Re: EOS Telescope Adapter Eyepiece IS Activation
I have nothing specific to say about EOS stuff here but, in general terms, about using a telephoto as a telescope: I wouldn't waste too much effort on it. I did. A few dollars too. I was able to neatly and professionally cobble together an adapter that enabled me to use my 800mm f5.6 IF-ED Nikkor with a very high quality Clave 2 o.d. 55mm eyepiece. I used it precisely once! The views were totally underwhelming when compared to even the most modest astronomical telescope or spotting scope, or even binoculars. Yes, this can be done. It is not WORTH doing though. That's my opinion, as a photographer, as someone who has actually done it, and, as an amateur astronomer for 40 years. -- Terence A. Danks Nature Wildlife Photography http://www3.ns.sympatico.ca/danksta/home.htm * *** *** * For list instructions, including unsubscribe, see: *http://www.a1.nl/phomepag/markerink/eos_list.htm ***
Re: EOS Telescope Adapter Eyepiece IS Activation
On 7 Dec 01 at 19:01, Malcolm Stewart wrote: I have the Minolta Monocular converter, and I've tried using it with my 500 f8 RF, 300 f4.5 MD and a few others. Not a really worthwhile experience. Before you spend money, I suggest you try it out using adhesive tape or whatever to hold it roughly in place. The converter has a focal length of 10mm and so you get an effective magnification of lens focal length in mm / 10mm. i.e. 10-40x on your zoom.What really kills it is the small exit pupil, making viewing seriously deficient. Your zoom would offer something like 0.7 to 0.8mm (approx. filter diam./ 40) at the long end, and I think you'll find it quite difficult to view in comfort. Give it a try before committing yourself. Hmmm;)) First, entrance/filter diameter on a 100-400/4.5-5.6 lens at 400mm is 400/5.6 = 71mm. Second, with magnification 40x (400mm lens divided by 10mm ocular), the exit pupil then becomes 71/40=1.8mmat the wide end, 100mm, this would become 100/4.5 = 22mm entrance diameter, and an exit pupil of 22/10=2.2mm. Third: we are talking about a functioning IS, which means that normal rules of minimum exit pupil in relation to hand-held 'eye-ergonomy' do not apply (6mm minimum, as in a 42x7 binocular)otherwise Fujinon wouldn't have made a mechanical image stabilized 40x16 with a price tag of US$5k and morenor would Zeiss have made a 60x20 IS unit with a similar price tag.once that exit pupil is rock steady, you don't need that large diameter as much, at least not in daylight (in daylight, 3mm is enough for a contracted eye pupil, at night, enlarged, it becomes 6mm). -- Bye, Willem-Jan Markerink The desire to understand is sometimes far less intelligent than the inability to understand [EMAIL PROTECTED] [note: 'a-one' 'en-el'!] * *** *** * For list instructions, including unsubscribe, see: *http://www.a1.nl/phomepag/markerink/eos_list.htm ***
Re: EOS Telescope Adapter Eyepiece IS Activation
On 7 Dec 01 at 13:29, [EMAIL PROTECTED] wrote: Try to find an EOS to T-mount (or M42) adapter. Sadly, these reverse adapters are rare as hen's teeth. T2-reverse *does* exist, but sadly^2 not for EOS or other modern AF mounts (MAF), only for older manual mountsthe latter are made (only) by Danubia AFAIK. Also: at one point in time, they were also listed for EOS/MAF, but despite all my research, I have never been able to confirm their existenceDanubia flatly denies any production for EOS/MAF8-)) That, plus the fact that you need full power+data to the lens, is the reason why I still think the concept of Novoflex reversal-ring plus auxiliaryout-of-the-way camera is the easiestthe eyepiece itself will have to be custom made in any case anyway. Heck, it would even allow stopping down to increase DOF:)) Mead makes a camera adapter (for their range of 1 1/4 telescopes) which can be used in reverse as an eyepiece holder for T-mount lenses. (Normally this adapter would be used to mount a T-mount camera to their telescope.) Motorized/computer-compensated telescopes are getting cheap enough to add one to the gear park, just for playing in the dark;)) But, they still don't have IS, so it's and/and, not or/or:)) -- Bye, Willem-Jan Markerink The desire to understand is sometimes far less intelligent than the inability to understand [EMAIL PROTECTED] [note: 'a-one' 'en-el'!] * *** *** * For list instructions, including unsubscribe, see: *http://www.a1.nl/phomepag/markerink/eos_list.htm ***
EOS Telescope Adapter Eyepiece IS Activation
Hi EOSophiles, I am trying to get hold of an eyepiece to put on my telephoto lenses, in place of the camera body so that I can use them as telescopes, in order to save weight (not to mention money) when out photographing watching wildlife. My first question is - does anyone know where I can come by such a device in a Canon EF fit? WJM has told me that he has seen such items advertised in the past but not recently. I have obtained a Minolta Lens/Monocular Converter found a company called SRB Film in Luton, England who are very helpfully prepared to convert the mount on it to Canon EF but I would also like to be able to take advantage of the image stabiliser on my 100-400. I found the lens contact pin-out details (below) on WJMs site but I am not an electronics expert. Can anyone tell me what is likely to be needed to turn on the IS? Martin Wiseman wrote the following on 10/8/98: - Looking at the front of the camera body and reading from left to right, the signals are: 1. VBAT 2. P-GND 3. P-GND 4. VDD 5. DCL 6. DLC 7. LCLK 8. D_GND Pins 2 and 3 are combined into one large contact on the lens. My interpretation of these signal names is as follows: VBAT- Battery power for driving motors etc. P_GND - Power ground - the return path from motors to battery negative. VDD - Power for the logic circuitry D_GND - Digital ground for the logic circuits DCL - Data from Camera to Lens DLC - Data from Lens to Camera LCLK- Data clock Other people have suggested that the data protocol is probably 8 bit serial at 62.5 kHz and possibly based on the Motorola SPI interface. --- I have not tried simply putting 6 volts across pins 1 2 yet but I imagine that there will be something more complicated than that needed to activate the IS. I have mailed MW who says that this may work however, especially if I add the correct data voltage across pins 4 8: Since early bodies were not aware of IS there can be no signal specifically sent to activate the IS but there may be a general wake-up call sent to the lens. Does anyone know what data voltage is used, to save me much effort with my multimeter trying to fool my EOS 3 into believing the lens is on when it isnt? WJM has suggested using the Novoflex Lens Reversal Adapter (that maintains electrical contacts to the lens when it is detached from the camera body) using the camera body itself to activate the IS. This would certainly do the trick, however it would be a bit cumbersome for bird watching to have the camera body suspended nearby all the time, the eyepiece would have to be used with the Novoflex adapter even on non-IS lenses because it would have to be suitably shortened. I would far prefer to find out what signals need to be sent to the lens to switch the IS on, try to incorporate a battery a device to give these signals into the eyepiece, or mounted on it. Anyway, this is all I have managed to find out so far I would greatly appreciate it if someone can enlighten me further before I risk blowing up my treasured IS lenses! Can anybody help please? _ Get your FREE download of MSN Explorer at http://explorer.msn.com/intl.asp * *** *** * For list instructions, including unsubscribe, see: *http://www.a1.nl/phomepag/markerink/eos_list.htm ***
Re: EOS Telescope Adapter Eyepiece IS Activation
I have the Minolta Monocular converter, and I've tried using it with my 500 f8 RF, 300 f4.5 MD and a few others. Not a really worthwhile experience. Before you spend money, I suggest you try it out using adhesive tape or whatever to hold it roughly in place. The converter has a focal length of 10mm and so you get an effective magnification of lens focal length in mm / 10mm. i.e. 10-40x on your zoom.What really kills it is the small exit pupil, making viewing seriously deficient. Your zoom would offer something like 0.7 to 0.8mm (approx. filter diam./ 40) at the long end, and I think you'll find it quite difficult to view in comfort. Give it a try before committing yourself. M Stewart Milton Keynes, UK - Original Message - From: Dave Knott [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: Friday, December 07, 2001 5:41 PM Subject: EOS Telescope Adapter Eyepiece IS Activation Hi EOSophiles, I am trying to get hold of an eyepiece to put on my telephoto lenses, in place of the camera body so that I can use them as telescopes, in order to save weight (not to mention money) when out photographing watching wildlife. My first question is - does anyone know where I can come by such a device in a Canon EF fit? WJM has told me that he has seen such items advertised in the past but not recently. I have obtained a Minolta Lens/Monocular Converter found a company called SRB Film in Luton, England who are very helpfully prepared to convert the mount on it to Canon EF but I would also like to be able to take advantage of the image stabiliser on my 100-400. I found the lens contact pin-out details (below) on WJM's site but I am not an electronics expert. Can anyone tell me what is likely to be needed to turn on the IS? snip * *** *** * For list instructions, including unsubscribe, see: *http://www.a1.nl/phomepag/markerink/eos_list.htm ***
Re: EOS Telescope Adapter Eyepiece IS Activation
Try to find an EOS to T-mount (or M42) adapter. Mead makes a camera adapter (for their range of 1 1/4 telescopes) which can be used in reverse as an eyepiece holder for T-mount lenses. (Normally this adapter would be used to mount a T-mount camera to their telescope.) Lars Hi EOSophiles, I am trying to get hold of an eyepiece to put on my telephoto lenses, in place of the camera body so that I can use them as telescopes, in order to save weight (not to mention money) when out photographing watching wildlife. My first question is - does anyone know where I can come by such a device in a Canon EF fit? WJM has told me that he has seen such items advertised in the past but not recently. -- Lars Michael[EMAIL PROTECTED] 87GT http://www.larsmichael.com/ * *** *** * For list instructions, including unsubscribe, see: *http://www.a1.nl/phomepag/markerink/eos_list.htm ***
