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Dom543

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Everything posted by Dom543

  1. From the album: Widefield Lodestar

    85mm f1.8 Asahi Takumar lens, 6nm H-alpha filter, 5x60sec exposures mean stacked, Lodestar x2c with LodestarLive v.0.11, Live image captured with no post-processing.

    © Dom543

  2. From the album: Widefield Lodestar

    85mm f1.8 Asahi Takumar lens, 6nm H-alpha filter, 3x60sec exposures mean stacked, Lodestar x2c with LodestarLive v.0.11, Live image captured with no post-processing.

    © Dom543

  3. From the album: Widefield Lodestar

    85mm f1.8 Asahi Takumar lens, 6nm H-alpha filter, 3x60sec exposures mean stacked, Lodestar x2c with LodestarLive v.0.11, Live image captured with no post-processing.

    © Dom543

  4. From the album: Widefield Lodestar

    135mm f2.5 Asahi Takumar lens, IR-cut filter only, 5x60sec exposures mean stacked, Lodestar x2c with LodestarLive v.0.11, Live image captured with no post-processing.

    © Dom543

  5. From the album: Widefield Lodestar

    135mm f2.5 Asahi Takumar lens, 6nm H-alpha filter, 10x60sec exposures mean stacked, Lodestar x2c with LodestarLive v.0.11, Live image captured with no post-processing.

    © Dom543

  6. From the album: Widefield Lodestar

    135mm f2.5 Asahi Takumar lens, 6nm H-alpha filter, 10x60sec exposures mean stacked, Lodestar x2c with LodestarLive v.0.11, Live image captured with no post-processing.

    © Dom543

  7. From the album: Widefield Lodestar

    135mm f2.5 Asahi Takumar lens, 6nm H-alpha filter, 10x60sec exposures mean stacked, Lodestar x2c with LodestarLive v.0.11, Live image captured with no post-processing.

    © Dom543

  8. From the album: Widefield Lodestar

    180mm f2.8 Nikkor ed lens, 7nm H-alpha and 8.5nm Oiii filters, 4x60sec Oiii + 4x60sec Ha exposures live-stacked, Lodestar x2c with LodestarLive v.0.11, Live image captured with no post-processing.

    © Dom543

  9. From the album: Widefield Lodestar

    200mm f3.5 Asahi Takumar lens, 6nm H-alpha filter, 3x90sec exposures mean stacked, Lodestar x2c with LodestarLive v.0.11, Live image captured with no post-processing.

    © Dom543

  10. From the album: Widefield Lodestar

    200mm f3.5 Asahi Takumar lens, 6nm H-alpha filter, 3x90sec exposures mean stacked, Lodestar x2c with LodestarLive v.0.11, Live image captured with no post-processing.

    © Dom543

  11. From the album: Widefield Lodestar

    200mm f3.5 Asahi Takumar lens, 6nm H-alpha filter, 3x90sec exposures mean stacked, Lodestar x2c with LodestarLive v.0.11, Live image captured with no post-processing.

    © Dom543

  12. From the album: Widefield Lodestar

    200mm f3.5 Asahi Takumar lens, 6nm H-alpha filter, 3x60sec exposures mean stacked, Lodestar x2c with LodestarLive v.0.11, Live image captured with no post-processing.

    © Dom543

  13. From the album: Widefield Lodestar

    300mm f4 Asahi Takumar lens, 6nm H-alpha filter, 3x60sec exposures mean stacked, Lodestar x2c with LodestarLive v.0.11, Live image captured with no post-processing.

    © Dom543

  14. Thank you Richard. But credit should go to Paul's excellent stacking algorithm. That's what allows to suspend the process to change filters. And then continue and have the new frames' stars placed exactly on the stars of the earlier frames. Without that one would end up with ugly elongated stars and smeared nebulas. --Dom
  15. Amistybleu, My TS T-threaded filter drawer could be screwed in anywhere in your setup, where two T-spacers are joined. I believe that the only US reseller of TS producs is OPT and I believe that this is the drawer that you need http://www.optcorp.com/teleskop-service-1-25-single-filter-drawer-system.html The image is not exactly this item and the description is not good either. But it is likely the item you need, as TS has only two of these drawer systems: One with 2" filter threads on the housing and the other with T-threads on the housing. You should double check with OPT that the enclosure has one female and one male T-thread on it and that the drawer is for 1.25" filters. It makes sense to also buy additional drawers. The 1.25" drawers are the same and cost the same as the 2" drawers but also include an additional 2" to 1.25" reducer. (At AgenaAstro.com such a reducer alone is $20+.) If you unscrew the reducer, the same drawer can also be used with 2" filters. A possible alternative is the Orion filter slider system. "http://www.telescope.com/Orion-6-Slot-2-Filter-Slider/p/113381.uts?keyword=filter slider" or this "http://www.telescope.com/Orion-8-Slot-125-Filter-Slider/p/113380.uts?keyword=filter slider" I don't have this and have seen it only recently on the Orion website. It seems that it works as an eyepiece extension tube. You put it in the ep holder and put the ep or camera in its other end. A third alternative is to use a filter wheel. Almost every camera maker also makes filter wheels. But I don't have expeience with any of them. I believe that they are more expensive. Earlier, when I used light pollution filters and after Christmas, when I got my first H-alpha filter, I used then screwed on the end of the eyepiece. Since I have always had the parfocalizing ring on the camera, it was easy to slide the camera back to the same position after a filter change. I only started to use the filter drawer, when I got into these multi-color experiments. By the way, focus usually needs to be readjusted after every filter change. The only exception is, if you use filters from the same manufacturer that are guaranteed to be parfocal. Astronomik advertises that all their filters are parfocal. Baader says that filters of the same size are parfocal.
  16. No, right here on SGL http://stargazerslounge.com/topic/240669-photo-lenses-with-lodestar-for-widefield-eaa/ --Dom
  17. Amistybleu, You are right. If you want to play this multi-filter game that this thread has in its title, then taking the camera in and out to screw filters on and off is way too much distraction and may kill the fun. In that case a filter drawer, filter slider or filter wheel is the way to go. The filters can go between the reducer and the camera and 1.25" filters are sufficient. If you are interested in that, then we can maybe discuss that on the other thread, where I posted the photos about the equipment. That way everyone interested in the equipment involved can find all the relevant info in one thread. --Dom
  18. Amistybleu, Your setup looks good. You could also use this same setup with the 0.63 reducer. But since the spacing is less than required for the 0.63 reduction, you will get less reduction. Something around 0.8. In the long run it makes sense to add another longer t-thread spacer. You can always push the camera further in if less distance is needed. You know that the sensor of the Lodestar is 12.5mm inward from the front flange. If you look at the side of the body of the camera, you will see that is pieced together from a 12.5mm front ring and the rest of the body. Where the two pieces join, that's where the sensor is located. The easiest and least expensive way to attach filters to the Lodestar to have a 1.25" to C-mount nosepiece screwed on the camera's C-threads and 1.25" filters on the nosepiece. 1.25" filters are substantially cheaper and are plenty large for the Lodestar. I use 2"filters only because I have them. The filter drawer takes both 1.25" and 2" filters. There is a drawer insert for that. But, as said, until you will want to change filters quickly, the best solution is to simply screw them on the nosepiece. Best, --Dom
  19. Amistybeu, Currently I am travelling and away from my astro gear. I posted in a separate thread the setup that I use with photo lenses. For that I had the photos already taken. I use the same setup also with my SCT. The only change is that I replace the very first adapter (the one with the chrome flange on the photos) by a T-threaded 2" nosepiece. Of course, this setup is more complicated than minimally necessary, due to my desire to be able to change filters quickly. By the way, I posted my setup with an SCT and a flip mirror last fall here http://www.cloudynights.com/topic/144287-post-a-picture-of-your-assisted-visual-setup/?p=6210387 The flip mirror cannot be combined with the photo lenses as it way exceeds the allowed lens to sensor distance. But the short focal length lenses provide such a wide field that it is not a problem to get the objects on the sensor. So a flip mirror is not needed. If you want to know more about the flip mirror setup, then please go to my profile here on SGL, go to my content and you will find an entre thread there about the flip mirror, including photos. Please feel free to ask, if I can help with more info. --Dom
  20. I promised earlier to post photos of my setup that attaches the Lodestar to photo lenses and also allows easy swapping of filters. Here is my setup with the 180mm Nikkor f2.8 ed lens and Lodestar x2c. I have an assortment of old manual Nikon and Pentax lenses. I like them for their sheer feel that reminds me to an era, when precision craftsmanship enjoyed precedence to cost efficiency. They also make excellent and low cost short focal length refractors. The most used ones are this 180mm Nikkor f2.8 ed and the 135mm SMC Takumar f2.5. They have the right speed and frame many larger nebulas well. Here are all parts taken apart. I list the parts from left to right. 1. Tripod attachment ring (from ebay) bolted to a 4" dovetail. 2. Nikon lens to M42 adapter (from ebay). 3. Teleskop Service filter drawer with T2 threads (with drawer halfway pulled out). 4. 15mm T2 spacer. 5. Teleskop Service camera rotator. 6. Teleskop Service 1.25" eyepiece holder with T2 threads. 7. Lodestar x2c with 1.25" parfocalizing ring attached (the yellow plastic ring is just decoration). The 15mm spacer and the camera rotator are not essential. The round Lodestar can easily be rotated in the ep holder and with a parfocalizing ring it would not get out of focus. But since I had the rotator, I am using it. Also I feel more comfortable with the ep holder gripping the camera in its middle rather than at its end. For the Pentax lenses I just use a "Pentax M42 lens to Nikon adapter" (from ebay) added to the front of the setup on the photo. For Nikon lenses the distance from the flange of the lens to the sensor of the camera should be 46.5mm (for Pentax it is 45.5mm and for Canon 44mm). If the sensor is further away than one cannot reach infinity focus. The total length of whatever adapters and filter stuff is between the lens and the camera should add up to less than this distance. (Actually, less than 46.5mm - 12.5mm = 34mm due to the Lodestar's 12.5 mm flange to sensor distance.) I usually push the Lodestar a mm or two closer in. That way infinity focus is reached around the 100 yard mark on the lens. To use the Lodestar with an SCT I have this same setup. The only chnge is to replace the "Nikon lens to M42 adapter" with a T2 threaded 2" nosepiece. I have a Baader clicklock 2" eyepiece holder as a visual back on my SCT. The 2" nosepiece slips into this. So this is the setup. Please feel free to ask questions, if I can help with more details. A separate post will follow at a later time summarizing some of my experiences with the use of this setup for wide field electronically assisted observing. Clear Skies! --Dom
  21. Alex, I have been using a flip mirror with long focal length SCT's. Here is a thread with photos about it http://stargazerslounge.com/topic/227032-flip-mirror-with-two-stage-focal-reducer/ It not only facilitates finding and centering objects but also helps to alleviate my wife's suspicion of anything displayed on a computer screen. She can convince herself, by looking into the eyepiece, that the object is really out there in the space and not just created by an app or downloaded from a website. An alternative that I myself am planning to implement is to have a 50mm finderscope with a 1.25" eyepiece attached to the main OTA. I can then use the findescope to find and center the targets. But I can also move my Lodestar from the main OTA into the ep holder of the finderscope for widefild views. There are many beautiful large nebulae that require the wide field provided by a scope with less than 200mm focal length. Clear Skies! --Dom
  22. For comparison, here are three versions of my first attempt to use nonlinear DR mappings. They are all based on the exact same data. First linear. Fourth root. Arsinh. As said, these are only first tries and I am not particularly proud of them. On that night I wanted to do something else so I didn't spend much time plying with settings for these images. They may also be slightly out of focus. Clear Skies! --Dom
  23. I particularly like that you manage to keep the stars nice small and not letting them to overpower the more delicate DSO's. --Dom
  24. Hi Paul or Other Cognisanti, I am trying to use the non-linear DR mapping options (arsinh or x^0.25) but have difficulty to figure out how they interact with the contrast settings. The shape of the histogram changes dramatically, and sometimes into unusual shapes, when I move contrast slider. It might be helpful to know the internal order of processing steps that LL follows. Is this correct? 1. Debayering into 16 bit RGB space. 2. Brightness and contrast adjustment. 3. DR mapping and allocation (linear, arsinh, x^0.25 and black and white point settings). 4. 8-bit conversion. 5. Hue and saturation settings in HSV space. 6. Display. Or are 2 and 3 reversed? (In other words, does the contrast slider stretch the original (linear) histogram that later gets mapped? Or does contrast stretch the already mapped histogram?) Also, both non-linear options seem to de-saturate colors. Are they only B&W or am I doing something wrong? Thank you, --Dom
  25. Nice shots! I am curious, what are you doing to prevent the cores of the brighter galaxies from being blown out? Does the SX sw have some kind of HDR option? LodestarLive has two nonlinear DR mapping options but I have not mastered them sufficiently. Thank you, --Dom
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