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ASTRO: NGC 3448 (Arp 205)
I used two nights (March 4 and 6) for this image of NGC 3448 (Arp 205). The
first night had some moonlight and only mediocre transparency, but good seeing. The second night had mediocre seeing but very good transparency, giving me a record background brightness of 19.0 magnitudes measured with SQM-L. A "normal" good night does have 18.7 mags around here. The difference of 0,3 mags does not appear to be a lot, but it meant a reduction of background brightness with this setup from about 8400 ADU to 6300 ADU. When I took this image I did not know that there is another galaxy (UGC 6016) to the right of NGC 3448 as this galaxy is not shown in Guide 8. I thought it was part of the tidal tail of NGC3448. When I searched for pictures of this object one of the few I found was made by Rick J. who's picture was deeper (of course). Taken from the middle of Berlin with a 10" Meade ACF scope at f/7.2 (AP reducer) on a G11 mount, SXV-H9 camera, 50x5 minutes for L, 12x5 for R and G plus 18x5 for B, colours with 2x2 binning. http://ccd-astronomy.de/temp3/3448colourgut.jpg Stefan |
#2
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ASTRO: NGC 3448 (Arp 205)
Stefan Lilge wrote:
I used two nights (March 4 and 6) for this image of NGC 3448 (Arp 205). The first night had some moonlight and only mediocre transparency, but good seeing. The second night had mediocre seeing but very good transparency, giving me a record background brightness of 19.0 magnitudes measured with SQM-L. A "normal" good night does have 18.7 mags around here. The difference of 0,3 mags does not appear to be a lot, but it meant a reduction of background brightness with this setup from about 8400 ADU to 6300 ADU. When I took this image I did not know that there is another galaxy (UGC 6016) to the right of NGC 3448 as this galaxy is not shown in Guide 8. I thought it was part of the tidal tail of NGC3448. When I searched for pictures of this object one of the few I found was made by Rick J. who's picture was deeper (of course). Taken from the middle of Berlin with a 10" Meade ACF scope at f/7.2 (AP reducer) on a G11 mount, SXV-H9 camera, 50x5 minutes for L, 12x5 for R and G plus 18x5 for B, colours with 2x2 binning. http://ccd-astronomy.de/temp3/3448colourgut.jpg Stefan Now this is one heck of a coincidence. I just finished reprocessing this one. I did this one before I really knew how to process images. Mine was very noisy and color way wrong. Also I'd so stretched the image to bring out the faint fuzzies and plumes I completely lost tha really wacky dust lane. I was quite shocked to see it appear in the reprocess. Now here it is in your image. I checked my image and my background was 526 which I consider high. I much prefer one of about 250 to 300. Not sure what made this one so "high". How you do so well under your skies simply amazes me. Rick -- Correct domain name is arvig and it is net not com. Prefix is correct. Third character is a zero rather than a capital "Oh". |
#3
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ASTRO: NGC 3448 (Arp 205)
Rick,
thanks for sending me the reprocessed version by email. Why not post it? It's better than mine, but I don't mind :-) Nobody will notice anyway, as nobody looks at "exotic" pitures. At least that's the case in the german board where I post my images, you get a lot of replies to the 200th "wide field Leo triplet" picture, but nobody seems to notice such small galaxies ;-) Stefan "Rick Johnson" schrieb im Newsbeitrag . com... Stefan Lilge wrote: I used two nights (March 4 and 6) for this image of NGC 3448 (Arp 205). The first night had some moonlight and only mediocre transparency, but good seeing. The second night had mediocre seeing but very good transparency, giving me a record background brightness of 19.0 magnitudes measured with SQM-L. A "normal" good night does have 18.7 mags around here. The difference of 0,3 mags does not appear to be a lot, but it meant a reduction of background brightness with this setup from about 8400 ADU to 6300 ADU. When I took this image I did not know that there is another galaxy (UGC 6016) to the right of NGC 3448 as this galaxy is not shown in Guide 8. I thought it was part of the tidal tail of NGC3448. When I searched for pictures of this object one of the few I found was made by Rick J. who's picture was deeper (of course). Taken from the middle of Berlin with a 10" Meade ACF scope at f/7.2 (AP reducer) on a G11 mount, SXV-H9 camera, 50x5 minutes for L, 12x5 for R and G plus 18x5 for B, colours with 2x2 binning. http://ccd-astronomy.de/temp3/3448colourgut.jpg Stefan Now this is one heck of a coincidence. I just finished reprocessing this one. I did this one before I really knew how to process images. Mine was very noisy and color way wrong. Also I'd so stretched the image to bring out the faint fuzzies and plumes I completely lost tha really wacky dust lane. I was quite shocked to see it appear in the reprocess. Now here it is in your image. I checked my image and my background was 526 which I consider high. I much prefer one of about 250 to 300. Not sure what made this one so "high". How you do so well under your skies simply amazes me. Rick -- Correct domain name is arvig and it is net not com. Prefix is correct. Third character is a zero rather than a capital "Oh". |
#4
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ASTRO: NGC 3448 (Arp 205)
I've noticed that on all boards I've checked. Everyone wants to see how
someone else did with something they've imaged. New things they haven't imaged are meaningless since they never imaged it. I take the opposite view. If I don't recognize it by name it's the first thing I look at. Then I check the declination and see if it is something I can see. Often it isn't but if it is it goes on my to do list. I've been imaging now for over 50 years. I'm really tired of the normal objects. I've imaged them several times with film and now at least once for most with CCD. I've seen a gazillion different versions including three or more from most of these imagers you refer to. Seems most are more interested in trying the old stuff a slightly new way than going for something new and likely more challenging. Seems boring to me. And you I'm sure. If I got a new scope or camera I can see doing some object I've done with the old system for a comparison. But if I get a new system it would be to do very different imaging than I'm currently doing -- wide field in my case. I keep thinking of going that route but each time I look at the to-do list and think I need to finish it first, of course it grows faster than I can image so that will never happen. Too many objects, so little time. Of late I'm hearing from grad students wanting the calibrated FITS of some of my images since they contain data needed for their thesis. Kind of fun to be useful to those working on their Ph.D. That wouldn't happen if all I did was the common stuff. Apparently there's some communication between grad students as I get a surprising number of emails asking if I took and image of something at a certain time. Once in a while I have. Mostly though I haven't but add the object to the to-do list. Then there's the grad student in Turkey that seemed to think I'd have a galaxy at -66 degrees. Yes, he knew I was in Minnesota. Maybe he thought I used internet rental scopes. More likely he is desperate. Rick Stefan Lilge wrote: Rick, thanks for sending me the reprocessed version by email. Why not post it? It's better than mine, but I don't mind :-) Nobody will notice anyway, as nobody looks at "exotic" pitures. At least that's the case in the german board where I post my images, you get a lot of replies to the 200th "wide field Leo triplet" picture, but nobody seems to notice such small galaxies ;-) Stefan "Rick Johnson" schrieb im Newsbeitrag . com... Stefan Lilge wrote: I used two nights (March 4 and 6) for this image of NGC 3448 (Arp 205). The first night had some moonlight and only mediocre transparency, but good seeing. The second night had mediocre seeing but very good transparency, giving me a record background brightness of 19.0 magnitudes measured with SQM-L. A "normal" good night does have 18.7 mags around here. The difference of 0,3 mags does not appear to be a lot, but it meant a reduction of background brightness with this setup from about 8400 ADU to 6300 ADU. When I took this image I did not know that there is another galaxy (UGC 6016) to the right of NGC 3448 as this galaxy is not shown in Guide 8. I thought it was part of the tidal tail of NGC3448. When I searched for pictures of this object one of the few I found was made by Rick J. who's picture was deeper (of course). Taken from the middle of Berlin with a 10" Meade ACF scope at f/7.2 (AP reducer) on a G11 mount, SXV-H9 camera, 50x5 minutes for L, 12x5 for R and G plus 18x5 for B, colours with 2x2 binning. http://ccd-astronomy.de/temp3/3448colourgut.jpg Stefan Now this is one heck of a coincidence. I just finished reprocessing this one. I did this one before I really knew how to process images. Mine was very noisy and color way wrong. Also I'd so stretched the image to bring out the faint fuzzies and plumes I completely lost tha really wacky dust lane. I was quite shocked to see it appear in the reprocess. Now here it is in your image. I checked my image and my background was 526 which I consider high. I much prefer one of about 250 to 300. Not sure what made this one so "high". How you do so well under your skies simply amazes me. Rick -- Correct domain name is arvig and it is net not com. Prefix is correct. Third character is a zero rather than a capital "Oh". -- Correct domain name is arvig and it is net not com. Prefix is correct. Third character is a zero rather than a capital "Oh". |
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