...and another thing. Where's my 500 f/5.6 DO at £3-4k to compete with Nikon, Canon?
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We fill doughnuts with jam.Hmmm.. strange. First thought was a standard lens, but on seeing it was a mirror, disappointing. Useful for astro, focal lengths tend to be 1m or more. But IS? Long astro lenses will be mounted on heavy duty trackers which don't need it. And mmmm... donuts!
Not unless Topaz can come up with an AI donut filler?
1200mm and up puts you in amateur telescope ranges that are useful. Lens IS coupled with sensor IBIS allows in camera/lens tracking due to earth rotation. The stabilizing would allow for longer exposures where you could track and stack images to get higher resolution shots of stars and objects.Do astro photographers shoot with 400-800mm focal lengths? My impression is they either go wide to catch a big slice of the sky, or long to, say, have the moon fill the frame.
How much would IS help for astro, when the lens is mounted on a sturdy tripod anyway?
Do astro photographers shoot with 400-800mm focal lengths? My impression is they either go wide to catch a big slice of the sky, or long to, say, have the moon fill the frame.
How much would IS help for astro, when the lens is mounted on a sturdy tripod anyway?
I remember watching a youtube video with Jared Polin, where he took video of Saturn using the R5, 800mm f/11 and 2x converter. Was very shaky, because he had the wrong head on his tripod. But seeing the rings of Saturn in a video was amazing.Do astro photographers shoot with 400-800mm focal lengths? My impression is they either go wide to catch a big slice of the sky, or long to, say, have the moon fill the frame.
How much would IS help for astro, when the lens is mounted on a sturdy tripod anyway?
Because they are usually a good compromise for focal length (and thereby magnification), size/weigth and costs. There are several astrographs that are faster. For example Officina Stellare makes a 980/2.8 and a 720/2.2 - although they don't use a pure Schmidt-Cassegrain schema but a Riccardi-Honders one - it's a modification with added lenses just like the Canon design to obtain a larger corrected field.there have been mass-produced Schmidt cassegrain telescopes (SCTs) as fast as f/6.3, but generally they’re f/10
They have - it's were you attach different types of eyepieces to select the magnification. Although you can also attach a camera directly without any other optics.but don't have the extra corrective lenses (shown in the patent) after the 2nd mirror, shortly before focusing on the sensor
The patent has IS on the lensesThe only thing that stopping me from buying mirror lens is absence of IS
Thank god i haven't pulled the trigger on rf 800 f11 yet
Yeah, but I think that's really cool just like it is.Zero chance it would be manual focus.
As for filling in the holes yourself, good luck with that!
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I know nothing about astro. Most of the posts I see here about astro want fast lenses. Am I correct to assume that these mirror lenses need to have a tracker for astro? I'm guessing the guys real serious about astro already have one?This is very cool and long overdue. Not likely that these are MF, so Cats that are a full stop faster than those of old with IS and AF would be very interesting. I have quite a collection of old mirror lenses and some are very sharp (e.g. 500 mm Minolta MD and 1000mm Nikon). The challenges are always accurate focus and adequate stability, although the R5 IBIS helps a lot with the latter. There is another angle to the timing of this. The Chinese telescope industry is currently in shambles. Between lawsuits, lack of production, and whatever, you simply cannot buy a Meade or Celestron telescope these days. That 2000 f/15 would be quite small and would be useful in telescope land. Note that the biggest of these (the 1200 f/8) is still only 6 inches in diameter and still tiny compared to a big white.
I invented the dish rag for exactly that purposeI wonder what wild life fears more ,harmless mirror shine 100meter away or big guy with big white 30meter away?
They could make also something to hide mirror shines when camera isnt taking pictures
Unless you're ready to switch to Nikon, the Nikon is no competition. Otherwise, I predict 2027....and another thing. Where's my 500 f/5.6 DO at £3-4k to compete with Nikon, Canon?
I predict never. They are simply looking at offering different things and not going directly head-to-head against each other with every lens.Unless you're ready to switch to Nikon, the Nikon is no competition. Otherwise, I predict 2027.
I am a very happy RF 100-500mm user, as evidenced by the number of shots with it and the RF 1.4x and 2x I’ve posted. But that Nikon 500mm f/5.6 PF is the best lightweight lens I‘ve owned and I’d rather buy the Canon equivalent of it than a 400/4 even if they could reduce the weight right down. The range with TCs of 500-700-1000mm (like on the 100-500mm too) is more useful to me than 400-560-800mm. My 400mm DO II spent most of its time with a 1.4 or 2xTC on it.I predict never. They are simply looking at offering different things and not going directly head-to-head against each other with every lens.
Canon is going 400/4 versus 500/5.6, 100-400/5.6-7.1 and 100-500/4.5-7.1L versus a 100-400/4.5-5.6 and 200-600/5.6-6.3 (I guess the Nikon 200-600 will be close to Sony in this case) etc. etc.