Search found 253 matches
- Fri May 13, 2022 12:47 pm
- Forum: Image Processing Troubleshooting
- Topic: M13 star colors
- Replies: 11
- Views: 4054
Re: M13 star colors
Thanks for the effort, guys! I only have a moment this morning, so just the basic answers. Image was acquired with: 6" RC + AP ccdt67 reducer, at 993mm f/l QHY183C - note this camera has a UV/IR-cut window, so no additional filter was used pre-process in Siril, stacking with No Normalization Flats -...
- Fri May 13, 2022 12:27 am
- Forum: Image Processing Troubleshooting
- Topic: M13 star colors
- Replies: 11
- Views: 4054
M13 star colors
M13 is one of those objects where (I think!) there is a definitively correct color palette. For example, the image at https://science.nasa.gov/colors-and-magnitudes-m13 shows a mix of blue and reddish, along with spectral data supporting that. In my own M13 image: M13_g5o8_-10c_631x30s_90pct_sigma1....
- Mon Mar 14, 2022 6:57 pm
- Forum: General Discussion
- Topic: Combine data from slightly different telescopes?
- Replies: 9
- Views: 4163
Re: Combine data from slightly different telescopes?
I'm back with a variation on the same question.
Same telescope - RC6 with AP CCDTV67 reducer. I rearranged the optical train a bit, and wound up maybe a mm short compared to the spacing I had been using. The plate-solved focal length previously had been 877mm, last night was 894mm. OK to combine?
Same telescope - RC6 with AP CCDTV67 reducer. I rearranged the optical train a bit, and wound up maybe a mm short compared to the spacing I had been using. The plate-solved focal length previously had been 877mm, last night was 894mm. OK to combine?
- Wed Mar 02, 2022 2:12 am
- Forum: Image Processing Troubleshooting
- Topic: Frost
- Replies: 6
- Views: 2140
Re: Frost
I'll take "all in all a respectable image", and be happy.
I did use a bit of walking noise reduction. I still see some patterning at a 45° angle in the image, but maybe that's just over-active human pattern recognition.
I did use a bit of walking noise reduction. I still see some patterning at a 45° angle in the image, but maybe that's just over-active human pattern recognition.
- Tue Mar 01, 2022 3:42 am
- Forum: Image Processing Troubleshooting
- Topic: Frost
- Replies: 6
- Views: 2140
Re: Frost
Here's what I got as a first go. Looks like cranked-up aggressive wipe is doing its thing on the part of the stack with frost. Another 8 hours would help bring out the outer arms better, but I suppose that's why some people refuse to do broadband imaging from Bortle 7. A bit of walking noise, too, a...
- Mon Feb 28, 2022 11:26 pm
- Forum: Image Processing Troubleshooting
- Topic: Frost
- Replies: 6
- Views: 2140
Re: Frost
Thanks, Ivo. I obviously should have shot a special set of flats with the frost in place
I have learned that "RCs don't dew up" is a myth.
I have learned that "RCs don't dew up" is a myth.
- Mon Feb 28, 2022 8:58 pm
- Forum: Image Processing Troubleshooting
- Topic: Frost
- Replies: 6
- Views: 2140
Frost
I have 8 total hours of subs on NGC 2903 with a 6" RC. One night's worth - 3 hours of the 8 - I am pretty sure I had frost on the secondary mirror, because no set of flats produce what looks like a properly calibrated image. I have been playing around with various ways to take flats with this scope ...
- Mon Dec 13, 2021 2:10 am
- Forum: General Discussion
- Topic: Combine data from slightly different telescopes?
- Replies: 9
- Views: 4163
Re: Combine data from slightly different telescopes?
That helps! Not the answer I hoped for, but the one I expected. I am collecting OSC duo-band data, so I must choose between using the new scope vs gathering more data.
"more data" won tonight, but I doubt I will hold out too much longer.
"more data" won tonight, but I doubt I will hold out too much longer.
- Sun Dec 12, 2021 6:38 pm
- Forum: General Discussion
- Topic: Combine data from slightly different telescopes?
- Replies: 9
- Views: 4163
Combine data from slightly different telescopes?
I suspect I already know the answer to this, as I am aware that StarTools does not work well with mixing different exposure times, for example. I have been imaging with a WO Z61 doublet, and have acquired an AT65EDQ (triplet objective with integrated flattener). The 65 has a slightly longer f/l (420...
- Tue Aug 31, 2021 1:13 am
- Forum: General Discussion
- Topic: Combining OSC with Red only (Ha) from L-extreme
- Replies: 19
- Views: 7910
Re: Combining OSC with Red only (Ha) from L-extreme
Mine would be a Ha,Ha ;) And yes, this is a widefield view of the Cocoon, so a small fraction of the image is the Ha region, the rest is a rich star field. My understanding is that there is little-to-no Oii. I shot the L-extreme data under a full moon, so my thought was that including the G and B fr...