OK Apricot

@alacant the screenshot you've posted is when I was using the Evoguide 50ED - The log I posted for that was from Nov 2022 and I'm doubtful it's representative of last night. Please could you evaluate the log from last night with OAG? It's the first attachment if it helps?

@alacant The subframes themselves were fine from what I could tell with the preview. The image through the guide camera were, I thought, acceptable - There was some astigmatism/aberrations present but nothing like oblong or crescent shaped like I've read they can be. I've attached a guide log from both OAG and guide scope. I will try calibrating further north next time. I've been getting excellent results with a separate guide scope but the idea of the OAG is to save space and weight, and in theory more accurate guiding. I'll be taking a small rig to Vegas later this year so space and weight saving are important. @newbie alert As said above the idea of the OAG is to save space and weight on the mini rig I take abroad. I'm testing it on the 80ED because it's mostly galaxies I'd like to image for the next few months and this scope is the highest FL at my disposal! I didn't confirm in my original post, but the guide focal length was the first thing I'd changed before entering the ASIAIR. It has it down at 520mm with reducer after plate solving so I just copied that as my guide focal length. I didn't measure anything but to summarise, the process was this - Find focus with imaging camera and lock focuser, fiddle with OAG until focus achieved, double check focus of both cameras is close. The stars are perfectly acceptable with a little astigmatism present. If there is a guide assistant with the ASIAIR please could you point me in the right direction? According to Astro Tools CCD calculator the image scale of my 80ED/533 is 1.52"/px. Most of the time the guiding was slightly below that, but there were some excursions... @ONIKKINEN The sub frames, from what I could tell from the preview, were pretty decent - no obvious trailing - No readily visible difference in subs from guide scope to OAG. I don't think I have the software to measure FWHM, but from eyes it all looks pretty close. I've attached guide logs from separate scope to OAG. Thanks for the support so far chaps, much appreciated! So far the next things I'm going to try are to Bin2 and calibrate further north. I've attached guide logs - 07/02/23 is from last night with OAG, 23/11/22 with Evoguide 50ED. Same guide camera, same imaging scope, balance as close as I could get it. I don't know what to make of these logs so any education would be great! I've attached some snap shots for what it's worth. Thanks again guys PHD2_GuideLog_2023-02-07_194639.txt PHD2_GuideLog_2022-11-22_203308.txt

So this is at 520mm. I'm not sure how to provide a log from ASIAIR? As far as polar alignment I got it to 4" accuracy according to that. For starters I'll try bin2 next time.

I toyed with the idea of getting an OAG for a couple weeks and decided to just do it, thinking if it fails I can sell it and go back to a smaller guide scope. So it was delivered yesterday and last night I managed to get out to try to set it all up. After a couple of hours trial and error I managed to find mutual focus between both cameras, shout out to the moon 🙌. The setup: Skywatcher 80ED>0.85xFR>ZWO OAG(ASI120MM-Mini)>ZWO filter drawer>ASI533MC-PRO, controlled by ASIAIR Plus on an EQ6-R Pro. After finding rough focus I slewed to my target, fine tuned focus and set it off for calibration and to take some test shots. Backspacing of camera looks pretty close, no obvious aberrations on the sub frames (but will find out later tonight when I process the data). I was a little disheartened to see figures up near 2"RMS. I calibrated close to celestial equator and meridian (Thor's Helmet). Mount was balanced, tried 1,2,3s exposures, tried gain between 75-100, changed aggression, duration of RA/DEC but the best I could get was 1.3"ish average. A couple things I noted was when a plane flew through the guider Fov it was not to be seen on my sub frame, I'm assuming this is normal seeing as the prism is not in the line of sight of the sensor, so doesn't see the same thing. Also that DEC was reporting the highest error up around 1", RA around 0.8". I'm just wondering really whether this could've just been seeing, guiding showing higher error due to smaller image scale? Or could it be something else? I wasnt hoping for miracles to start with but was expecting a bit better than this seeing as the guiding software will show a good 0.4" on good nights with a guide scope.

First to mind for general stuff would be Cuiv the Lazy Geek. Very passionate and intelligent man and knows his stuff. Another for me would be James Lamb after I've watched a few videos on OAG - Thorough from start to finish. For wide field stuff I can't think of a better channel than Nico Carver's Nebula Photos.

I'm assuming the trouble comes from the focuser having to support the extra weight. I use the ASIAIR Plus so PA is done using the main camera. Also the C14 is but a dream. It would more realistically be an 8 or 925 😏

Ah OK, thanks chaps. The ZWO one is 8x8mm and the image circle from the Sharpstar reducer is 44mm. I image with the 533 so 11x11mm and guide with the 120MM mini - visualising it, I should be able to drop the prism fairly deep into the optical path without obstructing the imaging sensor, and I guess be more spoilt for choice for stars? It leaves me questioning the 80ED reducer - can't find much on image circle on that one, but again with the smallish sensor of the 533 in probably going to be alright, right?

I would say your improvement was down to the equipment but not nearly experienced enough to back it up with confidence! I feel like it would be simple enough finding common focus between the two cameras in daylight like you say, just the thought of potentially having to rotate everything to find a guide star puts me off. I have the 61EDPH II so the focuser and reducer have a rotator built in, but with a setup like this Reducer>OAG>Filter drawer>imaging camera I can't see how I'd rotate the OAG independent of the imaging camera. The C14 comment was a bit tongue in cheek - not in my lifetime 😂

I'm thinking of swapping to an OAG setup instead of a guide scope. Obviously lighter but seemingly more difficult to get going initially? Is it a PITA to swap between scopes? Would like to use on both my Sharpstar and 80ED, and part of my thinking is to get used to OAG for when the time comes to get a C14 👀. What about rotation? I may have to rotate the OAG to get a suitable guide star but then that might throw off my framing when it rotates the main camera with it. What were your experiences going from a scope to OAG? Its either this or a small 30mm jobby I think.

Evening all, Mrs Apricot and I are going back to Vegas in October, and this time I'd like to make the most of the skies nearby out there. We plan to hire a car, something rugged if we can like a Rav4 or similar so that we can drive out of town. We have booked it specifically around New Moon, temperatures will be comfotable, light pollution very low, and looking at Stellarium shows I'm spoilt for choice for targets. I'm planning on taking the mini rig - Sharpstar 61EDPH II, ASI533MC-Pro, Evoguide 50ED, ASI120MM-Mini, ZWO EAF and ASIAIR Plus. This will all fit into a carry on and I'm hoping to get priority boarding to cement a spot for my kit. Power wise, I'm still looking into it bearing in mind the airline limit of 100WH. I believe items like this also need to be carry on so size is a consideration. I have a plan B where I can power everything from a small inverter using the hire car battery. I digress... The mount needs to be portable and have goto, capable of 5min frames etc. So far I have two candidates - the Star Adventurer GTI and the AZ GTI. The SA GTi looks more purpose built for AP ready to go out of the box? The AZ looks like it would need some money spent on it and some modification to get it in the same ballpark, but there's no doubt it can produce results. Are there any other mounts out there that might fit the bill? Don't really want to spend more than £500 if I can help it, second hand market is an option if need be. So, what are your thoughts? Cheers 🙏

I recently had first light of my 61EDPH II with the California Nebula, and thought I'd have another crack at this target to do it some comparative justice to the 80ED. I absolutely love the Pleiades, one of my favourites! This is 60x180s with Darks, Flats and Dark Flats. 2" ZWO IR cut filter, ASI533MC-Pro, EQ6-R Pro, Evoguide 50ED/ASI120MM-Mini, ZWO EAF and ASIAIR Plus controlling the whole thing. Bortle 5-6, patches of thin high cloud, noticeably breezy but guiding absolutely fine at 0.6", probably not something I could've done with the 80ED. I've spent 7 hours to get to this point since getting home from work today 😂. I started with a normal stacking routine in DSS, sent it into PS and got to work. I wasn't really very happy with what I'd ended up with, with stars taking on that blocky shape, StarXT leaving things behind, so scrapped it and started again. This time I'd drizzled it x2 and followed a similar but more restrained approach - Much happier with the star shapes. Some curves, some masked curves, some RC Astro, some colour adjustments, some more RC Astro, a little more restraint and I have a result . I'm aware that the 61EDPH II definitely does not correct the blues very well, but at it's price point for a fast triplet, and considering the fact I may have exaggerated things during post processing, I'm going to bank this one as a successful capture from start to finish. Cheers! Edit - now I see it on my phone I'm not as enthused... I so need a new laptop 😭

I have neither the money nor the minerals to explore the idea of Pix yet 😅. I use DSS and Photoshop which I'm starting to get comfortable with, a consistent workflow and all that. It's on the cards for future though for an easier imitation hubble palette from OSC.

Thank you! @Richard_ it doesn't take much zooming before you see the stars take on a more blocky form. It would indeed take my 9MP image and make it 36MP, probably too much for my current laptop to handle 😂. That said I should be getting a new more powerful one soon.

I bought this lovely little scope from @Stu1smartcookie before christmas and this is the first real opportunity to image properly - I'd otherwise been out for a few tens of minutes since getting a filter drawer and 2" filters, testing for tilt, backspacing etc. All looks very well overall. I believe there is a degree of CA visible using IR cut, but I can take that. What a pukka little thing . 31x300s with darks, flats and dark flats. Tried to restrain myself during processing as I feel like I've recently been asking too much of the data that I gather. Sampling at 2.89"/pixel I could've probably drizzled this, no? Thanks for looking!

Got this beautiful Sharpstar 61EDPH II a couple weeks ago from a member of SGL. Finally got the reducer flattener today along with a number of other accessories, and got it fitted to the mount. Took it outside to test it all, so far so good. Love it 😍

I'm not a fan of the moon but had to give you a like for a funny post 😁. Visual stopped doing anything for me since taking up AP, but I must admit, I do regret, a little, selling the 127 Mak and eyepieces - it gave superb views of the moon.

Is this because of using a duo band filter? The master flat looked pretty uniform so I'm a bit confused here. Gradients I can for the most part deal with in post, but it would be nice to lessen the burden with some quality calibration frames. What should I do differently to get a more uniform result?

Absolutely this. That word infuriates me. How self important of a person to designate themselves that way, and think they have some sort of say in your life. They're sellouts and nothing more. I don't feel like any channel out there is any of the above really, closest thing to it being videos that have been sponsored... I don't like that, but meh I can handle it. My favourites are Trevor Jones (my Mrs calls him backyard Trev) Cuiv and Dylan Odonnell, though he's been very quiet 😒.

OK, so a short description of the stacking process - Uploaded 58 lights, master dark (20 of, couple months old), 30 flats (3.2s) and 30 dark flats. Kappa-sigma clipping of lights, median kappa-sigma for F/DF. These are just default settings, I've not played with these. Stacked 57 out of 58 light frames and went into photoshop. I wasn't quite sure how to respond to you saying to slightly overblow the image, so all I've done here is use levels and stretch until it's looking overblown. Whether or not it's helpful is another matter 😂. I've uploaded both the linear and overblown files. Hopefully they're of some use? I feel like the masterflat is telling me all is well and my flats are doing what they're supposed to be, but I just wanted to check with you more experienced folk. If anything else is needed, please let me know! Here is a single flat with histogram: Here is the masterflat: Overblown.tif Linear.tif

With just the flat/dark flat frames or everything (lights etc) as well?

OK so tonight's session has just finished. I took 30 flats and dark flats instead of 20 that I usually do. I completely forgot to take a screenshot so I will post up what they look like tomorrow. Do you need me to post just a single flat frame? Or do you need a master flat? Dark flat? Both stacked?

I'm not young to even pretend to have understood the above but I appreciate the time taken, thanks chaps. I'm going to try and make some sense of this. In the mean time, I will post up some flats on this thread that I will take tonight (if it's clear). A single flat and a master flat right? I just want to be sure I'm not making my images worse by applying bad calibration frames. Thanks once again 🙂

Hi ladies and gents, While not specifically reading our watching videos about flats, I've heard there may be an ideal exposure length, especially for cameras such as the ASI294MC-Pro. Is this true? The ASIAIR Plus will calculate the appropriate exposure length for flats depending on the light source, for me some of them being 0.8s, others closer to 10s. Is this going to produce usable flats or should I pay more attention to the histogram? Since I started applying flats to my stacks, I feel like my background of space turns out a lighter shade of black. It is most likely my processing but it could be anything. Please could I have a little theory behind this? It looks to be clear for a few hours tonight so useful testing time. Edit - I use a white screen on an ipad and a white t-shirt. Cheers!

Just my 2p... My work van was broken into just over a year ago. It had deadlocks, alarm, power tools in the back were even chained up and padlocked, and it was just outside my back gate. It was parked underneath a street light just off a main road. Those ***** even wheeled my black bin across my gate to block it. After that experience I've accepted that in the current social/criminal agenda, someone is always watching, someone always wants what you've got without earning it, and the police are not police any more. I wouldn't even dream of leaving my rig out unattended now, not even in a more secluded location. I wouldn't build an obsy either, draws too much attention. My solution was to get it in my head that if it's a clear night, I'm not getting any sleep! I will come home from work and try to have a few hours kip then go through the night. To avoid sitting in the freezing cold for hours, casting light onto my kit from indoors, disturbing the Mrs etc I bought a security camera. Nights imaging at home now go something like this... ... So I can keep eyes on at all times from all angles but remain relatively comfortable and quiet.

Went and got it myself... Thanks again @Stu1smartcookie, its a gorgeous little scope 😍