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Showing results for tags 'canon 300 f4 l'.
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It turns out I can not acquire more data until this challenge ends. I present you therefore what I have until now. It's a 5 panels mosaic in Hydrogen alpha. 3 panels in portrait mode, at the top. And 2 in landscape mode, at the bottom. Each panel is made by 30-31 subs of 300s and for the Orion nebula core I have a few 15s subs. All subs are taken with the ZWO ASI 1600 MMC, cooled to -15C, and 139gain. The lens is a Canon 300 F4 L with a lot of distortions caused by the IS element. Compared to the images I was taking on other targets until Orion rose enough, the focus was good since the beginning and remained ok during the nights. Mount: AZ-EQ5. Guiding with a 200mm lens. Software used: APT and PHD for acquisition; DSS, APP, Registar, StarTools and GIMP for processing. I plan to acquire 4 more Ha panels in landscape mode to cover the same area to increase the SNR and then to move to O3 and LRGB. A lot of work this winter. Link with wip: http://www.astrobin.com/317154/C/ Thanks and clear skies, Alex
Hello all, I've been capturing photons lately on the IC1396 with a Canon 300 F4 L lens on an ASI 1600 MMC. I did that for about last month during which I didn't take the camera and the filters off the lens. My balcony is pointed towards ~NEE so I can only see and image the sky between ~30 and ~140 degrees in azimuth and up to ~50 in altitude (with some tricks I can extend that). I shot the Ha sometimes also with the moon still up in the sky, sometimes without, when the trunk rose above ~25 degrees in altitude, the O3 above ~30 degrees and the S2 above ~25 too. In total I have 10h of Ha, 6h of O3 and 5h of S2 taken during 4, 3 and 2 nights respectively. Last night was a pain with the S2, the download from camera freezing twice and guiding going weird. Anyway, this was the last clear night, the forecast says that is going to be cloudy for a while and even if it clears, the moon will interfere so I won't get more data for a while. Perhaps I will switch to something else. All subs are 300s at gain 139 (unity) and cooled to -15C. All calibration frames. The O3 flats looked a bit weird so I took them twice and combined the 2 results. I can't really describe the final combination as it was more trial and error / like/dislike. The L is ~75-80% Ha and O3 and S2 equally filling the rest. The RGB was combined in StarTools and in GIMP, the layer combined in StarTools having a much higher percentage in the final blend. All processing done in StarTools and GIMP and the resizing/aligning was done manually in GIMP. I don't know if I missed something about the acquirement and the processing. The lens seems to have some element tilted, you can see some coma in the bottom-left corner and bloated stars in the top-right one. Better than no lens/scope though and at F/4 is quite fast. This would be my longest project and the most detailed one (highest resolution). I think I could get a better result from processing, but it takes ages at full resolution. Therefore I call this the final result (for a while at least). I'm also attaching the Ha, O3 and S2 channels. Comments and critics are welcomed. You can also follow the progress and the testing for this target at bin2x2 here: Thanks for looking and clear skies, Alex
I really hope that I need a single more night to complete my belt to sword 4 panels mosaic in O3 so I can finally put the ASI1600 on my new Esprit 80. Meanwhile, I carried where I traveled last 2 weeks the EQ5, the Esprit and a Canon 550D. I also had a chance yesterday to shoot some images with the same setup from home, where the sky is light polluted. First image is a total of about 30 mins of 30s unguided exposures with some moon too, but under dark skies + about 30 mins of 90s exposures from home, guided. Some 10s exposures too for the core. Perhaps the focus was not always spot on, the scope is more sensitive than I expected and it shifts quite a lot due to temperature drop. Second image contains Ha and O3 data I'm collecting for the mosaic above mentioned, added in a rather small amount. Even if I need much more data and the result is far of what I want, I'm pretty pleased with my improvements in time. The third image was taken at Christmas, 2 years ago, at my first or second astrophoto sessions. 102/500 achromat on an Alt-Az mount. Clear skies! Alex
Yesterday evening was clear and I just bought a Canon 300 F4 L sh a week ago. Didn't want to take out all the heavy mount, power supplies, camera, etc. and it would even have been impossible perhaps to set it up in time. So I took the EQ5 with RA tracking (powered from an USB power bank), the lens and the Canon 550D. Went somewhere outside, the galaxy was just visible, but much, much better than city lights. Had a look before at Venus and at Orion's nebula with the 100 F5 achro then I put the camera. I also recently bought a polar scope for the EQ5 and it was the first time when I aligned a/the mount using the polar scope. The circles were much darker than I would have expected. I tested then the tracking with 30s exposures and it seemed to track without trailings, but I was a little afraid so I set the exposures to 20s. I don't have an intervalometer so I couldn't even try longer than 30s with just the camera. I made a manual trigger though so I could fire it up with the camera set on continuous shooting. During the night tracking seemed to stay on spot, I had to refocus once. It was pretty cold, about 5C maybe and I stayed inside the car. So I took more than 200 exposures of 20s at ISO1600 and aperture wide open at F/4. I used about 220 of them. I also took about 60 5s exposures to use for the stars. I'm pretty impressed by the lens' resolution, though I suspect that stopping it down it could help even more. For comparison, I'll attach another try from early October, but taken with 2 Tair 3s lenses stopped down at F/5.6, put on a Canon 550D and a Canon 450D. If I remember well, I exposed then almost half an hour before the batteries went flat. So the total light acquired yesterday was more than double. But the sky was not as good. I also added about 2 hours of noisy Ha to the image, taken from the city with the ASI 1600 MMC also with the Tair 3s and Optolong 7nm Ha filter. I don't think I can make it look much better. Enough writing so here are the images. The colour ones with many spikes are the old ones taken with the Tair lenses. Clear skies, Alex