I was wondering how much a lens or scope to spot the tail livery of planes at 31,000 feet would cost me?I'm inLondon, England and I get a lot of trailing flights flying past my house and so I want to able to see what airline these are.Is there any chance that I would be able to see the regs of planes this high?Thanks,Alex

Alex,
It is very difficult to make out a reg at that height although not impossible. The important thing other than a big lens (1200mm or more) is light. If the sun is almost setting and the jet is almost overhead, you can almost see the "under wing" reg #...It is not possible (I do not think) to make out a reg on the side of a fuselage because that would mean the jet is much farther away since one cannot see an overhead flight's side fuselage's reg
mark g

You want a good telescope or pair of binoculars.

Over the last 46 years I've used both and am very much a telescope man. Very high power binoculars are expensive and the most frequently seen high power binos are 20x50 or 20x70. This means the magnification is 20 and the object (large) lens is 70mm.

These figures are important, as will become clear.

There are many telescopes around which offer zoom magnification up to 60 or even 70 times BUT such magnification is rarely important.

Ocular equipment such as this will only give good performance if enough light hits the eye through the magnifying lenses. So, a telescope which is 30x30 will work in excellent light, but the image will be relatively dim.

Magnifications above 40 are of dubious value as you lose definition due to the magnification of the inbuilt shaking of your body and the magnification of any heat haze. You also need an ever bigger object lense for every increase in magnification as the amount of light entering the eye through the lenses determines the brightness, sharpness and "readability" ofthe image..

Probably the best bet you can go for is a 30x60 or 30x70 telescope. This will give excellent magnification, a good light input, a sharp image and will not break the bank. You are young enough not to have too much body shake, you will learn very quickly how to use walls and other objects as steadying devices, so you won't have the expense of a tripod and, after a short time, you should be able to use the telescope "freehand".

As for what you will see, you will certainly see tailschemes and be able to read billboard and even smaller titles. Registrations - no, not at FL310, but much lower, yes. I'm afraid the days of massive underwing registrations on East European airliners, when I could "pole off" Interflug, CSA, LOT, TAROM, Aeroflot etc. at 310 and above have all but gone.

Try looking at Air Pictorial and other enthusiast magazines for UK suppliers or look at Sherwoods and Jessops sites on the web.

Finally, what do I use?

In 1985 I bought a Tamron 20-60x75 mirror lens zoom telescope. This has travelled the world with me and is looking fairly battered. The mirror lens enhances the performance and it is good at up to 50 magnification (heat haze permitting) but I normally use 30 magnification as this gives the best, overall performance. In 1985 it cost me £400 but I haven't seen too many mirror lens terrestrial 'scopes available in recent years.

If you can find and afford one, it would be a very worthwhile investment.

Cheers guys,
Phil do you have the address for Sherwoods and Jessops sites?Thanks,Alex

Go into Yahoo UK and type either name and you'll get straight there

Donder10,
Jessops Online

Martin

Phil you suggested a 30x60 or 30x70--how much would you think one of these would cost?Thanks alot ,Alex

Sorry Alex,

I'm way out of date with prices. The web pages should tell you but, in honesty, if you want a piece of equipment that will give you good optics, will last and take the odd knock or two without being damaged , don't expect to pay under about £150.

Another source of information would be bird spotting pages/magazines. Anything the "twitchers" find useful would be useful for aircraft,

Hi PhilB, I e-mailed Jessops,and this is the reponse I got..

Hi Alex

Thank you for your recent enquiry concerning the Telescope for
watching planes.

I really don't think there would be a telescope suitable for watching
planes at 31,000 feet.

It would probably be better if you used a pair of Binoculars for the
logging of registration details at the airport Jessops range start at
as little as £16.90, but I would recommend the 10 x 50 coded as
JESB1050ZCF at £34.90.

My colleagues at your local Jessops store will be only too happy to
help you further should you choose to purchase this item.

If I can be of further assistance to you please do not hesitate to
contact me.
>>>>Do you think it was worth spending £35 on some binoculars just for use at the airport and then say £200 when I save up to get a telescope for spotting planes at 31,000 feet+...Thanks alot,Alex

So much for training and expertise in today's stores!

A 10x50 will give you a good image as the object lens is big enough to let in plenty of light for the magnification BUT....

To see how a 10x binocular would work, write the letter L on a piece of paper with the vertical leg 1/2 inch long and the horizontal 1/4 inch. Take anothor piece of paper and draw the vertical 5 inches long and the horizontal 2 and 1/2 inches. That is the effect of 10x magnification.

Now take a third piece of paper and draw 30x magnification, i.e. the vertical is 15 inches and the horizontal 7 and 1/2 inches... sorry, forgot, you need a big piece of paper!!!

They probably have a target to sell binoculars at present so don't waste your money because, at that price, the optics will be poor.

Go into Smiths or another newsagents and browse the birdwatching mags. If you can't afford one of the scopes in them, look at some of the binoculars, which will be cheaper, and see if you can afford some 15x, but my guess is that, for good optics, they will be getting to the price of a scope.

There is no way round the fact that good optical equipment costs. If you need something quickly, try buying second hand from a non chain camera store - most have an odd piece of eqyuipment for sale, but the best advice is to save up.

Cheers Phil, you have been a good help