alacant

Hi Could you possibly post a clearer shot? A .jpg covering the whole frame and a -link to- the .cr2 would help us diagnose. Cheers

Hi everyone For our monthly visit to targets suitable for clear skies around full moon, last night we decided upon the double cluster. Also a chance to test the latest GSO Newtonian. It looks like they've upped their game recently. A visitor (A real live visitor. Not seen in these parts since March!) wanted to see if it was possible to guide it, a 203/1000, with a separate guide telescope. It wasn't. Until... ... we remembered @laser_jock99's mirror cell modifications. Next, the dovetail supplied with most big reflectors is totally inadequate, with the obligation to use an OAG. One proper dovetail plate and top rail later and we guided easily for 5 minute frames using a 60mm guide telescope. Unfortunately, with the moon and big aperture, we were limited to 3 minutes, albeit with alarmingly centralised histograms. We managed 27. Would love to hear from other gso owners. This ota at least seems rather nice. Thanks for looking. 700d @ ISO800

The gmic plugin for gimp gives you around 50 different denoise routines to suit all situations. If you can't find a method there, it doesn't exist! HTH

Hi I'm assuming it's a Zeiss 135mm f3.5 (?) in which case at the front of the lens is a 49mm female thread into which the 49mm of the first filter ring will thread. If not, please post the exact specification and/or a photo of the lens so we can recalculate. Cheers

They're only cheap items and it saves you the hassle of blu-tak and glue DIY. For f5.6, the nearest I could get without a longer search, is this and this which gives you an aperture of 28mm; around f5. For exactly 5.6 you need to step down to 24mm. HTH.

Hi Excellent shots. Some of the old lenses are really good. To lose the spikes, leave the lens wide open and use a 49mm to 42mm step down filter ring. There are some good denoising algorithms in modern software. This is the m45 jpg (converted to tif so not ideal) then passing through StarTools' denoise. The latter can also produce excellent synthetic flat and bias for you. Good for when you've forgotten or just can't be bothered! Cheers

JTOL. Processing? Perhaps the easiest image to process is the one with the best/most data, least gradient, taken at new moon etc... Choose any target and get as much data as you can e.g. high in the sky 3 hours either side of the meridian on as many nights as you can. Cheers

Hi The max we have here is 1200mm. Your sct would really make it pop:) Thanks for posting.

Hi everyone No one laugh please. Look carefully and you may just catch it. Cute. 700d on Bresser nt150l

It looks like light is getting into the camera. Is the glow always top right? Have a look at: 1. Block/cover the camera viewfinder. 2. Cover the mirror end of the tube with a black shower cap. 3. Fit a dew shield to the front of the telescope. 4. Examine the tube for places where light could enter, especially around the finder holder bracket. 5. Use ISO 800. I do not recommend taking dark frames with a 650d. HTH

Or simply remove the mirror clips and retain the mirror with three generous helpings of silicone sealant. Eliminates lateral movement too; good collimation at all angles. Cheers

Hi everyone It took me about 10 frames (on each target, DUH!) to realise that at this declination (80º+) it maybe a good idea to turn down guide aggressiveness to almost nothing. In so doing, we reduced fwhm from 4 to 2. Unfortunately, you can't just throw away 10 frames and much as you promise yourself that you'll return to the same target the next day to make up the loss, one we never does do. So, fat blobs and small points:( Thanks for looking and do post if you've had a go at these. 700d @ ISO800 on nt150l 2336 2146

Oh, absolutely 1/10th. In fact the label says, '1/10th. lambda or better...'. But seriously, good luck with the 6" project.

Nonsense. It's extremely fancy. Just zoom on in and feast your eyes on that luxury while lace trim. Invented by Galileo in 1631, the shower cap has been an integral part of all telescopes ever since. Depending upon colour, elasticity and spacing, it magnifies all galaxies by at least a factor of 2.6. Budget SkyWatcher versions still use the traditional galilean plastic pedal bin liner material with the luxury esprit version including a high tech elastic band which guarantees optimum magnification at maximum elasticity. Astro Physics demonstrated their latest platinum trimmed cap via video link at NEAF last month. Current delivery time is three years for the top of the range green version. Highly recommended

Hi Remember that f numbers can be misleading. Loadsa people mistake them. My 150mm f8 collects exactly the same amount of light as a 150mm f2. The only way to get the image faster is to increase the aperture;) Cheers

f8: No corrector required:) The light passes through zero glass on its way to the dslr, thus avoiding multitude of evils! Cheers

Do put a link here if you do. Cheers

Thanks Yeah. There's gotta be someone Perseus way looking back at us. I think the closest galaxy in shot is 250 million light years away. Must be pre-dinosaur even. I wonder if we'll ever get a craft out far enough to be able to take a shot of our galaxy from a distance? So we can see what it really looks like... Cheers

Phew, yeah. Compared to your 1000d, no contest. Especially if your 120 covers full frame, which I think it does. A cooled astro camera anywhere near that size is gonna be €silly. HTH

Hi everyone It doesn't get much more basic than this. Two mirrors in a tube with a shower cap. The galaxies are a bit rough around the edges, but galaxies indeed there seem to be. Colour? They all seem orange. Google eightypercently agrees with this; false colour renditions of galaxies seem not to have caught on. Yet! Thanks for looking. Anyone tried this stuff? 700d on nt150l. ISO800 **EDIT: with Siril's photometric database thingy...

Hi Try to fix what you have first. Familiarity;) The one we use is Siril. This guy did a comparison. Note, Siril has come quite a way since then. It's free and has excellent -almost at the phd2 level, same day- support. HTH

Hi and welcome Great choice. We have the old blue tube version. Really sharp and super fast. You'll love it. Cheers **EDIT: Here are a couple of dslr images taken with our 250p on a rusty old eq6. With modern versions of the same, I'm certain that the OP will surpass this very soon!

These aren't. Nor are these. One set of each will easily get you over the winning line;) Not sure if the asi comes with this. Cheers

Yes. that will do fine. Remember that you also need some distance inside the 72ed so that you can clamp it. After a few year's doing this for any telescope which comes along, you end up with this number of extension tubes, and these are just the ones I've kept tidy. The fewer you have, the more likely you are to fail!

The back focus required for the field flattener to remove field curvature. It is the distance measured from the shoulder of the ff to the camera sensor. No need for websites. It's a 2 minute job! Place the assembly with your extension tubes and adapters -IOW, with the correct ff backfocus- into your 72ed. Attach the camera. Connect to your app of choice so that you can see a video image. Set the focus barrel to about 1/3 of its outward travel. Move the ff assembly in or out until the camera is more or less in focus on a distant object. Clamp the ff assembly using the focuser thumb screws. Now all you need to do is fine tune focus on a bright star. Note the ring stop on my setup to maintain the camera square. If you're not going to use a ff, just measure 420mm from the rear element of the main lens and use extension tubes to hold the camera there. It's going to be the same distance with or without the tsflat2 so the distances in my posts will be the same. A good quetsion to ask would be, 'how long an extension tube do I need to achieve a sensible focus position using my asi183 with a 72ed?' Answer: about 125mm. HTH