IBM

Well some one went through a lot of trouble with all the pictures, pulling a hoxe , if it is , but now I recall seeing it some where and payed no attention as , I'm waiting for a good one to come out , but the only one I can see is the Nikon 200-500 VR . I'm losing $200 a week I to the slot machines, but holding of from spending it on something worth while , I must be nuts ,

IBM

And you Mt shooter , of all people should n
Know as your usually right on

tresap23 Loc: Texas

And POINT TAKEN lol! Cut me some slack, haha. I had spent 2 days with my 3 year old granddaughter, who never got tired of playing!! By the time I got to the camera shop, I was totally exhausted, with my nails (and fingers) painted 3 different colors, and "Frozen" glitter eye shadow on my eyes. In case you are not familiar, it is a new Disney princess movie, the color of the shadow was BLUE!!!! I can't imagine what my hair looked like, since it got "fixed" ALOT!!! So, by that point I discussed "maybe" an interest in a new lens. You know how that goes. Can't go in a camera shop without looking at new glass!! It is a horrible addiction!! So, I am sure I got the F1.8 on the Sigma confused with the Tamron 16-300 3.5. However, I will be checking into this further!! I "hate" being wrong. But, yes, I know it can't be true. so I must be wrong, right?? Anyway, thanks for the feedback on the lenses. And I will retract tomorrow I am sure!. I did take your advice and went back to look at pictures, but I had already cleaned my card!!I do that when I am organizing photos. I delete as much as I can. to free up space. I found "one" that the lady took of the floor It did say 1.8 but at 35mm. No lens manufacturer info was on the file. quote=MT Shooter]Because NO SUCH LENS EXISTS. I suggest you look at the Exif data from those shots and see what you were ACTUALLY using, it clearly was NOT what you were lead to believe.
Based on your size description I would venture to guess you tried a Sigma 50-100 mm F1.8 lens, the worlds ONLY other F1.8 zoom lens besides Sigmas 18-35mm F1.8.[/quote]

IBM

Mt you don't have to guess just open up the post with all the blue writing and you will see the lens and there is a bunch of sample pic you can look for your self , it's on the same, e page as this one , go in and look then come back a and give us your expert opinion, it's a pretty
Good farce , If YOU Ask ME, What Is THE Exif data

MT Shooter Loc: Montana

That "post" has nothing to do with the OPs description of the lens she used. She said it was "the size of a 70-200mm F2.8" but was an F1.8, hence by guess of the Sigma 50-100mm F1.8, the ONLY F1.8 zoom of that size.

mwsilvers Loc: Central New Jersey

You're mistaken. A 16-300mm f/1.8 lens does not exist. There are only two zooms in existence with an f/1.8 fixed maximum aperture. Both are Sigma, and both are designed for crop sensor cameras. One is the lens mentioned in the title of this thread, the 18-35mm f/1.8, the other is the new 50-100mm f/1.8. That lens is the same weight and close to the same size as your 70-200 f/2.8 II. That's it. There are no other f/1.8 zoom lenses in production by anyone. It appears you're confusing the specs of the 50-100mm. Quite a difference from a 16-300.

tresap23 Loc: Texas

I am sure I am Thanks for the feedback!

mwsilvers Loc: Central New Jersey

Actually, she very clearly stated it was a 16-300mm f/1.8 in two seperate posts. Please reread. However, she was clearly referring to the Sigma 50-100 f/1.8. With so much gear and so many numbers to remember it's easy for someone not familiar with the products to get confused.

IBM

I dident notice the 1.8 f I just seen the 16-300 mm and thought this is what she seen , and the rest is history

leftj Loc: Texas

Yes I believe you are right. Th OP got their brands and fstops mixed up. I have the Tamron 16-300mm lens which I shoot on my 80D. Also have the Sigma 17-50mm f/2.8 which I am very pleased with.

tcampo11

Anyone have any more insight as to the original question? Thanks!

mwsilvers Loc: Central New Jersey

As I indicated the 18-35mm like some of the other Sigma ART lenses is known to have intermittent AF issues, especially at f/1.8 This problem is more pronounced with small, low contrast subjects in lower light. The problem is less pronounced as you stop down to f/2.8 and f/4. In other words using this lens is an occasional hassle, but the results are so good it's worth the effort. The only problem I'm aware of with the 80D is several reports of back focusing in Liveview.

amfoto1 Loc: San Jose, Calif. USA

The only 16-300mm that Sigma makes is an f3.5-6.3 variable aperture.

An "f1.8" that reaches 300mm would be near impossible, huge, very heavy and very, very expensive.

The actual, physical size of the aperture of a any lens is dictated by the focal length of the lens. Simply divide the focal length by the max aperture.... such as 200 divided by 2.8 = 71.

This is an optical imperative... there's simply no getting around it.

For example, a 300mm f2.8 has to have a 107mm diameter aperture. That's four inches (for the metrically impaired)... and that's only the opening of the aperture itself. The lens barrel will have to be larger to accommodate various mechanisms around the aperture. Your 70-200mm has to be large enough to accommodate a 71mm diameter aperture. The old Canon 200mm f1.8 needed a 111mm aperture. A 500mm f4 I use has a 125mm aperture (just shy of five inches), when wide open... That lens is about 6.5" in diameter, nearly 18" long without it's 6 or 8" deep lens hood, has a 150mm diameter front element and weighs about 8.5 lb.

For a 300mm lens to be be that "fast", it would need to have a 167mm diameter (6.5 inch) diameter aperture. The barrel of the lens would need to be about 7.5 or 8 diameter at the aperture to accommodate the mechanism. The front element of the lens alone would need to be around 180mm or 200mm in diameter (nearly 8 inches... think the size of a dinner plate). I'd guess it would weigh somewhere between 25 and 35 lb., due to all that big glass inside a large lens barrel.

In fact, Sigma does make an extreme telephoto zoom... One of very few reaching 500mm that's f2.8. (Might be the only one... I dunno.)

http://tambnguyen.com/wp-content/uploads/2012/04/01b151c88da08ddc655c0210.L.jpg

Sigma 200-500mm f2.8 APO EX DG IF

It's over 9 inches diameter, 28" long (without lens hood), weighs 35 lb. and costs $27,000. A "300mm f1.8" would have to be similar in size, weight and cost.

You were probably being shown the Sigma 18-35mm f1.8 "ART".... which is the "first of it's kind to have f1.8" aperture.

Another possibility... Sigma also makes a 50-100mm f1.8 "ART"... it's also a "first", as well as similar in size and weight to a 70-200/2.8.

Both the Sigma 18-35/1.8 and 50-150/1.8 are "DC" or "crop only" lenses (fine on Canon 80D or 7D-series or any of the other APS-C models... not usable on 6D, 1D-series or 5D-series full frame or APS-H formats).

tresap23 Loc: Texas

Ok, now I am so sorry I hijacked your post and got stuff started, but hey, I learned ALOT about lenses that I did not know. But I can tell you, the Sigma lens that you are asking about does produce amazing pictures! I tried that lens, and the 50-100 1.8. Both lenses were very nice!

mwsilvers Loc: Central New Jersey

Lol. You didn't hijack the thread you were trying to help. And you're correct, both the Sigma 18-35mm f/1.8 and the 50-100 f/1.8 are exceptionally nice lenses and are built like tanks. They are not cheap. The pair will set you back around $2000 for crop sensor only lenses. And for that money the focal range is limited. But, those who can work with these limitations will be well rewarded. It is rare to speak of truly unique lenses, but these two Sigma offerings have absolutely no direct competition. They are big and heavy, but the pair of them are the equal of 6 or 7 quality fast prime lenses, and everything in between.