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Everything posted by ollypenrice
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Ovoids with Mesu and Tak FSQ 85
ollypenrice replied to gnomus's topic in Imaging - Image Processing, Help and Techniques
Nor do I. I host a robotic FSQ85 which did a recent first light and, with an 8300 chip, the corner stars were not perfect, they were elongated radially from the centre a tiny bit. A pixel peeper would have been disgruntled (and in view of the price one can understand that!) but I'm a pragmatic imager and I'd have bought that scope and camera for my own use. It wasn't far from perfect and I think you'd be taking a risk in swapping it for something else in its class. Yours is far worse and I would not accept it. I do think Takahashi have a problem with the Baby Q. As an aside, I now use a couple of old FSQ106N fluorites, mine and Tom's, worth about £2K a pop and they have no trouble at all with full frame sensors. Quite a bit cheaper than a new Baby Q.... Olly -
Ovoids with Mesu and Tak FSQ 85
ollypenrice replied to gnomus's topic in Imaging - Image Processing, Help and Techniques
Without doubt. Olly -
Just a further comment on two posters above. Pieter was too modest to say that he is an expert mechanical engineer and Steve was too modest to say that he wrote yet another bible, this time on how to live happily with SiTech! Olly
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Thoughts on which imaging rigs to concentrate on
ollypenrice replied to Gina's topic in Imaging - Discussion
It's the multi rig that really does the business for us. That's the dual Tak. The TEC is a luxury on the side but the multi rig is fast... Now, sure, I personally have lots of clear skies here but the guests who come for just a week have just a week. The tandem is the thing. I counsel... multi-scoping! Olly -
Elephant-Trunk-Flying-Bat-Nebulae-HA-Nikkor-ED180.jpg
ollypenrice commented on RichLD's gallery image in Member's Album
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As I said above, I think Takahashi are overly optimistic in the flat field claims they make for the FSQ85. There does seem to variability from instrument to instrument, too. I used mine with a 15mm sqyuare chip and had excellent results but I think Takahshi should be brought to book over their field size claims. This has been much discussed on here. Olly
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One of my guests uses a Berelebach wooden tripod for his mobile Mesu. It seems to work superbly but I'm not sure which model it is. https://www.berlebach.de/?bereich=firma&sprache=english His website is here: https://pietervandevelde.smugmug.com/ In terms of quality of construction and performance the Mesu is in an entirely different class to the EQ8. Have you seen this video? (Sorry, the quotation system on the new forum still won't play nicely for me so you'll need to scroll up from here to the top of the thread.) It gives a good insight into the EQ8. At the risk of repeating myself, the Mesu I share with Tom O'Donoghue has still to drop a sub to guiding error of its own. We have dropped a few due to faulty guide camera cables but you can't blame the mount for that. In terms of its fit and finish it looks like new, being made of first class materials throughout. I'm one of the few astrophotographers who can say that his mount is the most reliable bit of kit in his observatory. Olly
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Ah, I misread the chip dimensions. My apologies. Olly
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27x34mm is pretty big. I wonder if the FSQ85 will give distortion free stars at this size? Both Yves Van den Broek and I found that it was nowhere near covering the 11000 chip without distortion. I know Tak claim it will cover 35mm format but - well - I think it may be a rather wild claim. Are your filters 2 inch mounted or unmounted? We use both in our dual rig. The vignetting is certainly more severe with the mounted set but both are workable on the full frame Kodaks and FSQ106. Olly
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Hydrogen Alpha and Beta filters
ollypenrice replied to John in Penzance's topic in Getting Started With Imaging
For an imager the H beta line traces pretty much the same gasses and structures as the H alpha but with a fraction of the signal. Is it worth it? Why not add a touch of Ha to the blue channel as surrogate H beta? Many do. But for visual hunters of the Horse then our eyes can see H beta and so this filter can pass just enough of the emission to render the dusty HH visible by contrast. Yes well - I reckon I've 'seen' it three times in our 20 inch Dob but I'm using the word 'seen' in a rather optimistic way!! Olly -
Show us your dual scope set ups
ollypenrice replied to spaceboy's topic in Discussions - Scopes / Whole setups
Ah yes, you'd mentioned the FLO devices but I'd forgotten. It's too hot to think at the moment!!! Olly -
Show us your dual scope set ups
ollypenrice replied to spaceboy's topic in Discussions - Scopes / Whole setups
That, my dear fellow, is the definitive multiple rig. Even the cables have been persuaded to curve like synchronized swimmers. The style is a tantalizing blend of the military and the surgical. I'm rarely of a religious turn of mind but I do believe I could worship that... How do you get the scopes parallel? Olly -
Show us your dual scope set ups
ollypenrice replied to spaceboy's topic in Discussions - Scopes / Whole setups
Quite surprizing, really. However, I've seen enough of very fast optics to know that they are not for me. I prefer two slower ones! I'm not asserting anything, here, other than a purely personal preference. Olly -
Show us your dual scope set ups
ollypenrice replied to spaceboy's topic in Discussions - Scopes / Whole setups
Ours is all about speed. The two Taks are aligned using a Cassady T Gad under one and carried on a Mesu 200 which could easily handle another two... Five hours become ten hours. Or maybe, in terms if residual noise, it's better than that because the noise which calibration fails to remove is partially neutralized when combined. Note that doubling the scopes is only the equivalent of coming down one F stop. However - and here's the key bit - these F5 refractors work. Always. Every single time. They have a workable depth of field. If you go, instead, for a single faster astrograph you have to be ready for what that entails in terms of making it work. Good luck! Olly -
Sky Watcher 18" StarGate first review
ollypenrice replied to raanany's topic in Member Equipment Reviews
It seems as if it's well worth the extra bit. Olly -
TS Optics Imaging Star 80 mm f/4.4 Flatfield APO review
ollypenrice replied to ultranova's topic in Member Equipment Reviews
Totally mad! 'Mad as the sea and wind when both contend which shall be mightier.' -
TS Optics Imaging Star 80 mm f/4.4 Flatfield APO review
ollypenrice replied to ultranova's topic in Member Equipment Reviews
F7? That's not.... Olly -
TS Optics Imaging Star 80 mm f/4.4 Flatfield APO review
ollypenrice replied to ultranova's topic in Member Equipment Reviews
I think that in this case and in many others there is an interaction between the buyer and the seller in which the seller anticipates what the buyer wants (in this case small fast refractors at less than half Tak price) and tries to deliver it. Inevitably competition between manufacturers means that they don't want to be the ones to say they can't do it, they all want to be the ones who say they can do it. So they push to the very limits of what they can do, they get some prototypes to work, and they go into production. This interaction is 'policed' by the laws of consumer protection. If they say the scope can do it, it must do it or the sale can be recinded under the law. This system is working, but it strikes me that it is creaking as a system since customers like you are being put through endless faffing about which, in the end, will not be recompensed. Nobody will pay you for your time. My contention is that it would be better all round for the consumer to demand a little less and the manufacturer to promise a little less by either charging a little more or easing off on the spec or both. If this were a defence procurement contract and you were dealing with the manufacturer to decide price and spec I strongly suspect that you'd pitch in for a slightly slower F ratio and - quite possibly - a slightly higher price. The free market is not a procurement contract, it's an environment in which manufacturers are tempted to promise the impossible. I've said this before but I think the purchasing community should start to make it a bit clearer to manufacturers that we only want products which work. I can guess that they might come back with, 'Yes, but you won't buy them if we make them, you'll buy the ones our rivals fail to make reliably...' Olly -
Sky Watcher 18" StarGate first review
ollypenrice replied to raanany's topic in Member Equipment Reviews
I always feel it's sad to think that the cheap Chinese import might put a guy like David Lukehurst into difficulty but it seems it's very much the other way round. Great review, very honest. For all its faults, and even though I'd go for a Lukehurst myself, I expect you'll get some great nights out with this when you've sorted it out. The dust lanes in M31 are, as Peter said, off centre and are very distinctive from a dark site and with the galaxy near the zenith. The elevation makes a big difference. Olly -
TS Optics Imaging Star 80 mm f/4.4 Flatfield APO review
ollypenrice replied to ultranova's topic in Member Equipment Reviews
Shoot me down in flames by all means but I see no reason to believe that the manufacturers know how to mass produce these small fast refractors with an acceptable probability of their working to spec. We have moved from the consistent successes of the stalwart ED80 (F7.5/F6) to thread after thread of dodgy corners and distorted stars. Is it not time to ease up on the flashy numbers and settle for something more like F6? I'm not a fan of extreme optics because I like optics to work. Lord knows, the IT side of the imaging business gives plenty of opportunity for random failure. At least optics can in principle be perfectly reliable, night after night, if you don't ask for more than the makers are competent to deliver. I could live with F6 and I believe the mid-price manufacturers know how to do that. It's a bit like houses. The developers want to be able to put '4 bedrooms and garage' on the description so you end up with garages in which you can't open your car door and bedrooms in which you can't fit a bed. I counsel F6! Olly -
This is a beautiful job. Are you a professional in the machine shop? Welding stainless isn't for everyone. It does give the whole thing some real class. (I am probably the worst amateur welder in Europe. ) We have a 20 inch F4. It's such a nice size, big but not ridiculous and not too terrifying at the zenith. Olly
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This seems like a good idea. It arises from an honest look at the reality of the present situation. The manufacturers are underpricing and failing to achieve the QC their designs deserve. We can argue about whether that's their fault or our fault or we can give FLO's idea a chance. If I were in the market for one of the scopes in question I would, without any hesitation, give this deal a try. Olly
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TS Optics Imaging Star 80 mm f/4.4 Flatfield APO review
ollypenrice replied to ultranova's topic in Member Equipment Reviews
That is a good and thorough review. I'd call F4.4 more than 'reasonably fast' for a refractor, I'd call it screamingly fast! Not many refractors go inside F5, after all, and doing so is never going to be easy for a maufacturer either optically or mechanically. I hope the fine tuning of tilt and chip distance go well and that you'll be back with more. Olly -
I'm slightly wary of asking this - but what's 'insertion rubber?' How about having one plywood sheet with layers of rubber on both sides and one with a handle as per Shan's suggestion. Place the double sided one on a worktop, lay the offending rings on it and press the other one down turning with the handle. Come on FLO, this is right up your street! Olly