inFINNity Deck

If you use a post-processing package like Astro Pixel Processor (APP), light pollution can be 'repaired' in that stage. I do not use a light pollution filter, but am pretty pleased with my LRGB images despite the Bortle 5-6 conditions: L : 120 x 60s R : 34 x 120s G : 34 x 120s B : 34 x 120s Nicolàs

Hi SiD, Would this help? ZWO ASI1600MM Pro Cool behind a SkyWatcher Esprit 150ED, ZWO ASI EFW with ZWO LRGB and NB filters, unguided imaging for 23 hours from Bortle 5-6 sky. Nicolàs

Hi Oldfort (that is not your real name, is it?), it looks like a single image am I correct (so not a stack)? Today seeing was not particularly great here across the pond in the Netherlands (Castricum, 340km from RMG as the crow flies). I took this image (with apologies for posting an image on your thread) at 09:46GMT with a SkyWatcher Esprit 150ED and ZWO ASI1600MM Pro Cool using a Baader ND5.0 foil filter. This is a 10 frames stack (false colour), but hardly any better than your image. Seeing was that poor that the limb looked like it was made of rubber, like what I see in your image. So best is to repeat at a day with better seeing. Nicolàs

Received the volume day before yesterday. Today I had some time to give it a quick look and I can only say it is worth every penny! The book starts with some stunning images, that good that you would almost lay the work aside as a work for professionals. Looking further it becomes clear that it is for the amateur astronomer in every sense. Various observation techniques and scopes are discussed and shown as well as several amateur home-made scopes. The physics of the Sun itself and behind imaging detail is discussed as well as the history of solar observations and the influence of our surrounding on seeing. Observational techniques from sketching to imaging and radio astronomy are discussed with ample examples. Processing is discussed in great detail using software we are all too familiar with: AutoStakkert, IMPPG and PhotoShop and techniques like deconvolution, unsharp mask, etc. are discussed. And even for those who are not interested in too much technicalities, the abundance of great images (most solar images in black & white, others in full colour) makes the book worth acquiring. The typesetting is clear as well with keywords and references to tables and figures in blue, so they stand out in the text. Perhaps there is only one downside: at A4-size and being a 1.7kg glossy paperback makes the book somewhat slack and unwieldy to handle. Personally I would have preferred a hard-cover edition, even if that would have added to the price. I am looking forward diving into it, so my advise: get yourself a copy as long as it is available! 😃 Nicolàs

Hi Nigella, nice images! What scope/filter/camera combination did you use to capture this AR2835? Nicolàs

Very nice again @Nigella Bryant! I love those full-discs you make, both in CaK and in H-alpha. Do you use flats for the full-disc images? If so, how do you make those? Nicolàs

Thanks for bringing that to our attention, just ordered a copy! Nicolàs

Hi Ceph, that detail came out pretty well, her is my full disc recording of that day, taken with a SkyWatcher Esprit 150ED: This one with a Lunt LS80THA in H-alpha shows the size of it: Here another one, taken that same day with a C11 in white-light: There is also an animation of that last one. Nicolàs

Hi Icosahedron, Impressive results! I presume you imaged it with the spectroheliograph you posted a while ago? The image quality has improved enormous since! 🙂 👍 Nicolàs

Last year I received a replacement blue filter from Bresser GmbH free of charge (which I believe is outstanding service!). While waiting for the new one I gave the old one a try with Acetic Acid (schoonmaakazijn in Dutch, it can be bought at the supermarket) to see if it can be cleaned with that as well. I soaked the filter in it for increasing longer periods of time (started with 5 minutes, then another 10, etc) and after four hours it is as new again, apart from a small spot on the edge, which most likely will not have a significant negative effect on the observations. Under magnification that small spot seems to have been etched by fungus. It now is my spare one in case the new one deteriorates as well (which I understood should not). Nicolàs

Hi ajohnson, I recognise these kind of uneven illuminated images from my LS80THA with pressure tuner. Although I am not sure what exactly causes it, the way the illumination appears can be influenced by shifting the imaged Sun to a different location on the imaging chip. I check this by slightly overexposing the sun, which nicely reveals how concentric the illumination is. Then I move it around until it looks pretty concentric, adjust the exposure to 90% and take the image. Nicolàs

Then here is the non-inverted animation from the Lunt images: Two additional recordings were made around the time of first and second contact. From these the first contact was found to be at 09:18:11UTC (theoretically, according to Stellarium for our location, this would have been 09:17:55UTC) with an uncertainty due to undulation of 1 second. The second contact was found to be at around 11:31:45UTC (theoretically 11:31:26UTC) with an uncertainty of 3 seconds. So on average Stellarium calculated the contact 17.5 seconds too early. I should mention in this respect that the observatory computer is automatically time-synched every 256 seconds using an internet NIST-server and that I determined the position of the observatory with professional GPS-equipment with centimetre accuracy. Nicolàs

Thanks Hughsie, Indeed quite a bit of work has gone into processing, more than those three hours needed to collect the data. This weekend I will add another time-lapse with the normal H-alpha data (so not inverted), just for the fun of it and to see if that looks nicer.😉 Nicolàs

Well... here is the white-light version: The Moon's limb clearly showing peaks and valleys. Forgot to mention in the first post that the first image of both animations was taken around 08:30UTC, the second at around 09:00UTC, all following frames 5 minutes later. Nicolàs

Today we were lucky to have splendid weather with good seeing and transparency. The observatory was running smoothly, with all four scopes pointed at the Sun: - Lunt LS80THA collecting H-alpha data every 5 minutes for 30s (2200 frames); - SkyWatcher Esprit 150ED with Baader ND5.0 foild collecting white-light data every 5 minutes for 20s (250 frames); - Celestron C11 EdgeHD with Baader ND5.0 foil filter and polarising eyepiece/diagonal-filter in combination with TeleVue Panoptic 41mm for observing; - Galilean type telescope with sketchboard for projection. Using the two imaging scopes I managed to collect 306Gb of data in three hours time. The H-alpha part has now been processed in IMPPG in inverted mode: On both the western and eastern limb two proms are shooting away, while the Moon passes along. Still to come are the normal mode and the white-light recordings. Nicolàs

Hi Steve, I take another approach, shooting 30s videos using FireCapture with the histogram 85-90% filled. Then stack some 25% in AS!3 and process the output with IMPPG. Finally I just slightly sharpen the output and give it a nice orange colour: So all is done in one single recording session: surface and proms. Nicolàs

Hoi Marfa, Welkom op SGL! Nicolàs

Hi Tristan, thanks for that info. The ND3.8 is indeed no longer available at sizes above A4. For that reason, and to be able to use it visually, I got myself the ND5.0 instead. My image was taken at 07:23UTC. I will give it another try as soon as the winds turn southerly as that should give me less hot air from surrounding rooftops. Nicolàs

Hi Tristan, very nice animation. Did you use ND5.0 or ND3.8 foil? From the Astrobin-page I learned you used a continuum filter as well. That morning I took the image shown below using a C11 EdgeHD, 4x PowerMate, ZWO ASi174MM, a green filter, and ND5.0 foil. It is not as sharp as yours though. Nicolàs

Last week I got myself a decent sheet of Baader ND5.0 solar filter foil (49x50cm). I had read on various fora that the ND5.0 foil was not suitable for solar imaging as it reduced exposure times too much, but the main purpose for the filter was observing. Of course I could not resist using it for imaging as well, just to see how far I could get with my first attempt. So this morning I gave it a try at 7:30am UTC. The imaging scope is my Celestron C11 EdgeHD. I used a green filter (have no continuum filter yet), a TeleVue 4x PowerMate and ZWO ASI174MM. Setting the camera to a gain of 300 resulted in 3.2ms exposures and a 66FPS frame-rate. Seeing was the greatest issue, but out of 10 SER-movies of 30s and 2000 frames each, 10 frames of one of them were good enough to stack. Nicolàs

These are my favourite, but start at £563 only: https://www.firstlightoptics.com/tele-vue-eyepieces/tele-vue-ethos-100-110-degree-eyepieces.html Nicolàs

Nice images John! Like Adrian, I too use Topaz Denoise AI for DSO with varying settings (here is an example, and here is another). It has indeed to be used with caution as it does make things up and can deform stars to elongated specks. For that reason I do not use it for all my DSO-images, it depends on how well Topaz handles them. The moon-images shown by John look very pleasing to the eye once run through Topaz, so I see no reason why it should not be used. I have also read comments that its use should be declared. I generally do so, but only to explain to other imagers how I get to my end result. I see no other reasons for declaring it, the images most of us produce are after all more art than science. Here in the Netherlands in 2019 I attended this presentation by Sara Wager explaining just that and I could not agree more with what she said. In general the scientific value of our images drops after the first non-linear stretch. After that it can at the most only be used to detect new or moving objects like novae, asteroids etc, or to show the distribution of gases, but not to take measurements of brightness, abundance, etc. As far as I have been able to tell so far Topaz only deforms structures, I have not seen it creating star-like objects. Nicolàs

Perhaps you could first give it a try with a screw extractor set? Nicolàs

Hi Gav, which of the methods did you use for the overlay? Nicolàs

Hi Gav, a quick calculation with a calculator: 31 (days in January) + 28 (February) + 31 (March) + 21 (today's date) = 111, so I used "day 110" from the animation (they are provided at 5 days intervals). If you want more precision, you either need to rotate the overlay slightly, do the calculations yourself (creating your own overlay), or use software like HelioViewer2. Nicolàs