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Brian Howell
登録日: 2006.05.22 記事: 39
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日時: Tue Mar 31, 2009 1:39 am 記事の件名: 1/2" or 1/3" Does it matter? |
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In my quest to find fast lenses I have run into a reoccurring problem, it seems that 1/2" CCD cameras are on their way out as most of the lenses that are available are for 1/3" format cameras.
I ordered the recommended 1/2" Watec 902H2 Ultimate but most of the lenses I see are for 1/3" cameras. Why are 1/3" cameras not recommended?
Also, does anyone know why Fujinon, Computar and others have discontinued making F0.8, F0.95 and F1.0 lenses??? I would think these fast lenses would be in high demand over F1.2 to 1.8 lenses that seem to be available currently. |
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SonotaCo Site Admin
登録日: 2004.08.07 記事: 12671 所在地: 139.67E 35.65N
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日時: Tue Mar 31, 2009 9:12 am 記事の件名: Re: 1/2" or 1/3" Does it matter? |
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Brian Howell wrote: | I ordered the recommended 1/2" Watec 902H2 Ultimate but most of the lenses I see are for 1/3" cameras. Why are 1/3" cameras not recommended? |
It is because image sensor size of the pixel in 1/2" CCD is larger than that of 1/3" CCD.
It means 1/2" CCD collects more lights, and the sensitivity, S/N or the dynamic range is higher.
Brian Howell wrote: | Also, does anyone know why Fujinon, Computar and others have discontinued making F0.8, F0.95 and F1.0 lenses??? |
It may because night sky watchers are not so many.
I believe Fujinon YV2.7x2.9LR4D-SA2 (f2.9-8mm, F0.95) is not discontinued yet. It is widely used for security purpose in Japan.
This lens is for 1/3" CCD, but it can be used for 1/2" CCD in the range of f=5..8mm.
Here is a comparison with CBC 6mmF0.8. See images.
http://sonotaco.jp/forum/viewtopic.php?t=1565 |
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Brian Howell
登録日: 2006.05.22 記事: 39
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日時: Tue Mar 31, 2009 10:24 am 記事の件名: |
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It looks like there is a noticeable difference in F0.95 and F0.8. Is it possible for a lens to be faster than F0.8? Maybe F0.5? A larger objective should also gather more light.
I wonder how expensive it would be to have some custom lenses manufactured at F0.8 or faster if possible with a large objective. |
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SonotaCo Site Admin
登録日: 2004.08.07 記事: 12671 所在地: 139.67E 35.65N
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日時: Tue Mar 31, 2009 1:32 pm 記事の件名: |
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Brian Howell wrote: | It looks like there is a noticeable difference in F0.95 and F0.8. |
Yes, there is. but it is the only way now.
Brian Howell wrote: | Is it possible for a lens to be faster than F0.8? Maybe F0.5? |
A design of F0.5 lens is existing, it may be the theoritical limit.
As far as I know, F0.7 was the fastest lens that have ever produced.
Today, there is announcement of F0.75.
http://www.raymax.co.jp/japanese/data/newpdct/night%20shot.html
I do not know how much it will be. May be more than a car?
Please let me know if anyone knows the price.
Brian Howell wrote: | I wonder how expensive it would be to have some custom lenses manufactured at F0.8 or faster
if possible with a large objective. |
May be re-production of CBC lens will be most lowcost.
Otherwise, it may be natural if the price is more than a cruiser . |
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Brian Howell
登録日: 2006.05.22 記事: 39
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日時: Wed Apr 01, 2009 2:55 am 記事の件名: |
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Quote: | A design of F0.5 lens is existing, it may be the theoritical limit.
As far as I know, F0.7 was the fastest lens that have ever produced.
Today, there is announcement of F0.75.
http://www.raymax.co.jp/japanese/data/newpdct/night%20shot.html
I do not know how much it will be. May be more than a car?
Please let me know if anyone knows the price. |
Thanks for the information. That is close to what I want. I might check with some of my lens contacts to see if they know about price and availability. |
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Brian Howell
登録日: 2006.05.22 記事: 39
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日時: Thu Apr 02, 2009 10:44 am 記事の件名: |
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I contacted some people but they could not find a price or even a US or Canada distributor for this lens. |
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Brian Howell
登録日: 2006.05.22 記事: 39
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日時: Fri Apr 03, 2009 9:54 am 記事の件名: |
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I've contacted another lens supplier. He may be able to get me some information next week on the F0.75 lens. I'll have to wait and see. |
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Lightningwizard
登録日: 2007.10.19 記事: 165
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日時: Sat Apr 04, 2009 8:04 am 記事の件名: |
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Wow, that is indeed an exciting anouncement... 6-36mm is very versatile for sprites and F0.75 allows to keep the gain (noise) low. Is it for 1/2" or 1/3" ?
I currently use a 12mm F0.8 but have just bought a manual 8-48mm F1.2 for $50. It should be nice for sprites but I probably need to increase the gain a bit.
By the way, I am coming to Japan (Chiba city) in May for the JPGU conference, it could be great to meet fellow UFOcapturers! (and shop for the new lens )
Oscar _________________ Weather & Photography
http://www.lightningwizard.com
EuroSprite blog:
http://eurosprite.blogspot.com |
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SonotaCo Site Admin
登録日: 2004.08.07 記事: 12671 所在地: 139.67E 35.65N
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SonotaCo Site Admin
登録日: 2004.08.07 記事: 12671 所在地: 139.67E 35.65N
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日時: Mon Apr 06, 2009 4:34 pm 記事の件名: About RTM6Z0607 |
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I have contacted about RTM6Z0607 to the maker
and the dealer who is assigned by maker.
I got following information, but everything is not so clear yet.
1) The meaning of suffix
M: manual remote control iris.
G: DC iris.
GA: video iris.
P: with preset potentiometer.
2) The price is not decided.
It will be responded by the dealer against the request for quotation.
The dealer's home page is
http://www.uniel-denshi.co.jp/INQUIRY/INQUIRY.html
3) About the controller.
RTM6Z0607 needs a controller, because it is zoom lens with motor.
The controller will be cost 30,000 Yen to 100,000 Yen.
(The Raymax's controller RA4000 is priced as 102,300Yen)
4) Availability
Raymax says that the production is ready, but it is build-to-order product.
So, it will require at least 3 weeks or more to the delivery.
5) Testing
Maker does not offer testing. Dealer has not stocks.
Therefore testing may be difficult.
6) About the maker
Raymax has been producing lenses as OEM source of
television lens of Angenieux(France). |
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thedavid2007
登録日: 2006.08.15 記事: 26
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日時: Sun Jul 04, 2010 6:55 pm 記事の件名: Re: 1/2" or 1/3" Does it matter? |
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Brian Howell wrote: | In my quest to find fast lenses I have run into a reoccurring problem, it seems that 1/2" CCD cameras are on their way out as most of the lenses that are available are for 1/3" format cameras.
I ordered the recommended 1/2" Watec 902H2 Ultimate but most of the lenses I see are for 1/3" cameras. Why are 1/3" cameras not recommended?
Also, does anyone know why Fujinon, Computar and others have discontinued making F0.8, F0.95 and F1.0 lenses??? I would think these fast lenses would be in high demand over F1.2 to 1.8 lenses that seem to be available currently. |
You can check some online auction sites for discontinued 1/2" lenses. |
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