Yooster

I've been imaging for a while with my WO Z73 and 294MM and 294MC cameras, on a CEM25P mount. I've had a lot of fun and learnt a lot in that time but feel I've now outgrown this scope and will probably be my next thing I'm looking to upgrade as I feel like I've started to get near the limit of what I can image to my satisfaction and my expectations naturally grow as I become more experienced. The biggest reason that I want to upgrade is due to star size and star bloat that I get with the Z73. To a degree I used to over expose a little but I have resolved that now and I think that characteristic is just inherent to it being a doublet. Yes I can reduce star size through processing but I'm at the point where I want to eliminate or reduce that in my workflow and start with smaller, tighter stars and perhaps resolve more detail that something like a triplet would hopefully provide. So I guess the question is, what options do I have, would like to stick with a refactor and within the weight limit of my CEM25P. Would welcome any recommendations to look at and consider rather than just splashing out cash on something that just looks nice! Ideally around the £1k - £2k mark I do like WO build quality, so the GT-81 to me is a likely option. Personally I'm not keen on the Redcats due to the helical focuser, as I use an EAF I'd rather have a rack and pinion style rather than messing around with belts. Other ones I've been looking at - Esprit 80 or 100, Sharpstar 76 or 94, Askar FRA400 (the latter I've seen some great shots with the 294MM)

Ah right cool yes the same one. Thanks, good to know. Think this is the one I'm going to go with

Which ones have you got?

Check out Star Adventurer or iOptron Skyguider Pro

Thanks both for your advice, very helpful

I was thinking one risk might have been that a new CEM25 would be coming out with improvements (like CEM vs CEM25P) but haven't found anything to suggest thats the case. I assume they will still be honouring warranties etc and at the end of the day if anything goes wrong there are a few independent people out there that can service and repair them. For me I'd set my heart on a CEM25P so could overlook those concerns. I still think surely they will fill the gap somehow, although usually manufacturers have the new model ready to go when the discontinue the old lines?

I've recently upgraded my OSC rig and there is a few filters I want to buy - Optolong L-Extreme, L-Pro etc My setup is a Zenithstar 73 II, Flat 73A and ASI294MC Pro. Eventually I would like a filter wheel especially if I upgrade to include a mono camera, but am aware I could fit the filter in the optical chain or a filter draw, or a manual filter wheel. Obviously 1.25" filters would save me a bit of money, but my question is, will I be at a disadvantage using 1.25" filters in terms if vignetting etc or any other reason to go for 2" over 1.25" ? I assume with the smaller 1.25" i need to have the filter as close to the sensor as possible to minimise any vignetting etc? I appreciate this can be corrected with flats etc.

yeah i noticed that. More expense!

Yeah sorry posted the wrong link, that one has been superseded by the below https://www.tracerpower.com/tracer-12v-24ah-lifepo4-battery-2.html

Looking to get a LiFePO4 power tank set up for my rig and can't really decide which is best. I appreciate compared to VRLA I'm going to be spending a lot more money but don't want to be spending more than about £250 My options are Celestron 13.2aH Powertank Pro £214 Tracer 24Ah https://www.tracerpower.com/tracer-12v-24ah-lifepo4-battery.html £249 Build my own Powertank I'd like enough capacity to be able to keep my rig going for at least 6 hours if not more - CEM25P, ASI294MC Pro, ASI120MM (Guide), Asiair Pro. I have a separate dew heater I can power from another battery pack for now. I've worked out that when mount tracking and cooling to say 20deg below ambient etc at most my load is about 2-2.5A @ 12V. I'm very much favouring LiFePO4 over VRLA for reasons of size, weight, voltage discharge cycle, safety, charge cycles etc. I don't want a big fancy thing with lots of lights and bells and whistles and likewise I don't want to spend £500 on a 60-80Ah model. I think I'm favouring the Tracer one as quite increased capacity for not much more than the Celestron one, anyone used these?

Luckily I managed to find one about three weeks ago, with Literoc tripod but no hard case which is what I wanted. I've since ordered a custom built case from these guys for about £100 https://www.theflightcasecompany.com/case-designer/carry-case (look great for many other uses as well and will probably order more for other gear) In honesty I presumed they must be replacing it as it creates quite a gap in the product range and I didn't want the expense for a CEM40 plus I wanted to keep it portable, so really didn't know what to do as I didn't want to order one then a new one comes out. In the end I didn't risk it and got one when I could from somewhere else. Find it hard to believe iOptron won't replace it.

Think mine is about three years old, the white/green one so not the original red. After seeing the videos I posted and opening mine up, its exactly the same issue on my mount. Definite QC issue. I think opening it up and cleaning/regreasing solved the 'progressive worsening' issue for me (which was a different issue), but just left the original problem still there, the clutch plate is not a precision machined item but a cast one with poor tolerances. If yours worked ok when you first got it, chances are its not this issue and just needs a good service.

Mine is exactly the same and from what I've read, there are quite a few of these mounts with the same problem. Some have no issues, seems to be a QC or batch issue The issue is the clutch plate, which is cast aluminium instead of machined. The central part is very slightly off centre and one side is raised. See https://www.youtube.com/watch?v=ublmCpZhuu4 and https://www.youtube.com/watch?v=FGHAh73QdIM Mine got progressively worse to the point balancing was not even possible it was so tight with the clutch loose. I opened it up myself, cleaned up, greased as best as I could. Resolved it somewhat but still 'sticks' on one part of the rotation. I was going to machine the affected part on a lathe as in this video however I've come to the decision to send it off dark frame optics to stellartune it. They will resolve this in addition to other mods and optimisations for £140. Of course, it goes without saying, you can really screw it up by opening it up yourself. But if its guarantee, send it back. I should add that mine was sticky on one part of the rotation out of the box from the factory. Just at that time, I didn't really know what I was doing so didn't really notice it as a defect.

Email received from FLO. I hope not, had my heart set on one.

Was looking to get a CEM25P but I gather iOptron have discontinued them. Anyone know if there is going to be a direct replacement for them or should I try and snap one of the few up remaining? I need portability and it fit the bill