Quote:
Originally Posted by gregbradley
Yes Samyang has shockingly bad quality control. It literally is a dice throw but some models I think have less issues than others. The 14 and 24 are a crap shoot.
Greg.
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They're worth it if you get a good one though!
Quote:
Originally Posted by multiweb
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Thanks Marc
Quote:
Originally Posted by Ryderscope
Very nice work Colin.
FWIW, I’m very happy with the results that I’m getting with the Samyang 14mm lens so far.
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I found the images from the Samyang 14mm on a D7200 to be quite pleasing once dropped to F/5.6, wasn't too happy wide open, just a bit soft. Not sure what my copy was like though compared to others.
Quote:
Originally Posted by gregbradley
You might need a support ring. There are generic rings for lenses on the market. Try ebay. You could then mount the ring on a dovetail and support the end of the lens so it does not shift.
Greg.
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Good idea. I'll have to do some playing inside to figure out where the movement is coming from. I am thinking that I need some stability on the end of the lens but I'm not 100% sure yet.
Quote:
Originally Posted by glend
Right you are Greg. I have a very nice camera snd lense support bracket that i purchased ftom Teleskop-Express:
https://www.teleskop-express.de/shop...etail-bar.html
No movement with this baby, fully adjustable with a sliding tripod type mounting post, and it comes apart so you can use the Losmandy base on other equipment when not using the camera holder.
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I might need something like this depending on what the gap is on a larger ring compared to the smaller ones. I might need the adjustment.
Quote:
Originally Posted by RickS
Nice work, Colin!
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Thanks Rick
Quote:
Originally Posted by Placidus
So long as you don't go pixel peeping at star shapes, it is a very lovely image. Beautiful depth and colour, and nicely processed.
Would love to see a retake once you've sorted out the flexure problem.
We had a vaguely similar problem with the Apogee CG16M, ten position filter wheel, and off axis guider all hanging off the focuser on the PlaneWave. Many kilos altogether. It would flex as the scope tracked in RA. At 3.5m focal length the tilt wasn't an issue, but the whole thing would go out of focus. We fixed it with a long hinged strut to support the camera as it tracked in RA.
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You're right, as long as you only look at the High Res and not the Full Res you cannot even tell that there is some serious tilt issues going on.
With Milky Way season coming up I may just have to do large regions of sky that way. It is a way of getting most of what Mike does with his FSQ106 + FLI16803 (FOV and image scale) but without the expense; lens, camera and filters costing as much as a second hand FSQ106. Mikes setup is obviously better and there is no disputing that
At the moment I have 86mm rings holding both the QHY163M and a part of the lens but it's holding it very close to the filter wheel. I think I need a ~100mm ring to hold the lens hood end for extra stability.