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0 Responses
18-250*
:/ kinda got me excited there for a moment.
Slightly off topic..but thats not not for me
No one seems to have a hint of what f number the rumored new Sigms 300-600mm lens will be so I searched old patents for a clue…
I dug up something interesting…
Back in 2013 Canon patented several long lenses with built in teleconverters….I have heard absolutely no rumers that they are actially going to build them but guess what I found,,,,
A patent for a 300-600mm f 5.6 with a built in 1.4x teleadaptor by Canon in 2013.
My best guess therefore is that Sigma will make thier new 300-600 f5.6 in order to outperform Tamron and compete with Canon if they ever decide to build this.
F .095
600mm F.095 would be a little impractical as it would weigh in excess of 20,000 lbs
+1
At Photokina 12 I visited the Sigma stand where they installed a demonstrator of the 200-500/2.8.
It felt more like operating a flak cannon on a battleship than testing a lens. 🙂
Just a bit larger than a normal 600mm
If that is the 600mm f .095 than the tiny baseplate attached to the mounting collar is a 26 wheel tractor trailer.
It’s helium filled for better balance.
Helium would have a different lower index of refraction than air and therefore change the optical properties of the glass elements they come in contact with to perform as if they had a higher index of refraction.
This would actually allow the glass elements to be thinner and lighter.
The use of helium or better yet hydrogen if permenently sealed between glass elements could actually be beneficial in lens desighn. Just as exotic glasses are currently used to improve lens performance..exotic gasses could also be used.
The gases themselves would impart no weight saving as the sealant alone would weigh more than the savings.
And your f .095 lens would of course still not be doable
I actually found some lenses similar to your proposed lens
It consists of a huge parabolic mirror in about 100 sections each individually aimed.
It would not work too well with todays cameras as there would be a slight heat build up problem.
This one ..see wikopedia ….is in france on a mountain top.
It generates temperatures in excess of 3500°c and is called a SOLAR FURNACE.
That’s not necessarily true, there are multi segmented telescopes currently in use. Since they are not aimed at the daytime sun there is no danger of damaging the image sensor. http://en.wikipedia.org/wiki/Ritchey-Chr%C3%A9tien_telescope
The Canon 200-400 is around 11.5k€, the Nikon 200-400 is around 6.2k€.
The existing Sigma 300-800 is around 7.1k€.
Why should they make 300-600/5.6 (which would be with 1.4TC 420-840/8) , which would likely cost same or more than the existing 300-800/5.6?
If I’d be responsible at Sigma I would demand a reliable business case before even considering spending a dime into a technical concept.
I am not predicting a biilt in teleconverter on a Sigma lens even though they have a 50-500 with built in converter.
What I am suggesting is that Sigma might soon put out a 300-600 f 5.6
Based on comparison to existing lenses the specs MIGHT look like this
300-600mm f4.8-5.6
Filter thread 125mm
Weight 8lb
Length 11.5″
Cost$1998.00
This is just an educated guess on my part based on what the current Tamron 150-600 that this lens would be specifically intended to compete against.
It would also compete against the lens Canon patented if they ever built it.
The popularity of the new Tamron lens would be the primary factor in the decision to make a lens like this
I do not expect these specs to be exact…but I think something like this is very possible.
You’re pretty up on things, Barry, so you’ve probably seen this Tony Northrup video reviewing the Tamron 150-600. Heck, I’d even seen it before and forgotten about it!
http://www.youtube.com/watch?v=1fmMG5jgDwk&list=PLwIVS3_dKVpsjSZrQ7H-Nw8GQ7ZuDYyaD
Anyhow, it confirms the softness of the lens which is going to be the sort of good-enough sharpness I experience with my Tamron 200-500mm but still grimace over.
For maybe the last few weeks I’ve been watching Minolta 400mm f/4.5s on FleaBay which you can pick up for roughly $2,500+ in a complete or near complete (maybe missing the trunk case) kit in excellent condition. I’m not going to move on anything (less an usual deal pops up – figure the odds) because I’m waiting to see what unfolds with the Tammy 150-600, see if Sigma (50-50 chance?) announces a response, and waiting to see if Sony surprises me with a 400mm f/4 I can afford (about a 10% chance). Point being the video compares the Tammy to a Canon 400mm f/5.6 prime which slaughters it with a 1.4x teleconverter.
Thoughts?
Currently the Tammy 150-600 seems to be by far the best VALUE in a supertele bird lens…for best results use f8 for crop sensor and f11 for ff sensor as this will produce best sharpness.
Most reviewers agree sharpest up to 500mm and a little soft at 600, but based on mtf charts it seems that stopping down as indicated will compensate for that.
Although this lens seems to currently be a must have I expect Sigma to quickly get a competing lens in production.
Rumors are 300-600 of unkown speed.Based on the current market my instinct says f 5.6 and they will try to keep it just under $2000.
I expect better quality especially at 600mm end and about 8 lb with 125mm filter thread.
I think specs like those would be necessary to compete with both Tamron and possible future Canon lenses.
If my lems does not arrive in Sony mount ln time for my next bird shoot I am cancelling my preorder…that way I can evaluate everything that is anounced in September and decide without any pressure which new lens AND camera brand I will get.
Since this lens will never leave the camera I put it on I will have lots of options and no pressure.
These specs are totally my own quess so dont actually count on them being correct.
I never heard of a 28-250mm Sigma lens. Could it be you are writing of the 18-250mm lens?
The 18-250 is old and less than mediocre. At my very beginning on DSLR I compared this lens to other superzooms – the result was the same for the Sony and the Tamron 18200.
In order to get halfway decent sharpness you needed to stop down to f8 at least. Poor colors, low to medium contrast, and heavy distortions on both the low 10mm and the upper 30mm.
If I’d still be APS-C user, I would not take this lens if they’d give it for free…
Any lens that goes from wide to tele ist going to lack quality.
A lens that goes from very wide to medium telephoto lke this is by nature always going to be a very poor quality lens.
Some people want a single do everything lens of modest cost and are willing to accept the poor quality in order to get that.
These are the people that will buy a lens like this.
It looks pretty compact so if you’re taking it on a family outing where you’re not going to be dragging 40 lbs of kit in a backpack it makes sense. You’re not going to be making art canvas prints with it but it’d be decent enough to post on Facebook, email grandma, or even the 5″ photo frame in the den. Better than using a smartphone.