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ollypenrice

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ollypenrice last won the day on October 19

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About ollypenrice

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    les.granges@hotmail.co.uk
  • Website URL
    http://www.sunstarfrance.com
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    ollypenrice

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    Male
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    Imaging, Cycling, Thinking, Literature, French culture, Mountains...
  • Location
    South east France, Lat 44.19N.
  1. If anyone's worried about this being OSC I'd say 'Don't be.' For many years I guided with both a mono and OSC Atik 16ic on different rigs and, to be honest, found no difference between them whatever. I'm surprised it hasn't gone. I'd love to swap my Mk1 Lodestars for Mk2s because of the improved cables and sockets. Olly
  2. ollypenrice

    50h on Flaming star and Tadpoles - LRGB-HOO

    Thanks. Maybe I should try some because the tadpoles are a bit lost in my HaLRGB rendition. I control overly bright stars by 'reverse processing' them. Make a copy layer and use a soft edged eraser somewhat larger than the star and its bloat. Centre it over the star and apply it once, to make a feathered 'hole ' in the top layer. Now work on the bottom with the top still visible. In Curves fix the background outside the bloat exactly where it is and put a fixing point below that. Pull down the curve above that, shaping it till you get a smooth, smaller star and no signs of manipulation. This usually increases the saturation of the star so that, and its colour balance, can be adjusted to taste. It might be worth doing this only to the blue channel but that can be really tricky. Olly
  3. ollypenrice

    Telrad ?

    Mine too, by a country mile. How I detest the ones with watch batteries which die if you leave them on. I've left my Telrad on for a month and still not flattened the batteries. I think my oldest Telrad is now twenty. Olly
  4. ollypenrice

    Tonights Veil TIFF files

    Nice. Maybe bring the black point in a tad? Olly
  5. ollypenrice

    50h on Flaming star and Tadpoles - LRGB-HOO

    This is good and could, I think, easily get better. Looking at it stone cold and not reading your method, I thought it had the look of an image with too much Ha in the luminance channel. This results in the image coming out very pink with blue haloes around the hot stars. I also think the Ha in the background is a little high and, like Richard, I think this diminishes the contrast between the strong Ha structures and the faint ones. Personally I would make the LRGB image and process an Ha with exaggerated contrasts and the background held down. I'd then add this to the red channel in blend mode Lighten, maybe giving it a tweak in Curves to make sure the background wasn't affected but that the bright signal was coming through strongly, flatten and re-combine. I might then try the Ha as luminance but only at a very low opacity, probably not more than 15%. I'd add the OIII to the blue from the HaLRGB in the same way and then add it to a separate copy but this time to the green. This allows you to put the 'OIII to green' on top of the 'OIII to blue' and balance the green-blue contribution of the OIII. (I've never shot OIII for this. Is it fairly strong?) Olly
  6. ollypenrice

    ngc 7789

    It's frustratingly close. In this version I adjusted the Hue in Ps Hue and Saturation. I added 20 to the Hue in the Cyans and 10 to the Hue in Reds. I may have been wrong about the reds being too yellow. My alteration makes them more so and yet they look better to me. I don't know what you feel about them though. I do prefer these blues with less cyan. Most graphics programmes will have a Hue adjustment, I think. Olly
  7. ollypenrice

    takumar 200: do I need to guide?

    What matters is the pixel scale rather than the focal length. You'd be imaging at 4.4 arcseconds per pixel I think. The PE of an EQ6 is in the 20 to 30 arcseconds area over a full turn of the wheel which is 8 minutes, from memory. So it doesn't look good! However, if you have equal and random errors you may get fairly round stars, though this is no indication of real resolution. 4.4 arcsecs is not particularly tolerant. Our Tak rig works at 3.5"PP on a mount with a PE of less than 3 arcseconds and we certainly need to guide it. Olly
  8. ollypenrice

    ngc 7789

    I've tried with your colour a couple of times (just on the screen grab) but never found a satisfactory solution. I don't know how you see it but to my eye the blues are too cyan and reds too orange or yellow-orange. I'd be happy to run the TIFF through PI's colour calibration. I know you don't use PI but it would be interesting to see if it could fix it. There are various routines for colour calibration in PI but the most interesting is the photometric version which identifies the object and uses the astrophysics of the target to set the colour. I still think that in a target with faint nebulositiy you'd be losing data. Olly
  9. As Wim says, no IFN here. The IFN is much harder to find and even harder to find in colour. However, the dusty features you've brought out are in good agreement with those of my very long exposure M45 so we can't both be inventing them! (I'm always wary of 'creating' features in the faint stuff so comparing one's results with others is a good idea.) Olly
  10. The first thing I'd do is make a stack without the flats. This has most of the hallmarks of over-correction, with some oddities thrown in for a challenge. Maybe give the no-flats image a stretch but nothing else and post it up? The fact that you did your flats as usual doesn't mean they can't be wrong. The blessèd things have a mind of their own! Olly
  11. It's certainly true that the seeing often over-rides the best efforts of the mount in high resolution imaging. I'm glad our EQ6 delivered the goods for you! It didn't do quite so well the week before last but there are any number of variables in a temporary setup. Maybe I err too much on the side of caution regarding tracking. It's just so exasperating when it won't deliver. If the OP isn't going to image with the C9.25 you have a good point here. I'm still not ready to jump ship from CCD to CMOS, though. Olly
  12. ollypenrice

    ngc 7789

    What programme is this? The histogram you're showing in Curves is partially hidden on the left by the white dot at the bottom of the Curve line. To my mind the Levels histogram I took from Photoshop clearly agrees with what we see in the image. The sky is a featuresless jet black with a value ranging from 9 to 14. There is no background value we can deem to be 'correct' but most imagers are looking for values between 20 and 23, the most experienced erring towards the higher value. Of course, we're dealing with the JPEG here. It would be interesting to experiment with the linear TIFF. Does your programme allow you to view the histogram in Levels? Olly
  13. ollypenrice

    JamesF's observatory build

    I pick mine up on the Duster's roof rack. Just be careful to prevent the sharp edges from sawing through any tie downs that you use. This certainly happens, as I know!!! I've used flat steel sheet on our summer kitchen's fixed parasol but you have to bolt it down only at one end and hold the rest down under wooden or steel strips which allow it to expand without buckling. Why does corrugated steel not buckle along its length? Maybe it tries to but the corrugation simply prevents it. Expansion in the other axis can be absorbed by deepening the peak to valley, of course. This is a great observatory in the making. Olly
  14. ollypenrice

    Refractor For Galaxy Imaging

    Alas, Gav, there I cannot help you and I doubt that anyone can! lly
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