Jkulin

Hi Dave, I know my mate who has an ODK version designed by Peter Shah has dew heaters on the primary and secondary, he hasn't used them on the primary as he uses the extraction fans to draw air over the mirror and out of the rear, he does use a dew heater wrapped around the secondary. For my secondary I fitted a dew heater to the back of the secondary and then ran two copper strip across the vain and soldered the contacts, will save you quite a bit as well, I have no heaters on my primary: -

Here you go Dave, really very impressed https://ensoptical.co.uk/index.php?_route_=telescope-covers

Dave, I had my telegizmo 365 leak and flooded my mount, so as a precaution I bought one of Steve @ENS's breathable covers and I fitted that over my setup and then fitted the telegizmo over that, as an extra precaution. I was amazed that the Telegizmo doesn't have taped/welded seams and is just stitched...unbelievable, I used to design waterproof covers and we would never have put anything out without taped seams.

Looking at the example you posted, it would appear that either your guiding or Polar Alignment is off and the collimation. You have oval stars and dual diffraction spikes. I would address those issues first and see if your FWHM improves. HTH

Thanks Bob, I am back at the Hospital on Tuesday so will have to wait and see. The 10" has taken some thinking about and without my prior knowledge of the 8" it would have taken more thinking about, all set up for this evening so hopefully can get the Lum, Blue and the Green at least whilst we are moonless and then if push comes to shove can get the red and the Ha if there is a moon.

First light for this 10" RC on Wednesday night -6.1c, didn't feel that cold probably as no wind ?

Well first light last night was a true testing night and first light as I never expected it to go clear, but I figured at about 21:00 that it would be clear enough to get my focusing points, OAG focus and G2V subs collected. I have had the Scope over 6 weeks now and this was the first night that was clear enough to take advantage of. It was the first time checking that everything was working and the first fault was some weird foibles with the focuser, it appeared that the Cat5 cable I made up had a fault and therefore intermittently failed to control the Pegasus focuser, so I quickly grabbed a cat 5 cable that I had in my laptop case and sure enough everything was working beautifully after that. So first thing was to get the focus sorted so that i could then get the OAG in focus, by this time it was well after 01:00 in the morning and the temp recorded on my focuser was -6.1c but it didn't feel that cold. I was particular keen to see what the collimation was like and how well the secondary dew heater worked. Up until about 03:00 the seeing wasn't the best as there was still a few clouds passing over, but I managed a nice V curve with the luminance (thanks @RayD as your vids refreshed my memory on setting these up), but the RGB was not so lucky and I am really not sure why as the filters are parfocal being Chromas 50mm unmounted, and they had been fine with the Esprit 80 that I had first tested these on, so my only guess is the seeing unless anyone else has any thoughts? So you will have to excuse the messy cabling as I had to undo all of the cabling to check the cat5 cable. I used Sharp Cap for my Polar alignment and I have to admit it really is very good and IMHO far superior in speed and accuracy versus the Polemaster software. I never expected to be able to grab anything of a sequence last night, but was quite pleased with this 10 min sub screen grab of M51, to me it looks like there is no collimation errors to worry about or tilt, but I may end up eating my words when I do some proper captures hopefully at the weekend. I did grab a quick 5 min sub of M101 just to be sure and looking closely at the stars it really does look like the optics are spot on as is the guiding. I deliberately captured it offset as I wanted to see how flat the image was. So there you have it, hopefully we'll get finally some more clear skies and I can then put this 10" RC through its passes. All the best. NB BTW Bob, thanks for the good wishes, the Op was cancelled, was all in my gown and IV in and they cancelled because of health complications ? thus why I managed to do this as no spinal surgery!

I'm having major surgery on my spine next week and because of the atrocious weather I still had not had a chance to do any proper imaging, in fact I haven't done so since the 3rd week of October, I have never known such a long spell without proper clear nights ? Anyway, I thought whilst I can than I had better have a play with the balance points and ease of use of fitting the OTA onto the mount, as more often than not for the next 3-6 months I will be reliant on family and friends to slide it on and off as I will be forbidden to lift anything during the period. Now I'm about 5ft 10" and my pier is quite tall, deliberately so as I didn't want to be crouching under it for alignment and checking things, but I have to admit that even with a weak back, I had to use a bit of caution when sliding it on. I had drilled and mounted a 14" Losmandy bar, but as it turned out it was not needed and I have since reverted to the original 10" one that it came fitted with originally. My son is 6ft 2" and built like a proverbial brick house, so he will have no problem, my weedy mate who is a similar height to me and has a very strange resemblance to a bald twiggy (isn't that right Mark @Toxophilus) ? may have to go on a body building course...lol, nah it's not that bad, but I did fit it without the camera, filter wheel which saved a few kilos. Balancing was better than expected, I did need both 9.5kg weights and surprising the RA was fairly well balanced and will just need a minor adjustment because the rail has reverted to the original, the DEC will need a little more balancing, nothing that a few 25gm stainless steel washers can't resolve to counteract the focuser side, but otherwise I was quite impressed with the overall balance, it is a big beast though! When I finally get a chance to image with it, providing Mr Twiggy doesn't drop it then will post up first light: - There's a slim possibility of some imaging on Sunday, but not with LRGB as we are fast approaching a full moon, so will stick to NB

For that very reason I have reverted to using a separate guide scope. I can achieve back focus using the Moravian OAG/FW and Camera, but the Moravian OAG is not very good in my opinion instead I am using the Celestron, but it is very long. For my RC's then I will use an OAG but there again I don't have a back focus issue. Please make sure that when you make your measurements with the Esprit that you take the distance from the CCD to the shoulder of the flattener which must not exceed 55mm, however when you add a a 3mm filter then you need to add 1mm and a 2mm filter you need to add 0.6mm. The 62mm is only if you choose not to use the field flattener flange adapter. It's not very clear in the manual, but essentially its 55mm CCD to the Flange and 62mm CCD to the back of the flattener with no adapter fitted. I am not aware of any narrow OAG that you could use instead.

Hi Mihai, I've attached a pdf showing the backfocus of the AP reducer which they claim is 85mm, my train should just about accommodate it, the distance from my CCD to the front of my FW is 33.5mm, so with the backfocus at 85mm I have 51.5mm to play with, which should be just about perfect as long as my OAG is in front of the FR. With 250mm being the total distance, then I shoudln't have any problems fitting it all in. Teleskop-Express Astro Physics CCDT67 067x Reducer 2 - eg for GSO RC.pdf

Thanks Graham, I don't plan on messing around with the FR until I have got it working perfectly without and with a nice V Curve and the Step Size and Focusing points calculated. Do you think my back plate is the built in tilt plate or is it just for collimation of the primary?

Hi Steve, If ever you are over my way, stop in for a coffee and you are welcome to have a play with it to see if it suits your needs. Yeah I know about the interior, it's fairly tough and once they had a seatbelt around them they didn't move around much ? Thanks for your kind words about Storm, one minute he was here with nothing visibly wrong and the next day a brain tumour and we had to say goodbye?, he was a legend, not once did he ever lift his leg against my pier, used to talk to us and tell us when he wanted something and especially told us when he didn't want to get off the settee or drop a rotten apple in the garden, raw is an understatement, so trying to keep my mind busy, AP has helped keep my mind occupied.

Owning two RC's certainly was more viable for my wallet that many of the high quality branded RC's out there, it will probably be a while before I use it as currently my targets needed a wider FOV, so I doubt it will be used until February. GSO have certainly been pushing their range for a number of years, I looked and searched on Astrobin as the quality and number of images taken with GSO RC's and it really was a considerable number, which influenced my buying decision.

Hi Graham, Just took a photo and I think my one does have the built in tilt plate: - Mine came with 2 x 1" Spacers and 1 x 2" Spacer, I reckon I should be able to achieve focus by removing the 1" Spacer and extending the focuser out by an additional 1/2" but won't know for sure when I will get some clear nights to play. Wishing you a Very Merry Clear Christmas.

Hi Graham, funny you should ask that, my mate came round to look at it this afternoon and he said was I aware that it had the built in tilt plate, which I thought was the collimation adjustments for the primary, then I remembered that the primary is fixed so accepted that it must be the built in tilt plate. When I get a chance I take some more images and post them up. It certainly is back heavy especially when I connect my camera and FW, but that should be easily resolved when I fit the 14" Losmandy rail and attached the clamp with the weights fitted to it, rather like my 8" Carbon RC: -

Thanks Bob, and a Very Happy Christmas to you as well. How are you getting on with the 120, hopefully good?

Thank-you Jeremy and the same to you and your family

I have been surprisingly impressed with my Carbon Tubed 8" F8 RC to convince me to start looking at the 10" Truss Model for deep sky. I originally wanted one of Peter Shah's 656imaging (http://656imaging.co.uk/) DK Scopes as they are a thing of beauty, but having recently bought the iOptron Mount, Moravian Camera, FW and OAG and the Chroma 3nm filters, the cupboard was almost bare. Well you can always find money when something comes up and in this instance the credit card took a partial bashing, Ian at Altair Astro sourced me one of the GSO OTA's re-badged as theirs. I have always found it a pleasure to deal with Ian, he's a small outfit that genuinely cares and I decided rather than risk the OTA getting bashed around with the Christmas couriers that I would take the 199 mile drive over to Ian's place, even though I knew that it is one of the worst drives for me, it's cross country and after Kettering is single garage way, 4 hours later I arrived at this delightful village in Aylsham, Near Norwich. When I arrived I was amazed how Ian managed to get so much stock into this little historic shop, it was crammed to the ceiling with products, Ian as always stopped everything he was doing and we finally got around to sorting the payment and the dilemma as to how we were going to get this massive box (85cmx50cmx50cm), into my 911, which I had purposely driven, as it's more economical than my other cars and through the winding lanes is a bit of fun. As a 2+2 is does have rear seats, which are OK if you are a child or as can be seen when I had my 2 boxers (Sadly Storm the bigun passed away last month and I'm still raw?) so I figured that I could put the OTA behind me and break the box down and use that for cushioning, Ian suggested that I take the OTA and all the bits that came with it and he would send the empty box to my home, I gratefully accepted Ian's suggestion, and I then pulled up outside his shop in a narrow high street, dropped the roof down and Ian very kindly lifted the new RC into the back of my car, as I am about to have major surgery on my spine and didn't want to cause more damage. Well now to the RC, technical specs are below, this is the MKII version and it is beautifully made, with rich carbon fibre construction and the attention to detail is truly awesome. Aperture (mm) 254 Aperture ratio (f/) 8 tube diameter (mm) 420 Tube weight (kg) 15,2 Tube construction Truss Tube Tube length (mm) 735 Tube material Carbon Type Reflector Coating multiple Resolving capacity 0,45 Type of build Ritchey-Chretien Focal length (mm) 2000 Limit value (mag) 13,8 Light gathering capacity 1320 Max. useful magnification 508 Reflector reflectivity 99 Secondary mirror diameter (mm) 112 Ventilation for central mirror yes Secondary mirror material Quartz Main mirror´s construction hyperbolic Primary mirror - Material Quartz Focuser Connection ( to eyepiece) 3 Type of build Monorail Gear reduction 1:10 Fine movement https://www.astroshop.eu/telescopes/gso-ritchey-chretien-rc-254-2000-carbon-ota/p,47237#tab_bar_1_select I had decided to go for the 10" 2000mm FL as I had an unused Astro Physics 0.67 Focal Reducer, that I could use to drop it down to 1340mm F5.3, and with my Moravian G2-8300 would give me 0.87arcsec/px rather than the 0.59arcsec/px. The focuser was the only weak spot with any of the GSO RC range of scopes, being a Crayford as well meant that I wanted to change it and rather than compromise, I went for the 3" Feathertouch R&P and added a Pegasus Motor Focuser as I am really impressed with the lads at Pegasus and Ian is the main UK stockist so I knew he would have one in stock. Ian also supplied a 14" Losmandy plate as I knew that the iOptron CEM60EC was quite critical with balancing and therefore if need be I would change the existing 10" one to the longer version and then I could slide a Losmandy clamp with extra weights on the front for balancing. Being a truss design, it came with a Shroud. There was also 3 fans behind the primary to extract air and reduce dew on the primary, supplied as well was a Kendrick style dew heater for the secondary, which fastened with a few dobs of silicone on to the rear mirror. now usually owners run the cables over the top of the vanes, but I had a better idea, that I intended to use and afterwards I saw that someone else had adopted this idea on here. I had purchased some very thin copper strip, which stuck really firmly on the side of the vanes, I soldered the leads from the dew heater at one end and secured the main feed to the other, then painted with blackboard paint and voila you can hardly see it. I then made up a Cat 5 cable to provide control and the power to the focuser, this focuser is brilliant and for under £100 is far cheaper than anything on the market and has a really tidy appearance rather than the ugly lakeside motors that I have on one of my other OTA's, no more untidy multiple cable to the motor and it kept everything so much simpler. I mounted the Pegasus UPB on the top as I figured rather than my usual trick of fitting extensions under the Losmandy and having everything concealed under there that it might cause greater top heaviness, which moved everything higher by 40mm. I tidied up all the cables, I need to tidy the power feed to the fans, but that isn't urgent and will be done waiting for the new Galaxy Season, I doubt if I will get to use it yet as there are too many nebula targets queuing up to image due to the terrible clear skies we have been having for the last 10 weeks...it might go on even further with the purchase of all this new kit...sorry ? All the best everyone and Have a Merry Christmas.

Yep just rotate the "Captains Wheel" and it will separate. Its not rocket science and really is very simple.

Thanks for sharing, what is the background thunder sounds, is that part of the Aurora?

Might be best if you save it as an .mp4 or .wmv file

This is mine now and its rock solid

Steve send @peter shah a message as he shoots widefield with a Sony and might be able to help you.

Steve, The back focus is the critical thing so 55mm from your CCD to the face plate of the Esprit field flattener, you will need that if you buy the scope. Remember to add extra for filters etc. You will need to see if any of the photographic retails make a Sony T2-Adapter, if not then you'll need to obtain a Sony>Nikon or Sony>Canon adapter and then you can use a proprietary T adapter to the Esprit, but watch your back focus as you really need to identify the CCD distances of your Sony. I had to to do similar for my Leica, with a Leica to Nikon and then a Nikon T-Adapter. Hope that helps?

Yep mine were a perfect fit, someone was selling a set of Williams ones on here, just remember to check whether the hole spacing is metric or imperial, the Williams was metric so I needed a metric spaced Losmandy bar. On the top I had a SW Guide Mount setup, but took it off as I had planned to use my Moravian OAG on all three setups, but may revert back and just use the OAG on the RC. I cannot for the life of me see why SW made such a poor setup, after all its fitted with a really good R&P focuser, quality optics but crap attachment to your mount.?