alacant

Hi I see 102ed listed amongst your stuff. Far more desirable than the cheap gso we used! I'd guess you'd get a slightly wider field of view, but still easily within reach; 7331 is quite bright. Must be worth a go. Cheers

Hi Lovely shot. You'll notice the superiority of the 60d immediately; the 18mp sensor with its d4 firmware produces far cleaner images. Neither camera however will last long at 1800 frames per session, so it's a +1 from us for a tracking mount to enable fewer but longer frames. Lenses. Along with the 75-300, the 18-55 is not perhaps amongst the better lenses Canon have produced. Your idea of a fixed lens is a good one. If you're any good at online auction, an old Asahi or Zeiss 135 can be had for under €50. HTH

Hi everyone As the moon set, it gave way to darkness. The sort where you lose the constellation marker stars, understand why m39 could be mistaken for a comet and wish your turn with the binoculars would come around sooner. When it does, you convince yourself you've seen 7331; it must be because that's roughly where the telescope is aiming. You then get a WhatsApp message and immediately un-dilate your pupils. Fantasy over. Maybe there's a night vision setting app... So apart from the -I'll-get-there-one-day- processing, no excuses with this. Thanks for looking and do please post your DSLR versions of this region. 700d + gso203 calibración siril 1.1.0 git. revelado st 1.8.525-2 ~4h @ ISO800

Hi Nice shot. Our guess is that some de-noise was applied. Your idea of adding more frames is a good one. Cheers

Yes. That's it. Most old camera lenses benefit from this 'compromise' focusing. Your observations also explain why you can't use a focusing mask. Focus until the red halo just disappears. With the emphasis on just. No need for blue halos. If you want to fix it completely, you'll need a new front element and/or try adjusting the other two elements. Details of dismantling here; make certain that the seat for the front element AND its retaining ring are perfectly clean and even. Place the latter on a non-yeilding flat surface e.g. glass and make sure it sits perfectly flush. But I think you'll be OK as you are. You could always stop to f6 if you still find it's annoying. Cheers

Assuming you have removed all the cross-head screws retaining the mirror cell (!), then probably because you still have the tube rings attached. These distort the tube. HTH

Ah, OK. Yes, indeed. I should have mentioned. Sorry. You need one of these. No idea in English. Is this a lens spanner?

Hi You were unlucky as your Tair has astigmatism. As related previously, this is probably just a case of the front element being distorted by too tight a retaining ring. Loosen, then in a vertical posición, shake to re-seat the glass. Next, re-tighten until the glass just stops rattling when agitated. With this adjustment, and your 72 to 58 step down ring, it should all but disappear at focus. If still intrusive, try 72 to 55; still affording a respectable f5.5. Otherwise and as Tairs are quite common, they rarely reach their reserve price at (on-line) auction, so another alternative would be to just get another:) Cheers and HTH

Hi Mmm. Hotshoe mounted guide camera so, as you can see, a large amount of flex. Try something like this. HTH

Hi Turn the hex key 90º and give it a sharp tap. The whole central secondary assembly will now be loose. To adjust the tilt, loosen ONE at a time tightening ONE other to take the slack. If you're using this for imaging, use a Cheshire sight tube with cross hairs to get it perfect. To give yourself a fighting chance and retain your hair, replace the sw grubs with m4 screws. 10 for €1: HTH

H everyone Despite new moon and with most of the tourists now on their way home, we have the place back to ourselves and a choice of telescopes. Our pn208 had taken a bashing over the summer, but responded well to a heavy dose of cleaning and adjusting. This was started after the haze lifted with the HA at around -4h and I noticed the last few frames were flipped, so probably around 4h total. One is a process of the stacked data. The other is HOO. For 4h and f3.9, disappointing. I thought ther'd be more detail. Maybe this target is more suited to one of the narrower pass filters? Dunno. Thanks for looking and DSLR users, do please relate your findings on this target. 700d +UHC en pn208 ISO800 revelado: siril 1.1.0 startools 1.8.525

Hi Try the 180° first. Although we'd recommend aligning and collimating properly, to do what you want without doing so, locate the three pairs of push-pull screws at 120°around the base of the focuser. Use those to align the focuser. Cheers

I don't think you'll need dither with a 571.

If you're going with the OAG, neither are needed. To help diagnose issues such as these and to give your software a fighting chance, the mount has to be better than perfect. Out of the box, we've yet to see a correctly adjusted, internally clean and correctly lubricated sw mount. An hour or so spent dismantling and adjusting would serve to lower any frustration to a minimum. There are many guides on disassembly and adjustment. Cheers and HTH

Hi No, but there's a bin2 routine in firmware which gives significantly more sensitivity.. If that's what you're after. Cheers and HTH

You'll always get some astigmatism in the corners over aps-c with the Baader mpcc anyway and the corner elongation should respond in going to ~60mm spacing. Apart from the points above, the new m27 stars look fine to me. Guiding at 1000mm is never going to be easy and you'll need nights of very good seeing to be able to do it justice. For other nights, maybe invest in something like a 130pds? Oh and a GPU cc;) Cheers and HTH

Most of the errors with the silicone are caused by pushing the mirror back into the cell instead of leaving it to cure under gravity. You need at least a 2mm thickness to allow for thermal expansion and contraction. Try reseating the primary. If not, next you'll need a secondary of known performance. HTH

Hi All the three frames display astigmatism. We need a shot without a filter to eliminate the same, although I doubt they're the cause. Next would be a shot without the cc. Then substitute the secondary. Then remove the mirror clips... etc. Or simply leave it as it is and correct in software. Cheers

So it's not the cc then;) Do you have an L frame without filter?

Hi There's quite pronounced astigmatism across the whole field. I'm guessing the Baader cc and/or filters. Could this have fooled the focuser? Cheers

Hi m27 shows triangular stars and there is constant elongation in your star tests. Our bet is that the 1º mirror is distorted. Either the sealant isn't thick enough or it has hardened, preventing the movement of the glass as the temperature changes. You probably pushed the mirror against the cork when you refitted it. If you're using an OAG, you don't need to modify the cell. It's only needed if you're using a separate guide telescope or if you've unacceptable diffraction patterns around stars. As it is, your stars look to have the potential to be superb, so stick at it. Strange diffraction from the secondary spider too, as if you've used an altitude-azimuth mount. Any ideas? In any case, you're going to need more space between the sensor and the shoulder of the m48 connection. We find that most of the 2 element Baader ccs need closer to 60mm. Our first call would be: 1. to set the mpcc at 60mm and go with the OAG. Or... 2. stiffen the tube with a longer Losmnady dovetail with the guide telescope mounted on a stiff top rail. Both will need the mirror removed, silicone cleaned and replaced with the correct type and amount. Guidelines which work for us, here, the main part being [1] Seal the mirror to the cell using neutral silicone sealant, generous blobs to coincide with the gso cork. Leave the mirror to settle under its own weight on a horizontal surface, that a blob of the same sealant under the same ambience returns to its original form when distorted. Only then refit. Cheers and HTH [1] gso used but also tested with a 200pds, 130pds, bresser etc; the same applies to any low end Newtonian.

Hi Love it. Great result for such a short time. Superb star field showing loadsa structure and nice colour in the nebula. Well done.

Yes. Absolutely. There's loadsa detail already: But be careful with the camera orientation. Best to leave the camera attached to the telescope to avoid rotation..

Probably, yes. I'm certain that will be down to differences in eyesight and patience. For inspiration, we looked at Google images. It seems anything goes. Take your pick!

Hi We don't think the equipment counts that much. Far more important is to have clear nights with steady seeing so that you can get accurate guiding. The filter is certainly not needed; we prefer as little glass as possible, but in this case, the UHC seems to concentrate the blue/green of planetary nebulae without it looking unnatural. Certainly better than the new generation (read €silly!) multi pass filters. It also allows you to isolate and recombine the colour channels. To get any red though, you'll need to remove your 550d's hot mirror. Otherwise, wait for good seeing and just keep adding frames. The longer, the better; the detail will begin to emerge. IIRC, we used ~8 minutes. Cheers, thanks for posting and do post back your results.