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stan26

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Everything posted by stan26

  1. This is so true Stuart I couldn't agree more, and not just astro either, all types of photography! I find PP the most challenging aspect of photography especially DSO work. IMO a lot of the time its what makes a good photo into a GREAT photo!
  2. Dave, Sorry i should have been more clear, i really need the Tiff file that you got out from your stacking software, I'm just not sure how you could send it too me. as the upload limit is 20mb on here and your tiff will be around 70mb. Maybe someone else will know the answer? Failing that you could use a site like file dropper to send it to me..? Once I have the tiff with all the info/data it holds I can have a play and talk you through it. Stan
  3. Cheers guys, i may have an arm wrestle with Alnitak later! I forgot to mention, these subs where ISO3200!!! hense a bit of noise about it, however I have done "some" selective noise reduction in areas. Dave, what ISO where you using..? and is your camera modded or not...? The basic method I use to get the initial nebula to show is this.... I load the stacked tiff in photoshop (complete linear file with no pre stretch done in DSS so it looks black with a few stars) I then go straight into curves and pull the curve roughly half way across to the left (obviously this will vary from image to image) press OK I will then do this another couple of times, making the image brighter and revealing more detail on each basic stretch. After a few stretches I will then go into levels and select each individual RGB channel seperately and pull the black point slider (far left slider) right toward the start of the histogram peak so that the slider meets the start of the left side of mountain looking bit. I dont quite go right up against the peak because I dont want to clip the levels. I do this with each colour channel untill the image is looking correctly balanced colour wise and obviously darker and more contrasty. I will then go back into curves and do the above all over again but with smaller adjustments teasing out a bit more detail each time, but being careful not to blow any highlights (bright areas in the image) if this happens, back off a bit. I will often use individual RGB channels in curves too to get the colours I want. This gets me to the point where I have the detail revealed, now all the little tweaks need to be done..... Maybe this helps..? I will happily look at your stacked image and see what I can do with it and explain what/how I do it if that helps...? Stan
  4. ....Not recommended! I wanted to see what the little astrotrac could handle. After a few tweaks of my DIY wedge I was managing half decent 2min subs with my Skywatcher star travel 102 achromatic refractor. Naturally the final stacked tiff was a processing nightmare, blue halos,flaring, field curvature, lack of contrast and colour compared to my Canon 200 L lens. But it was able to bring the subject closer than my lenses and that was the point of using it. The massive flare artifact around Alnitak is staying put! that would require too much butchering of the image to sort out, besides I think it adds a little character! 1.5hrs of 2min subs, Modded Canon 1100D, Hutech IDAS filter, ST102, Astrotrac TT320, DIY wedge. 150 x Bias, 20 x Flats chucked in too. (don't look too close) Stan Flame and Horsehead nebula. by James stannard, on Flickr
  5. haha cheers guys, and thanks for the re-arrangement Peter thats great! Happy new year all! Stan
  6. Thanks Guys. I actually rushed the processing of the original image, I had no intention of it being the final version when I started messing with the data in PS, I was hoping to add a few more hours but when I started seeing what was being revealed when stretching the histogram (jaw hit the floor moment) I got carried away and decided to go with it as a final version allowing me to move onto the next target (rosette neb) I have reprocessed the 1500px version to give it a smoother finish, The original although exciting with all the colour and detail had (i thought) a very "hard" finish to it especially the stars, so in this 1024 version I have (i think) slightly improved the overall image which although looks smoother actually has no noise reduction and less sharpening too. others may disagree, either way I'm still learning the black art of Deep sky imaging. Mods - If you have the capability please feel free to move the new version image back to the top, I can't seem to edit my first post..? Stan Orion to the flame. by James stannard, on Flickr
  7. Thanks folks. I'm tempted to re process it to get some better looking stars, I struggle with "toning them down" and keeping there shape. I might clip the background a tad more too..... Cheers.
  8. Thanks folks. I'm tempted to re process it to get some better looking stars, I struggle with "toning them down" and keeping there shape. I might clip the background a tad more too..... Cheers.
  9. Taken over the last few nights, some most frustrating imaging sessions i have ever had with regards to getting the astrotrac aligned. I sort of gave up in the end and carried on with 5minute subs, however the end stacked image didn't show the trailing as bad as I initially thought it would. Just over 3 hours total exposure in the final stack, although I took nearly 5 hours of data, passing wispy clouds ruined a lot of them. Astrotrac TT320, Modded Canon 1100D, Canon 200 f2.8 L (@2.8) ISO400, Hutech IDAS MFA Filter. 3 Hours of 5minute exposures, and 10 x 30sec for M42's brighter parts. Stacked with bias and flats in DSS and processed in Photoshop CS2. I'm thinking of grabbing more data tonight but the last two (2:00AM) sessions have nearly killed me so I may give myself a rest for now..... although I hear the "rosette" calling........hmm..... Stan Orion to the flame. 1500px by James stannard, on Flickr Reprocessed.... Orion to the flame. by James stannard, on Flickr
  10. Thanks for your replies folks, Stuart your last suggestion about the wedge bolts being too tight may be bang on, ever since I have been using the wedge I have had this issue, although it has got worse over the last few sessions. Think I'll look at this first.... Thanks Stan.
  11. Hi Guys, I'm tearing my hair out with this! My astrotrac has always been very accurate with 5min + subs not a problem at 200mm, but over the last few sessions I haven't been able to get rid of star trailing. It has a fully charged 12 car battery so I don't think its a power issue. I have it bolted to my wedge which is very sturdy and very accurately adjustable and proved to be great the first few times I used it. Now I seem to get trailing (very elongated stars) in the RA axis. I have spent hours trying to drift align the wedge but still can't get rid of the trailing. For example I start my drift align on a southern star, it drifts up and right indicating a north drift. I adjust and az bolts and the the north drift reduces nicely but im still getting east - west drift. I get to the point where I slightly over adjust so I start getting south drift so I back it off so that I'm now not getting any north/south drift on a southern star BUT its still trailing east west. I try aligning the north south misalignment on a western horizon star with the exact same results, i always manage to dial out the north south drift but never the RA axis east west drift if that makes sense...? Am I doing something wrong..? Could there be something really obvious I have over looked...? Cheers Stan
  12. So far so good, tonight's drift align yielded perfect round stars with 5 minute subs at 200mm in both the southern and western sky. The fog rolled in before I had a chance to push it further. I'm amazed at how finely adjustable it's turning out to be. I would love to get 10min subs at 200mm but I'm not sure if an unguided astrotrac is up to it. Either way I'm going to give it a go!!
  13. Cheers Guys, when you consider the cost of wedges, i.e the astrotrac wedge which is £300!!, if this "does the job" for a fiver I think I'm onto a winner! Stuart - I have an empty 25ltr plastic drum with the bottom cut off which I place over the top of the wedge held down to the pier post with bungies. Any moving part will be getting a coating of adhesive lube to help protect it further. My poor old pier is looking a bit "weathered" now
  14. Okay, so its currently a little rough around the edges so don't look too hard! and I broke my last hacksaw blade which means there are a few bolts to be cut down to a more sensible length, but otherwise it all seems to work a treat! I originally brought the astrotrac to get out in the country side away from the LP, but now the missus works evenings and I need to be at home to look after the little ones, that doesn't really happen anymore. So I need to make use of the astrotrac at home. The Giottos tripod and manfrotto 410 geared head that I have are OK for the astrotrac but its still a bit of a challenge to get it polar aligned for any lengthy subs, and still a little flimsy. I want to get the best out of the astrotrac and for this I need a sturdier mount and ideally something I can leave permanently polar aligned.......I just happen to have a concrete/steel pier in my garden! so the next step was to make/adapt an adjustable wedge that can be bolted onto it. The only materials I had to buy was the two pieces of 6.5mm Alloy plate sourced from a local fabrication workshop for £5 cash. The rest of the hardware/materials used were found at home. The reason I went for the 6.5mm alloy plate is because its very easy to work with, even with your average Argos mickey mouse tools/drill bits you can soon whittle out the require holes/shapes, plus its very sturdy, good enough for the astrotrac and camera/lens combo. Its fully adjustable in both alt az. The azimuth is adjusted using bolts that go through bed nuts that are sunk into the two square tubed lumps bolted on each side. The adjustment bolts go up against another upright bolt that is threaded through the pier base and comes up through a slot cut out in the bottom plate of the wedge to allow it to move about an inch left to right (or west east), just like adjusting the az on an EQ mount. The black knobs are from an old vixen refractor I cut up to make into a guide scope. The hinge nuts are countersunk into the plate to allow a completely flat surface for the astrotrac to lay flush against. The astrotrac is held in place by 3x 4mm threaded rods and wing nuts. This means is super solid and bolted in the same place each time. Once aligned I will carefully tighten the main M14 center lock nut to hold it all firmly in place. Its a bit crude, but its the best I could do with limited money and time to spare, Its a also stronger than the pictures suggest, once everything is tightened its absolutely solid with no play/flex. I reckon even if I had to buy everything used it would have still came in under £30. Hopefully I 'll get a chance to use it tonight and assuming everything is okay I will make it look a bit more pretty and then carry out a drift alignment.. Stan
  15. Cheers QM, Yes the astrotrac is a wonderfully simplistic bit of kit, I just need to tweak my wedge alignment for these long exsposures, theres still a bit of trailing in there. Periodic error is almost non existent at telephoto FL's upto 400mm. With the wedge bolted onto my old EQ pier I reckon I can be setup an imaging in around 2minutes! Cheers Stan
  16. Thanks Guys. Tim - There was no dew present throughout the session, I think the halo's are a result of the IDAS filter. Its the rear mounted MFA version and I think I maybe getting some internal reflection off the brighter stars. When I minimised the stars I could have greatly reduced the halo's but I didn't think they were to distracting so I left them in the image. Cheers Stan.
  17. 1hr and 15minutes data total, but this time and for the first time ever I imaged using my 200L lens "wide open" at f2.8. In the past I have always stopped it down to around f4.....I'm now realising that stopping it down in the past could have been costly in terms of photons..... Modded Canon 1100D, ISO800, 5minute subs, Canon 200L f2.8 (@f2.8), Hutech IDAS P2 MFA filter, Astrotrac TT320 bolted onto DIY wedge. Stan Hope the pic loads...? (new flickr is confusing)
  18. Good luck QM! I take my hat off to anyone attempting to computer control there EQ3-2 / EQ5 mount, I can fully appreciate the challenges that lay ahead, I hope you stick at it longer then I did! It now seems like years ago that I was doing the whole "guiding" thing with my EQ3-2, I'm sure I have forgotten most of what I learned on that very steep learning curve. I was hunting for something earlier in the garage and came across a load of cables, USB connectors and a rather sorry, dusty looking quickcam pro 4000 webcam. It was soooo cool the first time I go the EQ3-2 guiding, I couldn't believe I was getting 3min+ subs with perfect round stars at 500mm FL. I sold the EQ3 and moved onto a old black HEQ5, but I had more problems with this mount then I did with the EQ3-2! Although I enjoyed the technical side of guiding with these type mounts, it became increasingly frustrating getting it all set up only to watch the clouds roll in, or find that PHD would not play ball. A complete astrotrac setup came up on astrobuysell so I took a punt and went for it.......iv never looked back! I was and still am completely blown away by the capability of these devices it takes a few minutes to setup and i'm straight into 5min + subs with my telephoto lenses. This saved the day for me and astrophotograhy. I will follow this with interest
  19. Hello Guys, i'm not sure what to do here. I have just purchased the above a Hutech IDAS MFA kit from FLO (which I may add was a fantastic experience, ordered 1pm friday, arrived on my doorstep 10AM Saturday!!) great service guys! However, after doing some trial runs last night using my modded Canon 1100D, and Canon 200L f2.8 prime and I think I have discovered a potential drawback of using such rear mounted interference filters...... "red halo's" around bright stars. I have seen a few topics on the net covering this issue and it seems to be mostly related to camera lenses and rear mounted filters such as this one and the astronomik clip in's..?? which is typical because lenses are all I use these days! I now need to make the decision of whether I can live with it or not and put up with dealing with them in post processing. Has anyone else experience these halo's using camera lenses/rear filters but have seen them disappear when using the same camera/filter setup on an APO refractor..? I'm 100% convinced its to do with the fact the filter is mounted at the rear because I once used a Hutech IDAS p2 "front mounted" on this SAME lens with a modded 450D and didn't have any red halo issues at all, and I have plenty of subs in the Iris nebula region sitting on my hard drive to prove this. So my guess is - (front mounted version filter) the light channels are filtered first and then the light channels are focused by the optics to point X "vs" rear mounted version where the optics focus the light channels at point X first and THEN it is filtered = two different results. Or could it be the reflection of a certain wave length bouncing off the filter onto the lens optics...? One good this about the filtered stars are they are noticeably smaller/tighter, I guess this is the filters IR/UV blocking characteristics along with the fact it interferes with the broadband light source. Other than this, it does a pretty good job of controlling the sky glow hmm.... ( the blue'er images below are 5min subs without the filter, the reddish images are exactly the same setup/conditions using the filter. The comparison image I have overlaid both images at 50% opacity and offset one to aside so a quick easy comparison of the stars can be seen. You'll notice how the pinkish halo stars are smaller)
  20. Hello guys, I have often wondered but never found the answer.... The faint background browny reddish dusty stuff you get around a lot of DSO's, in terms of photons and capturing it what actually is it..? i.e is it emission or reflection dust..? or neither..? How does it appear in some of my images, obviously it is sending light to our sensors but how..? The reason I make the effort to ask on here is, I'm considering the Astronomik CLS CCD filter to help capture the fainter stuff from my moderately light polluted back garden, however if a lot of the faint dusty stuff is reflected light I guess its not going to help me much given is pass bands...? For example I would like to capture the faint brown stuff around orion, but will a CLS filter help or hinder..? Any thoughts? Stan
  21. Thanks guys, actually my Sig is out of date, I'm actually using a modded 1100d for astro and a 50d for daytime. Whilst I appreciate that the overall iq will decrease and the af will struggle, the only thing I'm really concerned about is the amount of light reaching the sensor with the added optical elements. With regards to this I guess a similar focal length similar speed doublet APO will always out perform it, or is this not the case? Regards
  22. Guys/Gals, just wondering if anyone has tried this, and had any sucess....... At the moment my longest good quality (APO) Focal Length is my little 200mm f2.8 L lens, which is absolutely fantastic at wide field work, but struggles with alot of objects. Whilst im not looking to point the camera toward the smaller targets, galaxies etc, I would like to image the "larger" DSO at a bit more FL. For example, M42, M45, the rosette etc are all framed a tad too wide for my liking at 200mm, I want to get a bit more up close and personal. I have worked out that I basically want to double my FL to 400mm. I have recently simplified my AP setup by moving away from guided EQ mounts and moved over to Astrotrac (now my only method of tracking the night sky), so naturally im geared up for widefield work, and obviously have weight limitations. I initially started looking at small APO's on the market. I think somthing like a William optics ZS71 (f5.9) would do the job quite nicely, but I would require a flattener/reduced (f4.8) and this would set me back around £460 all in. However, I could buy a Kenko 2 x converter for the L lens which would give me a 400mm F5.6, with (in theory) a nice flat field, for £130........ You see where I'm going here..... Any thoughts... (edit: im working on a very tight budget here, and sturggling to justify to myself and the missus the need to spend nearly £500 on "another" telescope) Stan.
  23. That's absolutely stunning Olly! Stan
  24. Thanks guys! Dave - The astrotrac amazes me every time I use it. It takes 2min's (max) to polar align it, and with the 200mm lens I can go for 5min subs from the right location. Focus is achieved manually just using a bahtinov mask. I always let the lens cool outside for an hour before I focus it. Cheers Stan.
  25. Wow, that's a great image! and a great setup, love my 200L 2.8
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