| Would you be interested in contributing towards an AB all sky survey? | |
|---|---|
| No. I wouldn't find such a survey useful. | |
| No. Satisfactory data already exists for me elsewhere. | |
| No. I would find such a survey useful, but I don't have the time, location or equipment to contribute. | |
| Yes, I would be interested in taking part. One or two fields maximum. | |
| Yes, I would be interested in taking part. Prepared to do multiple fields. | |
| Login to vote and view results. |
16.52
#...
·
·
9
likes
|
|---|
|
Dear AB friends, Increasingly I am struck by the depth and beauty of some of the wide-field images posted here on Astrobin. I find myself increasingly using some of these images - including those I have generated myself - to act as a substitute sky atlas to find objects for follow-up study. This led me to thinking whether AB users could work together to produce an atlas of the sky that would be of general use to everyone. Now AB is an incredibly valuable resource with many hundreds of thousand images already, but I am not sure it it has the uniformity, homogeneity and completeness that would characterise a true survey. I may be wrong in this assumption, and I would be happy to be corrected below. [The wonderful heat map of image centres on AB does suggest that the entire sky is well covered with images here, but the real question is how uniform is the image data] There are many other surveys out there, but none designed specifically for those of us looking for nightly targets. I use telescopius and the DSS, but the reproduction and uniformity still make in sub-optimal (at least for me). And none to my knowledge that has such a crowd-sourced origin, which I think it kind of cool. Not to say potentially good promotion for AB. [I am also writing this in the shadow of the IP theft discussion, and I really wanted to spotlight the potential for good the internet, particularly this community, has.] Having been a professional astronomer, associated with a number of surveys I noted down what I would want from a survey design to maximise its usefulness with the bracketed values initial suggestions] 1) Regular field centres, with 10-20% overlap. [10degree field centres, 15x15 degree areas, mosaicing likely to be required ] 2) Uniform pixel scale [10arcsec/pix] 3) Uniform passband/colour [RGB or OSC] 4) Uniform depth and image quality. [SNR=60 at 22.5mag/arcsec^2, standard PI WBPP processing pipeline with SPCC and BXT/NXT] Since the sky just over 40000 square degrees, then field centres spaced 10 degrees apart would result in a survey of just over 400 separate areas., with individual fields being 12 x 12 deg in size. To some extent, this is tailored to the type of survey equipment that appears to be quite common on AB - the fast 135mm telephoto camera lens. Such an area could be covered in two overlapping panes using a full frame sensor or four x APSC size at a scale of 10arcsec/pixel. Longer focal lengths up to 200mm would also be suitable (more mosaicing required, and some binning up) and down to 100mm (no or little mosaicing - but possibly some drizzling) The passband would initially be broadband - achieved either through LRGB or OSC. Uniformity will be crucial. Although I would not propose to make a mega-mosaic about of all the fields, people would need achieve a degree of uniformity over the panes contributing to their individually mosaiced frame. Clearly there are many out there who can do this brilliantly well, but until recently I struggled. However, I do find that with the new PI WBPP processing script including local normalisation and autocrop, plus SPCC and the RC Astro Blur/Noise Xterminator tools, I can get good uniformity between moscalced panels. Then there is the issue of depth, and the one I am the most unsure about. In a Bortle 2 sky with an f/2 system, I can get to a SNR of around 90 at 10arcsec/px for 22.5mag/arcsec in 2.5hours. This is deep - and possibly overkill. I would be interested to hear from those who might want to take part, just what a realistic limit should be. It will depend of typical camera speeds and night sky brightness, and probably should be two much more than 3 hours per panel. Given this wonderful confluence between hardware and software, I do think the time is right to attempt something like this as a new generation of community sourced astro-photography atlas. But it needs people to do it. At over 400 fields [field centres would be distributed randomly to volunteers based on latitude, with the poles perhaps needing some special attention]., this survey would need a few volunteers. Even if people were to do more than one patch, I don't think it feasible to do with less than 100 volunteers. And take a couple of years. Are there then many people out there with the right kit, right skies and inclination to spend a night or two imaging a random bit of the sky for the "greater good". I don't know. And finally there is a question of workload. It is a huge job to coordinate, but I am happy to stick my hand up. Having said that, it will rely at lot on individual contributors to take processing a significant way [to the end of the linear processing regime?] following a largely prescribed pipeline. [PI being the most obvious, simply because of the number of users]. The poll included with this note might help assess whether this idea is just unnecessary, stupid, crazy or possible. Note that responses are just to assess feasibility, you are not signing up to anything yet! Comments on the survey design parameters would also be welcome. Clear skies! Brian |
1.20
#...
·
|
|---|
| Interesting idea. I would contribute a bit when a clear night finally comes around again. Dang UK skies! |
7.90
#...
·
·
1
like
|
|---|
| I most likely don't have the kind of skies except maybe in the far galactic north but I can contribute with remote telescope time. |
3.77
#...
·
·
1
like
|
|---|
Brian Boyle: Could you explain how other AstroBin users can determine the SNR for a given magnitude in their own data? |
3.87
#...
·
|
|---|
Victor Van Puyenbroeck:Brian Boyle: Yes, I’d like to check some of my wide FF data to see how much integration would be needed for my location and gear. |
11.64
#...
·
·
1
like
|
|---|
| Interesting idea. I did not join the poll, as none of them accurately reflects my situation. But I definitely support this. Once you start, I will either join myself, or bring others (who are not on AB yet) to help. |
3.81
#...
·
·
1
like
|
|---|
| @Brian Boyle I think it's a great idea. I was wondering the other day if there could be some background service behind AB that compiled all our raw data into some massive survey. I've been thinking a lot about how we all store raw data generally (all local, private, hopefully backed up but often not, etc) I've been storing a solid portion of my data in aws S3 and using a hosted server to do integration. If calibrated frames were what we collected, would be more advantageous in stardarization? Obviously the dataset would be much larger but maybe that mitigates other issues with uniformity? In terms of usage, how do you foresee the end product? planetarium style browsing and panning? or more targeted selection of a pane and review? Have you ever used the Framing Assistant in Nina? https://nighttime-imaging.eu/docs/master/site/tabs/framing/ Do you picture this survey being something similar but much higher resolution? sorry, lots of questions. Just wanted to keep the brainstorm going |
|
16.52
#...
·
·
1
like
|
|---|
|
Thanks for all the replies so far. A great response, and 90% of respondents to date would find it useful or want to take part. In regards of SNR, I calculate it from first principles using the flux of Vega above the atmosphere and the known efficiencies of the various parts of my optical train. I check the calculated counts against known sky brightness and aperture photometry around a few unsaturated stars. A bit cumbersome, I am afraid - but it appears to work. @Nick Grundy Great questions on the curation. It is the one area, I didn't touch. I was thinking more a targeted selection of pane and then review. I cant imagine the programming involved browsing and panning the whole sky. The latter might also cause seams - which reduce the usefulness of the DSS in Telescopius - at least to me. Note that I am not a programmer. Last I semi-seriously wrote was the back mid-90s and that was in Fortran 77 and Unix command line... But as a collaboration I am sure we can find someone. And I think you are spot on to highlight it as something we need to consider from the outset, balancing usefulness with effort. Heck, I was thinking we might even wan't to publish a book. With the 15x15 deg images on one side and an annotated version of same on the other. Might be a limited print run through..... Keep the comments coming. They are great. So far we have 5 people interested in doing multiple fields and 8 interested in doing 1-2 fields 5 x 4 (say) + 8 x 1.5 + @Wei-Hao Wang army of vounteersand we could be over 10% of the way there already. CS Brian |
0.00
#...
·
|
|---|
| Interested! |
2.11
#...
·
|
|---|
|
I would love to contribute - and answered yes in the poll. But I realize that I fall short in terms of equipment as my current only focal length is 1000mm 😉 |
|
2.11
#...
·
·
2
likes
|
|---|
|
A thought here ☝️ @astrobiscuit running the BAT (Big Amateur Telescope https://www.astrobiscuit.com/big-amateur-telescope) maybe he/they have some experience to share about data collection, integration etc. 🤷♂️ @Big_Amateur_Telescope |
|
16.52
#...
·
|
|---|
Christian Bennich: Thats really interesting - this proposal is sort of an inverse BAT. Is astrobiscuit on astrobin? |
|
16.52
#...
·
·
1
like
|
|---|
Christian Bennich: You might have to do a few mosaic panels! CS Brian |
|
2.11
#...
·
·
1
like
|
|---|
Brian Boyle:Christian Bennich: Yes, edited my original post with the AB usernames of astrobisquit and the BAT |
1.20
#...
·
·
1
like
|
|---|
| Happy to help. I’d be particularly interested in tackling the south polar region - a bit of a passion of mine! |
|
0.00
#...
·
·
1
like
|
|---|
|
I just came across this thread and think it is a really great idea. Recently, I also ran into the issue of lacking high quality survey data for planning of images. Because of my sky conditions and lack of equipment for this project, I won't be able to contribute data, but I am willing to contribute in the planning-phase and processing of the images. I think the preprocessing must follow a certain standard, that has to be well-defined, so everyone will be able to follow it. Regarding the issue of how to public the survey data, I would find an implementation into a stellarium survey the most helpful, as I always use that for my image planning and I think a lot of others too. However, I don't know the technical aspects of such an implementation. What may be of interest for this project is the MDW Surves: https://www.mdwskysurvey.org/ They are doing a similar project with H Alpha data. Maybe they are willing to provide some insights of the planning, if we need some help? CS Gerrit |
|
2.11
#...
·
|
|---|
Brian Boyle:Christian Bennich: If that could work - count me in. Camera update incoming for better imaging soon 🤪 |
|
16.52
#...
·
|
|---|
James Tickner: *** James, I was really hoping that someone (actually two someones!) would put their hand for the polar region. With approx 20% of AB users in the South, a volunteer for the South Polar region is worth their weight in gold. Thank you. Brian |
|
16.52
#...
·
|
|---|
I just came across this thread and think it is a really great idea. Recently, I also ran into the issue of lacking high quality survey data for planning of images. Hi Gerrit, Thats great. And just what the project needs. Your experience Agree on the standardisation of the processing. My own [linear] workflow for wide-field mosaics is For each pane: PixInsight WBPP (with LN) -> ABE (1st order) -> SPCC - > Blur Xterminator [0.1 stellar reduction] -> Noise Exterminator I then combine panes in AstroPixelProcessor, as I haven't yet been able to achieve success with PI's mosaicing programs [any of them!]. [Waiting for Russel Cronan to come up with Seam Xterminator!] As to survey design, I know a little bit about it. In my professional career, I was Director of the Anglo Australian Telescope which oversaw the UKST sky surveys (including Ha) and the spectroscopic survey programs 2dF, 6dF and RAVE. I also led the 2dF quasar survey team. Later on, I led the construction of the Australian SKA pathfinder (a radio survey telescope). In all these things, I wasn't really the do'er, more the driver (my programming skills stopped 30 years ago with Fortran77 and the Unix command line), but I understand the high level stuff pretty well. Nevertheless, one we have established the basic feasibility, I think we should reach out to as many survey groups as possible, as one can always learn so much from contemporary experience. CS Brian |
10.80
#...
·
·
1
like
|
|---|
|
I would have loved to help… Sounds like a great project but I don’t have the right gear with my 750mm refractor and with my location (bortle 6) it wouldn’t really work either… if you ever decide you need more zoomed in detailed shots of certain objects from the southern hemisphere in NB to include in this happy to help in anyway I can. what would be great regardless is for Astrobin to implement a way to visualize all data taken by its member on a sky map. Steeve |
|
3.87
#...
·
·
1
like
|
|---|
| I don’t think you’re going to have an issue with the North polar region, I live at 44*N and am a ways south of the forum members from England or Western Canada. Although I am about as far north as you want to be if you hope to image between late May and the end of July. Even my nights get down to 3 hours of astronomical darkness. |
|
16.52
#...
·
|
|---|
Joe Linington: Hi Joe, I was think that imaged at the pole can be a bit tricky - my mount wont sync position with the ASIAir for declinations closer than 5degrees to the pole. I also know that -90 was a real challenge for the UK Schmidt Sky survey. But times change, and it may be that imaged (and tracking at the poles is straightforward for most poeple. |
|
3.87
#...
·
·
1
like
|
|---|
Brian Boyle:Joe Linington: Use a guide scope, not an OAG and turn it 45* off the axis. The only catch is you have to stop and manually perform the merdian flip and re-calibrate PHD. Using APP, I could literally manually point anywhere with Polaris in the frame and repeat over a few nights and APP would stack it all. |
1.91
#...
·
·
2
likes
|
|---|
|
At 43S, I have a Bortle 6/7 sky in my backyard and Bortle 2/3 site within an hour drive. I don't like voting no but all I have to offer is a 600mm F4 lens slapped onto an astro DSLR. Can we really not make use of my setup? And side question, finding images in R, B or Ha isn't too hard but I always feel that in OIII there isn't much out there (FYI, I used sky-map for a while and much prefer ESASky for the variety of data sources). May be a NB survey primarily focusing on OIII could help our most dedicated "faint nebula hunters" in increasing the size of their own catalogues?  |
|
16.52
#...
·
|
|---|
Joe Linington:Brian Boyle:Joe Linington: Very smart! |
