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Bill C-B's A900 remarks @ LuLa

wayne_s

New member
Bill,
Wow, interesting about the TC not supporting AF, that I didn't know.
70-400 lens is SSM so why can't they forward the signals from the camera
through the TC to the lens?
 

BackToSlr

New member
Bill,
Wow, interesting about the TC not supporting AF, that I didn't know.
70-400 lens is SSM so why can't they forward the signals from the camera
through the TC to the lens?
It does AF till equivalent aperture is 5.6 e.g till aperture is f4 ti will AF with 1.4xTC. If you use a non Sony TC, it will attempt to AF.

N
 
T

Tomm

Guest
It does AF till equivalent aperture is 5.6 e.g till aperture is f4 ti will AF with 1.4xTC. If you use a non Sony TC, it will attempt to AF.

N
Minolta / Sony AF systems are speced to work down to f/6.7 (either just the set f-stop or when using a TC, the f-stop x the TC multiplier), except for the 500mm f/8 RF mirror lens (which can AF using the center AF sensor). In the old days, Minolta had a 100-400mm AF zoom lens with a maximum aperture of f/6.7 at the long end, so their cameras had to support AF with that lens.

Actually, if the TC being used isn't chipped to modify the lens f-number (some 3rd party TCs just pass the electrical signals from the lens to the camera without mutiplying the f-stop info), the camera will attempt to AF even if the maximum aperture x TC multiplier is f/8 or higher. With that type of TC, the camera aperture display will show the un-modified f-number and un-modified FL in EXIF. (An f/5.6 lens with unchipped TC will still show f/5.6 not the correct f/8). When using the camera's meter, this isn't a problem. But if using a separate exposure meter and manual exposure, you would have to remember that the actual f-number is 1.4x that shown.

I have the 100-300 f/4.5-5.6 APO D lens. With a 3rd party 1.4 TC it will try to focus even at 300mm (modified f-number = f/8). With my MAXXUM 7 film camera it does lock focus in bright light. With my 700si, it just hunts. I haven't tried the combination yet with my A700.

I also have the Minolta 70-210 f/3.5-4.5. When combined with that TC it AFs fine at the long end on either camera (and my KM 7D and Sony A700) using any focusing sensor.

Tom
 
A big thanks from me too! Both Bill and Shelby were instrumental in my switch to Sony. Unfortunately, I may have to change to Canon for the video capability. So not pleased about that.
 

Bill Caulfeild-Browne

Well-known member
Thank you Dave & Bill.

I'm off to Hawaii for a month in mid-January and as I like to travel light it'll be the a900, Zeiss 24-70, Zeiss 135 and Sony 70-400 in my backpack.

As a back up body I'll have the a700 - with a Sigma 12-24 - in my suitcase along with a Leitz table top tripod. It works well on a wall, a car roof or braced against a tree trunk.

I'd love to take my MFDB but that's too much weight, needs a tripod, and would need a wife who wouldn't get annoyed at too much contemplative shooting!

Bill
 

douglasf13

New member
Bill Green, you could always just add a cheap Panasonic m 4/3 kit for video. According to Thom Hogan, in regards to video, 5Dii<D3s<GH1
 

Bill Caulfeild-Browne

Well-known member
Then how about a serious trip - Phase DF, P65+, 28 mm, 35 mm, 55 mm, 75-150 mm, 80 mm, 120 mm, 150 mm, 210 mm and 300 mm?

Now THAT's a lens appetite!

But in all honesty, would you take just an a900 and 50 mm for a month in Hawaii?

Bill
 
Thank you Dave & Bill.

I'm off to Hawaii for a month in mid-January and as I like to travel light it'll be the a900, Zeiss 24-70, Zeiss 135 and Sony 70-400 in my backpack.
Your definition of traveling light and mine are different (big zooms are heavy). More power to you though. I was shooting Canon the last time I was in Hawaii, but I think every 35 mm frame was either the 24-70 or 400.

along with a Leitz table top tripod. It works well on a wall, a car roof or braced against a tree trunk.
... or anchored in the sand.

I'd love to take my MFDB but that's too much weight, needs a tripod, and would need a wife who wouldn't get annoyed at too much contemplative shooting!
I shot a bunch of 6x9 in Kauai. Wife got mad every time I set up a tripod. She was even more mad that all her pictures were blurry.
 

douglasf13

New member
Bill C-B, I took a 50, 20, 85, 135 and 24-70 (the zoom primarily for the heli) when I was in Hawaii for 2 weeks, so I surely didn't travel light, either. :) Granted, I would probably consider just taking a 50 these days. Have a great trip. Hawaii is wonderful.

Bill Green, you may consider contacting Thom Hogan directly to ask specifics. Don't take my word for it!
 

dhsimmonds

New member
I have just returned from over a month in the Carribean including the "other" end of the island to Haiti....Dominican Republic. My trip included many of the old British, Dutch, Spanish and French islands including Martinique which is a department of France and as such a member of the European Community using the Euro as currency!! How did they get that through the EU parliament?? My trip also included mainland Columbia.

I went really light with the A900 and vertical grip, 24-70,70-400 and 100 macro plus my little Leica D-Lux-4 for "snapshots". In fact I could have dispensed with the 100macro, but I used everything else. Next time I would take the 16-35 instead of the macro.

A 28-110 would have been more useful than the limited 24-70 at the tele end and I must start looking for a Minolta F4 AF in this zoom range, as light is not an issue in that part of the world. In reality the A900 file size does allow for some serious cropping if really needed, so the 24-70 coped with most subjects.

I see that the rumour mill is suggesting that Sony will introduce many new lenses this year. Wouldn't it be nice if Sony were to produce a "roadmap" of their planned lens introductions similar to the one that Olympus produced for their 4/3 system. I am sure that Sony DSLR sales would soar if they were to do just that one simple thing.
 

douglasf13

New member
Dave, I don't think Sony has much a road map, and that's the problem. 2.5 years ago, they showed prototype lenses, and then released around half of them over the past two years. Then, they showed an all new protoype line up, and released all but one. I think they're trying to feel it out a bit. I sure hope they've listened about more primes.
 
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