The Admiral

Thanks Sir Clear-Skies. I guess that more could be done to refine the image, but given the lack of data I didn't feel like committing more time to it, especially as it's a long while since I've used StarTools, and with the new version I'm certainly not up to speed. I don't use Photoshop. I'll have a look at ST 'isolate', though it'd be nice to retain some of the tidal dust; I'm not sure how that would be effected. Taken with Altair Wave 104 f/7 ED triplet scope, Photoline 0.79x reducer and Fuji X-T1 (effective FL 560mm). ISO1600. 90 x 60s lights, and 50 each of flat-darks, flats and bias. Stacked in AstroArt 6, processed in StarTools, and finished in Lightroom. Mounted on iOptron GEM45. Ian

A few nights ago I had another attempt at imaging with my new GEM45 mount. My target was the ubiquitous M51, and I have to say not the most successful of results. I found that I was getting a bit of star trailing with an exposure of 90s (could have been breeze induced I suppose), so I had to cut the exposure time down to 60s. Altogether a total of 90 minutes exposure. I've not been too discerning with processing as it didn't seem worth putting in extra effort. Needs a lot more data, and not as pleasing as my last attempt with M81/82. What surprised me a little though was number of other surrounding objects thrown up by Astronomy.net. In particular, IC4285, a spiral galaxy about a billion LY away, and moving away with a speed of 7.4% of the speed of light! The mind boggles . I've arrowed it in the main image. Ian

Thanks for posting that, a fascinating insight into remote telescope set up. Looking forward to seeing the datasets. Ian

You can find my initial experience on this mount here: https://stargazerslounge.com/topic/352386-some-thoughts-on-the-new-ioptron-gem45/?tab=comments#comment-3836371 Ian

I recently took delivery of this mount, having until now only used an Alt-Az mount for imaging. So this is a whole new experience, and as such I’m not really in a position to give a meaningful performance review. Nevertheless, here are my first thoughts. I wanted a mount that could be set up for each session, and light enough to allow my ageing frame to be able to carry it from inside the house to outside. It also had to be able to successfully carry a load currently around 6-7kg without complaint. So this is what attracted me to the GEM45. I bought the version with the case and tripod, non-EC. I don’t guide it as yet, so I can’t quote chapter and verse on its guiding performance. Here's the set up raring to go! I've left the tripod trousers on! First impressions. It seems a solidly built, well finished, precision machine, unlike what one would expect from a mass-produced object. The axes move smoothly and I haven’t noticed significant backlash either by ‘free play’ or other than instant response to commands when lining up objects. However nice the looks, performance is everything of course, though it does give confidence. The first thing I needed to do was to swap the latitude adjustment from the low position to the high position, as I live in the UK. It is worth noting that for where I live, ~51° N, I need to wind back the altitude to ~40° with the altitude adjuster (not re-set the setting from high to low, fortunately), each time I need to get the mount into the foam cut-out of the case. Initially I had trouble locating the bolts with which to bolt the mount onto the tripod, the Azi Locking Screws. Thanks to FLO that was simply resolved, but I found that one of the bolts was slightly bent, enough to bind a bit in the thread, again resolved by the excellent services of FLO. Also, these bolts are meant to be used with the provided washers, but only one could be located. These are little perishers, as it’s easy to drop them when assembling the mount, as I discovered. My wife’s eagle eyes managed to spot it on the patio; try doing that in the dark! It’s a pity that the bolts don’t have a winged- or star-head for finger tightening to make life easier with repeated setting up, but there isn’t room beside the mount to allow that. The bolt shown here is a make-shift arrangement and is not the proper bolt and washer. The same could be said for the Lat Locking Screws, since they have to be slackened off and re-tightened before and after setting up/Polar aligning. However, these could reasonably be replaced with hand operated bolts, rather than rely on the Allen key, as there is ample room. A note re. the tripod, is that it has an alloy top plate and I do wonder how resilient it will be to the repeated attachment of the mount. However, I also bought the Mini-Pier and the threads on this are inserts pressed into the alloy and look to be made of a more bolt friendly material. I plan to leave the Mini-Pier on the tripod. Tracking As I said I don’t guide so I can’t offer any figures. So the best I can do is provide some subs from my recent tests. You’ll need to bear with me on this as I’ve not many examples to date. My first examples are of M3 showing different sub durations of 90s, 120s and 150s. Unfortunately I was having trouble with my optical train and have got out of shape stars towards the edges anyway so that may confuse. Here they are for what they are worth: 90s 120s 150s. My second offering is a sub from an attempt at M81 shot at 90 seconds: The full image is posted here https://stargazerslounge.com/topic/352345-m81-m82-with-gem45-unguided/. In summary then: Pros The iPolar is a doddle to use, though does need a laptop to be set up for the alignment process, but that can be put away afterwards. Far better than kneeling on the floor and craning one’s neck. I’ve found tracking to be good enough for me up to about 1½ minutes, though possibly beyond that to 2 minutes or more, without guiding, with a FL of ~560mm and load between 6-7kg. Depends on how purist one wants to be about ‘round stars’. It’s quiet whilst tracking but slewing is by no means silent. I’m always concerned about disturbing neighbours so perhaps I’m being unduly critical. It’s quite difficult to judge how loud these things are in the middle of the night when you are standing next to the source. Then again, I’ve not used other mounts to compare it with. The hand controller seems fairly logical to use. Assuming I’m setting up everything correctly, I’ve found that the homing in on alignment stars to be somewhat ‘out’, and have always needed a significant correction to align. I do a 3-star align and I find this to be the case for each star. However, when I come to align on my target I found that it centred the object very well. May be I have significant cone error which will only be corrected for after the 3rd align, if I understand correctly. Cons The need to reset the altitude setting to around 40° in order to replace it into the case. Fiddly washers beneath the mounting bolts which are easy to lose. A touch of grease might help them to be retained by the bolt. Having to use the Allen key on the Lat Locking Screws. When aligning, the stars offered are in magnitude order, which from one point of view is logical, but is a bit of a pain when one wants to find particular stars. It would be good to be able to change your preference on star order. That's it for now, and I hope that it's been of some use. Ian

Thanks all. Yup that's it Paul, thanks. I'll take your word for that, I'm still trying to locate it . Ian

I'm just starting to get to grips with my new iOptron GEM45 EQ mount, having spent some time cutting my teeth in astro-imaging using an Nexstar Alt-Az mount. Very much an EQ virgin! I decided to image M81 & M82 as these were inaccessible with my old Nexstar, so it was new territory for me. I used my Altair Wave 104 f/7 ED triplet scope, Photoline 0.79x reducer and Fuji X-T1 (effective FL 560mm). ISO400. 60 x 90s lights and flats. I did take 20 darks but I found that using some old bias frames from an earlier session gave a better result. Stacked in AstroArt 6, processed in StarTools v1.6.393 RC2, and polished in Lightroom. I've yet to get to grips with this latest version of ST, so for this image I haven't used the full gamut of controls. I like to get as much detail as I can from my images, I don't do subtle! Fans of a naturalistic look may not approve . At about the 9 o'clock position there is a small blue 'smudge', enlarged here. It does unfortunately reveal some trouble with my stars! I had originally thought that this was NGC 2976, but Astronet shows that galaxy to be too far away. Anyone any idea? Thanks for looking. Ian

Sorry, can't confirm that. The photo came from a collection of the daughter of of the Director of the Observatory. Ian

Finally all my iOptron gear is here . Thanks, FLO! Ian

Good news! All good things come to those who wait :<) Ian

It was after last night's announcement, and my question was as a result of it . Sorry to hear that your business has closed though. The issue does seem a bit contentious though, with questions today over whether, for example, house building can continue. It all seems to depend on whether the "2m" rule can be satisfied. FLO seems to have got it sorted. Ian

See my post immediately above! Ian

Perhaps I'm being a bit thick, but why did you need the laptop out with your scope? Ian

Very nice too Brendan. You should be pleased with that. What sub length did you use? Ian

Thanks for your late evening clarification Steve, and good to know. Just so long as everyone keeps as safe as they can. We do appreciate what you are doing in this very difficult, and worsening, situation. Thanks again. Ian

New mount for me, but the shipment for the accessories I want are due at FLO tomorrow! We'll see, but I guess it'll take a while for FLO to find out what it's delivery companies' plans will be. Ian

Well having just heard the PM's announcement, where does that put FLO and its delivery companies? I guess all will be revealed as time unfolds. Sad but a necessary move. Ian

Well having just heard the PM's announcement, where does that put FLO and its delivery companies? I guess all will be revealed as time unfolds. Sad but a necessary move. Ian

In my case, exactly so, being denied my other interests! Well done for soldiering on and I hope that you all continue to remain well. Ian

For my sins I have one incoming, courtesy FLO, hopefully next week . Now I'm not in the habit of being an early adopter, it's not in my psyche, but given the self-imposed isolation I thought it would give me something to get my teeth into, even though we are heading towards the less favourable time of year for imaging. I needed an EQ mount that would take a 10kg load for imaging, but was light enough for my aging frame to carry from it's storage in the house and set up each time in the garden. I wasn't so keen on the CEM40 because of its geometry, as I am pretty much limited to southerly views. Don't expect a detailed critique though, as this is my first EQ mount and I've a lot to learn, having spent all my time so far imaging with an Alt-Az mount (ha-ha, Olly should be pleased to have another convert to what he would probably call a "proper" mount ). Wish me luck. Ian

I can't compare the standard Canon response to that of the Fuji, but I must say I've been very surprised and pleased with the red response of my Fuji XT-1, not withstanding the lack of astro utilites and the processing complications with the Fuji X-Trans filter array. I've used it with Alt-Az imaging which involves taking a lot of short subs, so conversion and storage has been important. I originally converted them all to DNG using the Adobe raw file converter, quick batch processing too. I now use AstroArt for the calibration and stacking. See https://stargazerslounge.com/gallery/image/31949-flame-and-horsehead-nebulae-ii/ That's 122 x 30s subs, but it could do with more! However, the XT100 has, as far as I am aware, a standard Bayer filter array, so shouldn't really present a problem so long as the RAF is recognised. If you use DSS, make sure that you are using the latest version. Ian

Thanks for the heads-up Dave, but you really ought to correct your web address Ian

It is a much cheaper alternative to Photoshop for general photography use, for which it appears to have found many friends. I don't use it for astro, but Nik Szymanek has an 'Imaging Masterclass' on using it in 'Asronomy Now', starting January. There was a similar question posted on this site recently. Do a search; there are quite a few threads. Ian

Amazing! Looking forward to seeing a mosaic covering the whole of the Orion region ;<) Ian