blurred stars are only away from the centre and they are sharp in the middle your alignment is good enough for your exposure length and the corrector will cure the rest. You should be able to crank up the ISO, take a bunch of images and stack - but how high you want to go depends how good your camera is at noise. The other thing, I think (I'm learning too) you can crank up the exposure to the point of some light pollution being captured, don't worry about that - as it can be corrected when you process the RGB levels and curves. Good luck. It's very addictive (aka expensive) once you get started...
  19. haha well if it might make you feel better. I spent a while last night wondering why PHD wouldn't calibrate the guiding and would just fail after a long time. - then realised, it helps if you connect the guider port to the guider interface, dah! At exactly that time the clouds rolled over. What a dork
  20. Hi, Just wondering. So I've had guiding working when using the little 130P and it's been great. The guiding is through an ST80, the mount is an HEQ5 pro. I've not had a chance to try with the 200, but tonight I got as far as starting calibration at least before having to give up as clouds came over and it lost the star and was reporting poor signal, but it also said calibration failed, disabling dec. Maybe this was due largely to the clouds, but my question is really, should I be using different settings between the scopes. If so, how would I know what I should change? Or doesn't it matter, since the guider scope, guider camera and mount are the same as before.
  21. Hi Steve and welcome from another stargazer from Sussex.
  22. Here it is, well I hope this is it in the image. Had 20 mins before clouds rolled over, no time to get guiding working so this is a short 40s capture after polar alignment, hence poor quality.
  23. I've seen it! This is a first for me, must dash back out, excited and trying to get an image of it...
  24. Happy days, it's certainly a beautiful universe we live in...
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. By using this site, you agree to our Terms of Use.