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Welrod50

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Everything posted by Welrod50

  1. This is the finished article in DSS. 45 mins of 300 sec subs, x15 darks, x10 Offset, x15 flats. Finished in Photoshop. You can see the over bright centre area and the rings appearing in the image.
  2. It wont let me upload an original CR2 (or a converted 8bit DNG either). I know it's not as useful but I have therefore converted one to a jpeg so you can at least see how white it is. I shot this pointed at a bright but overcast sky through two sheets of white paper. I've already tried to edit this in Photoshop to see if I can introduce any darkening to the outer portion of the frame, but it remains pure white no matter what I do to it, suggesting it is pretty spot on already (unless you can tell me more and shed some light on the issue). Thanks for the continued help folks!!!
  3. This is a single sub edited in Photoshop. It is also representative of the final stacked image in DSS and is as good as the final stacked image gets too. Any ideas gang??
  4. Hi Ole, One thing I noted was that the centre of the frame was very bright (overly so) whilst the outer 30% of each sub was black. In PP in Photoshop, where I usually can process images well, I am seeing rings appearing and cannot balance the brightness in the inner 50% of the stacked subs with the increasingly darker and ringed outer regions. I have shot low in the sky last couple of sessions and although I have a 2" LP filter fitted onto the Mk 3 Baader MPCC, I do wonder if LP is playing its part. The 130 PDS is optimised for imaging so surely Skywatcher will have taken this into account when designing the secondary? I had a similar issue with my unmodded Pentax Kr before, but nowhere near as bad. I have done a bit more research and some head scratching today, and I believe my subs have been too long, too low in the sky and too near a sodium streetlamp nearby. I think the extra sensitivity of the modded Canon is coming into play and I am collecting light from outside the OTA. I will make a light shield for the base of the tube to keep any light out of the OTA and start from there. I am shooting through Mk3 MPCC with 2" LP filter screwed in. Mounted via M48 2" nosepiece as opposed to M42 1.5". I have attached a single unaltered jpg to show what my RAW frames look like. If this is edited and levels adjusted, it gives a good indication of the issues I am facing.
  5. Thanks for that I never imagined that there would be enough space at the bottom of the OTA to allow any light in as it does look pretty well made. As for the secondary, I also have no idea how big it is, but it makes sense to me that an APS C sensor would potentially have vignetting although the secondary can illuminate the EP area/eyepiece tube so why not a sensor? I have processed the images in DSS without darks, bias and flats and the result is much the same. The only thing I can think of is LP maybe, as my latest set were 300 sec subs at 400 iso. I will make a cover for the base of the OTA for next time and try that. I know I need to try something!
  6. Folks, I have a question I'm sure someone may know the answer to..... I've lately been shooting some iso 400 AP with my full spectrum modded 500D (simply as iso 800 is too noisy whatever the exposure time). What I am increasingly noticing is that the outer third of my stacked images are quite dark and develop rings in post processing. This issue is worse when shooting lower in the sky and when shooting much higher targets, is still there but not as bad. I had a crack at IC434 the other night and basically, the final image was unusable. It was low to the south from where we live and I do think some LP played a part, but I've also had a thought... Could the secondary mirror in my 130 PDS be too small to fully illuminate the Canon's sensor? Or am I barking up the wrong tree? As a bit of a side thought, should I make the jump to cooled ccd (which I've been thinking of for a bit to be quite honest) would something like Atik 320E or Starshoot G3 OSC be suitable for my f5 650mm FL scope? What might the resolution difference be? Please advise peeps Cheers Scott.
  7. I'm liking davefrance's idea personally. (Anyone seen that film Tremors??) And a good second place idea would be to dig a hole 18" across and fill it with concrete for each leg - solid, stable and mole proof.
  8. Agree with S@N suggestion. I also tend to buy All About Space, which is also a good read but S@N has a bit more variety overall.
  9. I reckon there are many forms of life out there, some intelligent, some less so and some beyond our comprehension of what lies beyond a cogniitive existence, and perhaps not only in our own galaxy, but many many others besides. That life I will suggest is likely in a different form to ourselves and with different abilities. There may well be living things in the cosmos more ancient than ourselves and others in their infancy (which we are if you consider the age of our race, in comparison to the age of our planet, to our star, to our galaxy and so on). For how long we have had the capacity to send and receive radio, it is unsurprising we have not received an answer. Perhaps, if there is a life form out there capable of discovering and building a radio transmitter, and assuming they receive our message, decode it into an understandable dialect and then send a reply, we may all be long gone before this response ever gets here. Lets face it in astronomical terms, we have been around for about 10 seconds and have had technology to send radio for about 1/1000th sec. There are perhaps advanced races out there, flying about in their star ships, teleporting between ships and throwing a dice to decide which galaxy to head for next - and then flashing light signals to their neighbouring ship, because they haven't yet invented a 'radio'. Who knows !!
  10. Sleep is indeed for the weak!! However, despite conditioning myself to survive on very little over the years, late working and endless cloud seem to burden me endlessly. Last time I did any astro at all was mid December. That's tragic!!
  11. Very good processing also. Nice
  12. Hi Lisa, from just down the road in Stoke
  13. OK, cheers for that. I am already using Baader MPCC with 2" LP filter which works well enough on the Pentax, and will be transferred directly to the 500D when it comes. I am using 130 PDS Newt. I reckon it should perform well enough. I did 60 mins (only due to technical issues and then cloud) on horsehead last night (x6 10 min subs) with the unmodded Kr and it picked up the nebulosity pretty well. The 500d should be brill Scott.
  14. Or if not specifically the EOS 500D, what about any full spectrum DSLR? Anyone had any experience or any head's up?? Cheers Scott.
  15. Hi all, Apologies if this has been covered before, but I tried a search and drew a blank, so here goes... I have tonight purchased a full spectrum modded 500D. As a current unmodded Pentax user, I wonder if there are any considerations I need to be aware of with the new camera when it comes? Mainly what I'm thinking is, as it's 'Full Spectrum' will I need to use any specific WB settings when I take the Flats etc etc. to prevent colour casts. No problem if I do, but as a modified DSLR 'virgin' so to speak, I wonder if there is anything glaringly obvious I have overlooked?? I assume the light frames, darks and bias should be straightforward, ( the darks and bias easy enough as they'll all be black) ? Thanks for the info in advance. I am really looking forward to testing this out when it comes, as 10 minute subs of NGC7000 with the Pentax revealed very little! Cheers Scott
  16. Mine looks much the same as yours too. Don't worry about it, just wait until you point it skywards on a dark night and it will fill with lovely stars. The hot pixels wont matter one jot. Honestly, don't worry about them
  17. The Kr is a legend at high iso. I used to use Kx, but the AA battery voltage dropped off too much in bulb mode and sometimes the shutter would not close, so I swapped to Kr for better power and the issues all went away I may have a crack at 1600 iso next outing just to see how much more the sensor will collect, but when I can get 10 minute subs at 100% keep rate with almost no noise I can't really see the advantage. I just need more subs!! (clear skies and less cloud please). Thanks again Guy
  18. Artificially darkened to compensate for over brightening. Anyway, hope it looks ok
  19. Hi all, Not posted for a bit so hello (again). Managed to get out on Monday night for the one clear night we've had in Stoke for an eternity when I haven't been working. Took me an hour to get set up properly and let PHD settle down, and managed six 600 sec subs of the lovely Andromeda, before some wispy cloud finally stopped play for the night. The EQ3 Pro is again making me smile with success! This is the first process and I do really need more subs to play with as 60 minutes worth with unmodded Pentax Kr is good but not enough. Watch this space... EQ3 Pro. SW 130 PDS with Baader MPCC Mk3 Unmodded Pentax Kr (running through PK Tether) SSAG kit through PHD Will have to figure out how to save a screenshot of the graph in PHD. RA & Dec were bob on all night without fail, each just peaking above and below the centre line like a little heart monitor. I say again, spot on polar alignment and a little bit of time setting up properly is well worth it!! For now, this is what I've got. C+C most welcome Just for info - my calibrated screen displays this very well, but upload is very bright on here & has halo's on the extremities :/
  20. Isaac Newton. He could get a right ego boost knowing he was responsible for the legacy of the Newtonian, and he could have a look through a decent EP with quality mirrors to inspire him that bit more.
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